Dissertations / Theses: 'Plant cytotoxicity'

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Lindholm, Petra. "Cytotoxic Compounds of Plant Origin – Biological and Chemical Diversity." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5728.

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Lamola, Makgabo Stella. "Antimicrobial activity and cytotoxicity of extracts and an isolated compound from the edible plant Grewia flava against four enteric pathogens." Diss., University of Pretoria, 2015. http://hdl.handle.net/2263/52021.

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Bacterial infections of the gastrointestinal tract (GIT) causes vomiting, diarrhoea and even systemic infection. There is resistance to the commonly used antibiotics used to combat bacterial infection; there is a need for development of natural products into alternative and safer medicines. Studies have been conducted on the other species of the genus Grewia and there are reports of pharmacologically active compounds. There are no published studies up to date on Grewia flava. This study evaluated the antimicrobial activity of extracts prepared from berries, leaves, bark and roots of the edible plant Grewia flava against four enteric pathogens, Escherichia coli, Bacillus cereus, Staphylococcus aureus and Salmonella Typhimurium. The genus Grewia was named after Nehemiah Grew, an English plant anatomist and physiologist. It is a member of the family Malvaceae, formerly Tiliaceae. Plant material was extracted with acetone and water. The extracts were tested against the enteric pathogens using the minimal inhibitory concentration (MIC) method with gentamicin as positive control and ƥ-iodonitrotetrazolium violet (INT) as growth indicator. Antioxidant activity of the extracts was analysed qualitatively by developing the chromatogram in three different mobile systems and spraying the plates with 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and vanillin in sulphuric acid. Quantitative determination of antioxidant activity was carried out spectrophotometrically with DPPH, a stable free radical, and Trolox as a positive control. The antimicrobial activity was further determined qualitatively by the bioautography method. The toxicity of the extracts was determined using the MTT reduction assay against Vero monkey kidney cells, with doxorubicin as a positive control. The crude extracts of the leaves, bark and roots of Grewia flava were able to inhibit the growth of the enteric pathogens with MIC values ranging from 0.03 mg/ml to >2.5 mg/ml. Different compounds were visible on the plates after spraying with vanillin-H2SO4 reagent, and some of the compounds showed antioxidant activity when the plates were sprayed with DPPH and comparing the Rf values. Bioautography proved that the extracts were able to inhibit growth of the bacteria, S. Typhimurium and B. cereus. The acetone extracts were fractionated using solvent-solvent fractionation and five fractions were obtained; hexane, chloroform, butanol, 35% water in methanol and water. The chloroform fraction was effective against B. cereus, E. coli and S. Typhimurium with MIC values ranging from 0.15 mg/ml – 0.3 mg/ml. This fraction was also not toxic with a LC50 of 509.23 ± 24.88 μg/ml. Bioassay-guided isolation was carried out with the chloroform fraction, using open column chromatography, with silica gel as the stationary phase. The compounds were eluted with hexane: ethyl acetate solvent system at different polarities. Nine fractions were collected from the first column, and these fractions were tested for antimicrobial activity. Fraction 2 was the least effective with MIC above 1 mg/ml compared to fraction 3 which was effective against B. cereus and E. coli. On the bioautographs there was a visible clear zone with corresponding Rf on the thin layer chromatogram (TLC). Compound 1 was isolated from fraction 2 of the first column and compound 2 from fraction 3 of the first column, and the compounds were tested for antimicrobial activity and cytotoxicity. Probably due to synergistic effects, the single or isolated compound was less effective than the mixture of compounds (i.e. the chloroform fraction and acetone crude extract). The compounds were less effective against the tested microorganisms than the fraction and extract. Compound 1 was the least toxic with LC50 of 39.38±3.21 μg/ml compared to LC50 3.02 ± 0.03 μg/ml of the positive control compound, doxorubicin. Compound 1 was identified as Lupeol. The indigenous edible plant, Grewia flava contains antimicrobial compounds, as indicated by the inherent free radical scavenging activity and could therefore be used as a natural product with little toxicity to host cells. Further in vivo studies have to be conducted to confirm the toxicity.
Dissertation (MSc)--University of Pretoria, 2015.
National Research Foundation (NRF)
Paraclinical Sciences
MSc
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Bendová, Agáta. "Příprava bioaktivních krytů ran a testování jejich interakce s lidskými buňkami." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-401867.

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The thesis was focused on the preparation and optimization of the preparation of wound dressing from materials with bioactive ingredients. In this work were prepared nanofiber dressings based on polyhydroxybutyrate and non-fibrous dressings from alginate and chitosan. Nanofibers were prepared by electrospinning and forcespinning methods. The bioactive components, which were used to functionalize the prepared dressings, were plant extracts, clotrimazole, ampicillin, lysozyme, and proteolytic enzymes. The theoretical part is focused on the description of the use of nanofibrous and non-fibrous materials in medicine, characterization of materials for the production of wound dressings and bioactive components. Furthermore, this section describes the methods used to prepare and characterize wound dressings. In the practical part were prepared aqueous and oil extracts from selected plants. Extracts were characterized for polyphenols content and antioxidant activity. PHB-based nanofibers were prepared using electrospinning and forcepinning methods. Nanofibers were enriched with selected plant oil extracts and clotrimazol. Modified nanofibres were detemined for antioxidant activity, short-term and long-term stability. Non-fibrous wound dressings were prepared from alginate and chitosan. These dressings were functionalized by the addition of selected aqueous extracts, ampicillin, lysozyme, papain, bromelain, and collagenase. Non-fibrous wound dressings were determined for antioxidant activity, short-term stability and proteolytic activity. The prepared wound dressings were tested for their antimicrobial effects on cultures of Micrococcus luteus, Serratia marcescens, Staphylococcus epidermidis and Escherichia coli. In conclusion, successfully prepared bioactive wound dressings with antioxidant and antimicrobial agents were tested for safety on human cells. The determination was performed using the MTT cytotoxicity test on human keratinocytes.

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Assis, Maria Angélica de Sá. "Ação antimicrobiana e citotoxicidade de extratos aquoso e glicólico de própolis sobre bactérias anaeróbias de importância odontológica /." São José dos Campos, 2018. http://hdl.handle.net/11449/180563.

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Orientador: Luciane Dias de Oliveira
Banca: Luis Felipe das Chagas e Silva de Carvalho
Banca: Jônatas Rafael de Oliveira
Resumo: As plantas medicinais e os fitoterápicos têm sido utilizados como coadjuvantes e alternativos no combate a diversas doenças com crescente frequência, no entanto, na Odontologia seu uso ainda é bastante limitado. Com isso, o objetivo deste estudo é avaliar a ação antimicrobiana dos extratos aquoso e glicólico de própolis verde sobre micro-organismos anaeróbios de interesse odontológico, bem como sua citotoxicidade, a fim de introduzir e incentivar o uso efetivo e sistemático desse fitoterápico em produtos como dentifrícios e enxaguatórios bucais no combate a cáries e doenças periodontais. Os extratos comerciais aquoso e glicólico de própolis foram obtidos das empresas Apis Flora e Mapric, respectivamente. Para avaliação da atividade antimicrobiana foram utilizadas cepas-padrão (ATCC) de Fusobacterium nucleatum, Parvimonas micra, Porphyromonas endodontalis Porphyromonas gingivalis e Prevotella intermedia em cultura planctônica, verificando a concentração inibitória mínima e concentração microbicida mínima (CIM e CMM), segundo Clinical and Laboratory Standards Institute. Para biofilmes monotípicos, suspensões padronizadas (107 céls/mL) foram adicionadas em poços de microplacas e após 48 h em anaerobiose foram tratados com 3 concentrações do extrato de própolis (n=12) por 5 min. Foi incluído um controle positivo (solução fisiológica) e um controle negativo (clorexidina). O biofilme foi mensurado pelos testes MTT e Cristal Violeta. Para análise de citotoxicidade, queratinócitos hu... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Medicinal plants and herbal medicines have been used as adjuvants and alternatives in fighting various diseases with increasing frequency. However, in dentistry its use is still quite limited. Therefore, the objective of this study is to evaluate the antimicrobial action of the aqueous and glycolic extracts of green propolis on anaerobic microorganisms of dental interest, in order to introduce and encourage the effective and systematic use of this herbal medicine in products such as dentifrices and mouthwashes in the fight against tooth decay and periodontal diseases. Aqueous and glycolic commercial extracts of propolis were obtained from Apis Flora and Mapric companies, respectively.To evaluate the antimicrobial activity, standard strains (ATCC) of Fusobacterium nucleatum, Parvimonas micra, Porphyromonas endodontalis, Porphyromonas gingivalis, and Prevotella intermedia in planktonic culture was used, verifying the minimum inhibitory concentration and minimum microbicide concentration (MIC and CMM), according to Clinical and Laboratory Standards Institute. For monotypic biofilms, standardized suspensions (107 cells / mL) was added to microplate wells and after 48 h in anaerobiosis was treated with 3 concentrations of propolis extracts (n = 12) for 5 min. A positive control (saline solution) and a negative control (chlorhexidine) was included. The biofilm was measured by the MTT and Violet Crystal tests. For cytotoxicity analysis, human keratinocytes (HaCaT) were cultured and ... (Complete abstract click electronic access below)
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Akter, Raushanara. "Isolation and Structural Elucidation of Bioactive Compounds from Bangladeshi Medicinal Plants with a Focus on Novel Anticancer Compounds." Thesis, Griffith University, 2014. http://hdl.handle.net/10072/366507.

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The present study describes the bioactivity guided isolation and structural elucidation of novel anticancer compounds from the Bangladeshi medicinal plant Blumera lacera. At the outset nineteen Bangladeshi medicinal plants were selected and collected from different parts of Bangladesh. Plants underwent preliminary cytotoxicity screening based on their traditional medicinal uses, limited previous research on them, and their availability. The selected plants were extracted with methanol and screened for their cytotoxic potential using the MTT assay against two healthy cell lines (mouse fibroblast (NIH3T3), a healthy monkey kidney (VERO)) and four cancer cell lines namely, gastric (AGS), colon (HT-29), two breast (estrogen-dependent: MCF-7 and estrogen non-dependent: MDA-MB-231). Preliminary cytotoxicity assessment led to the identification of seven plants with significant cytotoxic potential, having IC50 < 1.0 mg/mL against a minimum of one cancer cell line. The identified plants were: Avicennia alba, Caesalpinia pulcherrima, Diospyros peregrina, Ecbolium viride, Jasminum sambac, Clitoria terantea, and Saraca asoca. The bioactivity detected correlated with their traditional uses as anticancer agents. Comparing cytotoxicity effects of the selected plants with that of Blumea lacera which was previously screened for cytotoxic potential in our research lab, Blumea lacera was found to be more cytotoxic and thus selected for bioassay-guided isolation of constituents.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Pharmacy
Griffith Health
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Uzu, Gaëlle. "Spéciation, transfert vers les végétaux et approche toxicologique des émissions atmosphériques d'une usine de recyclage de plomb." Thesis, Toulouse, INPT, 2009. http://www.theses.fr/2009INPT008A/document.

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Depuis la révolution industrielle en Europe (XIXe siècle), les nombreuses activités anthropiques ont provoqué des changements environnementaux globaux considérables. La composition de l'atmosphère terrestre en particulier, a été fortement modifiée par l'émission de polluants gazeux et particulaires. Actuellement, l'industrie métallurgique de seconde fusion contribue de façon significative aux émissions atmosphériques de métaux. C'est pourquoi ce travail de thèse s'est focalisé sur l'étude des transferts et impacts sur les sols, les végétaux et l'homme, des particules émises par le procédé de recyclage du plomb en relation avec leurs propriétés physico-chimiques. Trois sources principales d'émissions de particules ont été identifiées dans le procédé du recyclage du plomb et caractérisées en vue d'étudier les impacts potentiels sur les cibles végétales et humaines. Les particules échantillonnées (postes de travail et émissions canalisées) et ségréguées en fonction de leur taille (PMtot, PM10 et PM2,5) sont principalement composées de métaux (jusqu'à 50% en masse de la composition totale en métaux de transition, alcalins et alcalino-terreux), avec une majeur partie de plomb (25-45 %). Les spéciations majoritaires du plomb sont la galène (PbS), le sulfate du plomb (PbSO4) ou dérivés (xPbO.PbSO4 x=1,2 ou 3). L'étude du transfert des particules dans le sytème sol-plante a montré que, lorsque la taille des particules de process présentes dans le sol diminue (de 10µm à 2.5µm), le tranfert du plomb vers les parties aériennes des salades augmente de 20%. Le transfert foliaire de plomb issu des particules de process a été mis en évidence et des mécanismes d'absorption.ont été proposés. Enfin, l'étude exploratoire des particules riches en plomb sur la santé humaine a permis de montrer que la diminition de la taille des particules ingérées augmentait la bioaccessibilité gastrique du plomb. Dans le cas de l'inhalation, il a été démontré que les particules n'induisaient pas de cytotoxicité jusqu'à 50µg/cm2, mais provoquaient une réponse inflammatoire dose-dépendante des cellules épithéliales pulmonaires
Since the Industrial Revolution in Europe (XIXe century), human activities have caused significant global environmental changes. The composition of the atmosphere in particular, has been extensively modified by the emission of gaseous and particulate pollutants. Currently, the secondary (or recycling) metallurgical industry contributes significantly to air emissions of metals. Therefore, this thesis focused on the study of transfers and impacts on soils, plants and humans, of particles from the recycling process of lead in relation to their physicochemical properties. Three main sources of particulate emissions have been identified in the process of recycling lead and characterized, to study the potential impacts on plant and human targets. The particles sampled (workstations and channelled emissions), and segregated according to their size (PMtot, PM10 and PM2, 5), are mainly composed of metals (up to 50% by weight of the total composition in transition metals alkaline and alkaline), with a major part of lead (25-45%). The major speciations of lead are galena (PbS), lead sulfate (PbSO4) or derivatives (xPbO.PbSO4 x = 1,2 or 3). The study of transfer of particles in the soil-plant system has shown that when the particle size of processes in the soil decreases (from 2.5µm to 10µm), the transfer of lead into the aerial parts of lettuce growing at 20 %. The uptake of lead from particles process by leaves has been demonstrated and mechanisms of absorption have been proposed. Finally, exploratory study of lead-rich particles on human health has shown that diminution of the size of particles ingested increased gastric bioaccessibility of lead. In the case of inhalation, it was shown that the particles did not induce cytotoxicity up 50µg/cm2, but caused a dose-dependent inflammatory response of lung epithelial cells

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Miller, Andrew B. "Antimicrobial and Anticancer Activity of Essential Oils from Guatemalan Medicinal Plants." BYU ScholarsArchive, 2010. https://scholarsarchive.byu.edu/etd/2411.

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Guatemalan medicinal plants were collected and screened for the presence of essential oils using steam distillation. Oil was found in 63 species from 24 families and was tested in tube dilution assays for activity against Escherichia coli, Staphylococcus aureus, Streptococcus mutans, Lactobacillus acidophilus and Candida albicans. Several essential oils were highly active with 20 instances of oils inhibiting the microbes at an MIC of 0.31 µl/ml. Oils were also tested against cancerous and established cell lines using a 15% (v/v) agar-media which was developed to improve essential oil solubility. Assays were performed against three cancer lines: Stomach (AGS: CRL-1739), Skin (A375: CRL-1619), Tongue (CAL27: CRL-2095) and an established Monkey Kidney cell line (Vero C 1008: CRL-1586). Assessment of viability was performed using the Neutral Red assay with results indicating that many of the oils significantly inhibited cancer cell lines in vitro with 24 individual instances producing an IC50 of 0.20 µl/ml or less. Therapeutic indices indicated that many of the highly inhibitory oils were more cytotoxic to cancerous cell lines than to the established cell line.

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Marques, Milene Bueno. "Triagem fitoquímica e avaliação da sensibilidade antimicrobiana e da genotoxicidade de Sedum praealtum DC. (Bálsamo)." Universidade Jose do Rosario Vellano, 2015. http://tede2.unifenas.br:8080/jspui/handle/jspui/102.

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Made available in DSpace on 2016-05-02T13:55:21Z (GMT). No. of bitstreams: 1 Milene Bueno Marques-Dissertacao.pdf: 825475 bytes, checksum: cd33a50c8ba95cbc3e9504abcf1d976c (MD5) Previous issue date: 2015-02-25
Sedum praealtum DC. (Crassulaceae) is one of 350 species pharmacologically active from the genus Sedum, whose actions in treatment of eyes (pain and swelling) and ulcer, inflammatory problems, as contraception and anti-fertilization, antinociceptive and anti-inflammatory have been reported. The objective was to evaluate the hydroethanolic extract of S. praealtum regarding their potential antimicrobial in vitro (some bacteria, yeasts and micobactéria strains), cytotoxic in vitro and genotoxic in vivo. A fast phytochemical screening of this extract was also performed. The antimicrobial activities were carried out by microdilution in broth and agar diffusion methods (CLSI). The genotoxic effects and systemic toxic and cytotoxicity were evaluated by micronucleus assay in mice bone marrow and cell cultures of Aedes albopictus, respectively. The selectivity index was also established (SI = CI50/MIC). Dosages of flavonoids and phenolic compounds were done by colorimetric and precipitation techniques. A high amount of phenolic compounds were identified in S. praealtum root. The S. praealtum leaves showed broad spectrum of action and variables MICs: Gram-negative bacteria (E. aerogenes, E. coli, P. aeruginosa, P. mirabilis, S. marcescens and S. typhimurium), gram-positive (B. cereus, B. subtilis, E. faecalis, M. luteus and S. aureus) and yeast (S. cerevisiae). The stem and root were restricted to gram-positive bacteria and S. cerevisiae, other than E. coli (stem) and P. mirabilis (root) microbicidal action microorganism- and anatomical part-dependent (leaf, stem or root). S. praealtum showed no inhibition against C. albicans, M. tuberculosis and M. bovis. The root showed acceptable SI (SI  1) for P. mirabilis; B. subtilis; B. cereus; M. luteus; E. faecalis; S. aureus and S. cerevisiae, whereas the sheet only for S. cerevisiae. The hydroalcoholic extract of S. praealtum leaves revealed no genotoxic effects (no clastogeny and/or aneugeny) and toxicity in bone marrow of mice, dose (0.5-2 g.Kg-1) and time-independent (24-48 hours), but sex-dependent (male and female). This was the first scientific study of this nature involving S. praealtum and partially the results provide a theoretical basis for comprehensive development and utilization of plant resources. However, advanced phytochemical characterization together with the various pharmacological and pharmacogenomic studies should be conducted in order to characterize their effects and, importantly, for the establishment of limits for human consumption, the delineation of potential risks to human health, and for rational strategies for implementing chemo-preventive measures.
Sedum praealtum DC. (Crassulaceae) é uma das 350 espécies farmacologicamente ativas do gênero Sedum, cujas ações no tratamento dos olhos (dores e inchaços) e úlcera, de problemas inflamatórios, como contraceptivo e antifertilização, antinociceptiva e anti-inflamatória foram relatadas. O objetivo foi avaliar o extrato hidroetanólico de S. praealtum quanto aos seus prováveis potenciais antimicrobiano in vitro de algumas cepas de bactérias, de leveduras e de micobactérias, citotóxico in vitro e genotóxico in vivo. Uma rápida triagem fitoquímica desse extrato também foi realizada. As atividades antimicrobianas foram realizadas empregando-se os métodos de microdiluição em caldo e em difusão em agar (CLSI). Os efeitos genotóxicos e tóxicos sistêmicos e a citotoxicidade foram avaliados pelo ensaio do micronúcleo na medula óssea de camundongos e pelas culturas celulares de Aedes albopictus, respectivamente. O índice de seletividade também foi estabelecido (IS = CI50/CIM). Dosagens de flavonoides e compostos fenólicos foram feitas usando técnicas colorimétricas e de precipitação. Uma elevada quantia de compostos fenólicos foi identificada na raiz de S. praealtum. As folhas de S. praealtum mostraram ação de amplo espectro e CIM variáveis: bactérias gram-negativas (E. aerogenes, E. coli, P. aeruginosa, P. mirabilis, S. marcescens e S. typhimurium), gram-positivas (B. cereus, B. subtilis, E. faecalis, M. luteus e S. aureus) e levedura (S. cerevisiae). O caule e a raiz foram restritos às bactérias gram-positivas e S. cerevisiae, exceto E. coli (caule) e P. mirabilis (raiz) ação microbicida micro-organismo-dependente e parte anatômica-dependente (folha, caule ou raiz). S. praealtum não apresentou ação contra C. albicans, M. tuberculosis e M. bovis. A raiz mostrou IS aceitável (IS  1) para P. mirabilis; B. subtilis; B. cereus; M. luteus; E. faecalis; S. aureus e S. cerevisae, enquanto que a folha apenas para S. cerevisae. O extrato hidroalcoólico das folhas de S. praealtum revelou efeitos não genotóxicos (ausência de clastogenia e/ou aneugênia) e efeitos tóxicos na medula óssea de camundongos, dose- (0,5-2 g.Kg-1) e tempo-independente (24-48h), porém sexo-dependente (macho e fêmea). Este foi o primeiro estudo científico dessa natureza envolvendo S. praealtum e, parcialmente, os resultados fornecem uma base para a utilização e para o desenvolvimento compreensivo de recursos vegetais. Todavia, a caracterização fitoquímica avançada aliada aos diversos estudos farmacológicos e farmacogenômicos deveriam ser conduzidos a fim de caracterizar os seus efeitos e, mais importante, estabelecer limites para o consumo popular, delinear os riscos potenciais à saúde humana, e implementar estratégias racionais e medidas quimio-preventivas.

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Sekhoacha, Mamello. "Antimalarial activity and cytotoxicity of some South African medicinal plants and their active constituents." Doctoral thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/3300.

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Deng, Ye. "Bioactive Constituents of Two Medicinal Plants from Indonesia." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1274289346.

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Janse, van Rensburg Catharina Scholtz. "In vitro evaluation of antioxidant properties of Rosa roxburghii plant extract / Catharina Scholtz Janse van Rensburg." Thesis, North-West University, 2003. http://hdl.handle.net/10394/191.

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Rosa roxburghii, also known as "Burr Rose" or "Chestnut Rose", originated in southwest China and was introduced to the botanic garden in Calcutta around 1824. It was named after William Roxburgh who was the superintendent. The extract of fruit of the Rosa roxburghii plant is the base ingredient of a range of products that is commercially sold under the Cili Bao label. The extract is composed of a wide range of substances of nutritional value, in particular a relatively high amount of antioxidants such as ascorbate and plant phenols. It has been reported before that supplementation with the fruit extract resulted in increased red blood cell superoxide dismutase, catalase and the reduced form of glutathione. An enhancement of the antioxidant status could contribute to the protection against several diseases where oxidative stress is a major factor in the pathology, such as atherosclerosis, cancer and immunity stress. Several anecdotal reports with little (published) scientific support claim that human supplementation of the Rosa roxburghii extract to the diet has a protective effect against several diseases, including the above mentioned. Medicinal and herbal plants are used in large sections in developing countries for primary care and there is now also an increase in the use of natural therapies in developed countries. However, plant extracts can also consist of anti-nutritional and possible toxic components, such as oxalic acid and nitrates, which could express cytotoxic and genotoxic activities. Therefore, understanding the health benefits but also the potential toxicity of these plants is important. The objective of this study was to investigate the beneficial properties of Rosa roxburghii extract from an antioxidant potential perspective and in particular to investigate the safety of the product for human consumption. For this purpose in vitro evaluation of the cellular toxicity, mutagenicity and genotoxicity was performed. In addition, specific biochemical parameters relating to the antioxidant status of the product, i.e. antioxidant capacity, oxidative stress prevention and glutathione redox state profiles were investigated in vitro as well as in vivo. The results indicated that Rosa Roxburghii fruit extract was not mutagenic when tested with Salmonella typhimurium strains TA 98, TA 100 and TA 102 in the Ames test. The results, however, pointed towards an antimutagenic effect of the extract in these strains against metabolic activated mutagens 2- acetylaminoflurorene (2-AAF) and aflatoxin B1, and the direct-acting mutagen, methanesulfonate (MMS). In primary rat hepatocyte, Rosa roxbughii extract did not elicit double or single strand DNA damage and cell viability loss using the single cell gel electrophoresis (Comet assay), lactate dehydrogenase leakage test or the mitochondria1 conversion test of MTT to formazan (MTT test). Again the opposite effect was observed: pre-treatment of hepatocytes with Rosa roxbughii extract significantly reduced the effect of oxidative stress-induced cellular- and genotoxicity. These results point to a protective effect against oxidative stress which is reflected in an increase of the antioxidant capacity and glutathione redox state (GSH/GSSG) in vitro (lymphoblasts) and in vivo (humans) reported in this study. This study underlines the previously suggested potential of this plant extract as a natural and safe antioxidant supplement.
Thesis (M.Sc. (Biochemistry))--North-West University, Potchefstroom Campus, 2004.

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Maja, Matshidiso Patricia. "In Vitro cytotoxicity and antibacterial activity of selected South African medicinal plants used in the treatment of periodontitis." Diss., University of Pretoria, 2009. http://hdl.handle.net/2263/24855.

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The use of medicinal plants in the treatment of infectious diseases is an acceptable and popular phenomenon in South Africa and worldwide. The potential of extracts from these plants as antimicrobial agents necessitates their scientific evaluation. Therefore, this study evaluated the antimicrobial activity of Carpobrotus edulis; Cotyledon orbiculata; Datura stramonium; Dodonaea angustifolia; and Zanthoxylum capense against Porphyromonas gingivalis; Tannerella forsythensis and Actinobacillus actinomycetemcomitan. Given that most currently used drugs are cytotoxic, the possible cytotoxic effect of these medicinal plants on human periodontal ligaments fibroblasts and human gingival fibroblasts was also determined. The modified broth micro dilution method incorporating resazurin as an indicator of cell growth in 96-well microtitre plates was used to determine the antibacterial activity of the test plants extracts. The extracts showed some significant antibacterialactivity against Porphyromonas gingivalis, Tannerella forsythensis and Actinobacillus actinomycetemcomitans. The activity varied with respect to individual test bacteria. Their minimum inhibitory concentration (MIC) values ranged from 10 to 0.01mg.mr-l. All bacteria tested were inhibited by the highest concentration of the selected plant extracts ( 1 Omg.ml-1). The MTT [3-( 4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] method was used to determine the cytotoxic effect of test extracts. All extracts tested with the exception of Carpobrotus edulis, inhibited the growth of both human periodontal ligament fibroblasts and human gingival fibroblasts at the tested dilutions, with the cytotoxicity levels being directly related to the concentration of the extracts. The extract of Carpobrotus edulis, inhibited the tested cells at 10-1 for human periodontal ligaments fibroblasts and ≥ 2: 10-2 for human gingival fibroblasts. All other tested concentrations of Carpobrotus edulis extracts enhanced the growth of both human periodontal ligaments and human gingival fibroblasts. The study provided a scientific evidence of the important role that medicinal plants play as antibacterial agents in the treatment of oral infections.
Dissertation (MSc)--University of Pretoria, 2009.
Community Dentistry
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Uddin, Shaikh Jamal. "Cytotoxicity Screening of Bangladeshi Medicinal Plants and Isolation and structural Elucidation of Novel Anti-Cancer Compounds from Acrostichum aureum." Thesis, Griffith University, 2011. http://hdl.handle.net/10072/365889.

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This thesis describes the cytotoxicity and phytochemical screening of 16 selected medicinal plants collected from the tidal forests of the coastal Sundarban and locations within the Khulna district of Bangladesh. The selected plants were successively extracted with n-hexane, dichloromethane, methanol and water. The methanol and aqueous extracts were then screened for cytotoxic activity (MTT assay) against one normal mouse fibroblast and three human cancer cell lines (gastric, colon and breast cancer). The results supported some of the traditional uses and reported cytotoxic activity for some of these plants. It identified some plant extracts (Hygrophila auriculata, Hibiscus tiliaceous and Limnophila indica) with selective cytotoxic activity to cancer cells (IC50 1.1 - 1.6 mg/mL) but non-toxic to normal mouse fibroblast cells. Some extracts (Acrostichum aureum, Ammannia baccifera, Argemone mexicana, Limnophila indica, Clerodendron inerme, Cynometra ramiflora and Xylocarpus moluccensis) showed low cytotoxicity against mouse fibroblast (IC50 > 2.5 mg/mL) but selective potent toxicity against cancer cells (IC50 0.2 - 2.3 mg/mL). Four extracts (Adiantum caudatum, Hibiscus tiliaceous and Blumea lacera) showed cytotoxic activity against all the cell lines tested in the study. The methanolic and aqueous extracts of B. lacera were identified as having the most potent cytotoxic activity against all cell lines with IC50 0.01 - 0.08 mg/mL. Reversed-phase analytical HPLC profiling of all extracts was carried out with extracts, demonstrating low toxicity against normal mouse fibroblast cells, but selective high toxicity against the three cancerous cell lines (A. aureum and A. baccifera) and highest toxicity against all the cell lines (B. lacera). Extracts from these plants were further investigated by LC-MS. A. aureum was then selected and further investigated with one compound subsequently being isolated from n-hexane fraction and twelve compounds from the methanolic fraction. Three compounds were identified as novel natural products, namely (2'Smethylhexyl) (2''S-methyl-5''-acetylpentyl) phthalate (1), (2R, 3S)-sulfated pterosin C (2) and (2S, 3S)-sulfated pterosin C (5).
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Pharmacy
Griffith Health
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14

Babajide, Jelili Olalekan. "Chemical and biological investigation into some selected African indigenous medicinal plants." Thesis, University of the Western Cape, 2009. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_7625_1297404173.

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African medicinal plants are commonly used throughout Africa to treat a variety of ailments including wounds and ulcers, cough and chest complaints, gingivitis, fever and gonorrhoea, indication all related to infection and inflammation. In screening several plant species from an inventory of common medicinal plants from both South and West Africa for diverse medicinal purposes, 6 plants were selected because of their interesting and useful ethnomedicinal values.

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Odeyemi, Samuel Wale. "A comparative study of the in vitro antidiabetic properties, cytotoxicity and mechanism of action of Albuca bracteata and Albuca setosa bulb extracts." Thesis, University of Fort Hare, 2015. http://hdl.handle.net/10353/3154.

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The search for cheap, non toxic and readily available antidiabetic drugs has been a challenge for researchers and the pharmaceutical industries. Diabetes mellitus is a metabolic disease characterized by defects in the synthesis of insulin and/or insensitivity to the action of insulin at the target cells. The disease has been on the increase mostly in developing countries where large proportions of the population have little access to good medical care due to either accessibility or non availability of synthetic drugs. This has led to the use of medicinal plants to treat diabetes because it is safe, cheap and with few side effects. There is little scientific evidence on the dosages, active compounds, mechanisms of action and toxicity of these traditionally used plants. Two of the most frequently used plants; Albuca setosa and Albuca bracteata were investigated in this study. The qualitative analysis of different extractions of these plants revealed the presence of phenolics, alkaloids, tannins and saponins. The antioxidant properties of aqueous, acetone and methanollic extracts of Albuca setosa and Albuca bracteata were investigated using models such as Diphenyl-1-Picrylhydrazyl (DPPH), 2, 2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), Ferric ion reducing antioxidant potential (FRAP), Nitric Oxide and Hydrogen Peroxide (H2O2). Both plants revealed inhibitions against DPPH in a concentration - dependent manner with Albuca setosa (0.330 mg/ml) showing higher activity than Albuca bracteata (0.647 mg/ml) determined from the IC50. The aqueous extract of Albuca setosa showed a higher inhibition against DPPH radical compared to the Albuca bracteata aqueous extract at all concentrations investigated. The isolated saponins from Albuca bracteata had a higher DPPH scavenging activity than the crude methanolic extract of the plant in a concentration - dependent manner but are significantly different from each other at 0.4, 0.6 and 1.0 mg/ml only. The IC50 of the saponins was also observed to be higher than the crude extracts and standards.The Albuca setosa aqueous extract showed a higher percentage inhibition of ABTS radicals than Albuca bracteata at all the concentrations investigated. Overall, the Albuca setosa aqueous extract (0.0809 mg/ml) showed maximum activity against ABTS radicals. The iron reducing power was significantly higher (P < 0.05) in the methanolic extract of both plants compared to the aqueous counterpart. Overall, the Albuca bracteata aqueous extract (0.344 mg/ml) showed maximum activity as indicated by the IC50. The aqueous extracts of both plants also revealed percentage inhibitions in a concentration - dependent manner against NO2. The aqueous extract of Albuca bracteata bulb was more active against nitric oxide and hydrogen peroxide inhibition. In this study, the cytotoxicity of the extracts was evaluated at a high dose of 100 μg/ml on Chang liver cells and determined using MTT, crystal violet, glucose consumption, lactate production and lactate dehydrogenase release and FRAP. The aqueous extracts of both Albuca setosa and Albuca bracteata were non-toxic on Chang liver cells at the concentrations investigated. The MTT revealed that the aqueous extract of Albuca setosa bulb had the optimum cell viability of 108.09 percent while the acetonic extract of Albuca bracteata showed the least cell viability (37.72 percent) compared with the control. The crystal violet test also revealed the acetone extract of Albuca bracteata to have the least percentage of cell viability at 31.47 percent, while the aqueous extract of Albuca setosa showed the maximum cell viability at 112.5 percent. The aqueous extracts of both plants showed higher percentage cell density on the second day of incubation from the proliferation assay. All the tested samples were observed to consume more glucose than the blank except for the methanollic and acetone extracts of Albuca bracteata bulb. The aqueous and methanolic extracts of Albuca setosa bulbs produced the highest lactate with 120.2 μg/ml and 113.7 μg/ml respectively. The acetone extracts of both Albuca setosa and Albuca bracteata revealed toxicity with a higher lactate dehydrogenase release compared to the control.

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Pimentel, Vanessa Nascimento. "Liquen plano oral e doença do enxerto contra o hospedeiro cronica da mucosa oral = analise histologica e imuno-histoquimica." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/311046.

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Orientador: Maria Leticia Cintra
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: O líquen plano oral (LPO) e o acometimento oral da doença do enxerto contra o hospedeiro crônica (DECHc) apresentam características clínicas e histológicas semelhantes, apesar da etiologia distinta. A apoptose, induzida por linfócitos T citotóxicos, tem sido proposta como o tipo de morte dos ceratinocitos, em ambas as doenças. A citotoxidade celular é mediada, dentre outros mecanismos, por grânulos contendo granzima B e perforina. Poucos trabalhos foram desenvolvidos demonstrando o papel destas moléculas no líquen plano; dentre estes, alguns estudaram a interação das células que expressam estas moléculas com os demais componentes do infiltrado. Contudo, há raros estudos sobre este tema na DECHc. Considerando que as características em comum podem refletir similaridades nos mecanismos imunológicos, o objetivo do nosso estudo foi correlacionar os achados morfológicos e imuno-histoquímicos do LPO e da DECHc oral, na tentativa de compreender melhor a patogênese destas doenças. Foram analisadas 29 amostras de LPO e 27 de DECHc oral, coletadas no período de 1994 a 2007, de pacientes atendidos no Hospital das Clínicas e na Unidade de Transplante de Medula Óssea da UNICAMP. Novos cortes foram corados por H&E e pela técnica imuno-histoquímica para CD4, CD8, MAC 387, ICAM-1, granzima B e perforina. O número de células CD4-positivas foi estatisticamente maior no LPO do que na DECHc (p<0,0001), enquanto as médias totais (do epitélio + do tecido conjuntivo) de células positivas para granzima B e perforina foram maiores na DECHc que no LPO (p<0,05). Foi observado também que, quanto maior o número de células perforina+, maior era o número de células granzima B+, tanto no epitélio como no tecido conjuntivo, nos dois grupos de doenças (p<0,05). No LPO, o número de corpos apoptóticos isolados mostrou uma correlação positiva com a granzima B e negativa com a perforina do tecido conjuntivo (p<0,01). Inversamente, nas lesões orais da DECHc, o número de corpos apoptóticos agrupados apresentou uma correlação positiva com a perforina do tecido conjuntivo. Não houve diferença entre o LPO e a DECHc oral com relação ao número de corpos apoptóticos (isolados ou agrupados), nem quanto à extensão da degeneração hidrópica da camada basal, e nem mesmo com relação ao número de células imunomarcadas para CD8, ICAM-1 e MAC 387. Estes achados indicam que a apoptose, no LPO, parece correlacionar-se com a ação da granzima B, enquanto que, na DECHc oral, a perforina parece ser mais atuante. Embora o LPO e a DECHc oral apresentem similaridades clínicas e histológicas, parece haver diferenças na patogênese destas doenças. Os resultados encontrados podem ser úteis para aprimorar a compreensão dos mecanismos imunológicos, bem como podem embasar o desenvolvimento de novas estratégias terapêuticas para o controle da apoptose e redução da morbidade associada a estas doenças.
Abstract: Oral lesions in lichen planus (OLP) and chronic graft-versus-host disease (cGVHD) have similar clinical and histological features, but distinct etiology. Apoptosis induced by cytotoxic T lymphocyte has been proposed as the form of keratinocytes death. The cell cytotoxicity is mediated, among other mechanisms, by granules containing granzyme B and perforin. Few studies have been published showing the role of those molecules in lichen planus, as well as their relationship with other inflammatory infiltrate components. However, rare works were reported about this theme in cGVHD. Since common features can reflect similarities in immunological mechanisms, the purpose of our study was to correlate the morphological and immunohistochemical findings of OLP and cGVHD to better understand the pathogenesis of these diseases. We analyzed 29 samples of OLP and 27 of oral cGVHD collected in the period between 1994 and 2007, from patients treated at the University Hospital and Bone Marrow Transplant Unit of UNICAMP. Additional sections were obtained and stained for H&E and immunohistochemical technique targeting CD4, CD8, MAC 387, ICAM-1, perforin and granzyme B. The number of CD4-positive cells number was significantly higher in OLP than in cGVHD (p<0,0001), while the total means (epithelium plus connective tissue number) of the granzyme B- and perforin-positive cells were significantly higher in cGVHD (p<0,05). Also, it was found that the higher the number of perforin+ cells, the higher the number of granzyme-B + cells in the epithelium and in the connective tissue for both groups (p<0.05). In OLP, the number of single apoptotic bodies had a positive correlation with connective tissue granzyme B immunostaining and a negative correlation with perforin (p<0.01). On the contrary, in oral cGVHD, the number of apoptotic body clusters presented a positive correlation with connective tissue perforin (p<0.01). Our findings indicate that apoptosis in OLP seems to be correlated with granzyme B release, while in oral cGVHD, perforin seems to be more important. There were no significant differences between OLP and cGVHD oral regarding the following features: the amount of apoptotic bodies (isolated o clusters), the extension of hydropic basal cell degeneration, and the number of positive cells for CD8, ICAM-1 and MAC-387. These results indicate that apoptosis, in OLP, seems to correlate with granzyme B release while, in oral cGVHD, perforin is preponderant. Although OLP and oral cGVHD present clinical and histological similarities, differences seem to exist in the athogenesis of these diseases. Our results might help to better understand the immunological mechanisms of these two conditions, as well as supporting the development of new therapeutic strategies for controlling apoptosis and reducing morbidity associated with them.
Mestrado
Anatomia Patologica
Mestre em Ciências Médicas

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17

Monteiro, Maria Cristina. "Cytogenotoxicity of chromium and cadmium in plants and in human cells." Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/18613.

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Doutoramento em Biologia
Os metais têm sido alvo de preocupação devido à sua persistência no ambiente e potencial toxicidade para os seres vivos, após a atividade humana desmensurada. Nesta tese é dada relevância ao Cr e ao Cd, considerados metais poluentes prioritários. Assim, o objetivo do trabalho foi avaliar e compreender os efeitos cito- e genotóxicos putativamente induzidos por sais de Cr e Cd em plantas e células humanas. O Capítulo 1 expõe as fontes de poluição de Cr e Cd, os seus efeitos tóxicos para os seres vivos e mecanismos de absorção a nível celular em plantas e humanos. Os biomarcadores mais usados na avaliação de exposição e toxicidade de metais foram brevemente discutidos, assim como a possibilidade de realização de ensaios in vivo e in vitro. Dois modelos biológicos foram escolhidos para avaliação da toxicidade do Cr e Cd: a alface (Lactuca sativa L.) e osteoblastos humanos, considerados alvos de acumulação e toxicidade destes metais. Além disso, os efeitos cito- e genotóxicos do Cr e Cd não estavam esclarecidos nos modelos biológicos utilizados. Assim, no Capítulo 2 foram avaliados os efeitos cito- e genotóxicos do Cr e Cd em alface in vivo, enquanto o Capítulo 3 abordou as mesmas questões em osteoblastos humanos in vitro. Cada estudo envolveu a compreensão e integração dos mecanismos de cito- e genotoxicidade em ambos os modelos biológicos em resposta à exposição aos metais. Finalmente, na última secção – Capítulo 4, é apresentada uma conclusão geral, considerando os resultados obtidos para ambos os metais e modelos biológicos e trabalhos futuros relativos aos efeitos e níveis de toxicidade descritos ao longo do trabalho.
Metals have been a major concern regarding their persistence in the environment and potential toxicity to living organisms, after immoderate human activity. In this thesis, it is given relevance to Cr and Cd which are among the priority metal pollutants. Therefore, the aim of this work was to evaluate and understand putative cyto- and genotoxic effects induced by Cr and Cd salts in plants and human cells. In Chapter 1, it is described the source of Cr and Cd pollution, toxic effects to living organisms, and mechanisms of metal uptake at the cellular level, in plants and humans. Briefly, the most used biomarkers in metal exposure and toxicity assessment were discussed as well as in vivo and in vitro testing. Two biological models were chosen for toxicity assessment of Cr and Cd: lettuce (Lactuca sativa L.) and human osteoblasts, both considered targets of these metals accumulation and toxicity. Moreover, the cyto- and genotoxic effects of Cr and Cd had not yet been clarified in both biological models used. Therefore, Chapter 2 begins to address the cyto- and genotoxic effects of Cr and Cd in lettuce in vivo, while Chapter 3 takes over these issues in human osteoblasts in vitro. Each of these studies involved an understanding and integration of the mechanisms of cyto- and genotoxicity in both biological models in response to metal exposure. Finally, over the last section – Chapter 4, a global conclusion is raised considering the results obtained for both metals and biological models, and future work on the effects and levels of toxicity presented along this work are also included in these final remarks

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18

Khiralla, Afra. "Études phytochimique, cytotoxique et antibactérienne de champignons endophytes issus de plantes médicinales du Soudan." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0159/document.

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Pour la première fois, l’étude de la flore fongique endophytique de cinq plantes médicinales soudanaises : Calotropis procera (Ait.), Catharanthus roseus (L.), Euphorbia prostrata (Ait.), Trigonella foenum-graecum (L.), and Vernonia amygdalina (Del.) a été réalisée. Un total de 23 souches de champignons endophytes ont été isolées à partir des plantes après la stérilisation de surface puis les différentes analyses biologiques ont été effectuées. Les extraits bruts d’acétate d’éthyle de 21 endophytes ainsi que de leurs plantes hôtes ont été évalués pour leur teneur en phénols totaux et leur activité antioxydante en utilisant respectivement la méthode colorimértrique Folin-Ciocalteu et le piégeage des radicaux libres par la méthode 1,1,-diphényl-2-picrylhydrazil (DPPH) in vitro. Une évaluation générale de la cytotoxicité de 16 endophytes sélectionnés ainsi que de leurs plantes hôtes a été réalisée selon le test MTT sur trois types de cellules cancéreuses : carcinome du sein humain (MCF7), adénocarcinome du côlon (HT29 et HCT116). Ces extraits ont été aussi testés, selon la méthode de dilution en bouillon, sur deux souches bactériennes représentatives, Escherichia coli et la souche résistante à la méthicilline de Staphylococcus aureus. La teneur en phénols totaux (89,9 ±7,1 mg Equivalent d’Acide Gallique EAG/g) ainsi que l’activité antioxydante (IC50: 18±0,1 µg/mL) les plus élevées ont été observées pour l’endophyte, Aspergillus terreus 2 isolé à partir des graines de T. foenum-graecum. Byssochlamys spectabilis a montré l’activité cytotoxique la plus importante (1,51 ± 0,2 µg/mL), suivi par Cladosporium cladosporioides 2 (10,5 ± 1,5 µg/mL), puis par Alternaria sp. (13,5 ± 1,8 µg/mL). Seules six souches ont montré une activité contre S. aureus avec des valeurs de MIC qui se situent entre 0,125 et 2 mg/mL dont: Alternaria alternata (0,125 mg/mL), Alternaria sp. (0,250 mg/mL), Byssochlamys spectabilis (0,5 mg/mL). 10 composés purs (0,3 à 40 mg) ont été isolés à partir des extraits bruts d’acétate d’éthyle de Curvularia papendorfii. Le nouveau composé pur (AFB) 3,7,11,15-Tetrahydroxy-18-hydroxymethyl-14,16,20,22,24-pentamethyl-hexacosa-4E,8E,12E,16,18-pentaenoic acid (acide Khartomique) a montré une activité antibactérienne modérée contre S. aureus avec une CIM de 62,5 µg/mL et une faible activité cytotoxique sur les cellules MCF7 avec une IC50 > 100 µM. Le composé pur AF1 a montré une activité cytotoxique modérée sur les cellules HT29 avec une IC50 de 29,78 µM et une très faible activité antibactérienne contre S. aureus. Ces deux composés ne présentent pas d’activité antioxydante
This study investigated, for the first time, the endophytic fungi flora of five Sudanese medicinal plants: Calotropis procera (Ait.), Catharanthus roseus (L.), Euphorbia prostrata (Ait.), Trigonella foenum-graecum (L.) and Vernonia amygdalina (Del.). A total of 23 endophytic fungal strains were isolated from the plants after surface disinfection and different biological tests were performed. Total phenolic content (TPC) and total antioxidant activity of ethyl acetate crude extracts of 21 endophytes and their host plants were estimated using respectively the Folin-Ciocalteu colorimetric method and 1,1,-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging in vitro method. General evaluation of the cytotoxicity of 16 selected endophytes and their host plants was performed by the MTT assay using cancer cells type: Human breast carcinoma (MCF7) and Colon adenocarcinoma (HT29 and HCT116). Preliminary antibacterial screening was done for the 16 endophytes. These extracts were also tested against two representative bacterial strains, Escherichia coli and methicillin-resistant Staphylococcus aureus, by broth dilution tests. The endophyte, Aspergillus terreus 1 from T. foenum-graecum seeds had the highest TPC in term of Gallic Acid Equivalent (89.9 ± 7.1 mg GAE/g) and antioxidant activity (IC50: 18±0.1µg/mL). Byssochlamys spectabilis showed strong cytotoxicity (1.51 ± 0.2 µg/mL) followed by Cladosporium cladosporioides 2 (10.5 ± 1.5 µg/mL), then Alternaria sp. (13.5 ± 1.8 µg/mL). Only six strains showed activity against methicillin-resistant S. aureus with MIC values ranging between 0.125-2 mg/mL, Alternaria alternata (0.125 mg/mL) Alternaria sp. (0.250 mg/mL) and Byssochlamys spectabilis values (0.5 mg/mL). Ten pure compounds (0.3 to 40 mg) were isolated from ethyl acetate crude extract of Curvularia papendorfii .The new pure compound (AFB) 3,7,11,15-Tetrahydroxy-18-hydroxymethyl-14,16,20,22,24-pentamethyl-hexacosa-4E,8E,12E,16,18-pentaenoic acid (Khartoumic acid) revealed moderate antibacterial activity against S. aureus with MIC value 62.5 µg/mL and weak cytotoxicity with a IC50 > 100 µM against MCF7 cells. The pure compound AF1 showed moderate cytotoxic activity with IC50 value of 29.78 µM against HT29 and weak antibacterial activity with MIC 250 µg/mL against S. aureus. Both compounds displayed no antioxidant activity

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Guedes, Alessandra da Silva. "Contribuição ao estudo farmacognóstico das espécies medicinais Averrhoa bilimbi L. e Poiretia bahiana C. Muller." reponame:Repositório Institucional da UFBA, 2009. http://www.repositorio.ufba.br/ri/handle/ri/9868.

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CAPES
O presente trabalho é uma contribuição à pesquisa de plantas medicinais, e descreve o estudo farmacognóstico das espécies Averrhoa bilimbi e Poiretia bahiana no que diz respeito aos aspectos botânicos, fitoquímicos e à avaliação de atividade biológica. As folhas e frutos da espécie A. bilimbi foram caracterizados pelos aspectos morfoanatômicos, e apenas de seus frutos foram realizadas extrações com metanol, seguido de fracionamento para obtenção dos extratos brutos hexânico, clorofórmio e acetato de etlia. Estes extratos foram avaliados quanto ao potencial citotóxico através do bioensaio com o microcrustáceo Artemia salina. Os extratos brutos clorofórmio e acetato de etila foram submetidos ao fracionamento e isolamento de substâncias através de técnicas cromatográficas. A identificação das substâncias isoladas foi realizada através de métodos espectroscópicos, tais como RMN de 1H e 13C. Para a espécie P. bahiana, o estudo envolveu a caracterização anatômica de suas folhas e obtenção de extratos brutos hexânico, clorofórmio, acetato de etlia e hidroalcoólico através de técnicas cromatográficas. Os extratos obtidos foram avaliados quanto ao potencial citotóxico frente a A. salina, e a capacidade seqüestradora de radical livre, medida pelo método DPPH (2,2-difenilpicril- hidrazil). Os resultados apresentados no estudo farmacobotânico das espécies A. bilimbi e P. bahiana permitiram levantar características muito peculiares nos aspectos morfoanatômicos. A espécie A. bilimbi apresentou um elevado potencial citotóxico, evidenciado pela morte de 100% dos microcrustáceos em todos os extratos avaliados. A partir do fracionamento e isolamento das substâncias presentes nos extratos acetato de etila e clorofórmio da espécie A. bilimbi foram isoladas as substâncias 3β-O-β-D-glicopiranosil sitosterol e 3,5-dimetoxi-benzaldeído, até então não descritas para a espécie. Já a espécie P. bahiana apresentou apenas citotoxicidade nos extratos hexânico e clorofórmio, entretanto foi observada atividade antioxidante dos extratos hidroalcoólico, clorofórmio e acetato de etila através do teste com o DPPH, demonstrando ter potencial como fonte de substâncias antioxidantes.
Salvador

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Talag, Agela Hussain Mohammed. "Phytochemical investigation and biological activities of Sanicula europaea and Teucrium davaeanum : isolation and identification of some constituents of Sanicula europaea and Teucrium davaeanum and evaluation of the antioxidant activity of ethanolic extracts of both plants and cytotoxic activity of some isolated compounds." Thesis, University of Bradford, 2016. http://hdl.handle.net/10454/14482.

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The aim of this research was to investigate the phytochemistry of two species Sanicula europaea and Teucrium davaeanum which are traditionally used in treatment of wounds. Four compounds were isolated from the 80% methanolic extract of S. europaea; bis-(2-ethylhexyl) phthalate (1), palmitic acid (2), rosmarinic acid (3), saniculoside N (4). Compounds 1 and 2 were isolated for the first time from this species. The structure elucidation of the isolated compounds was on the basis of 1D, 2D NMR spectroscopy and mass spectrometry measurements. Two compounds were isolated from the crude glycosides extract of T.davaeanum; 6 is a phenylethanoid glycoside and 8 is an iridoid glycoside, from the data available these may be new compounds for which the names davaeanuside A and davaeanuside B are proposed respectively." The total polyphenol content of S. europaea L, T. davaeanum leaves-flowers and T. davaeanum stem were found to be 5.0, 1.20 and 0.65 mg per 100 mg dried plant material respectively. A study of the antioxidant activity of the 50 % ethanol extracts of S. europaea and T. davaeanum showed that on a mg/mg basis S. europaea and T. davaeanum have approximately 5%, 8 % antioxidant capacity of Trolox respectively. A study of the cytotoxic activity of davaeanuside A (6), iridoid glycoside (7), davaeanuside B (8) and saponin compound (10) isolated from the crude glycosides extract of T. davaeanum revealed that saponin compound (10) inhibited the growth of Hela cells by 50 % at 50 μg/ml, P< 0.001, but the other compounds did not show activities against the tested cell lines at 100 μg/ml. The results of this work provide some basis for the traditional use of these species in the treatment of wounds.

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Silva, Filho Eliezer Fernandes da. "Avaliação tóxica, citotóxica e mutagênica de extratos aquosos de Ipomoea asarifolia (Convolvulaceae)." Universidade Federal Rural do Semi-Árido, 2015. http://bdtd.ufersa.edu.br:80/tede/handle/tede/792.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
How do Genus Species Ipomoea station included between as weeds commonly found in cultivated areas, especially Ipomoea asarifolia (salsa) reported as a toxic plant species and causes que neurological disorders. There is little studies on the toxicity quantity make consumer cellular and genetic level these plants nos production animals semi-arid region. It was assessed a toxic capacity, cytotoxic and mutagenic of the aqueous extract of species leaves I. asarifolia (Convolvulaceae) about growth roots in Allium cepa bulbs; and about the frequency of micronucleated erythrocytes in bone marrow cells in vivo rodent (micronucleus test). Also it enrolled a median lethal dose (LD50) and studied the effect of weight in males and females and analyzed the behavior of animals (Hippocratic screening). Aqueous extracts of dried leaves (EFS) and Fresh (EFF) of I. asarifolia not presented toxic effects or cytotoxic in Allium cepa bulbs roots strain. Were observed allelopathic effects nos growth of roots. Aqueous extracts of dried leaves showed sublethal effects 5mg/L concentration and 300 mg/L. And the fresh leaves showed stimulatory effects all as concentrations studied. The aqueous extract of dried leaves and fresh not caused toxic effects and cytotoxic. There is not cytotoxic effect or in mutagenic rodent cells. The LD50 was found 754.26 mg/kg. From: No influence of gender (male and female) on the toxic effect, but at concentrations of 300 mg/kg and 600 mg/kg of weight was lost. The results against knowledge producers qua not like dry leaves not harm the production of animals
As espécies do gênero Ipomoea estão inclusas entre as plantas daninhas comumente encontradas em áreas de cultivo, especialmente Ipomoea asarifolia (salsa) relatada como uma espécie vegetal tóxica e que causa distúrbios neurológicos. Existe pouca quantidade de estudos sobre a toxicidade do consumo a nível celular e genético dessas plantas nos animais de produção da região do Semiárido. Foi avaliada a capacidade tóxica, citotóxica e mutagênica do extrato aquoso de folhas da espécie I. asarifolia (Convolvulaceae) sobre crescimento de raízes em bulbos de Allium cepa; e sobre a frequência de eritrócitos micronucleados em células da medula óssea de roedores in vivo (teste do micronúcleo). Também foi obtida a Dose Letal Mediana (DL50) e foi estudado o efeito do peso em machos e fêmeas e analisado o comportamento dos animais (screening hipocrático). Os extratos aquosos de folhas secas (EFS) e frescas (EFF) de I. asarifolia não apresentaram efeitos tóxicos nem citotóxicos em raízes de bulbos de Allium cepa. Foram observados efeitos alelopáticos nos crescimentos de raízes. Os extratos aquosos de folhas secas apresentaram efeitos subletais nas concentrações de 5mg/L e 300mg/L. E o das folhas frescas apresentaram efeitos estimulatórios em todas as concentrações estudadas. O extrato aquoso de folhas secas e frescas não provocou efeitos tóxicos e citotóxicos. Não houve efeito citotóxico nem mutagênico nas células de roedores. A DL50 encontrada foi 754,26 mg/Kg. Não houve influência do gênero (Macho e fêmea) sobre o efeito tóxico, mas nas concentrações de 300 mg/Kg e 600 mg/Kg houve perda de peso. Os resultados vão de encontro ao conhecimento dos produtores no qual as folhas secas não prejudicam o animal de produção
2017-08-08

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22

Mbeng, Wilfred Otang. "Antifugal evaluation and phytochemical analysis of selected medicinal plants used in the treatment of fungal diseases associated with HIV infection in the Eastern Cape Province, South Africa." Thesis, University of Fort Hare, 2013. http://hdl.handle.net/10353/d1006834.

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Background. As a result of the AIDS pandemic, many people areimmuno compromised andopportunistic fungal infections (OFIs) such as candidiasis are common. Despite the widespread use of medicinal plants in South Africa, there is a dearth of knowledge regarding the use of such plants in the management of these infections. This study evaluates three South African medicinal plants (Arctotis arctotoides, Pittosporum viridiflorum, and Gasteria bicolor) traditionally used in the treatment of OFIs in HIV/AIDS patients, in the Eastern Cape Province, South Africa. Materials and methods. A six-stage process of documentation, evaluation and analysis of results was conducted: (1) Selection of medicinal plants most frequently used in the treatment of OFIs through ethnomedical studies and the survey of specialised literature; (2) Collection and preparation of the extract of each plant; (3) Antifungal evaluation of the crude plant extracts. (4) Phytochemical and antioxidant evaluation of the active crude plant extracts; (5) Cytotoxicity evaluation of the bioactive extracts using the Chang liver cell line, and (6) Statistical analysis of the results. Ethnobotanical information was obtained through interviews with traditional healers and AIDS patients with the aid of semi-structured questionnaires, direct observations and by reviewing studies reported in the literature. Following the approval from the University of Fort Hare‘s Ethics Committee, 101 HIV/AIDS patients were recruited through convenience sampling into an anonymous cross-sectional questionnaire study. The agar diffusion and micro-dilution methods were used to determine the antifungal activities of the hexane, acetone and aqueous extracts of A. arctotoides, G. bicolor and P. viridiflorum against 10 opportunistic fungi.

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23

Peixoto, Iza Teixeira Alves. "Atividade antimicrobiana do óleo essencial de diferentes acessos de Mentha spp. contra Candida albicans e Candida dubliniensis." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289367.

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Orientadores: José Francisco Hofling, Marta Cristina Teixeira Duarte
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia
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Resumo: O objetivo desse estudo foi avaliar a ação antimicrobiana de óleos essenciais e frações de diferentes acessos de Mentha spp. contra Candida spp., identificando seus compostos e verificando sua citotoxicidade. Os 64 óleos essenciais de diferentes acessos de Mentha spp. foram extraidos utilizando as partes aéreas da planta fresca, por hidrodestilaçãoo em sistema tipo Clevenger. Os óleos foram testados contra isolados clínicos e de referência de Candida albicans (CBS 562) e Candida dubliniensis (CBS 7987). A CIM foi determinada por meio do método de microdiluição (CLSI, 2002). Os melhores acessos testados em células planctônicas foram fracionados em 5 partes em cromatografia de coluna seca e testados posteriormente contra biofilme de C. albicans (SC 5314). Com o inoculo padronizado em meio RPMI-1640, os biofilmes foram produzidos em placas esterilizadas de polietileno de 96 pocos, para testes dos óleos e frações em biofilme maduro e biofilme em formação, sendo quantificados com solução de XTT e analisados através de microscopia óptica e confocal a laser. Os compostos dos melhores óleos e frações foram identificados por cromatografia em camada delgada e cromatografia a gas com detector de massas. A citotoxicidade também foi provada em painel de diferentes linhagens celulares células epiteliais, por meio da avaliação da atividade antiproliferativa, in vitro, utilizando-se o ensaio de sulforrodamina B para avaliação do crescimento celular. O melhor rendimento em óleo essencial (base seca) foi observado para o acesso de M. rotundifolia CM 31 (1,5 %). Quatro óleos se destacaram, apresentando forte atividade com amplo espectro, sendo M. canadensis (CM 05) - (<0,007 a 0,500 mg/mL); M. spicata (CM 30) (0,062 mg/mL a 0,500 mg/mL); M. arvensis CM 36 (<0,007 mg/mL a 1 mg/mL) e M. suaveolens x spicata (CM 52) - (0,062 mg/mL a 0,500 mg/mL). As frações F2 e F3 de M. suaveolens x spicata CM 52 demonstraram a melhor atividade dentre os óleos e frações testadas, apresentando 49 % e 38 % de inibição na concentração de 0,5 mg/mL para biofilme maduro e 70 % de inibição (a 0,062 mg/mL) e 61 % de inibição (a 0,125 mg/mL), respectivamente, para inibição de biofilme em formação. Esses resultados foram confirmados pelas analises microscópicas. Os compostos majoritários do óleo de M. canadensis CM 05 foram carvona (74,84 %) e linalol (4,84 %);de M. spicata CM 30 oxido de piperitenona (28,05 %), beta-E-farneseno (18,58 %) e gama-muuroleno (17,38 %); M. arvensis CM 36 Linalol (33,24 %), acetato de linalol (21,97 %) e alfaterpineol (11,77 %); de M. suaveolens x spicata CM 52 pulegona (52,20 %), piperitenona (29,51 %) e gama-muuroleno (4,44 %). Os óleos essenciais de Mentha spp. apresentam atividade antimicrobiana contra células planctônicas de Candida spp. (de moderada a fraca), exceto os óleos originados dos acessos de M. canadensis CM 05, M. spicata CM 30, M. arvensis CM 36 e M. suaveolens x spicata CM 52. As fracoes F2 e F3 de Mentha suaveolens x spicata CM 52 demonstram efeito antimicrobiano inibitório sobre biofilme em formação e sobre biofilme maduro, alem de ausência de citotoxicidade para células testadas
Abstract: The aim of this study was to evaluate the antimicrobial activity of essential oils and fractions of different accessions of Mentha spp. against Candida spp., identifying compounds and verifying its cytotoxicity.The essential oils of 64 different accessions of Mentha spp. were extracted using the fresh aerial parts of the plant by hydrodistillation cleavenger type system Then, The the oils were tested against clinical isolates and reference strains Candida albicans (CBS 562) and Candida dubliniensis (CBS 7987). The minimal inhibitory concentration (MIC) was determined by microdilution method, using the CLSI protocol. The best accessions tested on planktonic cells were separated into 5 parts by dry column, and oils and fractions were subsequently tested against biofilms of C. albicans (SC 5314). With standardized inoculum in RPMI-1640, the biofilms were produced in sterile polyethylene plates with 96 wells, for to evaluate the oils and fractions in preformed biofilm and inhibition biofilm formation. After the biofilm was quantified with XTT solution and analyzed by optical and confocal microscopy. The compounds were further identified by thin layer chromatography (TLC) and gas chromatography mass spectrometry (GC-MS). The cytotoxicity was also tested in epithelial cells as well as antitumor activity, by evaluating the antiproliferative activity in different cell lines using the test sulforrodamina B (SBR) for evaluation of cell growth.The best yield in essential oil (dry basis) was observed for the accessions M. rotundifolia CM 31 (1.5% dry basis). Among the 64 oils, four stood out, showed strong activity with broad spectrum, inhibiting all strains tested, and these, M. canadensis (CM 05) - (<0.007 to 0.187 mg/mLto 0.500 mg/ml), M. spicata (CM 30) - (0.062 mg/mL to 0.500 mg/ml), M. arvensis CM 36 (<0.007 mg/mL to 1 mg/mL) and M. spicata x suaveolens (CM 52) - (0.062 mg/mL to 0.500 mg/mL). Fractions F2, F3 M. spicata x suaveolens CM 52 showed the best activity among the tested oils and fractions, showing 49% and 38% inhibition at 0.5 mg/mL for preformed biofilm and 70% inhibition (at 0.062 mg/mL) and 61% inhibition (at 0.125 mg/mL), respectively, for inhibitory biofilm formation. These results were confirmed by microscopic analysis. The mainly oil M. canadensis 05 CM were carvone (74.84%), linalool (4.84 %); M. spicata CM piperitenone oxide were 30 (28.05%), beta-E-farnesene (18.58%) and gamma-muuroleno (17.38%); M. arvensis CM 36 were Linalool (33.24%), acetate, linalool (21.97%) and alphaterpineol (11.77%); M. spicata x suaveolens CM 52 were pulegone (52.20 %), piperitenone (29.51 %) and gamma-muurolene (4.44 %). Fractions F2 and F3 showed antiproliferative activity for most strains, showing lack of cytotoxicity in epithelial cells tested.The essential oils of Mentha spp. exhibit antimicrobial activity against planktonic cells of Candida spp. (moderate to weak), except oils originating from accessions of M. canadensis CM 05, M. spicata CM 30, M. arvensis CM 36 and M. suaveolens x spicata CM 52. The fractions F2 and F3 of Mentha spicata x suaveolens CM 52 shows antimicrobial effect on preformed biofilm and inhibition biofilm, and absence of cytotoxicity to mammalian cells
Doutorado
Microbiologia e Imunologia
Doutor em Biologia Buco-Dental

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24

Silva, Viviane Araújo da. "Avaliação citotóxica e genotóxica de Mimosa tenuiflora (Willd.) Poir. (Mimosaceae)." Universidade Federal da Paraíba, 2012. http://tede.biblioteca.ufpb.br:8080/handle/tede/6722.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Mimosa tenuiflora (Willd.) Poir., popularly known as Jurema preta, is a plant family Mimosaceae, found mainly in the states of Piauí, Ceará, Rio Grande do Norte, Paraiba, Pernambuco, Alagoas, Sergipe and Bahia, which this species is typical of semi-arid areas of Brazil. In folk medicine, the bark of the stem is the main part of the plant used to treat various ailments such as burns and inflammations. This study aimed to investigate the cytotoxicity and genotoxicity of crude ethanolic extract (BSE) and Mimosa tenuiflora in prokaryotic and eukaryotic cells in order to encourage later, safely, its use as a source of potentially therapeutic drugs or act as pharmacological tools. To this end, we evaluated the antimicrobial activity against Gram negative and Gram positive clinical importance, investigated the potential cytotoxic utilizing the hemolytic activity and osmotic fragility (anti-hemolytic), as well as potential antioxidant and anti-oxidant in human erythrocytes, there was observed the potential mutagenic and anti-mutagenic in bacterial cells through the Ames test and also evaluated the clastogenic and aneugenic potential using the micronucleus test in peripheral blood of mice in vivo. The results showed that the EEB and the tannins of M.tenuiflora had antibacterial activity against all strains of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli tested and this was characterized as strong with MIC ranging from 62,5 to 250 μg.mL-1. In the investigation of cytotoxic of M.tenuiflora it was observed that the extract did not induce a significant degree of hemolysis and even protected the erythrocyte membrane against hemolysis. In tests of the oxidizing activity of M.tenuiflora, this plant did not cause oxidation of hemoglobin and tests of the extract antioxidant activity behaved as a powerful antioxidant. In the investigation of genotoxicity, we observed that M.tenuiflora was not mutagenic, or in vitro tests and in vivo. Thus, the extract of M.tenuiflora has no cytotoxic or genotoxic that compromise its use as a source of potentially therapeutic drugs.
Mimosa tenuiflora (Willd.) Poir., popularmente conhecida como jurema preta, é uma planta da familia Mimosaceae, encontrada principalmente nos estados do Piauí, Ceará, Rio Grande do Norte, Paraíba, Pernambuco, Alagoas, Sergipe e Bahia, sendo esta espécie típica das áreas semi-áridas do Brasil. Na medicina popular, a casca do caule é a principal parte da planta utilizada no tratamento de diversas enfermidades como infecções. O presente trabalho teve como objetivo investigar a citotoxicidade e a genotoxicidade do extrato etanólico bruto (EEB) da Mimosa tenuiflora em células procarióticas e eucarióticas com a finalidade posterior de incentivar, com segurança, a sua utilização como fonte de drogas potencialmente terapêuticas ou que atuem como ferramentas farmacológicas. Para tanto, avaliou-se a atividade antimicrobiana frente a bactérias Gram negativas e Gram positivas de importância clínica, investigou-se o potencial citotóxico utilizando como parâmetro a atividade hemolítica e a fragilidade osmótica (anti-hemolítica), assim como o potencial oxidante e antioxidante em eritrócitos humanos, observou-se o potencial mutagênico e antimutagênico em células bacterianas através do teste de Ames e também avaliou-se o potencial clastogênico e aneugênico através do teste do micronúcleo em sangue periférico de camundongos in vivo. Os resultados mostraram que o EEB e os taninos de M.tenuiflora tiveram atividade antibacteriana contra toda as linhagens de Staphylococcus aureus, Pseudomonas aeruginosa e Escherichia coli testadas, e esta foi caracterizada como forte com CIM variando de 62,5 a 250 μg.mL-1. Na investigação citotóxica do EEB de M.tenuiflora observamos que o extrato não induziu um grau significativo de hemólise e ainda protegeu a membrana do eritrócito contra hemólise. Nos testes de atividade oxidante o EEB de M.tenuiflora não provocou oxidação da hemoglobina e nos testes de atividade antioxidante o extrato se comportou como um poderoso agente antioxidante. Já na investigação genotóxica, observamos que o EEB da M.tenuiflora não foi mutagênico, nem nos testes in vitro nem in vivo e apresentou efeito antimutagênico em algumas linhagens ensaiadas. Sendo assim, a baixa atividade citotoxicidade e genotoxicidade de M.tenuiflora não comprometem seu uso como fonte de droga potencialmente terapêutica.

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25

Carvalho, José Carlos Borges de. "Estudo químico e biológico das espécies vegetais caboverdianas Echium hypertropicum Webb e Echium stenosiphon Webb subsp. Stenosiphon." Niterói, 2017. https://app.uff.br/riuff/handle/1/3281.

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Echium hypertropicum Webb e Echium stenosiphon Webb subsp. stenosiphon são arbustos endêmicos de Cabo Verde, usados na medicina popular para o tratamento de distúrbios gastrintestinais e tosse. As duas espécies tiveram suas frações alcalóidicas obtidas por extração ácido-base. A análise por CG-EM e ESI-EM/EM indicou a presença de alcaloides pirrolizidínicos (APs) e as substâncias purificadas foram analizadas por experimentos de RMN de 1D e 2D. Um total de 10 alcaloides foram isoladas e identificadas, sendo que 8 identificadas através da comparação de suas massas moleculares e padrões de fragmentação de massas, com a base de dados NIST e os dados da litratura para o género. Os diésteres hepatotóxicos equimidana e 7-(2-metilbutiril)-9-equimidinilretronecina foram identificadas em ambas as espécies. Os alcaloides 7-senecioilretronecina, 9-angeloilretronecina, licopsamina, 7-acetil-licopsamina e equihumilina foram identificados nas folhas de E. hypertropicum, enquanto que o N-óxido da 7-(2-metilbutiril)-9-equimidinilretronecina foi identificado nas folhas de E. stenosipnhon. A equimidina foi o componente majoritário na fração em éter dietílico das folhas de E. hypertropicum, enquanto a 7-(2-metilbutiril)-9-equimidinilretronecina foi o componente majoritário na fração em diclorometano das folhas de E. stenosiphon. O alcaloide 7-(2-metilbutiril)-9-equimidinilretronecina N-óxido foi identificado pela primeira vez no gênero Echium. Em adição, 22 componentes de óleo essencial foram identificadas nas flores de Echium hypertropicum, sendo trans-fitol (30,64 %), n-pentacosano (8,28 %) e n-tricosano (6,73) como componentes majoritários. O triterpeno friedelina foi também isolado das folhas de E. hypertropicum. Na avaliação da atividade antibacteriana, os extratos etanólicos das duas espécies vegetais e o alcaloide 7-(2-metilbutiril)-9-equimidinilretronecina foram capazes de inibir o crescimento de Staphylococcus aureus ATCC 29213 com CMI de 250,0 μg/mL e 25,0 μg/mL, respectivamente. A atividade anticolinesterásica foi avaliada e a equimidina foi capaz de inibir a enzima acetilcolinesterase nas concentrações testadas com o valor de P = 0,0011. O alcaloide 7-(2-metilbutiril)-9-equimidinilretronecina retardou o crescimento do fitófago Dysdercus peruvianus na concentração de 1mg/mL. Os extratos etanólicos de E. hypertropicum e E. stenosiphon (3,9 μg/mL) foram avaliados frente ao vírus HSV. O extrato etanólico de E. hypertropicum apresentou uma porcentagem de inibição (PI) de 27,5% contra HSV-1S e 43,8% contra HSV-2S. Apresentaram ainda elevada citotoxidade para as celulas Vero, utilizadas como sistema hospedeiro (CC50 de 140,10 μg/mL e 96,86 μg/mL). A composição química e as atividades biológicas de E. hypertropicum e E. stenosiphon subsp. stenosiphon foram relatadas pela primeira vez. As substâncias identificadas podem ser utilizadas no futuro como marcadores quimiotaxonômicos para o gênero Echium
Echium hypertropicum Webb and Echium stenosiphon Webb subsp. stenosiphon are endemic capeverdian shrubs used in folk medicine for the treatment of gastrointestinal diseases and cough, respectively. The two species had their alkaloidal fractions obtained by acid-base extraction. GC-MS and ESI-MS/MS analysis indicated the presence of pyrrolizidine alkaloids (PAs) and purified substances were also analyzed by 1D and 2D NMR experiments. A total of 10 alkaloids were isolated and identified, which 8 were identified by comparing their molecular masses and mass fragmentation patterns with NIST database and literature data for the genus. The hepatotoxic diesters echimidine and 7-(2-methylbutyryl)-9-echimidinylretronecine were identified in both species. The alkaloids 7-senecioylretronecine, 9-angeloylretronecine, lycopsamine, 7-acetil-lycopsamine and echihumiline were identified in the leaves of E. hypertropicum, whereas the 7-(2-methylbutyryl)-9-equimidinylretronecine N-oxide was identified in the leaves of E. Stenosipnhon. Echimidine was the major component in the diethyl ether fraction from leaves of E. hypertropicum, whereas the 7-(2-methylbutyryl)-9-echimidinylretronecine was the major component in dichloromethane fraction from leaves of E. stenosiphon. The alkaloid 7-(2-methylbutyryl)-9-echimidinylretronecine N-oxide was identified for the first time in Echium genus. In addition, 22 essential oil components were identified in E. hypertropicum flowers, with trans-phytol (30.64%), n-pentacosane (8.28%) and n-tricosane (6.73%) as the major components. The triterpene friedelin was also isolated from E. hypertropicum leaves. The antimicrobial susceptibility tested with the ethanolic extract and the alkaloid 7-(2-methylbutyryl)-9-equimidinilretronecine against Staphylococcus aureus ATCC 29213 showed a MIC of 250.0 μg/mL and 25.0 μg/mL, respectively. The anticholinesterasic activity was evaluated and echimidine was able to inhibit the enzyme at the concentrations tested with p value = 0.0011. The alkaloid 7-(2-methylbutyryl)-9-equimidinilretronecine retarded the growth of phytophagous Dysdercus peruvianus at the concentration of 1mg/mL. For the antiviral activity, the ethanolic extracts from E. hypertropicum and E. stenosiphon (3.9 μg/mL) were analyzed against HSV. The ethanolic extract of E. hypertropicum showed an inhibition percentage (IP) of 27.5% against HSV-1S and 43.8% against HSV-2S. Also showed high cytotoxicity for the Vero cells, used as host for the herpesvirus (CC50 140.10 μg/mL and 96.86 μg/mL). The chemical composition and biological activities of the leaves and flowers of E. hypertropicum and E. stenosiphon subsp. stenosiphon are reported for the first time. The identified pyrrolizidine alkaloids could be used in future as chemotaxonomic markers for Echium genus

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26

Oliveira, Aline Mylena Guedes da Costa. "Avalia??o da atividade antimal?rica e citot?xica de plantas medicinais dos Biomas Caatinga e Amaz?nico." Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13074.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Resistance of Plasmodium falciparum to the usual antimalarials, as well as their adverse effects and high cost, has led to the search of new drugs against malaria. Several of these have been developed from medicinal plants based on ethnopharmacology, including the most widely used antimalarials today: quinine and artemisinin. In the present study schizonticide activity of extracts and fractions of a number of medicinal plants from the Caatinga and Amazon biomes were assessed based on ethnopharmacological and chemosystematic information. These included Ximenia americana, Maytenus rigida, Sideroxylon obtusifolium, Stryphnodendro coriaceum, Bowdichia virgiliodes, Schinopis brasiliensis and Picrolemma sprucei, the last, an Amazon species. Antimalarial tests of blood schizonticides were conducted in Swiss mice infected with P. berghei and in vitro against P. falciparum. In vitro cytotoxicity studies were carried out using HeLa, CHO, 3T3, Raw and HEPG2 cell lines. Except for X. americana, all species exhibited in vivo or in vitro antimalarial activity, inhibiting parasitic growth by up to 79%. Extracts exhibited moderate toxicity with dosedependent kinetics. In this sense, ethnopharmacological and chemosystematic approaches were shown to be useful and promising tools in the search of new drugs. These findings represent a significant contribution to scientific knowledge of the antimalarial potential of Brazilian flora, thereby opening perspectives for the development of new antimalarials
A resist?ncia do Plasmodium falciparum aos antimal?ricos usuais, bem como os seus efeitos adversos e custo elevado, tornam necess?ria a busca de novos medicamentos contra a mal?ria. Diversos f?rmacos foram descobertos a partir de plantas medicinais com base na etnofarmacologia, inclusive os antimal?ricos mais usados atualmente; quinina e artemisinina. Neste trabalho foi avaliada a atividade esquizonticida de extratos e fra??es de algumas plantas medicinais dos Biomas da Caatinga e Amaz?nico a partir de um referencial etnofarmacol?gico e de quimiossistem?tica. S?o elas: Ximenia americana, Maytenus rigida, Sideroxylon obtusifolium, Stryphnodendro coriaceum, Bowdichia virgiliodes, Schinopis brasiliensis e Picrolemma sprucei, sendo esta ?ltima, uma esp?cie amaz?nica. Os testes antimal?ricos de esquizonticidas sangu?neos foram feitos em camundongos Swiss infectados com P. berghei e in vitro contra o P. falciparum. Estudos de citotoxicidade in vitro foram realizados utilizando as linhagens celulares HeLa, CHO, 3T3, Raw e HEPG2. A excess?o da X. americana, todas as esp?cies apresentaram atividade antimal?rica in vivo ou in vitro, inibindo o crescimento do parasito em at? 79%. Os extratos exibiram toxicidade moderada com cin?tica de atividade dose-dependente. Nesse contexto, a abordagem etnofarmacol?gica associada ao perfil quimiossistem?tico, se mostram ferramentas ?teis e promissoras na busca de novos f?rmacos, permitindo contribuir significativamente para o conhecimento cient?fico do potencial antimal?rico da flora brasileira e deste modo, abrir perspectivas para o desenvolvimento de novos antimal?ricos

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Carvalho, Gabriel Costa de. "Análise do perfil fenotípico e funcional das células natural Killer e linfócitos TCD8+ no Líquen plano." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/5/5133/tde-09082016-164859/.

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INTRODUÇÃO: Líquen plano (LP) é uma doença mucocutânea de natureza inflamatória crônica de etiologia ainda desconhecida. Alterações na resposta imune inata, como aos padrões moleculares associados à patógenos (PAMPs) e padrões moleculares associados ao dano (DAMPs) podem levar à inflamação crônica e contribuir com a patogênese do LP. OBJETIVO: Avaliar o efeito da ativação via o DAMP S100A8 e o receptor Toll-like 4 (TLR-4) em células Natural killer (NK) e TCD8 citotóxicas e suas subpopulações de memória/efetoras em pacientes com LP. MÉTODOS: Foram selecionados 25 pacientes com LP (22 mulheres, 3 homens) com idade média de 43,46 anos ± 8,46 e um grupo controle com 25 indivíduos (22 mulheres, 3 homens) com idade média de 42 anos ± 5,5. A determinação transcricional e da expressão por imunohistoquimica dos DAMPs S100A8, HMGB-1 e de TLR-4 e RAGE foi realizada em biópsias de lesões cutâneas de indivíduos com LP, e os níveis séricos de S100A8, HMGB-1, MICA e MICB foram determinados por ELISA. As células mononucleares (CMNs) de sangue periférico foram avaliadas por citometria de fluxo quanto a frequência de TNF, IL-1beta e o marcador de desgranulação CD107a em células TCD8+ e células NK CD56+ e suas subpopulações. A avaliação da via de sinalização de TLR em células TCD8+ purificadas e ativadas com S100A8 foi analisada por PCR array e a determinação da expressão de mRNA dos componentes do inflamassoma em células TCD8+ ativadas com S100A8 por PCR em tempo real. RESULTADOS: Foi evidenciado nos indivíduos com LP elevada expressão da proteína S100A8 nas lesões cutâneas e de HMGB-1, TLR-4 e RAGE na derme, em paralelo ao aumento da expressão de mRNAs para S100A8 e S100A9 e diminuição de RAGE. Além disto, uma elevação dos níveis séricos do dímero S100A8/A9 foi detectada nos pacientes comparados aos controles, ao contrário do DAMP HMGB-1 que mostrou níveis similares em ambos os grupos. A influência do S100A8 em células TCD8+ e células NK, foi analisada em CMNs pela ativação com o lipopolissacáride e a proteína recombinante S100A8, ambos ligantes de TLR-4. Nos indivíduos com LP foi detectado aumento da resposta citotóxica de linfócitos TCD8+ e células NK CD56bright pela expressão do marcador de desgranulação CD107a por citometria de fluxo. A proteína S100A8 foi capaz de induzir a expressão de genes pró-inflamatórios como IL-1beta, TNF e IL-6 em células TCD8+ de pacientes com LP em contraste com os indivíduos saudáveis que mostraram expressão IL-10 e IFN tipo I. As células TCD8+ de indivíduos com LP ativadas ou não com S100A8 expressam transcritos de NLRP1, NLRP3 e AIM-2 e produzem IL-1beta em níveis similares a controles saudáveis. Além disso, células TCD8+ ativadas com S100A8 mostraram aumento de expressão TLR3, TLR5, TLR7 e TLR8 na doença comparada às biopsias de controles. O aumento da resposta TCD8+ citotóxica foi principalmente mediado pelo subtipo de memória efetora (TEM, CCR7- CD45RA-). Elevação basal da expressão do receptor ativador NKG2D e inibidor NKG2A foi observado em células NK CD56dim nos indivíduos com LP e um nível similar do ligante solúvel MICB em ambos os grupos. CONCLUSÃO: Estes resultados evidenciam que componentes da imunidade inata, como a proteína S100A8 pode contribuir na manutenção do perfil inflamatório do LP
BACKGROUND: Lichen planus (LP) is a mucocutaneous inflammatory chronic disease of unknown etiology. Alterations in the innate immune response such as the pathogen-associated molecular pattern (PAMPs) and damage-associated molecular pattern (DAMPs) can lead to chronic inflammation and contribute to the pathogenesis of LP. OBJECTIVE: Evaluate the effect of the activation trough the DAMP S100A8 and the Toll-like receptor 4 (TLR-4) on the Natural killer cells (NK) and cytotoxic TCD8 cells and their memory / effector subsets in LP disease. METHODS: We selected 25 patients with LP (22 women, 3 men) with a mean age of 43.46 years ± 8.46 and a control group of 25 subjects (22 women, 3 men) with a mean age of 42 ± 5, 5. The transcriptional determination and protein expression by immunohistochemistry of DAMPs, S100A8 and HMGB-1 as well as TLR-4 and RAGE was performed on biopsies of skin lesions from patients with LP, and serum levels of S100A8, HMGB-1, MICA and MICB were determined by ELISA. Peripheral blood mononuclear cells (PBMCs) were assessed by flow cytometry to evaluate the frequency of TNF, IL-1beta and the degranulation marker CD107a in CD8+ T cells and CD56 + NK cells and their subsets. The evaluation of the TLR signaling pathway in purified CD8 + T cells activated with S100A8 were analyzed by PCR array and the determination of mRNA expression of inflammasome components on CD8 + T cells activated by S100A8 was measured by real time PCR. RESULTS: It was shown in the LP individuals an increased expression of the S100A8 protein in the cutaneous lesions and HMGB-1, TLR-4 and RAGE in the dermis, in parallel to increased level of mRNAs for S100A8 and S100A9 and decreased expression of RAGE. Moerover, increased serum levels of the dimer S100A8 / A9 was detected in patients compared to controls, in contrast to DAMP HMGB1 that revealed similar levels in both groups. The influence of S100A8 in CD8 + T cells and NK cells, was analyzed in PBMC activating with lipopolysaccharide and recombinant protein S100A8, both ligands of TLR-4. It was detected in LP individuals, an increased cytotoxic response of CD8+ T lymphocytes and CD56bright NK cells trough CD107a degranulation marker expression. The S100A8 protein was able to induce the pro-inflammatory genes expressions such as IL-1beta, TNF and IL-6 in CD8 + T cells of LP patients in contrast to healthy subjects who promoted IL-10 expression and type I IFN. CD8 + T cells of LP individuals activated or not with S100A8 are able to express NLRP1, NLRP3 and AIM-2 and IL-1beta production at similar levels to healthy controls. Moreover, CD8 + T cells activated with S100A8 showed increased expression of TLR3, TLR5, TLR7 and TLR8 in LP compared to biopsies from healthy controls. The increased CD8 + T cells cytotoxic response was mediated by the subtype of effector memory (TEM CD45RA- CCR7). The increased baseline expression of activating receptor NKG2D and the inhibitory NKG2A in the NK CD56dim cells in LP individulas, and the similar level of MICB soluble in both groups. CONCLUSION: These results shows that innate immunity components, such as S100A8 protein may contribute to the maintenance of LP inflammatory profile

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Rezk, Ahmed Verfasser], Matthias [Akademischer Betreuer] Ullrich, Klaudia [Akademischer Betreuer] [Brix, Nikolai [Akademischer Betreuer] Kuhnert, and Dirk [Akademischer Betreuer] Albach. "From Ethnomedicine to Application: Biological Activities and Cytotoxicity of Leaf Extracts from Plants of the Genus Rhododendron / Ahmed Rezk. Betreuer: Matthias Ullrich ; Klaudia Brix. Gutachter: Matthias Ullrich ; Klaudia Brix ; Nikolai Kuhnert ; Dirk Albach." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2015. http://d-nb.info/1087325749/34.

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Lima, Maíra Conceição Jeronimo de Souza. "Estudo sobre a toxicidade da Aspidosperma pyrifolium (pereiro)." Universidade Federal Rural do Semi-Árido, 2011. http://bdtd.ufersa.edu.br:80/tede/handle/tede/411.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
This study aimed to evaluate the spontaneous cases of poisoning in goats, rats and toxicity in vitro cytotoxicity of Aspidospema pyrifolium. In all spontaneous cases studied, the plant is ingested and the abortion cases occurred exclusively in goats. Most cases of abortion occurred during the dry season and early rainy season, and experienced the goats were less affected than the young goats. We used male and female rats of Wistar strain. The extract of the plant A. pyrifolium was administered in females at day 15 of gestation or from the 15th to the 17th day of gestation, which showed reduced fetal weight and strong evidence of maternal toxicity. Rats subjected to intraperitoneal injection of the extract of A. pyrifolium showed motor dysfunction and death, male rats were more resistant than females. The administration of atropine, diazepam and xylazine did not help in preventing the effects of toxicity. The evaluation of osmotic fragility of red blood cells was performed with the plant extract in different concentrations. In addition, we used larvae from a day of brine shrimp, which were incubated with different concentrations of the extract. It was found that the extract of A. pyrifolium promoted hemolysis and was lethal to A. saline. These in vitro tests may be useful as adjunct tests for further studies with this plant.
O presente trabalho teve por objetivo avaliar casos espontâneos de intoxicação em caprinos, toxicidade em ratos e citotoxicidade in vitro da Aspidospema pyrifolium. Em todos os casos espontâneos estudados, a ingestão da planta e os casos de aborto ocorreram exclusivamente em caprinos. A maioria dos casos de aborto ocorreu durante a estação seca e início da estação chuvosa, e as cabras experientes eram menos afetadas do que as cabras jovens. Foram utilizados ratos machos e fêmeas da linhagem Wistar. O extrato obtido da planta A. pyrifolium foi administrado nas fêmeas no 15º dia de gestação ou a partir do 15º ao 17º dia de gestação, que apresentaram redução do peso fetal e fortes indícios de toxicidade materna. Ratas submetidas a injeção intraperitoneal do extrato da A. pyrifolium apresentaram distúrbios motores e morte; ratos machos foram mais resistentes do que as fêmeas. A administração de atropina, xilazina e diazepam não auxiliou na prevenção dos efeitos de toxicidade. A avaliação da fragilidade osmótica das células vermelhas do sangue foi realizada com o extrato da planta em diferentes concentrações. Além disso, utilizou-se larva de um dia de Artemia salina, que foram incubadas com diferentes concentrações do extrato. Verificou-se que o extrato de A. pyrifolium promoveu hemólise e foi letal para A. salina. Estes testes in vitro podem ser úteis como testes adjuntos de mais estudos com esta planta.

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Gonçalves, Carolina Lambrecht. "Bacteriostasia, citotoxicidade, atividade antioxidante e sinergismo com antibacterianos comerciais de plantas bioativas com inidicativo medicinal." Universidade Federal de Pelotas, 2014. http://repositorio.ufpel.edu.br:8080/handle/prefix/3029.

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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
O objetivo deste estudo foi avaliar a atividade antimicrobiana, antioxidante, os efeitos citotóxicos, fitoquímica e a interação de dez plantas com seis antibióticos. A atividade antimicrobiana dos extratos hidroalcoólicos foi analisada pelo método de macrodiluição frente a isolados de Staphylococcus spp e E.coli. Quanto a fitoquímica, avaliou-se a presença de compostos fenólicos, taninos e carotenóides. A atividade antioxidante foi detectada pela capacidade de neutralização do DPPH e os efeitos citotóxicos por meio do teste de Vermelho neutro. As análises fitoquímicas indicaram diferentes valores de compostos fenólicos, de taninos e escassas concentrações de carotenóides nas amostras. Os resultados demonstraram uma maior sensibilidade das bactérias Gram positivas frente aos extratos, sendo S. cumini o mais efetivo com CIM de 0,08 à 0,74mg/mL para Staphylococcus spp e o extrato de S.terebinthifolius o mais eficiente frente a E.coli, com CIM de 0,8 à 3,3 mg/mL. Staphylococcus apresentou uma maior susceptibilidade às interações entre antimicrobianos, havendo efeitos sinérgicos frente a cinco dos seis antibióticos utilizados nas associações com T.minuta e R.officinalis, enquanto que E.coli apresentou os melhores resultados com o extrato de S.terebinthifolius. Os extratos apresentaram-se como antioxidantes, destacando-se a folha de S.terebinthifolius e de E.uniflora, inibindo o DPPH na concentração de 0,17 mg/mL. Na citotoxicidade, P.cattleianum foi a espécie menos nociva, com uma viabilidade celular de 100% na concentração de 2,84 mg/mL. Estes resultados possibilitam a caracterização das espécies vegetais quanto as suas propriedades biológicas e seus efeitos citotóxicos, sendo de relevância na elaboração de novos fitoterápicos e quanto ao seu uso pela população.
The aim of this study was to evaluate the antimicrobial, antioxidant, cytotoxic effects, phytochemical and interaction of ten plants with six antibiotics. The antimicrobial activity of hydroalcoholic extracts were analyzed by method macrodilution against Staphylococcus spp and E.coli. As phytochemical the presence of phenolic compounds, tannins and carotenoids is evaluated. The antioxidant activity was detected by neutralizing capacity of DPPH and cytotoxic effects through the Neutral Red test. The phytochemical analysis indicated different amounts of phenolic compounds, tannins and sparse concentrations of carotenoids in samples. The results showed a higher sensitivity of Gram-positive bacteria against to the extracts the S. cumini the most effective with MIC of 0.08 to 0.74 mg/mL for Staphylococcus spp and extract S.terebinthifolius more efficient for E. coli with an MIC of 0.8 to 3.3 mg/mL. Staphylococcus showed an increased susceptibility to interactions between drugs, with synergistic effects against five of the six antibiotics used in association with T.minuta and R.officinalis, while E. coli showed the best results with the extract S.terebinthifolius. The extracts were presented as antioxidants, highlghting the sheet S.terebinthifolius and E.uniflora, inhibiting DPPH at a concentration of 0.17 mg/mL. In the cytotoxicity P.cattleianum was less harmful species, with 100% cell viability at the concentration of 2.84 mg/ml. These results enable the characterization of plant species and their biological properties and their cytotoxic effects, being of relevance in the development of new herbal medicines and for its use by the population.

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Carvalho, Nayane Chagas. "Análise da citotoxicidade e genocitoxicidade da Aloe vera associada a medicamento endodôntico e fotobiomodulação a laser." Universidade Federal de Sergipe, 2016. https://ri.ufs.br/handle/riufs/5909.

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This study aims to evaluate the effect of a drug in order to avoid the appearance of side effects of human pulp fibroblasts. The groups were divided into: CTR with culture medium with fibroblasts; CL, FTL only; AA, Aloe vera with distilled water; AL, Aloe vera with distilled water and FTL; HA, calcium hydroxide P.A. With distilled water; HL, calcium hydroxide P.A. With distilled water and FTL; HAA, calcium hydroxide P.A. With Aloe vera and distilled water; HAL, calcium hydroxide P.A. With Aloe vera, distilled water and FTL. Cytotoxicity evaluation was performed with the MTT reagent at 24, 48 and 72 h, for the evaluation of genotoxicity the micronucleus test was used in 24 h. At 24 h, the CL group presented a greater media of cellular viability, and the HA showed lower mean but stimulated greater number of cell division. At 48 h, the CL group presented a higher medium of cellular viability of high genotoxicity, and the HAL showed lower mean. The AL group showed a higher percentage of surviving cells in 72 h with statistic different from the HA and HL groups (p <0.05). (P <0.001) and to the AA group (p <0.01). The AL group exhibited high genotoxicity with significant results when the CTR group (p <0.001) and the AA group (p <0.01). It is concluded that Aloe vera allowed a greater cell viability in human pulp fibroblasts in the presence of calcium hydroxide, with the increase of the genotoxicity increase in this association. Calcium hydroxide and an FTL showed higher cytotoxicity.
Este estudo objetiva avaliar in vitro o efeito da Aloe vera associada a medicamento de uso endodôntico combinados ou não a FTL em fibroblastos pulpares humanos FP6. Os grupos foram divididos em: CTR com meio de cultura com fibroblastos; CL, apenas FTL; AA, Aloe vera com água destilada; AL, Aloe vera com água destilada e FTL; HA, hidróxido de cálcio P.A. com água destilada; HL, hidróxido de cálcio P.A. com água destilada e FTL; HAA, hidróxido de cálcio P.A. com Aloe vera e água destilada; HAL, hidróxido de cálcio P.A. com Aloe vera, água destilada e FTL. A avaliação da citotoxicidade sucedeu-se com o reagente MTT em 24, 48 e 72 h e, para avaliação da genotoxicidade utilizou-se o teste de micronúcleo em 24 h. Em 24 h, o grupo CL apresentou a maior média de viabilidade celular, e o HA mostrou menor média mas estimulou maior número de divisão celular. Em 48 h, o grupo CL apresentou a maior média de viabilidade celular apesar da elevada genotoxicidade, e o HAL mostrou menor média. O grupo AL demonstrou maior percentual de células sobreviventes em 72 h com diferença estatística dos grupos HA e HL (p<0,05). O grupo AL exibiu alta genotoxicidade tendo resultados significantes quando em comparação com o grupo CTR (p<0,001) e ao grupo AA (p<0,01). Conclui-se que a Aloe vera permitiu uma maior viabilidade celular em fibroblastos pulpares humanos na presença do hidróxido de cálcio, contudo houve aumento da genotoxicidade nessa associação. Já o hidróxido de cálcio e a FTL apresentaram maior citotoxicidade.

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Vasconcelos, Inácio Ricardo Alves. "Investigação dos efeitos antibacteriano, antioxidante, citotóxico e genotóxico do óleo essencial do caule de Croton tricolor Klotzsch ex Baill." Universidade Federal da Paraíba, 2015. http://tede.biblioteca.ufpb.br:8080/handle/tede/8639.

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The use of natural products by man goes back to the origins of the human species, which over the evolutionary process, was learning how to select plants for their food and for the relief of their ailments and diseases. Essential oils are complex organic constituents produced by aromatic plants as secondary metabolites, known for its medicinal properties. Croton tricolor Klotzsch ex Baill is a species belonging to Euphorbiaceae family, with antimicrobial and antioxidant properties. This study aimed to evaluate the antibacterial activity against Gram positive bacterial strains (Staphylococcus aureus) and Gram-negative (Escherichia coli), as well as antioxidant activity, cytotoxic and genotoxic of the essential oil of C. tricolor stem (Ct-OEc). The antibacterial activity was evaluated by determining the minimum inhibitory concentration (MIC) by the broth microdilution technique and characterization of the bactericidal effect by plating and spectrophotometry. The oxidant and antioxidant activities were determined in human blood type O erythrocytes in the absence and presence of phenylhydrazine. The in vitro cytotoxicity was determined by quantification of the hemolysis against human red cells of blood types A, B and O. The investigation of genotoxicity in vivo was performed using the micronucleus test in Swiss mice. The results indicate the presence of antimicrobial activity Ct-OEC front strains of S. aureus ATCC 25925 and E. coli ATCC 2536, E. coli ATCC 8539, E. coli 101 and E. coli 105 at a concentration of 1 mg. ml-1 (MIC). The Ct-OEc has no oxidizing effect at the concentrations tested and displays antioxidant effect at the concentration of 1000μg/mL. In evaluating the genotoxic potential by micronucleus test in mice, it was found that Ct-OEC not led to increased frequency of micronuclei in the peripheral blood of mice. Thus it was concluded that the essential oil of Croton tricolor has antibacterial activity, no effects on cell membrane, in low concentrations, without inducing oxidative, has antioxidant activity, without aneugenic and clastogenic effects.
A utilização de produtos naturais pelo homem remonta às origens da espécie humana, que ao longo do processo evolutivo, foi aprendendo a selecionar plantas para a sua alimentação e para o alívio de seus males e doenças. Óleos essenciais são constituintes orgânicos complexos, produzidos por plantas aromáticas como metabólitos secundários, conhecidos por suas propriedades medicinais. Croton tricolor Klotzsch ex Baill pertencente a família Euphorbiaceae com propriedades antimicrobiana e antioxidante. Este estudo objetivou avaliar a atividade antibacteriana frente a linhagens bacterianas Gram positivas (Staphylococcus aureus) e Gram negativas (Escherichia coli), bem como as atividades antioxidante, citotóxica e genotóxica do óleo essencial do caule de C. tricolor (Ct-OEc). A atividade antibacteriana foi avaliada através da determinação da concentração inibitória mínima (CIM) pela técnica de microdiluição e a caracterização do efeito bactericida por plaqueamento e espectrofotometria. A citotoxicidade in vitro, foi determinada pela quantificação da hemólise frente a eritrócitos humanos dos tipos sanguíneos A, B e O. A investigação da genotoxicidade in vivo foi realizada através do teste de micronúcleo em camundongos Swiss. Os resultados obtidos indicam a presença de atividade antibacteriana do Ct-OEc frente as cepas de S. aureus ATCC 25925 e E. coli ATCC 2536, E. coli ATCC 8539, E. coli 101 e E. coli 105 na concentração de 1 mg.mL-1 (CIM). O Ct-OEc não apresenta efeito oxidante nas concentrações testadas e apresenta efeito antioxidante na concentração de 1000μg/mL. A avaliação da atividade hemolítica do Ct-OEc frente aos eritrócitos humanos dos grupos sanguíneos A, B e O promoveu hemólise de baixa a moderada até a concentração de 100 μg/mL. Na avaliação do potencial genotóxico, através do teste do micronúcleo em camundongos, verificou-se que o Ct-OEc não provocou o aumento da frequência de micronúcleos no sangue periférico dos camundongos. Sendo assim foi concluído que o óleo essencial de Croton tricolor apresenta atividade antibacteriana, sem efeitos sobre a membrana celular, quando em baixas concentrações, sem induzir atividade oxidante, apresenta atividade antioxidante, sem efeitos aneugênicos e clastogênicos.

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Lima, Rafaely Nascimento. "Caracterização química dos óleos essenciais e extratos supercríticos de três espécies de Piper de Sergipe." Pós-Graduação em Química, 2014. https://ri.ufs.br/handle/riufs/6097.

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To contribute to the knowledge of the chemical species P. klotzschianum, P. hispidum and P. arboreum, analyzes of volatile obtained by hydrodistillation-(HD), extracts obtained by supercritical fluid extraction-(SFE) and identification of isolated compounds were performed using techniques such as GC/MS/FID, NMR (1D, 2D) and IV. Sesquiterpenes present in P. klotzschianum, P. hispidum and P. arboreum as the (E)-caryophyllene, bicyclogermacrene and germacrene D observed only in P.hispidum and P. klotzschianum were the main substances responsible for the high values obtained sesquiterpenes identified by HD. For the monoterpenes £]-pinene (27.19¡Ó0.27%) and £-pinene (7.17¡Ó0.50%) identified in the chemical composition of the stems of P. klotzschianum and Ô-3-carene (17.39¡Ó0.15%, 19.13¡Ó0.48%) respectively present in fresh and dry leaves of P. hispidum also deserved highlighted. The highest yield of extract using supercritical carbon dioxide-(SC-CO2) was 1.36% (80 ¢XC/220 bar) P. klotzschianum and 1.92% (80 ¢XC/200 bar) for P. hispidum, already with the addition of modifiers 2.18% for P. klotzschianum and 3.62% P. hispidum both using 5% methanol at 80 ¢XC/220 bar. By analysis of variance and F test the cosolvent was the variable that most influenced the yields of extracts for F = 288.95 (P. klotzschianum) and F = 409.59 (P.hispidum). The major compounds identified by GC/MS/FID of P. hispidum using SC-CO2 and SC-CO2 + co-solvents were germacrene D (21.08%-80 ¢XC/200 bar-isopropanol 1%) and squalene (15.18%-80 ¢X C/200 bar). Four compounds not initially identified by GC/MS/FID were isolated from extracts of SC-CO2 by column-chromatography (CC) followed by preparative layer chromatography-(CCDP): N-[3-(6-methoxy-3´, 4´-methylenedioxyphenyl)-2(Z)-propenoyl]-pyrrolidine (PHC7_1), N-[3-(6´-methoxy-3´, 4´-methylenedioxyphenyl)-2 (E)-propenoyl]-pyrrolidine (PHC7_2), N-[7 (3´, 4´ methylenedioxyphenyl)-2(Z), 4(E)-heptadienoil]-pyrrolidine (PHC6_2) and N-[7 (3´, 4´ methylenedioxyphenyl)-2(E), 4(Z)-heptadienoil]-pyrrolidine (PHC9), among these only PHC7_1 was cited in the literature on P. hispidum, the others were first reported in the species, with an PHC6_2 PHC9 unpublished in the literature. In chemical composition of the extracts of P. klotzschianum, germacrene D (25.00¡Ó0.11%-40 ¢XC/220 bar/isopropanol 3%), bicyclogermacrene (15.41¡Ó0.23%-40 ¢XC/220 bar/isopropanol 3%), 14-oxy-muuroleno-£ (21.23¡Ó0.10%-80 ¢XC/180 bar/ethanol 3%) pipercalosidina (22.06¡Ó0.01%-40 ¢XC/180 bar/methanol 1%) and (E)-caryophyllene (11.66¡Ó0.05%-40 ¢XC/220 bar/isopropanol 3%) are the major constituents present in the extracts obtained with SC-CO2 or addition modifier. Among the samples tested in front of IC50 HepG2 and HL-60 cells, the samples P. hispidum stems oil (94.77¡Ó1.93%-HepG2), P. klotzschianum fruit oil (90.53¡Ó1.10%-HepG2, 76.64¡Ó7.44%-HL-60) and P. klotzschianum oil fresh leaves (93.24¡Ó0.70%-HepG2) had cytotoxic activity. The oil obtained from the dried leaves of P. klotzschianum (122.372¡Ó1.247 £gg mL-1), dried leaves of P. hispidum (141.876¡Ó2.333 £gg mL-1), fresh leaves of P. arboreum (187.901¡Ó2.106 £gg mL-1) and fresh leaves P. klotzschianum (223.051¡Ó1.253 £gg mL-1) showed larvicidal activity against the mosquito Aedes aegypti.
Visando contribuir para o conhecimento quimico das especies P. klotzschianum, P. hispidum e P. arboreum, analises dos volateis obtidos por hidrodestilacao-(HD), extratos obtidos por extracao com fluido supercritico-(EFS) e identificacao de compostos isolados foram realizadas por tecnicas como CG/EM/DIC, RMN (1D, 2D) e IV. Sesquiterpenos presentes na P. klotzschianum, P. hispidum e P. arboreum como o (E)-cariofileno, biciclogermacreno e o germacreno D observados somente na P. klotzschianum e P. hispidum foram as principais substancias responsaveis pelos altos percentuais de sesquiterpenos identificados obtidos por HD. Para os monoterpenos o £]-pineno (27,19¡Ó0,27%) e £-pineno (7,17¡Ó0,50%) identificados na composicao quimica dos caules de P. klotzschianum e Ô-3-careno (17,39¡Ó0,15%-19,13¡Ó0,48%) respectivamente presente nas folhas frescas e folhas secas da P. hispidum mereceram destaque. O maior rendimento de extrato utilizando dioxido de carbono supercritico-(SC-CO2) foi 1,36% (80 ¢XC/220 bar) P. klotzschianum e 1,92% (80 ¢XC/200 bar) para a P. hispidum, ja com adicao de modificadores 2,18% para a P. klotzschianum e 3,62% para a P. hispidum ambas utilizando 5% de metanol a 80 ¢XC/220 bar. Pela analise de variancia e teste F o co-solvente foi a variavel que maior influenciou para os rendimentos dos extratos F=288,95 (P. klotzschianum) e F=409,59 (P.hispidum). Os constituintes majoritarios identificados por CG/EM/DIC para a P. hispidum utilizando SC-CO2 e SC-CO2 + co-solventes foram o germacreno D (21,08%-80 ¢XC/200 bar- isopropanol 1%) e o esqualeno (15,18%-80 ¢XC/200 bar). Quatro substancias inicialmente nao identificadas por CG/EM/DIC foram isoladas dos extratos de SC-CO2 por meio de cromatografia em coluna-(CC) seguida de cromatografia em camada preparativa-(CCDP) N-[3-(6¡¦-metoxi-3¡¦,4¡¦-metilenodioxifenil)-2(Z)-propenoil]-pirrolidina (PHC7_1), N-[3-(6¡¦-metoxi-3¡¦,4¡¦-metilenodioxifenil)-2(E)-propenoil]-pirrolidina (PHC7_2), N-[7(3¡¦,4¡¦ metilenodioxifenil)-2(Z),4(E)-heptadienoil]-pirrolidina (PHC6_2) e N-[7(3¡¦,4¡¦ metilenodioxifenil)-2(E),4(Z)-heptadienoil]-pirrolidina (PHC9), dentre estas apenas a PHC7_1 foi citada na literatura sobre P. hispidum, as demais foram relatadas pela primeira vez na especie, sendo a PHC6_2 e PHC9 ineditas na literatura. Na composicao quimica dos extratos da P. klotzschianum o germacreno D (25,00¡Ó0,11%-40 ¢XC/220 bar/isopropanol 3%), biciclogermacreno (15,41¡Ó0,23%-40 ¢XC/220 bar/isopropanol 3%), 14-oxi-£-muuroleno (21,23¡Ó0,10%-80 ¢XC/180 bar/etanol 3%), pipercalosidina (22,06¡Ó0,01%-40 ¢XC/180 bar/metanol 1%) e (E)-cariofileno (11,66¡Ó0,05%-40¢XC/220 bar/isopropanol 3%) foram os constituintes majoritarios presentes nos extratos obtidos com SC-CO2 ou com adicao de modificadores. Dentre as amostras testadas na IC50 frente as celulas HepG2 e HL60 as amostras P. klotzschianum oleo dos caules (94,77¡Ó1,93%-HepG2), P. klotzschianum oleo dos frutos (90,53¡Ó1,10%-HepG2, 76,64¡Ó7,44%-HL60) e P. klotzschianum oleo das folhas frescas (93,24¡Ó0,70%-HepG2) apresentaram atividade citotoxica. Os oleos obtidos das folhas secas da P. klotzschianum (122,372¡Ó1,247 £gg mL-1), folhas secas da P. hispidum (141,876¡Ó2,333 £gg mL-1), folhas frescas da P. arboreum (187,901¡Ó2,106 £gg mL-1) e folhas frescas da P. klotzschianum (223,051¡Ó1,253 £gg mL-1) apresentaram atividade larvicida contra o mosquito Aedes aegypti.

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34

Erdelyi, Maria Carolina. "Contribuição à farmacognosia de Annona squamosa L. (Annonaceae) - Acompanhamento da variação sazonal de constituintes, aspectos botânicos e avaliação da atividade antileishmania in vitro." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/9/9138/tde-14092017-114936/.

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As doenças tropicais endêmicas representam um grave problema sócio-econômico, no Brasil e no mundo. A leishmaniose insere-se neste quadro. Considerando o surgimento da resistência dos parasitas e a séria toxicidade da terapêutica convencional, a busca de novas alternativas é urgente. A família Annonaceae tem mostrado ser rica fonte de compostos com atividade antiprotozoária. Neste contexto, Annona squamosa L. foi selecionada. Sendo mais conhecida como \"fruta-do-conde\", apresenta uso na medicinal popular, como: antihelmíntica e no combate aos ectoparasitas. Entre os principais metabólitos secundários da espécie, citam-se: alcalóides isoquinolínicos, acetogeninas, flavonóides e óleo volátil. A atividade biológica de A. squamosa tem sido investigada, entretanto, aquela referente à ação antileishmania permaneceu inexplorada, até o presente trabalho, no qual foram avaliadas amostras referentes aos alcalóides totais, ao extrato hidroetanólico, aos infusos e frações orgânicas dos extratos obtidos, a partir de: folhas, pericarpos, sementes e arilos, coletados em quatro fases anuais. Os ensaios in vitro foram realizados frente às formas promastigotas de Leishmania amazonensis, tendo-se realizado, em paralelo, avaliação da citotoxicidade in vitro frente a células epiteliais humanas. Os mesmos extratos foram submetidos ao estudo químico para acompanhamento da variação sazonal qualitativa e quantitativa de classes de componentes e seus marcadores, selecionados por sua ação antileishmania potencial. As análises abrangeram alcalóides, flavonóides, polifenóis totais e taninos, tendo-se empregado as técnicas cromatográficas (CLAE, CCD) e a espectrofotométrica. Em complementação, efetuou-se o estudo morfoanatômico de folha. Os resultados serviram de estímulo para a continuidade do estudo visando ao isolamento de compostos bioativos.
Leishmaniasis, as well as other protozoal tropical endemic diseases, remains a serious Public Health problem all over the world. New altematives for their treatment are urgently needed, since the parasite resistance is increasing and the high toxicity of the conventional medicines reduces its patient adherence. In last decades, several vegetal species from the Annonaceae family showed to be a rich source of potential antiprotozoal metabolites. Therefore, Annona squamosa L. was selected. Although is largely known for its fleshy and flavorous fruits called \"pinhas\" and \"fruta do conde\", some medicinal properties have been attributed to different plant parts including the antihelminthic and against ectoparasites. The main secondary metabolites found in the species were: isoquinoline alkaloids, acetogenins, flavonoids and volatil oil. In this work, the in vitro antileishmanial activity was investigated for the total alkaloid and hidroalcoholic extracts, infuses and organic fractions from leaves, fruits, seeds and arils of A.squamosa collected in the four anuual phases. In vitro tests were also performed to evaluate the cytotoxic activity of extracts. Qualitative or quantitative analyses of alkaloids, total phenolics, total flavonoids and tannins were done by HPLC, spectrophotometric and TLC methods. The morphoanatomical study of leaves was also presented and illustrated by photos and photomicrographies. The results have encouraged deeper researches and further isolation of bioactive compounds.

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35

AHMAD, NURIE AHMAD. "Contribution a l'etude de la croissance et de la toxinogenese du genre fusarium (link) sur mais apres recolte." Nantes, 1986. http://www.theses.fr/1986NANT2036.

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La premiere partie des travaux a porte sur la mise au point des methodes permettant le dosage de cinq toxines du groupe des trichothecenes. Les methodes mises au point concernent les toxines responsables de contaminations naturelles; t2-toxine, ht2-toxine, t2-tetraol, diacetoxyscirpenol, deoxynivalenol. L'etude de modalites des biosyntheses de ces toxines a ete precedee de differents essais preliminaires: une trentaine de souches, appartenant a une dizaine d'especes fusariennes frequentes sur mais en france, ont ete examinees pour leur aptitude a la synthese des trichothecenes. Deux especes caracteristiques (f. Lateritium et f. Sporotrichioides) ont ete retenues et etudiees en detail

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36

DERRIEN, Anne-Cécile. "Synthèse et caractérisation physico-chimique de matériaux géopolymères. Application : cinétique de minéralisation de géopolymères et du biomatériau CaCO3 synthétique." Phd thesis, Université Rennes 1, 2004. http://tel.archives-ouvertes.fr/tel-00007911.

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Dans le domaine de la chirurgie orthopédique ou maxillo-faciale, les praticiens sont confrontés à des pertes de substance osseuse qui nécessitent l'utilisation de matériaux de comblement (ou de substitution). L'utilisation de biomatériaux synthétiques (dont la disponibilité est très importante) permet de limiter les réponses immunitaires. Dans ce travail nous nous intéressons à deux matériaux : les géopolymères et le carbonate de calcium synthétique sous forme d'aragonite pure. Dans le domaine des biomatériaux de comblement, l'optimisation du compromis entre le pourcentage de porosité et les propriétés mécaniques (voisines de celles de l'os spongieux) favorise l'ostéointégration et la tenue des implants. Cette observation nous a conduit à étudier des aluminosilicates de la famille des géopolymères définis par un rapport molaire Si/ Al = 21. Les aluminosilicates synthétisés ont été associés à des phosphates de calcium : hydroxyapatite (HA), phosphate tri-calcique (TCP) et biphasique. Après traitement thermique à 500°C, les géopolymères présentent des valeurs de pH voisines de 7 ainsi qu'un bon compromis porosité/ contrainte à la rupture (en compression). Pour le CaCO3, notre laboratoire de recherches a mis au point la synthèse du carbonate de calcium sous forme d'aragonite pure. Ces matériaux ont fait l'objet d'études in vitro et in vivo afin d'évaluer leur potentiel pour une utilisation comme biomatériaux. Les cinétiques de minéralisation des implants géopolymères et du biomatériau CaCO3 ont été étudiées par PIXE (Proton Induced X-Ray Emission) et par NAA (Neutron Activation Analysis). Les résultats obtenus pour le CaCO3 par ces deux méthodes montrent un comportement in vivo similaire à celui d'un TCP utilisé comme référence (travail réalisé avec l'aide de l'ANVAR Bretagne). Les premières études in vivo réalisées sur les géopolymères ont montré que ces derniers sont ostéointégrés. Dès le délai de 1 mois, les porosités externes des implants sont colonisées par de l'os néoformé. La cicatrisation en surface des matériaux est totale à 3 mois. Les analyses par PIXE des implants confirment la consolidation de l'interface dès le délai de 1 mois.

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37

Chen, Yi-Lun, and 陳宜倫. "Study on a Plant Product, THKM76: Cytotoxicity and Cell Cycle Effect." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/04684269170185130156.

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碩士
國立清華大學
生命科學系
88
Many anticancer agents are currently available for clinical therapy, but very few agents are effective against some types of cancer. Fortunately, we have obtained a potential anticancer agent THKM76 from a plant product. In this purpose, we studied the effects of THKM76 on the morphology, cytotoxicity, and cell cycle progression in a human colon adenocarcinoma cell line (RKO) and a human fibroblast cell line (HF). For RKO cells, characteristic morphological changes and drug-induced apoptosis, related to the administration of the cytotoxic agent, were interpreted as degenerative in nature, but drug-treated HF cells revealed less characteristic features of damage. Cytotoxicity was evaluated by clonogenic survival assay showed that RKO was more sensitive to THKM76 than HF. In addition, by MTT assay, we found that treating the cells with THKM76 resulted in a decrease of cell viability in a dose- and a time-dependent manner. However, there were differences in survival rate between using clonogenic survival assay (assayed after release 7 days) and MTT assay (assayed immediately after exposure). According to the results and some evidences indicated that the cell growth delayed after release from treatment, we demonstrated that there were two major cytotoxic effects for inducing cell killing. (i) Direct effect: Cells were killed first during THKM76 treatment. (ii) Persisted effect: After removal of THKM76, drug-treated viable cells lost reproductive ability further and even died. Finally, flow cytometry analysis of the DNA content revealed G1 block, slight G2/M arrest, and the presence of a ‘sub-G2’ region in RKO cells after THKM76 treatment with indicated concentrations. Besides, after release from treatment, there was a significant increase of RKO cells arrested in G2/M phase. The results of combining the arrest status with irradiation supported a role for THKM76 as a radiosensitizer.

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38

Wu, Tzu-Min, and 吳慈敏. "Size Distributions and Cytotoxicity of Ambient Aerosols Collected Near a Semiconductor Plant." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/45715067978685890933.

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碩士
國立屏東科技大學
環境工程與科學系所
100
In this study, PS-1, Dichot, MOUDIs and Nano-MOUDIs were used to collect TSP, PM2.5-10, PM2.5, PM0.01-10 (as PM10 thereafter), PM0.01-2.5 (as PM2.5), PM0.01-1 (as PM1.0), PM0.01-0.1 (as PM0.1) and PM0.01-0.056 (as PM0.056) samples on the rooftops of a semiconductor plant and a wastewater treatment plant (48.9 and 16 m high, respectively) (from March to September, 2011) in a Southern Taiwan Science Park to characterize the size distributions of sampled particles and the cytotoxicity of particle extracts. In addition to the analyses of particulate water-soluble ions, carbon, and PAHs, human male single cells (U937) and the method MTT(3- (4, 5dimethyl-thiazol-2-yl)-2, 5-diphenyltetrazolium bromide) were utilized to test the cytotoxicity of particle extracts obtained via water and organic-solvent extractions. The results showed that the atmospheric PM2.5/PM10 values of semiconductor plant was lower during air pollution episode days and general sunny days (0.67 and 0.63, respectively), while the corresponding ratio was higher on sunny days after raining (0.74). Although the PM10 concentration on sunny days after raining was about 0.57 time that on general sunny days, the PM0.1 and PM0.056 concentrations after raining increased by 1.20 and 1.34 times, respectively, when compared with that on general sunny days. Moreover, the ratios of PM0.1/PM10 and PM0.056/PM10 on sunny days after raining were 2.2 and 2.7 times those on general sunny days. The atmospheric particles were approximately bi-modal distributed, with a main peak in fine mode (0.32–1 µm) and a secondary peak in coarse mode (2.5–5.6 µm). About 30–50% of PM2.5 and 29–39% of PM2.5-10 were water-soluble ions. The primary species of water-soluble ions were secondary aerosols, such as SO42-, NO3- and NH4+ (more than 80%). In PM2.5, the concentration and content of SO42- were the highest, while in PM2.5-10, NO3- had the highest concentration and content. About 33–40% of atmospheric TSP in the park was contributed by carbon species, and the OC/EC value was 1.89–2.23. About more than 97% (96.9−98.5%) of total metallic concentrations in PM0.056, PM0.1, PM1, PM2.5 and PM2.5-10 were contributed by Na, Mg, Al, K, Ca, Fe, Ni, and Zn. The at emiconductor plant exhibited the highest average concentration of PAHs in atmospheric TSP during air pollution episode days. On both general sunny days and sunny days after raining, the PAHs in PM10 mainly distributed in fine particles (PM2.5). For the samples taken on the roof of semiconductor plant, the cytotoxicity of water-soluble extracts from differently sized atmospheric particles was higher on general sunny days than on sunny days after raining. Such cytotoxicity was higher in PM0.32-1.8 (particles with the size ranges 0.32–0.56, 0.56–1.0, and 1.0–1.8 μm). Moreover, the cytotoxicity of particle organic-solvent extract was higher for PM2.5 than for PM2.5-10. The cytotoxicity of water extract of TSP collected in different periods was in order episode days > general sunny days > sunny days after raining.

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39

Chou, Chi-Jung, and 周奇蓉. "Studies on the Chemical Constituents and Cytotoxicity of the Seeds of Formosan Annonaceous Plant - Annona muricata." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/21728336200448344316.

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碩士
高雄醫學大學
天然藥物研究所
88
Twenty eight compounds including twenty mono-THF ring acetogenins, annonacin (1), annonacinone (2), annomontacin (3), cis- annomontacin (4), xylopiacin (5), murisolin (6), muricatetrocin A (7) & B (8), muricin A (9), muricin B (10), muricin C (11), muricin D (12), muricin E (13)、muricin F (14), muricin G (15), longifolicin (16), corossolin (17), corossolone (18), muricin H (19) and muricin I (20), one adjacent bis-THF rings acetogenin, annocatacin B (21), one linear acetogenin, cohibin A (22), one epoxyl acetogenin, epomuricin (23), one amide, N-palmitryltryptamine (24) and four steroids, b-sitosterol (25), stigmasterol (26), b-sitosteryl-D-glucoside (27) and stigmasteryl-D-glucoside (28) have been isolated from the seeds of Formosan Annona muricata. All isolates were characterized by spectral and chemical analysis. Among them, 4, 9-15 and 19-22 are new compounds. In addition, compounds 3, 5, 16 and 24, first isolated form the plant, are rather significant evidence in chemotaxonomy of Annonaceae. Among these acetogenins, except compounds 13, 15 and 22, were tested for their cytotoxicity against Hep G2 and Hep 2,2,15 cell lines (human hepatoma cells). Compounds 1, 3, 7-11, 14 and 16 exhibited potent cytotoxicity against Hep 2,2,15 cell line with IC50 3.82 ´ 10-3~5.13 ´ 10-3mg/mL. In addition, compounds 5, 12 and 16 also showed significant cytotoxicity with IC50 3.43 ´ 10-3, 6.60 ´ 10-4 and 4.04 ´ 10-4 mg/mL, respectively against Hep G2 cell line. For searching bioactive constitutents of the seeds of Annona muricata, several new acetogenins were isolated. The structural elucidation and biological activities are discussed in detail. The acetogenins could well make them become the next class of useful antitumor agents.

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40

Taiwo, Bamigboye J., Amos A. Fatokun, O. O. Olubiyi, O. T. Bamigboye-Taiwo, Heerden F. R. van, and Colin W. Wright. "Identification of compounds with cytotoxic activity from the leaf of the Nigerian medicinal plant, Anacardium occidentale L. (Anacardiaceae)." 2017. http://hdl.handle.net/10454/11940.

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Yes
Cancer is now the second-leading cause of mortality and morbidity, behind only heart disease, necessitating urgent development of (chemo)therapeutic interventions to stem the growing burden of cancer cases and cancer death. Plants represent a credible source of promising drug leads in this regard, with a long history of proven use in the indigenous treatment of cancer. This study therefore investigated Anacardium occidentale, one of the plants in a Nigerian Traditional Medicine formulation commonly used to manage cancerous diseases, for cytotoxic activity. Bioassay-guided fractionation, spectroscopy, Alamar blue fluorescence-based viability assay in cultured HeLa cells and microscopy were used. Four compounds: zoapatanolide A (1), agathisflavone (2), 1, 2-bis (2,6-dimethoxy-4-methoxybenzoyl) ethane (Anacardicin, 3) and methyl gallate (4) were isolated, with the most potent being zoapatanolide A with an IC50 value of 36.2 ± 9.8 μM in the viability assay. To gain an insight into the likely molecular basis of their observed cytotoxic effects, Autodock Vina binding free energies of each of the isolated compounds with seven molecular targets implicated in cancer development (MAPK8, MAPK10, MAP3K12, MAPK3, MAPK1, MAPK7 and VEGF), were calculated. Pearson correlation coefficients were obtained with experimentally-determined IC50 in the Alamar blue viability assay. While these compounds were not as potent as a standard anti-cancer compound, doxorubicin, the results provide reasonable evidence that the plant species contains compounds with cytotoxic activity. This study provides some evidence of why this plant is used ethnobotanically in anti-cancer herbal formulations and justifies investigating Nigerian medicinal plants highlighted in recent ethno-botanical surveys.
This work was supported by a British Council Researcher Links Travel Grant 2013 to TBJ, a South Africa’s National Research Foundation (NRF) Grant No 98345, 2016 to FRVH and an academic staff funding provided to AAF by the School of Pharmacy, University of Bradford, UK.

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41

Félix, Carina Rafaela Faria da Costa. "Multi-omics approach to study responses to temperature in Lasiodiplodia theobromae, a human and plant fungal pathogen." Doctoral thesis, 2018. http://hdl.handle.net/10773/26082.

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Lasiodiplodia theobromae is a phytopathogenic fungus considered an aggressive pathogen, especially for some crops, and has also been associated to opportunistic human infections. Small environmental alterations, such as the increasing of the global temperature, can have a huge impact on the dynamic between hosts and their pathogens, leading to changes in virulence or even to the colonization of different hosts. Thus, the main goal of this work was to characterize the molecular mechanisms of pathogenicity of L. theobromae under increasing temperatures. To achieve this, a multi-omics approach – genomics, transcriptomics, proteomics and metabolomics – was used. This holistic approach was complemented with targeted strategies (enzymatic profiling and cytotoxicity evaluation). In a general way, an investment of the fungus in dissemination was found when grown at 25 °C, with higher expression of transcripts/proteins associated to primary and carbohydrate metabolism and pathogenesis. At 37 °C, a selfprotection state seems to be used by this species, with an over expression of transcripts/proteins related to stress response. However, temperature- and strain-specific virulence factors were identified. Several transcripts/proteins/metabolites known to participate in the penetration, colonization and dissemination of the pathogen inside the plant and human hosts were identified. Between them, enzymes responsible to degrade the cell wall and molecules involved in pathways that contribute to a successful penetration inside the host, as MAPKs, were identified. Helping to overcome the stress originated by the host, heat shock proteins and nudix effectors were also identified. Proteins from velvet complex, important for fungal development and regulation of secondary metabolism, were also expressed. It seems that there is a tendency of the human isolated strain CBS339.90 to be more aggressive at 37 °C, expressing several molecules known to participate in human infections and being responsible for high rates of mammalian cell mortality. Contrarily, the strains isolated from plants, presented more transcripts/proteins related with pathogenesis at 25 °C and were more toxic for the tomato cuttings, at this temperature. This work attests the usefulness of using a multi-omics strategy to dissect fungal molecular pathogenesis mechanisms as well as differences between strains and temperatures, contributing to unveil the ability of this species to colonize a wide range of environments and hosts from different kingdoms.
Lasiodiplodia theobromae é um fungo fitopatogénico considerado agressivo, sobretudo para algumas culturas, que tem sido também associado a infeções oportunistas em humanos. Pequenas alterações ambientais, como o aumento da temperatura global, podem ter grande impacto na dinâmica entre hospedeiros e agentes patogénicos, levando a alterações na virulência ou mesmo à colonização de novos hospedeiros. Assim, o objetivo principal deste trabalho consistiu em caraterizar os mecanismos moleculares de patogenicidade de L. theobromae sob diferentes temperaturas. Para atingir este objetivo utilizou-se uma abordagem multi-ómica – genómica, transcriptómica, proteómica e metabolómica. Esta abordagem holística foi ainda complementada com outras estratégias específicas (perfil enzimático e avaliação da citotoxicidade). De uma forma geral, o fungo investe mais recursos energéticos na sua disseminação quando é cultivado a 25 °C, apresentando uma maior expressão de transcritos/proteínas associados ao metabolismo primário e de carboidratos, e também de patogénese. A 37 °C esta espécie parece concentrar-se mais na sua proteção, apresentando uma sobre-expressão de transcritos/proteínas relacionados com resposta ao stress. Foram identificados vários transcritos/proteínas/metabolitos conhecidos por participar na penetração, colonização e disseminação do agente patogénico no hospedeiro, plantas e humanos. Entre eles, enzimas responsáveis pela degradação da parede celular vegetal e moléculas envolvidas em vias que contribuem para uma penetração do hospedeiro bem sucedida, como vias MAPKs. Foram também identificadas proteínas de choque térmico e efetores nudix, responsáveis por ajudar a ultrapassar o stress originado pelo hospedeiro e proteínas do complexo velvet, importantes no desenvolvimento do fungo e na regulação do metabolismo secundário. Parece existir uma tendência para que a estirpe CBS339.90, isolada a partir de um humano, seja mais agressiva a 37 °C, expressando várias moléculas conhecidas por participar em infeções em humanos e sendo responsável por elevadas taxas de mortalidade de células de mamíferos. Contrariamente, as estirpes isoladas de plantas apresentaram mais transcritos/proteínas relacionados com patogénese a 25 °C e maior toxicidade em tomateiros também a esta temperatura. Este trabalho atesta a utilidade da utilização de uma abordagem multi-ómica para dissecar o mecanismo molecular de patogénese de fungos, assim como as diferenças encontradas entre as estirpes e as suas respostas à temperatura ambiental, contribuindo para desvendar a capacidade desta espécie em colonizar uma vasta gama de ambientes assim como hospedeiros de diferentes reinos.
Programa Doutoral em Biologia

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42

Adewusi, Emmanuel Adekanmi. "In vitro effect of selected medicinal plants on β-amyloid induced toxicity in neuroblastoma cells." Thesis, 2012. http://hdl.handle.net/2263/28325.

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Neurodegenerative diseases occur as a result of the breakdown and deterioration of the neurons of the central nervous system (CNS). They are commonly found in elderly people and are a major cause of morbidity and mortality, thereby imposing severe strains on the social welfare systems. Alzheimer’s disease (AD) is the most common age-related neurodegenerative disorder. Cholinergic deficit, senile plaque/amyloid-β peptide deposition and oxidative stress have been identified as three main pathogenic pathways which contribute to the progression of AD. The current therapeutic options cause several side-effects and have problems associated with bioavailability. Therefore, the need arises to search for new compounds from natural products with potential to treat AD. Seventeen plants were selected for this study based on their documented ethno-medicinal use in improving memory, to treat insomnia, calm agitated people, and other neurological disorders. The plants were screened for inhibition of acetylcholinesterase (AChE) using the TLC and microtiter plate method. A dose-dependent inhibition of the enzyme was observed and 4.5% of all the plants showed low (<30% inhibition) AChE inhibition. The ethyl acetate extracts of the roots of Crinum bulbispermum, Xysmalobium undulatum, Lannea schweinfurthii, Scadoxus puniceus and bulbs of Boophane disticha had the best AChE inhibition. Although the IC50 of these plant extracts were higher than that of the positive control, galanthamine (0.00053 mg/ml), they showed good AChE inhibitory activity considering they are still mixtures containing various compounds. The antioxidant activity of the plant extracts was determined by their ability to scavenge ABTS (2,2´-azinobis-3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (1,1-diphenyl-2-picryl- hydrazyl) radicals. The dichloromethane/methanol (1:1) extracts of Chamaecrista mimosoides (root), Buddleja salviifolia (whole plant), Schotia brachypetala (root and bark), water extracts of Chamaecrista mimosoides (root), Buddleja salviifolia (whole plant), Schotia brachypetala (root and bark) and methanol extracts of the roots of Crinum bulbispermum, Piper capense, Terminalia sericea, Lannea schweinfurthii and Ziziphus mucronata all showed good antioxidant activity (>50%), in both assays. B. disticha contained very promising AChE inhibition and was subjected to isolation of active compounds using thin layer chromatography, column chromatography and preparative thin layer chromatography. Two compounds, 6-hydroxycrinamine (a crinine-type alkaloid) and cycloeucalenol (a cycloartane triterpene), were isolated for the first time from the bulbs of this plant. 6-Hydroxycrinamine, and two fractions, EAM 17-21 21,22 and EAE 11 (which could not be purified further due to low yield), were found to inhibit AChE with IC50 values of 0.445 ± 0.030 mM, 0.067 ± 0.005 mg/ml and 0.122 ± 0.013 mg/ml, respectively. Cytotoxicity of the isolated compounds and two active fractions was determined on human neuroblastoma (SH-SY5Y) cells using the MTT and neutral red uptake assays. 6- hydroxycrinamine and fraction EAM 17-21 21,22 were found to be toxic with IC50 values of 54.5 μM and 21.5 μg/ml as determined by the MTT assay. The isolated compounds and fractions did not show any protective effect against cell death induced by Aβ25-35 possibly due to the poor antioxidant activity of B. disticha bulbs. Cytotoxicity was also determined for the methanol extracts of the roots of C. bulbispermum, T. sericea, L. schweinfurthii and Z. mucronata, as they contained promising antioxidant activity. C. bulbispermum was the most toxic, reducing cell viability by <40% at the highest concentration tested. Z. mucronata and L. schweinfurthii were the least toxic with IC50 values exceeding 100 μg/ml, the highest concentration tested. Three concentrations of the plant extracts that were not toxic, or presented low toxicity, were selected to evaluate their possible protective effect against cell death induced by Aβ25-35. Pretreatment with Z. mucronata and T. sericea roots showed a dose dependent inhibition of cell death caused by Aβ25-35. Pre-treatment with L. schweinfurthii roots resulted in an optimum dose for inhibition of Aβ25-35 induced cell death at 25 μg/ml, while still maintaining 80% viability. The roots of C. bulbispermum at non-toxic dose still maintained >50% viability. This study confirms the neuroprotective potential of some of the plants which had AChE inhibitory and antioxidant activity. In addition, four of the plants were shown to prevent cell death caused by Aβ25-35. These plants can serve as potential leads in developing drugs relevant to treatment of AD. Furthermore, two new compounds present in the bulbs of B. disticha were identified. Additional investigations need to be carried out by applying QSAR studies to modify the structure of the alkaloid with the aim of reducing its observed toxicity.
Thesis (PhD)--University of Pretoria, 2012.
Pharmacology
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43

Thorburn, Anzelle. "Phytochemical analysis and antimicrobial activity of Piper capensis L.f." Diss., 2011. http://hdl.handle.net/2263/25752.

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Medicinal plants are the focus of intense study, in particular whether their traditional uses are supported by real pharmacological effects, or merely based on folklore. Piper capense L.f. (Piperaceae) is used traditionally for the treatment of infectious diseases, and has the potential to be a source of novel antimicrobial compound(s). Crude solvent extracts (water, methanol, hexane and acetone) and sequentially extracted subfractions of the root-bark of P. capense were prepared, of which the hexane-soluble subfraction MsAsHs was identified as the most promising antimicrobial subfraction. Phytochemical analyses of the various extracts and subfractions using TLC with numerous mobile phases and compound selective visualising reagents revealed the presence of quinones in all of the crude solvent extracts. Alkaloids, lipids/sterols/steroids, phenolic compounds and amino acids/peptides were detected in select subfractions. Gradient reverse phase HPLC analyses using 0.1% formic acid and methanol indicated three major peaks in MsAsHs. IR spectroscopy indicated that carbonyl and hydroxyl functional groups, and aromatic characteristics were present in the major compound present in MsAsHs. Further analysis using targeted LC-MS Q-TOF and quadrupole LC-MS/MS analyses indicated an empirical formula of C11H8O3. This formula was confirmed for the isolated compound by GC-MS (HP5-MS column) that identified the compound as 5-hydroxy-2-methyl-1,4-naphthoquinone (C11H8O3 MW: 188.18) with 98% certainty using the database. Although 5-hydroxy-2-methyl-1,4-naphthoquinone (also known as plumbagin) is well-known, this is the first time that the presence of this compound is reported in the Piper genus. Antimicrobial activities of P. capense root-bark extracts and the subfractions were determined against Gram-negative and Gram-positive bacteria and a yeast strain using the disk diffusion and broth micro-dilution assays. Antimicrobial activity was observed against Gram-positive bacteria, Gramnegative bacteria as well as a yeast strain, indicating broad spectrum activity. The antimicrobial activities of the crude solvent extracts decreased in the order: acetone > methanol > hexane > water. The MsAsHs subfraction demonstrated the highest antimicrobial activity with an MIC of 29 μg/ml against both Staphylococcus aureus (ATCC 12600) and Candida albicans (ATCC 10231). HPLC eluents of this subfraction that were collected in a drop-wise fashion onto silica TLC plates and assayed by bioautography, indicated that the major compound eluting at 13.6 minutes accounted for most of the antimicrobial activity. Antioxidant activity was observed for the crude water extract, crude methanol extract, crude acetone extract, MsAsAs subfraction as well as the MsAsHs subfraction. Cytotoxicity against mammalian cells in culture was observed for the crude methanol extract, crude acetone extract, crude hexane extract and the MsAsHs subfraction when determined using C2C12 cells as well as resting and PHA stimulated lymphocytes. Stability testing of the MsAsHs subfraction revealed that the antimicrobial compounds found in this subfraction appear to be stable up to 30 days at both 25°C and 40°C when assayed against S. aureus. However, when assayed against C. albicans, there was an increase in antifungal activity from 29 μg/ml to < 7 μg/ml after 30 days at both temperatures tested. This study provides scientific support for the ethnomedical use of the rootbark of P. capense as an antimicrobial. To date, the presence of plumbagin has not been reported in any other plant in the Piper genus. Due to the significant cytotoxic activity against mammalian cells reported in the current study and the mechanism of action of plumbagin, the therapeutic potential of P. capense extracts is very limited due to non-selective cytotoxicity, despite its marked antimicrobial activity.
Dissertation (MSc)--University of Pretoria, 2011.
Pharmacology
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44

AnilaKumar, K. R. "Studies on the effect of plant foods on antioxidant enzyme system and their influnce on the chemically induced cytotoxicity in rats." Thesis, 2002. http://hdl.handle.net/2009/1430.

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45

Mishra, Ritu. "Mechanism of Abrin-Induced Apoptosis and Insights into the Neutralizing Activity of mAb D6F10." Thesis, 2014. http://hdl.handle.net/2005/2787.

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Abrin is a potent toxin obtained from the seeds of Abrus precatorius. It is a heterodimeric glycoprotein consisting of an A and a B subunit linked together by a disulfide bond. The toxicity of the protein comes from the A subunit harboring RNA-N-glycosidase activity which cleaves the glycosidic bond between the ribose sugar and the adenine at position 4324 in 28S rRNA. The depurination of a specific adenine residue at position 4324 results in loss of conformation of the 28S rRNA at the α sarcin/ricin loop to which elongation factor-2 (EF-2) binds, during the transloction step of translation, leading to inhibition of protein synthesis. The B subunit of abrin is a galactose specific lectin. The lectin activity enables the toxin to gain entry inside cells on binding to receptors with terminal galactose. After entering cells, a few molecules of abrin reach the endoplasmic reticulum (ER) via the retrograde transport, where the disulfide bond between the A and the B subunits gets cleaved. Then the A chain escapes into the cytosol where it binds to its target, the α-sarcin loop of the 28S ribosomal RNA and inhibits protein synthesis. Apart from inhibition of protein synthesis, exposure of cells to abrin leads to the loss of mitochondrial membrane potential (MMP) resulting in the activation of caspases and finally apoptosis. However, whether apoptosis is dependent on the inhibition of protein synthesis has not been elucidated. The major objectives of this study are therefore to delineate the signaling pathways involved in abrin-induced apoptosis. The thesis is divided into 4 Chapters: Chapter 1. provides a overview of the general properties of RIPs, with a brief history, classification, trafficking and biological activities of the toxins. This chapter also discusses their potential use in bio-warfare and the treatments available for management of toxicity. Chapter 2 and 3 discuss the results obtained on studies aimed at gaining insights into the signaling pathways involved in abrin-induced apoptosis. Chapter 4 focuses on the research carried out to understand the mechanisms of neutralization of abrin by the mAb D6F10. Towards the first objective, chapter 2 elucidates the role of endoplasmic reticulum (ER) stress signaling in abrin-induced apoptosis using the human T-cell line, Jurkat as a model system. It could be concluded that the inhibition of protein synthesis by the catalytic A subunit of abrin could result in accumulation of unfolded proteins in the ER leading to ER stress which triggers the unfolded protein response (UPR) pathway. The ER resident trans-membrane sensors IRE1 (Inositol-requiring enzyme 1), PERK (PKR-like ER kinase) and ATF6 (Activating transcription factor 6) are the important players of UPR in mammalian cells. These sensors inhibit translation and increase the levels of chaperones to restore protein homeostasis. However, if the ER stress is prolonged, apoptotic pathways get activated to remove severely damaged cells in which protein folding defects cannot be resolved. Recent studies have shown that endoplasmic reticulum (ER) stress induces apoptosis by activating initiater caspases such as caspase-2 and -8 which eventually trigger mitochondrial membrane potential loss and activation of downstream effector capases-9 and -3. Phosphorylation of eukaryotic initiation factor 2α and upregulation of CHOP [CAAT/enhancer binding protein (C/EBP) homologous protein], important players involved in ER stress signaling by abrin, suggested activation of ER stress in the cells. ER stress is also known to induce apoptosis via stress kinases such as p38 MAPK and JNK. Activation of both the pathways was observed upon abrin treatment and found to be upstream of the activation of caspases. However, abrin-induced apoptosis was found be dependent on p38 MAPK but not JNK. We also observed that abrin induced activation of caspase-2 and caspase-8 and triggered Bid cleavage leading to mitochondrial membrane potential loss and thus connecting the signaling events from ER stress to mitochondrial death machinery. Few toxins belonging to the family of ribosome inactivating proteins such as Shiga toxin have been observed to induce DNA damage in human endothelial cells and activate p53/ATM-dependent signaling pathway in mammalian cells. To further investigate the role of abrin on activation of DNA damage signaling pathway, we analysed the phosphorylation of H2AX and ATM, which are markers for double strand DNA breaks. We observed phosphorylation of H2AX and ATM upon abrin treatment but not when cells were pretreated with the broad spectrum pan caspase inhibitor. This study suggested that the DNA damage observed was an indirect effect of caspase-activated DNase. We concluded from the studies in chapter 2 that inhibition of protein synthesis by abrin can trigger endoplasmic reticulum stress leading to mitochondria-mediated apoptosis. Further studies were conducted to understand the dependence of ER stress on inhibition of protein synthesis and are presented in chapter 3. For this study, we have used an active site mutant of abrin A chain (R167L) which exhibits lower protein synthesis inhibitory activity than the wild type abrin A chain. Recombinant wild type and mutant abrin A chains were expressed in E.coli and purified. Since, abrin A chain requires the B chain for internalization into cells, both wild type and mutant abrin A chains were conjugated to native ricin B chain to generate a hybrid toxin. Next, we have compared the toxic effects of the two conjugates in cells. The rate of inhibition of protein synthesis mediated by the mutant ricin B-rABRA (R167L) conjugate was slower than that of the wild type ricin B-rABRA conjugate but it could trigger ER stress leading to mitochondrial mediated apoptosis in cells though delayed, suggesting that inhibition of protein synthesis is the major factor contributing to abrin-mediated apoptosis. Abrin is extremely lethal and considered as a potential agent for use in biological warfare. Currently, there are no antidotes or effective therapies available for abrin poisoning. Antibody based antitoxins function by either preventing toxin binding to cell surface receptors or by translocation. Antibodies against the B chain of RIPs function by inhibiting the binding of B chain of the toxin to cells, whereas the exact mechanism by which antibodies against A chain function is still not clear. The only known neutralizing monoclonal antibody against abrin A chain, namely, D6F10, was generated in our laboratory and was shown to rescue cells and mice from abrin intoxication. Earlier experiments with confocal microscopy suggested that mAb D6F10 could internalize in HeLa cells along with abrin, suggesting that the antibody can function intracellularly. Chapter 4 discusses the work carried out to delineate the mechanism of intracellular neutralization of abrin by the mAb D6F10. We observed significant reduction in binding and delay in abrin internalization in the presence of the neutralizing monoclonal antibody (mAb) D6F10. Considering that the majority of the abrin after internalization is removed by lysosomal degradation, we studied the fate of abrin in the presence of mAb D6F10. Confocal images did not show any difference in the distribution of abrin in the lysosomes in the absence or presence of antibody. However, the antibody remained persistently colocalized with abrin in the cells, suggesting that the antibody might inhibit enzymatic activity of abrin at its cellular site of action.

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46

peng, Hui-Hsuan, and 彭惠鉉. "Evaluation of cytotoxicity, mutagenicity and antimutagenicity of nine non-traditionally edible plants." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/35828413540347641141.

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碩士
國立中興大學
食品科學系
85
The Ames test was used to evaluate the toxic, mutagenic, and antimutagenic effects from edible parts of nine non- traditionally edible plants, including Crassocephalum creidioides S. Moore (Cra), Sechium americanum Poir (Sec), Portulaca oleracea L. (Por), Boussingaultia gracilis Miers var. (Bou), Corchorus capsularis L. (Cor), Centella asiatica L. Urban (Cen), Solanum nigrum L. (Sol), Basella rubra L. (Bas), and Anisogonium esculentum Presl (Ani). Comet assay was further used to evaluate the genotoxic effect of the plant extract with cytotoxic effect. Only green fruit of Sol in the absence of S9 mix showed toxicity to TA100 and Chinese hamster ovary cell (CHO) with dose-dependence. For TA100, viability were 75, 36 and 42% corresponding to the dose of 1, 3 and 5 mg/plate of green fruit of Sol, respectively; For CHO cell, cell viability was 93.7, 91.1, 91.3, 90.1, 82.8, 39.5, 5.4 and 0.9% respect to the dose of 0, 20, 40, 80, 100, 200, 300 and 400 mg/ml, respectively. Also it did not induce DNA damge within the dose range of 0-80 mg/ml.The antimutagenic potencies of the water extracts of the same nine plants against the mutagenicity of 2-amino-3-methyl[4,5-f]quinine (IQ), benzo[a]pyrene (B[a]P), and 4-nitroquinoline-N-oxide (NQNO) to TA98 and TA100 were investigated. For IQ in TA98, Sec and Sol exhibited strong antimutagenic activity; Cra, Cor, Bas, and Ani exhibited moderate antimutagenic activity; Por, Bou, and Cen exhibited weak antimutagenic activity. For IQ in TA100, Sec and Sol exhibited strong antimutagenic activity; Cra, Bou, and Cor exhibited moderate antimutagenic activity; Por, Cen, Bas, and Ani exhibited weak antimutagenic activity. For B[a]P in TA98, Cra and Sec exhibited moderate antimutagenic activity; Cen exhibited weak antimutagenic activity; whereas Cor, Bas, and Ani showed no antimutagenicity, and Por, Bou, and Sol had marginal or no antimugenic activities. For B[a]P in TA100, Cra and Sol exhibited moderate antimutagenic activity; Por, Cor, and Ani exhibited weak antimutagenic activity; whereas Sec and Cen showed no effect, and Bou and Bas had marginal effect. All samples exhibited no inhibitory effect on mutagenicity of NQNO to TA98 and TA100, except the Sol showed strong antimutagenicity to NQNO in TA100. Moreover, the mutagenicity of NQNO toward TA100 was enhanced by Sec, Por, Bou, Cen, Bas, and Ani. The antimutagenic activity of water extracts of Sec reduced after heated at 100蚓 for 20 min. And we also found that heat-stable antimutagens were produced in the plant extract preparation process (homogenized, centrifuged, and freeze-dried). The water extract of Sec was preliminary fractionated with Amicon membrane filter. Fraction with molecular weight above 30000 showed strongest antimutagenic acticity for Sec. Sec contained both heat-labile and heat-stable antimutagens. The nature of the antimutagenic components was further evaluated and compared with their antimutagenic activity. The results suggest that peroxidase is the major antimutagenic component in Sec. In addition, polyphenols is one of the heat-stable antimutagens.Key words: non-traditionally edible plants, mutagenicity, antimutagenicity, toxicity, fractionation.

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47

Tshikalange, T. E. (Thilivhali Emmanuel). "In vitro anti-HIV-1 properties of ethnobotanically selected South African plants used in the treatment of sexually transmitted diseases." Thesis, 2008. http://hdl.handle.net/2263/26030.

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48

Yang, Mei-Hsin, and 楊美欣. "Analysis and Study on the Free Radical Scavenging and Cytotoxicity of Human Breast Cancer Tumor Cell Lines for the Methanol Extracts of Coastal Plants." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/9aab9n.

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碩士
國立虎尾科技大學
生物科技研究所
100
The coastal plants refer to the plants growing in the coastal areas. Due to the harsh climate and geographical environments, the coastal plants developed various forms of special construction and physiological mechanisms to adapt to the environment, including the complicated colorful patterns, wind preventive, drought resistant, and salt tolerant features. The aim of this study is to investigate the coastal medicinal plants in Taiwan for the development of medicines and preservation of the plant resources. After the practical investigation, plant materials collection, and voucher specimen identification, totally 26 families, 43 genera, and 45 species were identified and subjected into the extraction with methanol. The methanol extracts were examined for their DPPH free radical and superoxide anion scavenging activity to evaluate the antioxidant potentials and the cytotoxicity against the human breast cancer cell lines. Among the tested, several extracts displayed significant antioxidant and cytotoxic bioactivities and were valuable to study the constituents in the future.

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49

Mboweni, Hlayisa Fredah. "Antimicrobial, cytotoxic and prelimenary phytochemical analysis of four medicinal plants and their formulation." Diss., 2018. http://hdl.handle.net/11602/1096.

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MSc (Microbiology)
Department of Microbiology
BACKGROUND: Medicinal plants form an important part of the Southern African cultural heritage. Indigenous populations, for example the Vha-Venda people, tend to use medicinal plants in formulations rather than western medicines for health and survival. In order to certify and give scientific credibility to the use of medicinal plants formulations used by Vha-Venda people for the treatment of diseases, several assays were carried out. The present study was aimed at assessing phytochemical content, antimicrobial, antioxidant and cytotoxic activities of four indigenous Venda medicinal plants in a formulation and compare their activity with each plant used individually. METHODS: Peltophorum africanum (roots), Pterocarpus angolensis (bark), Terminalia sericea (roots) and Ximenia caffra (roots) were collected from the Thohoyandou area. The collected plant parts were extracted with methanol and water respectively. Individual plant extracts and Five designed formulations were tested for their antimicrobial activity against Staphylococcus aureus ATCC 25923 (Methicillin Resistant), Staphylococcus aureus ATCC 33591(Methicillin Susceptible), beta lactamase producing Klebsiella pneumonia (ATCC 700603) and extended spectrum beta lactamase producing E. coli (ATCC 35218), four clinical isolates of Candida spp and Cryptococcus neoformans using the Broth dilution method. Minimum bactericidal concentration (MBC) of the extracts was determined by culturing the contents of minimum inhibitory concentration (MIC) on nutrient agar. Similarly, minimum fungicidal concentration (MFC) was also determined by culturing contents of MIC in sabouraud dextrose agar (SDA). Extracts were further assessed for their total phenolic content, total flavonoid content and Qualitative phytochemical analysis. The antioxidant ability of the plants extracts and formulations to scavenge free radical DPPH was also determined. The plant formulations were assessed for their anti-HIV activity using the reverse transcriptase colorimetric assay kit. Cytotoxicity against human lymphatic endothelial cells (HLEC) was determined using MTT assay. RESULTS: Methanolic and aqueous extracts of T. sericea exhibited the best antifungal and antibacterial activities whilst P. angolensis and X. caffra showed poor activities. Methanolic plant formulations showed good activities compared to aqueous formulations. However, Fractional Inhibition Concentration Index showed that there was 1 synergistic interaction, 25 additive interactions and 14 antagonistic interactions between the plant extracts. The methanolic formulation 3 showed the best overall phenolic content at 11.85±0.109 mgGAE/g whilst aqueous X. caffra extract showed the least content at 4.546±0.104 mgGAE/g. Higher total flavonoid contents were seen in methanolic formulation 4 at 2.75±0.02 mgQE/g. Qualitative phytochemical analysis revealed the presence of flavonoids, phenolics, terpenoids, tannins, saponins and steroids in 80% of the tested plant extracts and formulations. All plant extracts and formulations exhibited good antioxidant activity against DPPH. The methanolic formulation showed the best antioxidant activity with IC50 of 0.094 ± 0.33μg/ml. For anti- HIV inhibition, all formulations at 200μg/ml exhibited higher percentage of HIV-1 reverse transcriptase inhibition with methanolic mixture 3 being the best overall at 97.5% activity whilst aqueous mixture5 was the least active with 63.03% inhibition activity. Moreover, the best anti-HIV activity at 100μg/ml was exhibited by methanolic mixture 3 at 71% inhibition. Furthermore, aqueous X. caffra, mixture 2 inhibited 26% and 51% at 12.5mg/ml and 3.125mg/ml respectively. Peltophorum africanum and mixture 5 inhibited 34%, 54% and 43% at 3.125mg/ml, 6.25mg/ml and 12.5 mg/ml respectively of Human Lymphatic Endothelial cells growth. CONCLUSIONS: The results from the study indicated that most of the commonly used traditional medicinal Plants in the Venda region when mixed together have merit for use in traditional medical practice as they have shown good antimicrobial activities, good antioxidant xviii activities, good phytochemical activities and good cell proliferation activity. However some formulations showed antagonistic interaction against bacteria. Some Individual medicinal plants showed toxicity at higher concentrations against immune cells. Whereas formulations promoted cell proliferation, therefore, the use of such individual plants in the treatment of infections should be highly monitored as they may pose a health threat to normal immune cells. Generally, plants are potential pharmacological agents which needs to be preserved and harvested with care.
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Chowdhury, Abu Khayer Md Muktadirul Bari. "Composting of agro-industrial wastes." Thesis, 2014. http://hdl.handle.net/10889/8573.

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The olive oil extraction industry represents a substantial share of the economies of Mediterranean countries but leads to serious environmental problems by producing huge amounts of wastes (by-products) within a short production period. The production rate of olive oil is about 1.4-1.8 million tonnes per year in the Mediterranean, resulting in 30 million m3 of by-products and 20 million tonnes of olive pomace. A small portion of these wastes can be used as raw materials in different industries as they contain valuable natural resources. Greece has about 2300 small-scale, rural, agro-industrial units that extract olive oil. These are generally three-phase systems and their by-products include olive mill residual solids (olive pomace and leaves) and olive mill waste water. Olive mills produce significant quantities of solid wastes with outputs of 0.35 tonnes of olive pomace and 0.05 tonnes of leaves per tonne of olives. The huge quantities of olive pomace and olive leaves produced within the short oil extraction season cause serious management problems in terms of volume and space. The solid wastes (olive pomace and olive leaves) that are produced contain almost 95% organic matter and although they could be highly beneficial to agricultural soils, it has been shown that they also contain toxic compounds and lipid which increase soil hydrophobicity and decrease water retention and infiltration rate. The soils of most Mediterranean countries have low organic matter contents (<1%) which has negative impacts on agriculture. Frequent application of composted organic residues increases soil fertility, mainly by improving aggregate stability and decreasing soil bulk density. Organic amendments play a positive role in climate change abatement by soil carbon sequestration. Recurrent use of composted materials enhances soil organic nitrogen content by up to 90%. To replenish soil organic matter content and promote eco-friendly crop production, the application of olive pomace compost could be a good solution. To examine olive mill solid waste composting, four pilot-scale experiments were carried out to produce good quality compost using three phase olive mill solid waste (olive pomace, OP) and different bulking agents such as rice husk (RH), olive leaves (OL) sawdust (SD), wood shavings (WS), and chromium treated reed plants (RP). A series of parallel experiments was carried out to examine the effect final compost quality of: (a) initial moisture content, (b) water addition during the composting process, and (c) material ratios, and to also determine the toxicity level in plants and human blood lymphocytes (genotoxicity and cytotoxicity). For each experiment, six trapezoidal bins were used with dimensions 1.26 m long, 0.68 m wide and 0.73 m deep, and a total volume of 0.62 m3. The study was carried out in the facilities of the Department of Environmental and Natural Resources Management, University of Patras, Agrinio, in a closed area to maintain controlled temperature conditions. To monitor the composting process and evaluate compost quality, physicochemical parameters (temperature, moisture content, pH, electrical conductivity, organic matter, volatile solids, total organic carbon, total nitrogen, total phosphorus, potassium, sodium, and water soluble phenols) were measured at different phases. The respirometric test (O2 uptake) was performed to determine compost stability. Experimental results showed that even after short composting periods, the quality of the final product remained high. The final product had excellent physicochemical characteristics (C/N: 12.1–17.5, germination index (GI): 88.32–164.43%, Cr: 8–10 mg/kg dry mass, that fulfill1 EU requirements and can be used as a fertilizer in organic farming. To achieve higher quality of the final product, Olive pomace should be used in higher ratios than the other materials (OL, RH, WS, SD and RP). The amount (volume of humidifying agents) and time (frequency) of moisture addition also played an important role during composting. Based on the experimental results, olive mill wastes can produce a high quality soil amendment which has no phytotoxic, genotoxic or cytotoxic effects. Nevertheless, composting duration and bulking agents and their ratios are crucial factors that determine the quality of the final product. Finally, the revision of EU regulations is proposed to include genotoxic and cytotoxic evaluation of composts that enter the human food chain. A full-scale compost unit was designed based on the experimental results. For a typical small-sized olive mill, processing 30 tonnes of olives per day for a 100-day operation period, a total area of about 850 m2 is needed to compost the mill’s entire annual waste production.
Η βιομηχανία παραγωγής ελαιόλαδου αποτελεί ένα σημαντικό κομμάτι της οικονομίας στις χώρες της Μεσογείου, προκαλώντας ταυτόχρονα σημαντικά περιβαλλοντικά προβλήματα, λόγω της παραγωγής μεγάλων ποσοτήτων αποβλήτων κατά τη σύντομη περίοδο λειτουργίας των ελαιοτριβείων. Η μέση ετήσια παραγωγή ελαιολάδου στην Μεσόγειο κυμαίνεται στους 1.4-1.8 χιλιάδες τόνους, ενώ παράγονται επίσης περίπου 30 χιλιάδες m3 παραπροϊόντων και 20 χιλιάδες τόνους ελαιοπυρήνα. Μόνο ένα μικρό μέρος αυτών των παραπροϊόντων μπορεί να χρησιμοποιηθεί ως πρώτη ύλη σε διάφορες βιομηχανίες. Η Ελλάδα έχει περίπου 2300 ελαιοτριβεία μικρής κλίμακας διασπαρμένα στην ύπαιθρο. Τα ελαιοτριβεία αυτά είναι κυρίως τριφασικά και τα παραπροϊόντα τους συμπεριλαμβάνουν στερεά υπολείμματα (ελαιουρήνας και φύλλα) και υγρά απόβλητα ελαιοτριβείου. Τα ελαιοτριβεία παράγουν σημαντικές ποσότητες στερεών υπολειμμάτων παρέχοντας περίπου 0.35 τόνους ελαιοπυρήνα και 0.05 τόνους φύλλων ανά τόνο ελαιοκάρπου, παρακαλώντας σημαντικά προβλήματα στη διαχείρισης τους. Τα στερεά υπολείμματα (ελαιοπυρήνας και φύλλα) περιέχουν 95% οργανική ύλη, καθιστώντας τα δυνητικά κατάλληλα ως εδαφοβελτιωτικά, καθώς τα εδάφη των περισσότερων Μεσογειακών χωρών έχουν χαμηλή περιεκτικότητα σε οργανική ύλη (<1%) επηρεάζοντας αρνητικά την γεωργία. Τα υπολλείματα αυτά περιέχουν ωστόσο τοξικές ουσίες και έλαια, τα οποία αυξάνουν την υδροφοβικότητα του εδάφους και μειώνουν την κατακράτηση του νερού και την ρυθμό διήθησης. Έχει αποδειχθεί ότι συχνές εφαρμογές κομποστοποιημένων οργανικών υπολειμμάτων αυξάνουν την γονιμότητα του εδάφους, αυξάνοντας κυρίως τη συνολική σταθερότητα και την πυκνότητα του εδάφους. Η συχνή χρήση κομποστοποιημένων υλικών βελτιώνει την περιεκτικότητα των εδαφών σε οργανικό άζωτο του εδάφους έως και 90%. Η κομποστοποίηση ελαιοπυρήνα θα μπορούσε να αποτελέσει μια πιθανή λύση για την αναπλήρωση του περιεχομένου σε οργανική υλη των εδαφών και για την προώθηση μιας οίκοφιλικής αγροτικής παραγωγής. Για να εξεταστεί η κομποστοποιήση στερεών υπολειμμάτων ελαιοτριβείων, διεξήχθησαν 4 πειράματα πιλοτικής κλίμακας για την παραγωγή κομποστ, χρησιμοποιώντας στερεά υπολείμματα τριφασικών ελαιοτριβείων (ελαιοπυρήνας) και διαφόρους διογκωτικούς παράγοντες, όπως φλοιό ρυζιού, φύλλα ελιάς, πριονίδια, ροκανίδια, και καλάμια με υψηλή περιεκτικότητα σε χρώμιο. Σκοπός των παράλληλων πειραμάτων ήταν η εξέταση της επίδρασης στην ποιότητα του τελικού κομπόστ των: (α) αρχικού περιεχόμενου υγρασίας, (β) της προσθήκης νερού κατά την διάρκεια της κομποστοποιήσης, (γ) των ποσοστών ανάμιξης των υλικών, καθώς επίσης και ο προσδιορισμός της φυτοτοξικότητας και της γενοτοξικότητας των τελικών κομπόστ. Σε κάθε πείραμα χρησιμοποιήθηκαν 6 τραπεζοειδή πλαστικά δοχεία διαστάσεων 1.26 m σε μήκος, 0.68 m σε πλάτος και 0.73 m σε ύψος, με ολικό όγκο 0.62 m3. Οι πιλοτικές μονάδες ήταν τοποθετημένες σε κλειστό χώρο του Τμήματος Διαχείρισης Περιβάλλοντος και Φυσικών Πόρων του Πανεπιστημίου Πατρών στο Αγρίνιο, ώστε να επικρατούν σταθερές συνθήκες θερμοκρασίας. Η παρακολούθηση της κομποστοποίησης και η εκτίμηση της ποιότητας του κομπόστ, έγινε μέσω του προσδιορισμού διαφόρων φυσικοχημικών παραμέτρων (θερμοκρασία, περιεχόμενο υγρασίας, pH, ηλεκτρική αγωγιμότητα, περιεχόμενη οργανική ύλη, πτητικά στέρεα, ολικός οργανικός άνθρακας, ολικό άζωτο, ολικό φώσφορος, κάλιο, νάτριο, και ολικές φαινόλες). Για την εκτίμηση της ποιότητας του κομποστ πραγματοποιήθηκαν επίσης ρεσπιρομετρικά τεστ (κατανάλωση O2). Τα πειραματικά αποτελέσματα απέδειξαν ότι ακόμα και μετά από σύντομες περιόδους κομποστοποιήσης η ποιότητα του τελικού κομπόστ παρέμενε υψηλή. Το τελικό προϊόν είχε εξαιρετικά φυσικοχημικά χαρακτηριστικά (C/N: 12.1–17.5, δείκτης βλαστικότητας (GI): 88.32–164.43%, Cr: 8–10 mg/kg ξηρής μάζας), τα οποία είναι εντός των νομοθετικών ορίων της ΕΕ για την χρήση λιπασμάτων σε βιολογικές καλλιέργειες. Για την παραγωγή υψηλής ποιότητας κομπόστ ο ελαιοπυρήνας πρέπει να χρησιμοποιείτε σε μεγαλύτερη αναλόγια σε σχέση με τα υπόλοιπα υλικά. Η ποσότητα και η συχνότητα προσθήκης νερού παίζει επίσης σημαντικό ρόλο κατά τη κομοστοποιήση. Με βάση τα πειραματικά αποτελέσματα αποδείχθηκε ότι τα στερεά υπολείμματα ελαιοτριβείων μπορούν να παράξουν ένα υψηλής ποιότητας εδαφοβελτιωτικό, το οποίο δεν εμφανίζει φυτοτοξικότητα, γενοτοξικότητα και κυτταροτοξικότητα. Παρόλο αυτά η διάρκεια της κομποστοποίησης, οι διογκωτικοί παράγοντες και τα ποσοστά ανάμιξης των υλικών είναι κρίσιμοι παράγοντες, που επηρεάζουν την ποιότητα του τελικού προϊόντος. Επίσης αναφέρουμε ότι η νομοθεσία της ΕΕ θα πρέπει να αναθεωρηθεί συμπεριλαμβάνοντας τόσο τη γενοτοξική και την κυτταρτοξική εκτίμηση του κομπόστ πριν χρησιμοποιηθεί για βρώσιμες καλλιέργειες. Τέλος με βάση τα πειραματικά αποτελέσματα διαστασιολοήθηκε μια μονάδα πλήρους κλίμακας για την κομποστοποίηση στερεών υπολειμμάτων ελαιοτριβείου. Έτσι για ένα τυπικό μικρής κλίμακας ελαιοτριβείο, που επεξεργάζεται ημερησίως 30 τόνους ελιών και για περίοδο κομποστοποίησης 100 ημερών, χρειάζεται μια συνολική έκταση περίπου 850 m2 για τη κομπστοποίηση όλης της ετησίας ποσότητας του ελαιοπυρήνα.

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