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1
Swartz, Vuyiswa Gladys. "Phytochemical studies of Helichrysum patulum." Thesis, University of the Western Cape, 2006. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_3651_1189147447.
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Since Helichrysum is known by the indigenous people of Africa for therapeutic properties, such as against colds, flu and wounds, the aim of this study was to focus on the patulum species found predominantly in the Western Cape region of South Africa and by means of isolation and identification of the plant constituents, be able to relate the therapeutic activity on the basis of literature precedents, to the compounds extracted.
2
Nqolo, Nandipha Lucia. "Phytochemical study of Rhoicissus tomentosa." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_3223_1263940394.
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This investigation focused on Rhoicissus tomentosa, belonging to the family, Vitaceae in an attempt to assess the phytochemistry of this plant which is widely used by traditional healers in South Africa to ensure the safe delivery during pregnancy and childbirth (Hutchings et al., 1996).
3
Latip, Jalifah. "Phytochemical studies on Australian Rutaceae." Thesis, University of Strathclyde, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366989.
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Seneviratne, G. Idrani. "Phytochemical survey of cultivated Vigna species." Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314782.
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Shaari, Khozirah. "Phytochemical studies on the Malaysian Flacourtiaceae." Thesis, University of Strathclyde, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296099.
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6
Zhou, Kequan. "Phytochemical profiles and antioxidant properties of wheat." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2729.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2005.Thesis research directed by: Food Science. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
7
Araim, Ghada. "Phytochemical induction in Echinacea purpurea (L) Moench." Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27440.
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Purple coneflower, Echinacea purpurea (L.) Moench, is an important phytomedicinal species, producing phenolics and alkamides which have medicinal properties. This study examined the contribution of arbuscular mycorrhizal (AM) colonization on the physiology and biochemistry of E. purpurea, alone or in combination with jasmonic acid (JA), and over time. It was hypothesized that AM colonization enhances growth, nitrogen assimilation and secondary metabolism in E. purpurea. It was also hypothesized that JA application alone, or in combination with AM colonization, and growth time increases the phytochemical content. To verify these hypotheses, three greenhouse experiments were performed with E. purpurea, with or without AM fungus, Glomus intraradices Schenck & Smith, and harvested after (1) 13 weeks of growth; (2) 13 weeks and JA treatment; and (3) five different growth periods starting from week four to fifteen. The overall results indicated that AM colonization significantly increased the mass of shoots and roots, the concentration of proteins in roots and most of the phenolics. Results also suggested that the effects of AM colonization and/or JA application are similar on the induction of phenolics. Furthermore, time was a main factor on the enhancement of the phytochemical content, of the alkamides found to be dominant in roots, and phenolics in shoots. Optimizing the growth by AM colonization represents an organic method of enhancing E. purpurea yield and phytochemical content.
8
Mwangi, Henry Maina. "Phytochemical and antimicrobial studies on Rhus natalensis." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_3552_1365671232.
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Extracts from the root bark, stem bark, and leaves of R. natalensis were screened for antibacterial activity against standard bacterial strains
Staphylococcus aureas, Escherichia coli and Pseudomonas aureginosa, and fungi
Candida albicans, Trichophyton mentagrophytes or Microsporum gyseum. Chromatographic techniques were utilized to isolate pure compounds. This study validates and documents, in a systematic way, the antimicrobial properties of the R. natalensis used for many years by many people of the world. It also provides valuable information for
further phytochemical isolation and characterization studies of active compounds, necessary for the development of new drugs. The extractions were carried out using broad spectrum of solvents
(hexane, dichloromethane, ethyl acetate, and methanol). Fractionation was done using standard chromatographic techniques. A total of seven (7) compounds were isolated from R. natalensis.
Three of the isolates were characterized and their structures were unambiguously established by detailed spectroscopic analysis that involved high resolution mass spectrometry, 1D and
2D-NMR spectral data experiments 1H, 13C, DEPT, COSY, HMBC, and NOESY. These compounds are: 3-(1-(2,4-dihydroxyphenyl)-3,3-bis(4- hydroxyphenyl)-1-oxopropan-2-yl)-7-methoxy- 4H-chromone-4-one (39), Rhuschromone, a
novel compound isolated for the first time, 2&rsquo
,4&rsquo
-dihydroxychalcone-(4-O-5&rsquo
&rsquo
&rsquo
)-4&rsquo
&rsquo
,2&rsquo
&rsquo
&rsquo
,4&rsquo
&rsquo
&rsquo
- trihydroxychalcone (40) and 3-((Z)-heptadec-13-enyl) benzene- 1,2-diol (41), an urushiol. Compound 39 recorded the highest activity zone of inhibition (21mm) against S. aureas, which was found to be 50% as active the chloramphenicol standard used. The
traditional use of the extracts in infections and inflammatory conditions is rationalized based on the content of theisolated compounds, and it has been proposed that the total crude extract, with its
contents of so many bioactive compounds, could be formulated for use in many infections, microbial or fungal. Furthermore, not all of the species studied to date have been fully characterized
for potential bioactivities. Thus, there remains a significant research gap spanning the range from lead chemical discovery through process development and optimization in order to better
understand the full bioactive potential of many of these plants.
9
Brown, Paula Naomi. "Cranberry metabolomics : new approaches for phytochemical characterizations." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/39867.
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There is a long history of use and modern commercial importance of large (Vaccinium macrocarpon Aiton) and small cranberries (V. oxycoccus L. and V. vitis-idaea L.) in North America. While epidemiological research indicates cranberries have positive health benefits, identifying specific phytochemicals for disease prevention remains elusive. The central objective of this research was to develop phytochemical characterization tools for comparing commercially cultivated cranberries and two wild-harvested Vaccinium species. A method was developed and validated to quantify cyanidin-3-O-galactoside (C3Ga), cyanidin-3-O-glucoside (C3Gl), cyanidin-3-O-arabinoside (C3Ar), peonidin-3-O-galactoside (P3Ga) and peonidin-3-O-arabinoside (P3Ar) in cranberry fruit products. The relative standard deviation (%RSDr) of anthocyanins ranged from 1.77% to 3.31% with the method detection limit (MDL) for C3Ga, C3Gl, C3Ar, P3Ga, and P3Ar estimated at 0.018, 0.016, 0.006, 0.013, and 0.011 µg/mL, respectively. In biological replicates of V. macrocarpon cultivars, anthocyanin content (mg/g) was determined to be 7.98±5.83 in Ben Lear; 7.02±1.75 in Bergman; 6.05± 2.51 in GH1; 3.28± 1.88 in Pilgrim and 2.81 ±0.81 in Stevens. V. oxycoccus contained the five major anthocyanins with the ratio of glycosylated peonidins to cyanidins varying from V. macrocarpon. V. vitis-idaea contained no measurable glycosylated peonidins. Determination and statistical analysis of serotonin, melatonin and ascorbic acid content in the three Vaccinium species, found only vitamin C positively correlated with antioxidant activity. Metabolome comparisons made from untargeted metabolomics by ultra-fast liquid chromatography (UFLC) with time-of-flight (TOF) mass spectrometry (MS), found different pools of common metabolites extracted in methanol (7635), 70% ethanol (5832), and water (5664). Each cranberry matrix contained unique compounds; fruit=3680, product 1=3464, product 2=3500. Clustering was visualized using principal component and partial least squares discriminate analyses with application of univariate statistics to mitigate false discoveries. A significance algorithm found 1987, 716 and 1556 compounds (p-value<0.05) in methanol, 70% ethanol and water extracts, respectively. In metabolomic profiles of V. macrocarpon varietals 6481 compounds were conserved and 136 (Ben Lear), 84 (Bergman), 91 (GH1), 128 (Pilgrim) and 165 (Stevens) unique observations were made. Across the three Vaccinium species 8000-10,000 phytochemicals were detected with 4624 compounds conserved between them. Together these data establish targeted and untargeted methods for phytochemical characterization of cranberries, providing foundational chemotaxonomic knowledge and new insights into the maintenance of health in traditional North American diets.
10
Singh, Sumitra. "Phytochemical and biological studies on Asian plants." Thesis, University of Strathclyde, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249201.
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Khan, M. R. "Phytochemical study of some Costa Rican plants." Thesis, University of Strathclyde, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381696.
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Katerere, David R. P. "Phytochemical and pharmocological investigations of African Combretaceae." Thesis, University of Strathclyde, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249017.
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Rashid, Md Abdur. "Phytochemical and chemosystematic studies in Eriostemoninae (Rutaceae)." Thesis, University of Strathclyde, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296095.
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Guntupalli, Chakravarthi. "Phytochemical and biological investigations of rutaceous plants." Thesis, University of Sunderland, 2008. http://sure.sunderland.ac.uk/3685/.
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The Rutaceae family consists of 150 genera and 1,500 species, which are herbs, shrubs, and trees. The members of genus Glycosmis and Clausena are aromatic (contain volatile oils) and traditionally used for fever, swollen spleen, digestion, topical infections, skin itch, scabies, boils and ulcers. Accordingly from this family, Tetractomia roxburghiana, Glycosmis calcicola, and Clausena excavata were selected for systematic biological screening to exploit and identify compounds which may serve as subsequent leads for the treatment of skin diseases. While the initial aim of the programme had been to characterise these barely studied plants, the programme was subsequently extended to study their biological activity in order to justify their traditional use as medicines. During the course of this study, supporting analytical methodologies were used extensively and ultimately the evaluation of these methodologies contributed a significant proportion of the overall research programme. Initially crude extract was subjected to column chromatography and the compounds were isolated by overloading an analytical HPLC column. By the end of the programme, crude extracts were being analysed directly by gradient reversed-phase HPLC with subsequent direct scale up to preparative isolation on a (250 ´ 22) mm id column. Analytical reversed phase high performance liquid chromatography (HPLC) of the crude methanolic leaf extracts of T. roxbhurghina, G. calcicola, and C. excavata was carried out in order to qualitatively assess the number of constituents present in each fraction. Separation was achieved by using ACE-5-C18 (250 ´ 4.6 mm) with a flow rate of 1.5 ml/min, with the UV detection at 254 nm. Semi-preparative and preparative HPLC were also carried out in order to isolate components of these mixtures. Using spectral analysis, as swertisin, gallic acid, α-asarone and angelicin (furanocoumarin) were identified. In the same way, angelicin was identified from the methanolic leaf extract of Glycosmis calcicola and preparative HPLC of the methanolic leaf extract of Clausena excavata afforded three compounds, namely 2-(3,4-dimethoxy-phenyl)-5,7-dimethoxy-chromen-4-one, 2-(3,4-dimthoxy-phenyl) 3,7-dihydroxy-5-methoxy-chromen-4-one and 5,7-dihydroxy-2-phenyl-chromen-4-one (chrysin), which were confirmed by spectroscopic methods. Micellar electrokinetic chromatography (MEKC) was evaluated as a possible high-resolution technique for checking the purity of fractions isolated from preparative RP-HPLC. However it proved more effective to exploit orthogonal ( to RP-HPLC) modes of LC by using –NH2 and –SCX ion-exchange HPLC columns and/or, if resolution on analytical RP-HPLC was possible, structural elucidation was carried out using LC-NMR-MS. With respect to biological activity, a range of procedures that had been established at the University for checking activity against skin diseases was used. Free radical induced lipid peroxidation model has been selected for evaluation of antioxidant activity of the extract. The anti-oxidant activity of these extracts and compounds were assessed by free radical induced lipid peroxidation model. The results indicated that the methanolic leaf extract of Tetractomia roxburghiana showed marked anti-oxidant activity whereas methanolic leaf extract of Glycosmis calcicola and Clausena excavata showed moderate anti-oxidant activity. The IC50 value of the methanolic leaf extract of Tetractomia roxburghiana was found to be 201.3 µg/ml; whereas those for Glycosmis calcicola and Clausena excavata were found to be 450.6 µg/ml and 1106 µg/ml respectively. For all the extracts, no anti-bacterial activity was found against Staphylococcus aureus, Streptococcus pyogenes, Propionibacterium acne. Also no anti-fungal activity against Candida albicans was found. A total of three crude methanolic plant extracts, four isolated compounds and eleven semi-purified fractions were tested for in-vitro efficacy, using an agar incorporation method to determine the minimum inhibition concentration (MIC), against the dermatophyte species; Trichophyton rubrum, Trichophyton mentagrophytes and Epidermatophyton floccusum. The MIC value for crude methanolic extracts of Tetractomia roxbhurghiana and Glycosmis calcicola was found to be 62.5 µg/ml and 31.2 µg/ml against T.rubrum and T.mentagrophytes, whereas the methanol extract of Clausena excavata did not show any activity against dermatophytes. In conclusion, the anti-oxidant activity of Tetractomia roxburghiana was found to be comparable with that of propylgallate, which was used as a standard drug thus confirming, as anticipated, that Tetractomia roxburghiana might be a good source of anti-oxidant drugs. The extended degree of anti-oxidant activity displayed by methanolic extract of Tetractomia roxburghiana could be contributed to the presence of swertisin, gallic acid and angelicin, which are proven anti-oxidants. The anti-fungal activity of Glycosmis calcicola could be partly due to the presence of angelicin.
15
Silva, Francisco Josà Souza da. "Phytochemical study of Croton Jacobinensis Baill (Euphorbiaceae)." Universidade Federal do CearÃ, 2010. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6540.
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CoordenaÃÃo de AperfeiÃoamento de NÃvel SuperiorEuphorbiaceae is a family of plants that have more than 8000 species with over 300 genera, widely distributed in tropical and temperate regions worldwide. Despite the wide distribution of this family, many species have never been studied in the chemical point of view. One of these species is Croton jacobinensis, restricted to Brazilian semi-arid region, known popularly as marmeleiro-branco. To contribute to the chemical knowledge of this species the woody of the roots of this plant was subjected to a cold extraction with a mixture of dichloromethane / methanol (2:3). The extract obtained after liquid-liquid extraction and concentration was subjected to successive chromatographic treatments on silica gel resulted in isolation and characterization of the mixture of steroid β-sitosterol and stigmasterol, and three diterpenes, two of the basic skeleton of the class crotofolano, one of them being registered as crotofolina E and the other character unpublished. The other diterpene isolated belong to the class of labdane and is also unprecedented in the literature. For the isolation of secondary metabolites usual chromatographic techniques were employed as thin layer chromatography, filtration chromatography and flash chromatography. Structure determination of non-volatile constituents was achieved by the use of techniques: Infrared (IR), mass spectrometry (MS) and Nuclear Magnetic Resonance of Hydrogen-1 and Carbon-13 (1H and 13C NMR uni and bidimensional) and comparison with literature data.
Euphorbiaceae à uma famÃlia de plantas que possui mais de 8 mil espÃcies com mais de 300 gÃneros, amplamente distribuÃdas em regiÃes tropicais e temperadas de todo o mundo. Apesar da larga distribuiÃÃo desta famÃlia, muitas espÃcies nunca foram estudadas no ponto de vista quÃmico. Uma destas espÃcies à o Croton jacobinensis, restrita ao semi-Ãrido brasileiro, conhecido popularmente por marmeleiro-branco. Visando contribuir para o conhecimento quÃmico desta espÃcie, o lenho das raÃzes desta planta foi submetido a uma extraÃÃo a frio com a mistura de diclorometano/metanol (2:3). O extrato obtido apÃs extraÃÃo lÃquido-lÃquido e concentraÃÃo foi submetido a sucessivos tratamentos cromatogrÃficos em gel de sÃlica resultando no isolamento e caracterizaÃÃo da mistura dos esterÃides β-sitosterol e estigmasterol e de trÃs compostos diterpÃnicos: dois de esqueleto bÃsico da classe crotofolano, sendo um registrado como crotofolina E e o outro de carÃter inÃdito. O outro diterpeno isolado pertence à classe dos labdanos e tambÃm à inÃdito na literatura. Para o isolamento dos metabolitos secundÃrios foram empregadas tÃcnicas cromatogrÃficas usuais como cromatografia em camada delgada, cromatografia filtrante e cromatografia relÃmpago. A determinaÃÃo estrutural dos constituintes nÃo volÃteis isolados foi realizada atravÃs da utilizaÃÃo das tÃcnicas de: Infravermelho (IV), espectrometria de massa (EM) e RessonÃncia MagnÃtica Nuclear de HidrogÃnio-1 e Carbono-13 (RMN 1H e 13C uni e bidimensionais), alÃm de comparaÃÃo com dados descritos na literatura.
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Jadalla, Baraa Mohamed Ibrahim Soliman. "Phytochemical and biological studies of Helichrysum cymosum." University of the Western Cape, 2020. http://hdl.handle.net/11394/8264.
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Masters of ScienceDiabetes mellitus (DM) is well known as a group of systemic metabolic disorders with a considerable mortality rate around the world. Hyperglycemia is the main consequence of DM, which results from the shortage in insulin production or degradation of produced insulin. Other internal and external factors including obesity, oxidative stress, and sedentary lifestyle have been also suggested as the causes of DM. Among the well-known existing types of DM, type 1 and 2 are the most common. Treatment of type 1 necessitates insulin injection, while type II can be controlled by physical exercises, diet control in addition to different synthetic antidiabetic drugs. However, their effectiveness is restricted because of the high cost and unfriendly side effects. There is a significant need for producing alternative and more bioactive antidiabetic drugs from natural sources. Natural products are a well-known source for the discovery of new scaffold for drugs discovery, and South Africa is one of the most important megaflora with a high percentage of endemism. South Africa is home to about 245 species of Helichrysum species, which are generally rich sources of secondary metabolites, especially flavonoids, which give them a great value for global acceptability and wide application in the pharmaceutical fields as antibacterial, anti-inflammatory, antioxidant, and antidiabetic agents. The phytochemical investigation of the methanolic extract of H. cymosum resulted in the isolation and identification of seven pure compounds (1-7). Structural characterization of these isolated compounds was conducted using 1D NMR, in comparison with reported spectroscopic data. The in vitro bio-evaluation of H. cymosum against alpha-glucosidase shown that 5 exhibited the highest alpha-glucosidase inhibitory activity with IC50 value of 13 μM, followed by 7 and 3 with IC50 values of 18.16 μM and 44.4 μM respectively. Additionally, strong total antioxidant capacities were displayed by 6 and 2 as ORAC (122.86 ± 0.7 and 91.70 ± 0.4 μM TE/mL) respectively as well as 5 and 7 as FRAP (1006.34 ± 1.7; 977.79 ± 0.8) μM AAE/g. This is the first scientific report to be carried out on alpha-glucosidase inhibitory activities and antioxidant capacities of H. cymosum constituents. The findings suggest that these compounds might become prominent natural candidates to inhibit alpha-glucosidase as well as oxidative stress related to diabetes with the prospect to be employed in the formulation of diabetes drugs upon further biological studies.
17
Kim, Youngmok. "Factors influencing antioxidant phytochemical stability of teas." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3172.
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Wahyuono, Subagus. "PHYTOCHEMICAL INVESTIGATION OF AMSONIA GRANDIFLORA FAMILY APOCYNACEAE." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275413.
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Makhaba, Masixole. "Phytochemical studies of extracts from Aloe succotrina." University of the Western Cape, 2017. http://hdl.handle.net/11394/6457.
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Magister Scientiae - MSc (Chemistry)Global climate change and geographical differences are two major parameters known to have, either, direct or indirect influence on the production of secondary metabolites in plants, which in-turn may affect the quality and/or quantity of the overall metabolites. The primary purpose of this thesis was to evaluate the phytochemistry of the whole leaf of Aloe succotrina Lam. spp. - a South African native plant - through a chromatographic spectroscopic approach-against available data accumulated for the cultivated population. Preliminary screening of the crude extracts i.e. HEX, DCM and EtOAc on TLC aluminium plates precoated with silica gel 60 F254 followed by various chromatographic separation, led to the isolation of five known compounds: ?-sitosterol (1) and two anthrone-C-glycosides (2 and 5), including two coumarin derivatives-the aglycone (3) and glycoside derivative (4). Notably, apart from 5 and 2, the accumulation of 1, 3 and 4 in A. succotrina Lam. spp. is reported for the first time. Structural elucidation of the individual compounds was achieved by extensive spectroscopic analysis i.e. MS, IR, 1H and 13C-NMR spectroscopy and in some cases comparison to the literature. A comparative HPLC chromatogram of the crude MeOH extract of the leaves of A. succotrina Lam. was developed for qualitative (and quantitative) identification of the active metabolites, which could be realized by VWD with detection at 290 nm.
20
Usman, Abdullahi. "Phytochemical investigation of Trichilia emetica (Natal mahogany)." Thesis, Bangor University, 2015. https://research.bangor.ac.uk/portal/en/theses/phytochemical-investigation-of-trichilia-emetica-natal-mahogany(7ec79b6e-96b9-4811-a7a6-407ad97bd8e1).html.
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Trichilia emetica seeds have already been utilised for oil extraction. This project investigated the chemistry of by-products, especially water after boiling the seeds and the defatted residue. The first part of the study was to subject the seed oils to physicochemical analysis using standard methods of food analysis. The data obtained were acid (0.4±0.0 and 0.4±0.1 mg KOH/g), iodine (69.2±2.1 and 64.6±2.8 gI2/100g), peroxide (10.3±0.5 and 9.2±0.4 %) and saponifiable value (195.4±5.4 and 197.3±4.6) for T. emetica seeds from Ghana and Mozambique and were comparable to those of other edible oils. The fatty acid composition of the seeds and shell oils was determined using different analytical methods. The result obtained using 1H and 13C NMR and GC-MS of fatty acid methyl esters are 56-65% saturated (C14:0, C16:0, C18:0), 27-34% monounsaturated (C18:1, ω-9) and 4-10% polyunsaturated (C18:2 ω-6, 9 and C18:3 ω-6, 9, and 12) are in good agreement between the different methods of analysis for the proportion of individual fatty acids. Linolenic acid methyl ester was not detected in the seed oil. Phytochemical investigation of the unsaponifiable fraction of T. emetica seed oil resulted in the isolation of two sterols, β-sitosterol and stigmasterol. The second part of the study was the phytochemical examination of the boiled water extract of the seed. This resulted in the isolation of one new flavanol glycoside, catechin-3-O-α-L-rhamnopyranosyl (1→4) β-D-glucopyranoside and eight known compounds; catechin, epicatechin, taxifolin, elephantorrhizol, catechin 3-O-β-D-glucopyranoside, taxifolin 4’-O-β-D-glucopyranoside and eriodictyol 4’-O-β-D-glucopyranoside. Similarly, three known compounds Naringenin, Quercetin and Quercetin 3-O-β-D-glucopyranoside were isolated from the stem. To the best of our knowledge, this is the first report on the phenolic content of T. emetica. The third part of the study was the use of Azadirachta indica seeds and the seeds oil of Millettia pinnata as a model to check the various methods used in the unsuccessful attempt to isolate a limonoids from the seeds of T. emetica. These resulted in the isolation of two known limonoids and three furanoflavonoids: azadirachtin, nimbin, karanjin, pongapin and lanceolatin. The structures of these compounds were determined on the basis of spectroscopic methods and by comparison of the data obtained with literature. Some compounds were confirmed with X-ray crystallography.
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Freschi, Michela <1992>. "Neuroprotective role of nutraceutical and phytochemical components." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10233/1/PhD%20Thesis_Michela%20Freschi.pdf.
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Neurodegenerative diseases (NDs) are characterized by a multifactorial etiology, in which oxidative stress and inflammation are the main causative factors. For this reason, increasing attention is being paid to the characterization and the identification of nutraceuticals and phytochemicals with intrinsic pleiotropic activity. Moreover, in a Circular Economy perspective, these natural compounds can be obtained also from renewable resources derived from the food industry by-products and can be used for both preventive and therapeutic purposes.
The aim of this PhD program was to identify nutraceuticals and phytochemicals, both as extracts and pure compounds, and obtained from both plant and renewable sources, which due to their antioxidant and anti-inflammatory properties, were able to counteract cellular and molecular alterations that characterize NDs. Their neuroprotective potential has been evaluated in an in vitro model of neuroinflammation (the LPS-activated BV-2 microglial cell line), and/or in an in vitro model of neuronal oxidative stress (the neuron-like SH-SY5Y cell line differentiated with retinoic acid and exposed to H2O2).
Four different projects, although deeply linked by the aforementioned common goal, have been discussed in this thesis:
1_ Impact of phenolic profile of different cherry cultivars on the potential neuroprotective effect in SH-SY5Y cells.
2_Anti-inflammatory activities of Spilanthol-rich essential oil from Acmella oleracea (L.).
3_Study of the anti-inflammatory activity of novel tacrine derivatives with lipids extracted from cashew nutshell liquid.
4_Coffee Silverskin (CSS) and Spent Coffee Grounds (SCG): coffee industry by-products as a promising source of neuroprotective agents.
In general, it is, therefore, possible to conclude that the natural compounds studied in this thesis have been proven, due to their antioxidant and/or anti-inflammatory properties, to be valid preventive and therapeutic strategies for the treatment of NDs, to improve the life quality of these patients and of the general population by preventing and combating the onset of these deleterious diseases.
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Omar, Semir. "Phytochemical discovery of antifeedant, antimicrobial and antimalarial principles." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ66179.pdf.
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Habtemariam, Solomon. "Phytochemical and pharmacological investigation of some medicinal plants." Thesis, University of Strathclyde, 1992. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21299.
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This thesis describes phytochemical and biological/pharmacological studies on six medicinal plants. Plant materials were extracted by ethanol, tested for their biological activity and then subjected to "bioassay-guided fractionation" to yield active and inactive compounds. The compounds were identified by standard physico-chemical techniques including UV, IR, NMR and ElMS. The crude ethanol extract of the leaves of Premna shcimperi was found to be antibacterial against gram positive bacteria (Staphylococcus aureus and Bacillus subtilis). An antibacterial bioassay-guided fractionation of the extract resuited in the isolation of the active principle, (5R,8R,9S,10R)-12-oxo-ent-3,13(16)- clerodien-15-oic acid (SHM-l). This novel compound was bactericidal against S. aureus and B. subtilis at concentrations of 25 and 50 µg ml⁻¹. Studies on the structural-activity relationship of SHM-l showed that the α,β unsaturated moiety played a major role in its antibacterial activity. Investigation of the inactive fractions of P. schimperi extract afforded three flavonoid aglycones: luteolin, quercetin and kaempferidej three flavonoid glycosides: luteolin-4" -,β-D-glucoside, quercetin-3-,β-D-galactoside and quercetin-α-L-arabinopyranoside and five cinnamate and benzoate derivatives. The ethanol extract of the leaves of Premna oligotricha was also found to be antibacterial against a range of gram-positive bacteria. A bioassay-directed isolation afforded three novel active principles, two diterpenes: 16-hydroxy-clerod- 3,13(14}-diene-15,16-olide (SHM-3) and ent-12-oxolabda-8,13(16}-dien-15-oic acid (SHM-S) and a sesquiterpene, 7-α, hydroxy-2-oxo-6,11-cyclofarnes-3(15)-ene (SHM-19). While the activity of SHM-5 and SHM-19 was marginal that of SHM-3 was good, almost comparable with streptomycin. The antimicrobially inactive fractions of P. oligotricha extract yielded a novel diterpene, ent-8,β12α-epidioxy- 12,β-hydroxlabda-9(11), 13-dien-15-oic acid γ lactone and two novel flavonoids: 3,5,5'-trihydroxy-6,7 ,3' ,4'-tetramethoxyflavone and 3,5,7 ,5'-tetrahydroxy-6,3',4'- trimethoxyflavone. Investigation of the leaves of Premna recinosa afforded six flavonoids: quercetin, luteolin, pachypodol, chrysosplenol-D, naringenin and eriodictyol and three lignans: {+)-8-hydroxy-pinoresinol, {+)-lariciresinol and {-)-seco-isolariciresinol. Portulaca oleracea and Pentas schimperiana are used in the folk medicine as local anaesthetics. Studies on the isolated nerve and/or muscle preparations showed that extracts do block nerve conduction in these excitable tissues. A subsequent systematic bioassay-guided fractionation of crude extracts showed that excess potassioum ions in the extracts were responsible for the in vitro pharmacological activity of P. oleracea and P. schimperiana. Extracts from the leaves of Leonotis ocymifolia var raineriana showed no antibacterial activity. Three novel diterpenes: ent- {13S)-9,13α-epoxylabda- 6{ 19),β,16{15)-diol dilactone, (13R)-6,β-acetoxy-9, 13α-epoxylabda-19(20),8,16{ 15)- diol dilactone and 20,8-acetoxy-9α,13e-dihydroxy-15(16)-epoxy-Iabd-14-en-6,19,(β- O-lactone together with a known compound: {13S)-20,β-acetoxy-9,13α-epoxylabda- 6(19),β,16{15)-diol dilactone were isolated. Investigation of the root afforded two known compounds 3-methoxy-4-hydroxy-{trans)-cinnamaldehyde and 3-methoxy- 4-hydroxy-bezaldehyde.
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Shiu, Ka Po Winnie. "Phytochemical and Antibacterial Studies on the Genius Hypericum." Thesis, University College London (University of London), 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.499161.
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Stavri, Michael. "Phytochemical and antimicrobial studies on selected Kuwati flora." Thesis, University College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411791.
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Etse, J. T. "Phytochemical studies on some species of the Annonaceae." Thesis, University of Strathclyde, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381499.
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Sousa, LeÃncio Mesquita de. "Phytochemical study of Macroptilium lathyroides (L.) Urb. (FABACEAE)." Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6518.
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FundaÃÃo de Amparo à Pesquisa do Estado do CearÃUma das prÃticas mais antigas no tratamento e na cura das enfermidades à sem dÃvida nenhuma, o uso dos produtos naturais, especialmente, os de origem vegetal. Atà o sÃculo XIX, os recursos terapÃuticos eram predominantemente constituÃdos pela utilizaÃÃo de partes das plantas e extratos vegetais. Com o avanÃo dos instrumentos cientÃficos e tecnolÃgicos se estabeleceu a tendÃncia de utilizaÃÃo das substÃncias ativas presentes nas plantas. Realizou-se a inve stigaÃÃo fitoquÃmica dos galhos e talos e das raÃzes de Macroptilium lathyroides. Esta espÃcie està inserida na subfamÃlia Papilionoideae da famÃlia Fabaceae. Do extrato em hexano dos talos e galhos foi isolada a mistura dos esterÃides sitosterol e estigmasterol (ML-1). Do extrato em hexano das raÃzes foram isolados a lasiodiplodina (ML-2) e a mistura dos esterÃides 6β-hidroxi-estigmast-4-en-3-ona e 6 β - hidroxi-estigmast-4,22-dien-3-ona (ML-3) e do extrato em acetato de etila das raÃzes foram isolados de-O-metil-lasiodiplodina (ML-4) e 4',5,7-triidroxiisoflavona (ML-5). Os compostos isolados foram identificados atravÃs dos mÃtodos espectroscÃpicos (IV, EM, RMN 1 H e RMN 13C), incluindo tÃcnicas bidimensionais (H MBC, HSQC e COSY) e comparaÃÃo com dados da literatura. Os extratos obtidos foram avaliados quanto à atividade larvicida sobre Aedes aegypti, mostrando-se, portanto, inativos. Este à o primeiro relato do estudo fitoquÃmico de Macroptilium lathyroides, bem como da investigaÃÃo da atividade larvicida dos extratos obtidos.
One of the oldest practices in the treatment a nd cure of diseases is undoubtedly the use of natural products, especially those of vegetable origin. Until the nineteenth century, the therapeutic resources were predominantly constituted by the use of plant parts and plant extracts. With the advancement of scientific and technological instruments that set the trend for the use of active substances in plants. In this work we present the phytochemical investigation of the branches and stems, and roots of Macroptilium lathyroides. This species is placed in the subfamily Papilionoideae of the Fabaceae family. The mixture of steroids sitosterol and stigmasterol (ML-1) was isolated from hexane extract of stems and branches. Lasiodiplodina (ML-2) and the mixture of steroid 6 β -hydroxy-4-stigmasta en-3-one and 6 β - hydroxy-4-stigmasta 4,22-dien-3-one (ML -3) were isolated from hexane extract of the roots and from the ethyl acetate extract of the roots were isolated de-O-methyl-lasiodiplodina (ML-4) and 4 ',5,7-triidroxiisoflavona (ML-5). The isolated compounds were identified by spectroscopic methods (IR, MS, 1H and 13C NMR), including two-dimensional techniques (HMBC, HSQC, COSY), and comparison with spectral data in the literature. The extracts were evaluated for larvicidal activity against Aedes aegypti, showing, therefore, inactive. This is the first report on the phytochemical study of Macroptilium lathyroides, as well as research larvicidal activity of the extracts.
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Otema, Anyanga Milton. "Phytochemical mediated resistance in sweetpotato to sweetpotato weevils." Thesis, University of Greenwich, 2015. http://gala.gre.ac.uk/18123/.
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This study evaluated sweetpotato resistance to sweet potato weevils (Cylas spp.) and investigated the phytochemicals that mediated this defence. New Kawogo, LIR302 and ARA228 were shown to be the most resistant based on stem and root damage. Significant differences were observed on the number of faecal droppings, feeding holes and eggs laid on the root in a choice and no-choice bioassays confirming that New Kawogo, LIR302 and ARA228 affected development and emergence of adult weevils. Six hydroxycinnamic acid esters, including hexadecylcaffeic, hexadecylcoumaric, octadecylcaffeic, octadecylcoumaric, heptadecylcaffeic and 5-O-caffeoylquinic acid esters were identified on the root surface and amounts of these differed significantly between resistant and susceptible varieties. The mean number of C. puncticollis and C. brunneus feeding holes, faecal droppings and egg laid on the root core were significantly different among the root cores treated with synthetic hydroxycinnamic acid esters. The study also showed that there were significant differences in the root volatiles of resistant and susceptible variety both before and after infestation. The larval survival of sweetpotato weevil was significantly affected by hydroxycinnamic acid esters treatment and Bt-toxin applied on the diet. There was also significant differences in percentage sweetpotato weevil root infestation among genotypes of the segregating population. The genotype by environment (GxE) interaction effect was also significant on the sweetpotato weevil damage on the stem portion of the sweetpotato vine indicating that weevil stem damage is dependent on the season. The mean number of sweetpotato weevil feeding holes differed significantly on the root of the genotypes of the segregating population in the feeding and oviposition bioassay. There was significant difference in total hydroxycinnamic acid (HCA) esters among the genotypes of the segregating population. The distribution of genotype mean total HCA ester concentration was skewed to the left and only one progeny, NKB257, had higher total HCA ester concentration than New Kawogo, the resistant mother used in the crossing. A weak but significant correlation between total HCA ester concentration and sweetpotato weevil root damage was observed signifying that resistance to sweetpotato weevils depended on other factors as well. The results are discussed in terms of how they might be incorporated into integrated pest management of sweetpotato weevils.
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Winter, P. J. D. "Species delimitations in cannomois: anatomical and phytochemical evidence." Thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/26453.
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Soriano, Imelda Rizalina. "Novel inducible phytochemical defences against plant parasitic nematodes /." Title page, table of contents and summary only, 2004. http://web4.library.adelaide.edu.au/theses/09PH/09phs7141.pdf.
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Wibberley, Mark Simon. "Growth and secondary metabolism in plant hairy root cultures." Thesis, University of the West of England, Bristol, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358245.
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Hoberg, Eva. "Phytochemical and analytical investigations of Vitex agnus-castus L /." [S.l.] : [s.n.], 1999. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=13285.
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Adefuye, Ogheneochuko Janet. "Anti-diabetic and phytochemical analysis of sutherlandia frutescens extracts." Thesis, Nelson Mandela Metropolitan University, 2016. http://hdl.handle.net/10948/3549.
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In Africa, the importance of medicinal plants in folklore medicine and their contribution to primary healthcare is well recognized. Across the continent, local herbal mixtures still provide the only therapeutic option for about 80% of the population. The vast floral diversity and the intrinsic ethnobotanical knowledge has been the backbone of localized traditional herbal medical practices. In Africa, an estimated 5400 of the 60000 described plant taxa possess over 16300 therapeutic uses. Similarly, with a therapeutic flora comprising of approximately 650 species, herbal medical practitioners in South Africa, make use of a plethora of plants to treat different human diseases and infections. Over the years, studies have identified numerous plant species with potential against chronic metabolic diseases including type 2 diabetes mellitus (T2DM). Globally, the incidence and prevalence of T2DM have reached epidemic proportions affecting people of all ages, nationalities and ethnicity. Considered the fourth leading cause of deaths by disease, T2DM is a global health crisis with an estimated diagnosis and mortality frequency of 1 every 5 seconds and 1 every 7 seconds respectively. Though the exact pathophysiology of T2DM is not entirely understood, initial peripheral insulin resistance in adipose tissue, liver, and skeletal muscle with subsequent pancreatic β-cell dysfunction resulting from an attempt to compensate for insulin resistance is a common feature of the disease. The current approach to treating T2DM is the use of oral antidiabetic agents (OAAs), insulin, and incretin-based drugs in an attempt to achieve glycaemic control and maintain glucose homeostasis. However, conventional anti-T2DM drugs have been shown to have limited efficacies and serious adverse effects. Hence, the need for newer, more efficacious and safer anti-T2DM agents. Sutherlandia frutescens subsp. microphylla is a flowering shrub of the pea family (Fabaceae/Leguminaceae) found mainly in the Western Cape and Karoo regions of Southern Africa. Concoctions of various parts of the plant are used in the management of different ailments including T2DM. However, despite extensive biological and pharmacological studies, few analyses exist of the chemical constituents of S. frutescens and no Triple Time of Flight Liquid Chromatography with Mass Spectrometry (Triple TOF LC/MS/MS) analysis has been performed. The initial aim of this study was to investigate the phytochemical profile of hot aqueous, cold aqueous, 80% ethanolic, 100% ethanolic, 80% methanolic and 100% methanolic extracts of a single source S. frutescens plant material using colorimetric and spectrophotometric analysis. The hot aqueous extractant was found to be the best extractant for S. frutescens, yielding 1.99 g of crude extract from 16 g fresh powdered plant material. This data suggests that application of heat and water as the extractant (hot aqueous) could play a vital role in extraction of bioactive compounds from S. frutescens and also justifies the traditional use of a tea infusion of S. frutescens. Colorimetric analysis revealed the presence of flavonoids, flavonols, tannins, and phenols in all extracts with varying intensity. The organic extracts 100% methanol, 80% and 100% ethanol exhibited high color intensity (+++) for flavonoids and flavonols respectively, while all the extracts exhibited a moderate color intensity (++) for tannins and phenols. Spectrophotometric analysis of S. frutescens extracts revealed that all the organic extracts contained a significantly higher concentration (in mg/g of extract) of flavonols and tannins when compared to the aqueous extracts. All extracts contained approximately equal levels of phenols. These data confirm the presence of all four groups of bioactive phytocompounds in the S. frutescens extracts used in this study, and also confirm that different solvent extractants possess the capability to differentially extract specific groups of phytocompounds. in individual extracts. Further comparison of these compounds with online databases of anti-diabetic phytocompounds led to the preliminary identification of 10 possible anti-diabetic compounds; α-Pinene, Limonene, Sabinene, Carvone, Myricetin, Rutin, Stigmasterol, Emodin, Sarpagine and Hypoglycin B in crude and solid phase extraction (SPE) fractions of S. frutesecens. Furthermore, using two hepatic cell lines (Chang and HepG2) as an in-vtro model system, the anti-T2DM properties of crude aqueous and organic extracts of S. frutescents was investigated and compared. Both aqueous and organic extracts of S. frutescens were found to decrease gluconeogenesis, increase glucose uptake and decrease lipid accumulation (Triacylglycerol, Diacylglycerol, and Monoacylglycerol) in Chang and HepG2 hepatic cell cultures made insulin resistant (IR) following exposure to high concentration of insulin and fructose. Using real-time quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), the aqueous and organic extracts of S. frutescens were confirmed to regulate the expression of Vesicle-associated membrane protein 3 (VAMP3), Mitogen-activated protein kinase 8 (MAPK8), and Insulin receptor substrate 1 (IRS1) in insulin resistant hepatic cells. IR-mediated downregulation of VAMP3, MAPK8, and IRS1 mRNA in IR HepG2 hepatic cell cultures was reversed in the presence of aqueous and organic extracts of S. frutescens. The hot aqueous extract displayed the highest activity in all the assays, while all the organic extracts displayed similar potency. In conclusion, this study reports that aqueous and organic extracts of S. frutescens possess numerous anti-diabetic compounds that can be further investigated for the development of new, more efficacious and less toxic anti-diabetic agents. The presence of multiple compounds in a single extract does suggest a synergistic or combinatorial therapeutic effect. These findings support the burgeoning body of in-vivo and in-vitro literature evidence on the anti-diabetic properties of S. frutescens and its use in folklore medicine.
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Juan-Badaturuge, Malindra. "Antioxidant activity and phytochemical evaluations of selected medicinal plants." Thesis, University of Greenwich, 2010. http://gala.gre.ac.uk/8098/.
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The methanolic crude extract of aerial parts of the plant Scrophularia nodosa was shown to have potent DPPH radical scavenging activity (IC50 = 48.75 ± 7.00 μg/ml). Activity-guided fractionation resulted in the isolation of three principal antioxidant compounds; acteoside, angoroside C and angoroside A. Acteoside (yield = 1.21%, IC50 = 15.2 μM) appeared to be the most abundant and most antioxidant-active. The potent antioxidant activity is in support of the traditional use of the plant for wound healing and anti-inflammatory conditions. The methanolic extract of aerial parts of Tanacetum vulgare has potent DPPH radical scavenging activity (IC50 = 37.00 ± 1.20 μg/ml). Activity-guided fractionation on the methanolic extract of T. vulgare resulted in the isolation of 3,5-di-caffeoylquinic acid (3,5-DCQA), axillarin and luteolin. 3,5-DCQA appeared to be the most abundant and most antioxidant-active compound (yield = 7.28%, IC50 = 9.7 μM). The potent antioxidant activity is in support of the traditional use of the herb for fever, rheumatic conditions and anti-inflammatory conditions. The methanolic crude extract of Cassia auriculata and its fractions were shown to have potent scavenging activity on DPPH, hydroxyl and hydroperoxide radicals, moderate superoxide radical scavenging activity and potent ion(III) reducing power. The activity-directed studies resulted in the isolation of kaempferol-3-0-β-D-rutinoside, kaempferol, luteolin, quercetin and unknown antioxidant inactive compound. The previously reported pharmacological aspects of the above flavonoids and flavonoid glycosides (anti-carcinogenic, anti-inflammatory, hyperglycaemic, antidiabetic) along with the shown antioxidant behaviour explain the traditional medicinal values of the plant. Cassia alata L crude extract and its fractions showed potent radical scavenging activity against formation of lipid peroxide radicals. The activity directed isolations resulted in the isolation of kaempferol along with p-hydroxybenzoic acid. These may contribute towards the traditional medicinal values of the plant as an antidiabetic, anti-microbial and for skin diseases.
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Mills, Charles. "A phytochemical-microbiological survey of the South American Bromeliaceae." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365874.
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Rungsimakan, Supattra. "Phytochemical and biological activity studies on Salvia viridis L." Thesis, University of Bath, 2011. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.557792.
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Six new compounds were isolated from the aerial and root parts of S. viridis L. cv. Blue Jeans. Two new triterpenoids, lup-20(29)-ene-2α-acetate-3β-ol, and lup-20(29)-ene-2α-ol-3β-acetate were found in the aerial part together with lup-20(29)-ene-2α-3β-diol, ursolic acid, oleanolic acid, β-sitosterol and β-sitosterol glucoside. Three new diterpenoids, 1-oxomicrostegiol, viroxocane, viridoquinone, together with five known diterpenoids, ferruginol, salvinolonyl 12-methyl ether, microstegiol, 7α-acetoxy-14-hydroxy-8,13-abietadiene-11,12-dione and 7α,14-dihydroxy-8,13-abietadiene-11,12-dione were found in roots. 1-Docosyl ferulate, 2'',3''-di-O-acetyl-martynoside and a mixture of 2-(4'-alkoxy-phenyl) ethyl alkanoates were also isolated from roots. Seven caffeic acid derivatives, five flavonoid glycosides, and salidroside were found in the crude aerial fraction. Four caffeic acid derivatives were known phenylpropanoids, i.e. trans-, cis-verbascoside, leucosceptoside A and martynoside, which are now reported in the genus Salvia for the first time. The others were caffeic acid, rosmarinic acid and 6-O-caffeoyl-glucose. A new flavonoid glycoside, luteolin-7-O-α-rhamnopyranosyl-(1→6)-β-galactopyranoside was also identified in the aerial part with four known flavone glycosides: luteolin-7-O-β-glucopyranoside, luteolin-7-O-β-galactopyranoside, luteolin-7-O-rutinoside and apigenin-7-O-β-glucopyranoside. Verbascoside (acteoside), which is a major component in this plant, showed a significant protective effect against UVA induced damage in a human skin fibroblast model in vitro. It exhibited 1.4 fold protective effect against UVA induced necrosis with 1.4 fold higher in cell survival. 50 μM Verbascoside showed the same protective effect as 100 μM DFO at a high intensity UVA dose (500 kJ/m2). Further determination of organelle specific protection suggested a mechanism of action in mitochondria. Two terpenoids, lup-20(29)-ene-2α-acetate-3β-ol and 7α,14-dihydroxy-8,13-abieta-diene-11,12-dione, exhibited antibacterial activity against Enterococcus faecalis with MIC 50 μM. Microstegiol was also active against Staphylococcus aureus with MIC 50 μM. Ursolic acid, oleanolic acid and ferruginol showed appreciable antibacterial activity against three Gram-positive bacteria, Staphylococcus aureus, Enterococcus faecalis, and Bacillus cereus with MIC 12.5-50 μM. The other diterpenoids were active against all three Gram-positive bacteria with MIC 100-200 μM. None of crude fractions was active against three Gram-negative bacteria, Klebsiella pneumoniae, Proteus vulgaris, and Escherichia coli.
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Marques, Ricardo de AraÃjo. "Phytochemical and Biological Investigation of Humirianthera ampla Miers (Icacinaceae)." Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7212.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorThe phytochemical investigation of the roots of Humiranthera ampla (Icacinaceae) resulted in the isolation and identification of a mixture of beta-sitosterol and stigmasterol, annonalide, lupeol and the 3-beta-O-beta-D-glucopyranosyl sitosterol. The structures of these compounds were established by spectrometric analysis (IR, MS, NMR 1H and 13C) including bidimensional NRM techniques (COSY, HMQC, HMBC and NOESY) and for comparison with data described in the literature. All extracts were tested using the Ellman assay. Only ethyl acetate extract and their fractions showed acetylcholinesterase inhibition. The antioxidant capacity of the extracts were measured as method described by Owen et al, 2001. The ethanolic extract was the most active. The ethyl acetate extract showed xanthine oxidase inhibition.
A investigaÃÃo fitoquÃmica das raÃzes de Humirianthera ampla (Icacinaceae) resultou no isolamento e identificaÃÃo da mistura de beta-sitosterol e estigmasterol, annonalida, lupeol e 3-beta-O-beta-D-glicopiranosil sitosterol. As estruturas destes compostos foram estabelecidas por anÃlise espectromÃtricas (IV, EM, RMN 1H e 13C) incluindo tÃcnicas de RMN bidimensional (COSY, HMQC, HMBC E NOESY) e por comparaÃÃo com dados registrados na literatura. Todos os extratos foram testados usando o ensaio de Ellman. Somente o extrato acetato de etila e suas fraÃÃes mostraram inibiÃÃo da acetilcolinesterase. A capacidade antioxidante dos extratos foi avaliada pelo mÃtodo descrito por Owen et al, 2001. O extrato etanÃlico foi o mais ativo. O extrato acetato de etila mostrou inibiÃÃo da enzima xantina oxidase.
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Donegá, Mateus Augusto. "Agronomic and phytochemical aspects of cilantro and stevia crops." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-05022014-095330/.
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The market of medicinal plants and herbs such as cilantro (Coriandrum sativum) and stevia (Stevia rebaudiana) has been growing due to the demand of the food, chemical and pharmaceutical industries. Leaves of C. sativum are used by many countries in the preparation of food and in folk medicine. The essential oil from the leaves has potential for use in the food industry as an antimicrobial agent and as a condiment to mask undesirable odors and flavors. Studies were conducted to evaluate the activity of the essential oil of cilantro against Leishmaniasis, and the results showed that the essential oil and its major compounds inhibited the growth of L. donovani in its different forms, indicating potential use of this plant for the production of new drugs against Leishmaniasis. From these results, another study was conducted to evaluate five materials of cilantro, a cultivar and four germplasm accessions from the North American Department of Agriculture regarding the quality of the raw material for the food and pharmaceutical industries. The materials with the highest potential to use were AMES 18596 and PI193770 for producing larger amount of dry biomass and the highest production of major compounds, which are desirable by industries. Stevia is a species with high potential to be consumed by diabetics and obese, it is a source of diterpene glycosides used as natural sweeteners. Sweeteners derived from stevia are ingredients in the production of foods, juices and soft drinks in Asia, Europe and in the Americas. The compounds responsible for the sweetness of stevia leaves are well characterized in the literature. However, good agronomic practices are still poorly studied. Some countries have worked on improving this culture and have achieved cultivars with higher yield. In the area of plant nutrition, calcium is one of the most important nutrients for the production of biomass and stevioside in stevia plants. Thus, a preliminary study was conducted to test the effect of calcium applied in nutrient solution in stevia yield, and stevioside and rebaudioside in hydroponic system. The leaf, stem and shoot biomass yield, by stevia plants were influenced by Ca rates in nutrient solutions and were maximal with 7.0, 5.7, 6.2 mmol L-1 of Ca, respectively. The production of stevioside and rebaudioside A was maximal with addition of 4.0 mmol of Ca L-1.O mercado de plantas medicinais, condimentares e aromáticas tais como coentro (Coriandrum sativum) e estévia (Stevia rebaudiana) vêm crescendo devido à demanda das indústrias alimentícias, químicas e farmacêuticas. As folhas C. sativum são utilizadas por diversos países no preparo de alimentos e na medicina popular. O óleo essencial das folhas tem potencial para utilização na indústria de alimentos como agente antimicrobiano e como condimento para mascarar cheiros e sabores indesejáveis. Estudos foram realizados para avaliar a atividade do óleo essencial de coentro contra a leishmaniose, e os resultados revelaram que o óleo essencial e seus compostos majoritários inibiram o crescimento L. donovani em suas diferentes formas, indicando potencial de uso dessa planta para a produção de novos medicamentos contra Leishmaniose. A partir desses resultados, outro estudo foi realizado com o objetivo de avaliar cinco materiais de coentro, uma cultivar e quatro acessos do germoplasma do Departamento de Agricultura norte americano quanto à qualidade da matéria prima para as indústrias de alimentos e farmacêuticas. Os materiais variaram entre si quanto à produção de biomassa, acúmulo de nutrientes e produção de aldeídos alifáticos tais como (E)- 2-decenal, (E)- 2-dodecenal. Os materiais que apresentaram maior potencial de uso foram AMES 18596 e PI193770, pois, produziram maior quantidade de massa seca e produção de compostos majoritários, que são os desejáveis pelas indústrias. Quanto à estévia, essa espécie apresenta elevado potencial para ser usado por pessoas diabéticas e obesas, pois é fonte de diterpenos glicosídicos usados como adoçantes naturais. Os adoçantes derivados de estévia são usados na produção de alimentos, sucos e refrigerantes em diversos países asiáticos, europeus e no continente americano. Os compostos responsáveis pelo dulçor das folhas de estévia são bem caracterizados pela literatura, entretanto, as boas práticas agronômicas ainda são pouco estudadas. Alguns países trabalharam no melhoramento dessa cultura e conseguiram alcançar cultivares mais produtivas. Na área de nutrição, o cálcio está entre os nutrientes mais importantes para a produção de esteviosídeo e produção de biomassa de estévia. Assim, um estudo preliminar foi conduzido com o objetivo de estudar o efeito do cálcio aplicado em solução nutritiva na produção de estévia, e de esteviosídeos e rebaudiosídeos, em sistema hidropônico. A produção de folhas, caule e parte aérea por plantas de estévia foi influenciada por níveis de Ca na solução nutritiva e foram máximos com as doses de 7,0, 5,7, 6,2 mmol L-1 de Ca, respectivamente. A produção de esteviosídeo e rebaudiosídeo A foi máxima com a adição de 4,0 mmol L-1 de Ca.
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Chen, Dianne Tzu-Hsiu. "Phytochemical studies on traditional medicinal plants with antimalarial activities." Master's thesis, University of Cape Town, 1997. http://hdl.handle.net/11427/21853.
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The active antimalarial principles of three traditional medicinal plants, Passerina obtusifolia (Thymelaeaceae), Tetradenia riparia (Labiatea) and Xerophyta retinervis (V elloziaceae) were investigated by employing bioassay guided fractionation. Two novel compounds and five known constituents were isolated from the active fractions of these three plants. The types of compounds isolated included: three triterpenoids (20(29)-Lupene-3α,28- diol (30), 20(29)-Lupene-3α, 16β,28-triol (32) and 3β-Hydroxy-20(29)-Lupen-28-oic acid (42)); two diterpenoids (8-Abietene-7 β,13 β -diol (45) and cariocal (51)); one flavonoid ( 5-Hydroxy:.4' ,6, 7-trimethoxyflavone ( 44)) and one flavonolignan ( 11-0- acetyl hydnocarpin (62)). In addition, one analogue of 7α-hydroxyroyleanone (41) (which was previously isolated from T riparia and was found to be the active antimalarial principle of the plant) was prepared.
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Reynertson, Kurt Allerslev. "Phytochemical analysis of bioactive constituents from edible Myrtaceae fruits /." View online, 2007. http://home.earthlink.net/~myrtaceae/Reynertson_dissertation.pdf.
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Thesis (Ph. D.)--City University of New York, 2007.Includes bibliographical references (leaves 100-120) and index. Also available for educational and research purposes in PDF format on the Internet.
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Shukla, Yatin Jagannath. "Phytochemical studies of botanicals : Hoodia Gordonii and Caralluma species /." Full text available from ProQuest UM Digital Dissertations, 2009. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1799143131&SrchMode=1&sid=7&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1268341330&clientId=22256.
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Thesis (Ph.D.)--University of Mississippi, 2009.Typescript. Vita. Major professor: Dr. Ikhlas A. Khan Includes bibliographical references (leaves 277-303). Also available online via ProQuest to authorized users.
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Goggans, Mallory. "Elucidating Tomato Steroidal Glycoalkaloid Metabolism and Effects of Consumption onthe Gut Microbiome in a Pig Model." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1594824484770731.
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Volken, Maria Carmen. "Biological and phytochemical investigations of Euphorbiaceae from Papua New Guinea /." [S.l.] : [s.n.], 1999. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=13294.
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Burt, Andrew J. "Phytochemical mediation of post-harvest insect resistance in tropical maize." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/22632.
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Alqahtani, Alaa. "Phytochemical investigation of members of the Asparagaceae and Euphoriaceae families." Thesis, University of Surrey, 2015. http://epubs.surrey.ac.uk/808763/.
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The Asparagaceae family is richly represented in the southern African region and has approximately 900 species. It consists of four tribes, the Hyacintheae, Urgineeae, Ornithogaleae, and Oziroeeae. Members of the Asparagaceae are widely used in traditional remedies for the treatment of several ailments, such as infections, rheumatism, inflammation and disorders associated with the central nervous system. Different species belonged to Urgineeae tribe (Rhodocodon campanulatus, R. calcicola), Hyacintheae tribe (Chionodoxa luciliae (Gigantea Hort)), Ornithogaleae tribe (Ornithogalum pyramidale and Avonsera convallarioides) have been selected for the present phytochemical study. The bulbs of R. campanulatus yielded five new compounds, a bufadienolide (RC.1), a homoisoflavonoid (RC.2) and two acetylated derivatives of a homosoflavonoid (RC.2a & RC.2b) and an acetylated neolignan (RC.3a). The bulbs of R. calcicola gave two known bufadienolides (RA.1 & RA.2). C. luciliae yielded ten compounds, including scillascillin-type homoisoflavonoids (CL.1-CL.5a), 4-chromanone (CL.4), p-hydroxybenzaldehyde (CL.6), 3-benzyl-chromanone type (CL.7-CL.9) and 3-benzylidene-4-chromanone (CL.10). O. pyramidale yielded new cardenolide glycosides (OP.1). A. convallarioides gave a known polyhydroxylated compound, polybotrin (AV.1), a purine nucleoside, adenosine (AV.2) and trans N-p-coumaroyloctopamine (AV.3). The Euphorbiaceae family is a large and diverse family which comprises 340 genera. Several species belonging to the Croton genus are employed as traditional medicinal agents in Africa, Asia and South America. The Croton species are popularly used to treat cancer, hypertension, inflammation, rheumatism, bleeding gums, malaria, asthma, diabetes and ulcers. In this study, three Croton species, C. megalocarpus, C. menyhartii and C. rivularis have been investigated for their chemistries. The roots of C. megalocarpus gave ten compounds, six diterpenoid compounds belonged to ent-clerodane (CP.1-CP.6), halimane (CP.7) and ent-abietane (CP.8-CP.9) and a triterpenoid, lupeol (CP.10). The leaves of C. menyhartii gave two flavonoids: (CM.1-CM.2) and 4-hydroxy-1-methyl-2-pyrrolidinone (CM.3) as well as large quantities of sitosterol. The leaves of C. rivularis gave one acyclic triterpene, squalene (CR.1) and an acyclic diterpenoids, phytol (CR.2). The structures of these compounds were determined using FTIR, MS, 1D, 2D NMR studies and CD analysis. Compounds RC.1 and RC.3a, and compound OP.1, were screened against the NCI60 cancer cell lines. Compound OP.1 showed significant growth inhibition of cancer cell lines at five dose concentration level with good responses at the GI50, TGI and LC50 parameters. The homoisoflavonoids isolated in this study from C. luciliae and R. campanulatus were tested for their anti-angiogenic inhibition ability, CL.10 and RC.2b showed significant anti-angiogenic inhibition with GI50 values of 40.4 and 128 μM respectively.
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Assinewe, Valerie Ann. "Phytochemical variation and immunopharmacology of Panax quinquefolius L. (American ginseng)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2002. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ66118.pdf.
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Ramos-Jerz, María del Refugio. "Phytochemical analysis of avocado seeds (Persea americana Mill., c.v. Hass)." Göttingen Cuvillier, 2007. http://d-nb.info/98608638X/04.
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Gordien, Andrâea Y. "Phytochemical and antimicrobial studies of Scottish plants and fungal endophytes." Thesis, University of Strathclyde, 2010. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=14347.
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Sanchez-Medina, Alberto. "Phytochemical and pharmacological studies on some endemic Yucatecan medicinal plants." Thesis, University of Greenwich, 2007. http://gala.gre.ac.uk/6291/.
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Four endemic medicinal plants from the Yucatan peninsula belonging to genera with little pharmacological and phytochemical reported information and used for medicinal purposes by local communities were selected. The species selected included Jacquinia flammea Millsp. ex Mez, Sideroxylon foetidissimum Jacq. subsp. gaumeri, Serjania yucatanensis Standl., and Serjania adiantoides Radlk. The root, stem/bank and leaves of each plant species were extracted using ethanol and the resulting crude extracts were tested for their cytotoxic effect using the modified MTT (3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) assay followed by a bioassay-guided fractionation of the most active extracts in order to identify the active metabolites. The initial cytotoxic evaluation against HeLa cells at two fixed concentrations (100 and 33.3 µg/mL) identified the root extracts f J. flammea, S. foetidissimum subsp. gaumeri and S. yucatanensis, and the stem/bank extract of S. adiantoides as the most active extracts. The crude extract of roots of J. flammea was subjected to solvent partition using solvents of ascending polarity (pet. ether, CHCI3, EtOAc, BuOH and water). The resulting fractions were tested for their cytotoxic activity. The water fraction of the solvent partition showed the strongest activity against HeLa cells (IC50 = 28.61 ± 2.27 µg/mL). When tested against RAW 264.7 cells, the water fraction also showed significant activity (IC50 = 10.60 ± 1.83 µg/mL). The water fraction was subjected to chromatographic fractionation using open silica gel columns resulting in the isolation of a saponin as the most active metabolite against RAW 264.7 cells (IC50 = 4.76 ± 0.32 µg/mL). The isolated compound was identified using 1D (1H and 13C and DEPT-135) and 2D (COSY, HMBC, HSQC and NOESY and ROESY) NMR and mass spectrometry analysis as sakurasosaponin. The molluscicidal and antifungal activities of sakurasosaponin have been reported but no studies on its cytotoxic activity have been previously reported. The crude extract of roots of S. foetidissimum subsp. gaumeri was subjected to solvent partition using solvents of ascending polarity (pet. ether, CHC13, EtOAc, and BuOH). The resulting fractions were tested for their cytotoxic activity. The BuOH extract of S. foetidissimum subsp. gaumeri showed the strongest activity against RAW 264.7 cells (IC50 = 35.12 ± 4.32 µg/mL) and it was subjected to further chromatographic fractionation using open silica gel columns yielding mixtures of saponin-containing fractions. The crude extract of roots of S. yucatanensis was subjected to solvent partition using solvents of ascending polarity (pet. ether, CHCI3, EtOAc, and BuOH). The resulting fractions were tested for their cytotoxic activity. The crude extract of S. adiantoiodes did not show cytotoxic activity when tested against RAW 264.7 cells.
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Osborne, S. J. "Phytochemical and anatomical investigations in the genera Acronychia and Maclurodendron." Thesis, University of Sunderland, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234871.
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