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Müller, Adrienne Carmel. "African traditional medicine-antiretroviral interactions : effects of Sutherlandia frutescens on the pharmacokinetics of Atazanavir." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1013373.
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In response to the urgent call for investigations into antiretroviral (ARV)-African traditional medicine (ATM) interactions, this research was undertaken to ascertain whether chronic administration of the ATM, Sutherlandia frutescens (SF) may alter the bioavailability of the protease inhibitor (PI), atazanavir (ATV), which may impact on the safety or efficacy of the ARV. Prior to investigating a potential interaction between ATV and SF in vitro and in vivo, a high performance liquid chromatography method with ultraviolet detection (HPLC-UV) was developed and validated for the bioanalysis of ATV in human plasma and liver microsomes. An improved and efficient analytical method with minimal use of solvents and short run time was achieved in comparison to methods published in the literature. In addition, the method was selective, linear, accurate and precise for quantitative analysis of ATV in these studies. Molecular docking studies were conducted to compare the binding modes and affinities of ATV and two major SF constituents, Sutherlandioside B and Sutherlandin C, with the efflux transporter, P-glycoprotein (P-gp) and the CYP450 isoenzyme, CYP3A4 to determine the potential for these phytochemicals to competitively inhibit the binding of ATV to these two proteins, which are mediators of absorption and metabolism. These studies revealed that modulation of P-gp transport of ATV by Sutherlandioside B and Sutherlandin C was not likely to occur via competitive inhibition. The results further indicated that weak competitive inhibition of CYP3A4 may possibly occur in the presence of either of these two SF constituents. The Caco-2 cell line was used as an in vitro model of human intestinal absorption. Accumulation studies in these cells were conducted to ascertain whether extracts and constituents of SF have the ability to alter the absorption of ATV. The results showed that the aqueous extract of SF significantly reduced ATV accumulation, suggesting decreased ATV absorption, whilst a triterpenoid glycoside fraction isolated from SF exhibited an opposing effect. Analogous responses were elicited by the aqueous extract and a triterpenoid glycoside fraction in similar accumulation studies in P-gp overexpressing Madin–Darby Canine Kidney Strain II cells (MDCKII-MDR1), which signified that the effects of this extract and component on ATV transport in the Caco-2 cells were P-gp-mediated. The quantitative analysis of ATV in human liver microsomes after co-incubation with extracts and components of SF was conducted to determine the effects of SF on the metabolism of ATV. The aqueous and methanolic extracts of SF inhibited ATV metabolism, whilst the triterpenoid glycoside fraction had a converse effect. Analogous effects by the extracts were demonstrated in experiments conducted in CYP3A4-transfected microsomes, suggesting that the inhibition of ATV metabolism in the liver microsomes by these SF extracts was CYP3A4-mediated. A combination of Sutherlandiosides C and D also inhibited CYP3A4-mediated ATV metabolism, which was in contrast to the response elicited by the triterpenoid fraction in the liver microsomes, where other unidentified compounds, shown to be present therein, may have contributed to the activation of ATV metabolism. The in vitro studies revealed the potential for SF to alter the bioavailability of ATV, therefore a clinical study in which the effect of a multiple dose regimen of SF on the pharmacokinetics (PK) of a single dose of ATV was conducted in healthy male volunteers. The statistical analysis showed that the 90 % confidence intervals around the geometric mean ratios (ATV + SF/ATV alone) for both Cmax and AUC0-24 hours, fell well below the lower limit of the "no-effect" boundary of 0.8 – 1.25, implying that the bioavailability of ATV was significantly reduced in this cohort of subjects. It may thus be concluded that if the reduction in bioavailability observed in this clinical study is found to be clinically relevant, co-administration of SF commercial dosage forms and ATV in HIV/AIDS patients may potentially result in subtherapeutic ATV levels, which may in turn contribute to ATV resistance and/or treatment failure. This research has therefore highlighted the potential risk for toxicity or lack of efficacy of ARV regimens which may result when ATMs and PIs are used concurrently and that patients and health care practitioners alike should be aware of these perils.
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Van, Gend Tania Anli. "Effect of a South African medicinal plant on antiretroviral drug induced abnormalities in rats." Thesis, Nelson Mandela Metropolitan University, 2008. http://hdl.handle.net/10948/1080.
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The worldwide AIDS epidemic is known to have had a profoundly negative social, economic and personal impact and has taken a heavy toll on existing health care systems, particularly in developing countries. South Africa is experiencing an HIV epidemic with enormous social and economic consequences. Lopinavir/ritonavir antiretroviral treatment has been accredited with having a significantly positive effect and is a key advance in controlling HIV morbidity and mortality. An indigenous South African medicinal plant, Sutherlandia frutescens, known for its anti-diabetic properties and immune-boosting effects, is used for treating HIV positive patients suffering from opportunistic infections. Despite the use of the medicinal plant extract as homeotherapeutic medication, there is little evidence of toxicity testing that identifies its potential for interaction with antiretroviral drugs. However, scientific data relating to the mechanism through which Sutherlandia frutescens acts on the immune system has not been comprehensively documented. The aim of this study was to investigate lopinavir/ritonavir induced metabolic abnormalities in rats and whether the introduction of a plant extract of Sutherlandia frutescens would counteract the side effects of ARV medication. The results indicated that the rodents did not become insulin resistant, however, biochemical analysis indicated that extended ARV drug treatment would have caused insulin resistance. Significant morphological changes were found in the livers, kidneys and pancreases of rats exposed to the lopinavir/ritonavir. Rats exposed to the Sutherlandia frutescens plant extract showed improved histopathology with minimal abnormalities.
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Mukinda, James Tshikosa. "Acute and chronic toxicity of the flavonoid-containing plant, Artemisia afra in rodents." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
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The aim of this study was to investigate the possible toxicity of the flavonoid-containing plant, Artemisia afra and especially establish the safety of the aqueous extract of this plant after acute and chronic administration to mice and rats respectively.
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Miyake, Mônica Aidar Menon. ""Efeitos da infusão de Luffa operculata sobre o epitélio e a atividade mucociliar do palato isolado de rã"." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/5/5143/tde-20102005-113139/.
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Luffa operculata é uma planta medicinal popularmente usada para tratamento de rinites e rinossinusites. A infusão de seu fruto seco é usada no nariz, liberando secreção mucosa profusa, mas pode causar irritação, epistaxe ou anosmia. Avaliamos os efeitos de diferentes concentrações da infusão do fruto seco da Luffa operculata na velocidade de transporte mucociliar (VTM), freqüência de batimento ciliar (FBC), diferença de potencial transepitelial (DPT) e morfologia do epitélio (microscopia de luz e eletrônica de transmissão), no modelo do palato isolado de rã. Os resultados apontam para dano epitelial dose-dependente no epitélio mucociliar, sugerindo que ela seja potencialmente nociva à mucosa nasal humanaLuffa operculata is a medicinal plant popularly used for treatment of rhinitis and rhinosinusitis. Its dry fruit infusion is used into the nose, delivering profuse mucous secretion, but may cause nasal mucosa irritation, epistaxis or anosmia. We evaluated the effects of different concentrations of Luffa operculata dry fruit infusion on mucociliary transport velocity (MTV), ciliary beat frequency (CBF), transepithelial potential difference (TPD) and epithelial morphology (light and electron transmission microscopy) of the isolated frog palate preparation. Results pointed to dose-dependent epithelial damage on mucociliary epithelium, suggesting that it is potentially noxious to the human nasal mucosa
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Dias, Araujo Mazzari A. L. "In vitro effects of selected medicinal plants shortlisted for clinical use in the Brazilian public health system in CYP3A4 mRNA gene expression, glutathione levels and P-glycoprotein activity and their implications for herb-drug interactions." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1535229/.
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The Brazilian Unified Public Health System (SUS) shortlisted various plant species of interest (RENISUS) for future clinical use. However, very little is known about their effects on metabolic and transporter proteins, which could potentially lead to herb-drug interactions (HDI). To evaluate this, we conducted in vitro preclinical studies on twenty-four plant extracts to disclose their effects on CYP3A4 mRNA gene expression, intracellular glutathione (GSH) levels, inhibition of γ-glutamyl transferase (GGT) in HepG2 cells and P- glycoprotein (P-gp) activity in vincristine resistant Caco-2 (Caco-2 VCR) cells. We also investigated whether four Brazilian native species were able to activate the human pregnane X receptor (hPXR) in transiently co-transfected HeLa cells. This preclinical research showed that all but two plant extracts were able to modulate at least one of the selected targets. CYP3A4 mRNA gene expression in HepG2 cells was significantly affected by half of the extracts. The antagonistic effect of Solanum paniculatum L. on hPXR could explain its ability to inhibit CYP3A4. GSH levels were affected by 80% of the extracts. There was depletion of intracellular GSH levels by Cordia verbenacea A. DC., Costus spicatus (Jacq.) Sw., Persea americana Mill., Salix alba L., Schinus terebinthifolia Raddi and Syzygium jambolanum (Lam.) DC. accompanied because of the inhibition of GGT activity. P-gp activity was modulated in a significant manner by 17% of the extracts. The approaches used for the conduction of in vitro preclinical studies in herbal medicines revealed a series of challenges faced especially by academics in order to anticipate cases of HDI. Clinicians have also to consider the presence of intrinsic factors such as genetic polymorphisms in each patient. The possible presence of undesirable interactions between RENISUS herbal medicines and essential drugs in SUS need eventually be clinically confirmed to attest our observed in vitro effects.
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Mogatle, Seloi. "African traditional medicines-antiretroviral drug interactions: the effect of African potato (Hypoxis hemerocallidea) on the pharmacokinetics of efavirenz in humans." Thesis, Rhodes University, 2009. http://hdl.handle.net/10962/d1003251.
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African Potato (Hypoxis hemerocallidea), (AP) is an African traditional medicine (TM) that is commonly used for various nutritional/medicinal purposes and also by people infected with the human immuno deficiency virus HIV and AIDS patients as an immune booster. The use of AP has also been recommended by the former Minister of Health of South Africa for use by HIV positive people. The main phytochemical component of AP is a norlignan glucoside, hypoxoside, and other relatively minor components have also been reported. A recent in vitro study reported the effects of AP extracts, hypoxoside and rooperol (the metabolite of hypoxoside) on human metabolic enzymes such as the cytochrome P450 (CYP450) group of enzymes and also on the transporter protein, p-glycoprotein (P-gp). This research focussed on investigating the clinical significance of those in vitro effects on the pharmacokinetics of efavirenz (EFV) in humans. EFV was chosen as the substrate drug because it is in first-line regimen of treatment of HIV/AIDS in South Africa, and also has been reported to be a substrate for the specific CYP isozymes, 3A4 and 2B6, in common with APs metabolic involvement with 3A4. A high performance liquid chromatography method with ultra-violet detection (HPLC-UV) for the quantitative determination of EFV in plasma was developed and successfully validated according to international standards with good reproducibility, accuracy, recovery, linear response and requisite sensitivity. The preparation of the plasma samples for analysis was effected by using a simple and rapid precipitation method, and the mobile phase consisted of readily available solvents. EFV in plasma samples was found to be stable under the relevant storage conditions studied. The oral dose of AP, administered as a freshly prepared traditional decoction, was standardised based on the hypoxoside content, and the quality of all the AP decoctions was analysed immediately prior to administration, using a validated HPLC-UV method. A single dose, two-phase sequential study was conducted over a period of 31 days in 10 healthy volunteers. The clinical study was approved by the Rhodes University Ethical Standards Committee, and all the participants agreed to the conditions of the study by giving their informed consent. On day 1 of the study, human subjects were administered a 600 mg EFV tablet and blood samples were collected before dosing and at various intervals over a period of 48 hr post dosing. From day 16, a traditionally prepared AP decoction was administered daily at a standardized dose of 15 mg/kg/day per subject until day 30. On day 29, volunteers were administered a single 600 mg dose of EFV as was done on day 1. Plasma samples were harvested immediately after blood sample collection and frozen at -80 ºC until assayed. Geometric mean ratios of relevant pharmacokinetic parameters, Cmax (maximum plasma concentration achieved following dosing) and AUC0-48 (area under the curve of a plot of drug plasma concentrations versus time representing the extent of absorption) of EFV before and after co-administration of 14 successive daily doses of AP were compared and evaluated to determine whether an interaction had occurred. All subjects completed the study and the geometric mean ratios of Cmax and AUC0-48 were 97.30 and 102.82 with corresponding 90% confidence intervals (CIs) of 78.81-120.14% and 89.04-118.80%, respectively. Whereas the acceptance criteria for the ratios of the AUCs fell within the preset 90% CIs indicating no interaction, the Cmax ratios fell outside the limits. Although the protocol was developed in accordance with the United States of America Food & Drug Administration’s Guidance for Drug Interactions, a priori stating that both criteria need to fall within the acceptance limits to indicate no interaction, an argument is presented to waive the Cmax requirement for the declaration of an interaction. As a result, the pharmacokinetic data generated during this study indicated that the effect of AP on the pharmacokinetics of EFV is not clinically significant. Hence, co-administration of AP is unlikely to affect the clinical use of EFV. In summary the objectives of this project were: 1. To develop and validate a suitable HPLC-UV method for the quantitative determination of EFV in plasma. 2. To perform a mini-validation of the determination of hypoxoside for use as a marker in the quality control and standardisation of AP decoctions. 3. To conduct a clinical interaction study in order to determine whether AP affects the pharmacokinetics of EFV following concurrent administration. 4. To apply the validated HPLC-UV method to determine plasma concentrations of EFV in plasma of human subjects. 5. To use appropriate statistical methods and treatments such as a non-compartmental pharmacokinetic analysis to determine the occurrence of an interaction.
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Fontenele, Juvenia Bezerra. "Estudo farmacolÃgico da fraÃÃo hexÃnica de Lonchocarpus sericeus (Poir) Kunth e seus constituintes quÃmicos, lonchocarpina e derricina." Universidade Federal do CearÃ, 2004. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=33.
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FundaÃÃo de Amparo à Pesquisa do Estado do CearÃCoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
O gÃnero Lonchocarpus à bastante conhecido e amplamente estudado, porÃm nÃo hà registros na literatura cientÃfica dos usos farmacolÃgicos da espÃcie Lonchocarpus sericeus (Poir.) Kunth, (Leguminosae Papilionaceae). Estudos quÃmicos demonstraram que a fraÃÃo hexÃnica das cascas das raÃzes de L. sericeus (FLS) à rica nas chalconas: lonchocarpina (LCC) e derricina (DRC). O objetivo deste trabalho foi investigar os efeitos tÃxicos e as aÃÃes farmacolÃgicas da FLS e de sua chalconas LCC e DRC. A DL50 para FLS em camundongos foi de 781,5 mg/kg por v.o. e 446,2 mg/kg, por via i.p. A FLS e a DRC mostraram efeito inibitÃrio concentraÃÃo-dependente sobre o desenvolvimento embrionÃrio de ovos de ouriÃo-do-mar Lytechinus variegatus. A FLS, LCC e DRC apresentaram ainda atividade citotÃxica sobre cÃlulas de leucemia linfocÃtica de origem humana. A FLS, administrada por via sistÃmica, apresentou atividade antiedematogÃnica nos modelos de edema de pata induzidos por carragenina (Cg) e levedura de cerveja, mas nÃo sobre aqueles induzidos por dextrano ou bradicinina. O efeito da FLS no edema por Cg nÃo foi modificado pela associaÃÃo com a indometacina ou L-NAME, mostrando que a mesma parece nÃo interferir com a via da COX ou do sistema NO. Entretanto, este efeito da FLS foi potencializado pela pentoxifilina (PTX) evidenciando uma possÃvel inibiÃÃo da FDE e/ou da sÃntese de citocinas inflamatÃrias como o TNF-alfa. Apesar de ter inibido significativamente a migraÃÃo de neutrÃfilos na cavidade peritoneal de ratos induzida por Cg, a FLS apresentou um efeito inibitÃrio bem maior sobre Ãquela induzida por fMLP, demonstrando que a mesma alÃm de bloquear a sÃntese e/ou liberaÃÃo de mediadores inflamatÃrios como PGs, LTs e citocinas, pode tambÃm bloquear uma das etapas da migraÃÃo ou ainda, inibir alguma das molÃcula de adesÃo envolvidas neste processo. A FLS tambÃm reduziu o dano tissular induzido por Ãcido acÃtico em ratos, evidenciado atravÃs de seu efeito inibitÃrio sobre a atividade da MPO. Entretanto, a mesma nÃo foi capaz de suprimir a formaÃÃo do tecido de granulaÃÃo, induzida por pellet de algodÃo, onde as PGs desempenham um papel essencial. A atividade antinociceptiva da FLS tambÃm foi observada em modelos experimentais de dor como teste das contorÃÃes abdominais induzidas pelo Ãcido acÃtico e teste da formalina, em camundongos. Todavia, a FLS nÃo modificou a resposta nociceptiva ao estÃmulo tÃrmico no teste da placa quente. Este efeito antinociceptivo da FLS independe do sistema opiÃide e da via do NO, e tambÃm nÃo envolve a participaÃÃo do componente adrÃnergico, porÃm alÃm de outros mecanismos, a inibiÃÃo da FDE e/ou da sÃntese de citocinas como TNF-alfa parecem exercer um papel importante na antinocicepÃÃo da FLS. A atividade antiagregante plaquetÃra da FLS, LCC e DRC tambÃm foi estudada e os resultados demonstraram que as mesmas possuem efeito inibitÃrio da agregaÃÃo in vitro em plasma humano rico em plaquetas, frente aos agonistas ADP, colÃgeno, trombina, Ãcido araquidÃnico e adrenalina. O efeito antiagregante plaquetÃrio da FLS, LCC e DRC foi potencializado pela PTX, um inibidor da fosfodiesterase de AMPc, mas nÃo pela L-arginina ou pelo Ãcido acetilsalicÃlico. Desta forma, a FLS possui atividade citotÃxica, antiinflamatÃria, analgÃsica e antiagregante plaquetÃria. Estes efeitos parecem ser mediados pelas chalconas LCC e DRC, presentes na FLS.
The Lonchocarpus genus is well known and much studied though there is no record on scientific publications about the pharmacological properties of the species Lonchocarpus sericeus (Poir.) Kunth, (Leguminosae Papilionaceae). Chemical research determined that the hexanic fraction from root bark of L. sericeus (FLS) is rich in two chalcones: lonchocarpin (LCC) and dericin (DRC). This workâs purpose was to investigate the toxical effects and the pharmacological actions of FLS and its chalcones LCC e DRC. The LD50 of FLS in mice was 781,5 mg/kg, p.o. and 446,2 mg/kg, i.p. FLS and DRC showed concentration-dependent inhibition on the development of the sea urchin Lytechinus variegatus eggs. Additionaly, FLS, LCC and DRC showed cytotoxic activity on human lymphocytic leukemia cells. Sistemically administered FLS demonstrated anti-edematogenic activity on carragenan (Cg)- and yeast-induced rat paw edema models, but did not show any effect on dextran- or bradikinin-induced rat paw edema models. The FLS effect on Cg model was not modified by treatment with indomethacin or L-NAME what implies that it seems not to affect COX or NO pathways. Notwithstanding, this FLS effect was indeed potentiated by pentoxifylline (PTX) suggesting a possible phosphodiesterase (PDE) or TNF-alfa like cytokines inhibition. Even though FLS significantly inhibited the Cg-induced neutrophil migration on peritoneal cavity of rats, it showed a even stronger inhibitory effect upon fMLP-induced neutrophil migration on peritoneal cavity. This demonstrates that FLS, besides blocking the synthesis or liberation of inflammation mediators such as PG, LT and cytokines can also block one of the migration steps or maybe some of the adhesion molecules involved. FLS also reduced tissue damage induced by acetic acid in rats, demonstrated by its ability to inhibit myeloperoxidase (MPO) activity. However, FLS was not capable of blocking cotton pellet induced granulation tissue formation, which is dependet on PG. FLS antinociceptive activity was observed in experimental pain models, such as the acetic acid-induced abdominal contractions and formalin test, both in mice. Nevertheless, FLS did not modify nociceptive response to thermic stimuli in the hot plate model. FLS antinociceptive effect does not depend on opioid or NO release, and equally is independent from adrenergic activity, though it seems to involve PDE and/or TNF-alfa and other cytokines inhibition. Anti-platelet activity of FLS, LCC and DRC was also studied and all of them showed in vitro platelet aggregation inhibition in platelet-rich human plasma, upon ADP, collagen, thrombin, arachidonic acid or adrenalin agonist addition. FLS, LCC and DRC anti-platelet effect was potentiated by PTX, a PDE inhibitor, but not by L-arginine or aspirin. In conclusion, FLS possess cytotoxic, anti-inflammatory, analgesic and anti-platelet activities. These effects seem to be mediated by the chalcones LCC e DRC, present in FLS.
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Nkosi, Themba Johan. "Antimicrobial activities of three medicinal plants against selected diarrheagenic pathogens." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1020759.
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Diarrhea is a global concern that the United Nations Children’s Fund (UNICEF) and the World Health Organization (WHO), have confirmed to be the second major cause of death in children under the age of five. Major bacterial pathogens that cause diarrhea include Escherichia coli, Salmonella species, Shigella species and Staphylococcus aureus. Antibiotic therapy is recommended depending on the severity and presentation of the disease; however, the appearance of antibiotic-resistant bacteria is an emerging global threat to the ability to treat these bacterial infections. This situation could be overcome by the discovery of new natural antibiotics. Plants have been a source of medicine for centuries and have been used to treat diseases including diarrhea. This makes plants a natural potential target to study for their antibiotic properties. The objective of this study was to determine the antibiotic properties of medicinal plants against known pathogens that cause bacterial diarrhea. Three medicinal plants, Cassia abbreviata, Kigelia africana, and Geranium incanum were investigated for their antimicrobial properties against these strains of microorganisms: American Type Culture Collection (ATTC) and Clinical Strains (CS). The plant materials were ground into powder, which was then dissolved in methanol, acetone and distilled water to extract the active compounds. The plant extracts were then used to (i) determine their antibiotic activity, (ii) determine the minimum inhibitory concentration (MICs), (iii) analyze the thin layer chromatography (TLC) fingerprints, and (iv) analyze the autobiography assay. The results obtained in this study met the aim and objectives of this study. The antimicrobial activities of the selected plants were obtained as discussed in Chapter 2 and 3. These results indicated that the traditional plants could be used as antimicrobials. In the screening assays, the test microorganisms were inhibited by the plant extracts, when they were subjected to plant extracts. This was performed on Mueller Hinton agar as sensitivity testing, which revealed clear zones of inhibition. The MIC values for each plant extract were established which ranged from 0.101 to 13.3 mg/dl. The TLC analysis revealed the spots which contained the active compounds which inhibited the bacterial growth. A bioautography assay was performed on the TLC plates, which exposed the exact spots containing the active compound inhibiting the bacteria. These results are clearly consistent with what former scientists have observed. Detailed explanations on the results are in Chapter 3 and 4 of this paper. It is important to note that all the procedures performed in this study were in vitro assays. Some effective in vitro assay activity may not always result in the same effective in vivo activity, because some active compounds may be metabolized and degraded into inactive metabolites. For this reason, the in vitro results obtained in this study, may not reflect the true effectiveness of the compounds in in vivo trials. It is therefore advised that future scientists should take a step further in analyzing the plant extracts through in vivo assays. Further testing and study on these plants at an advanced molecular level will be beneficial in the medical fields in the search for new antibiotics to treat infectious diseases. Purification and further analysis of their products can be helpful in the production of pure natural medicines. This will discover the active ingredients and compounds responsible for inhibition of the microorganisms. This will make the compounds potential candidates for a scientific validation and analysis for future scientists to bring a new dawn in the fight against infectious diseases.
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Khan, Fatima. "Effects of Leonotis leonorus aqueous extract on the isolated perfused rat heart." Thesis, University of the Western Cape, 2007. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_8367_1256897201.
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An aqueous extract prepared from the leaves and smaller stems of Leonotis leonorus was used to investigate the potential effects on certain cardiovascular parameters such as left ventricular systonic pressure, end-diastolic pressure, developed pressure, heart rate, cardiac work and coronary perfusion pressure in isolated rat hearts..."
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Mativandlela, Sannah Patience Nkami. "Antituberculosis activity of flavonoids Galenia africana L. var. africana." Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-10172009-095531/.
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Suleiman, Khairunisa Yahya. "The effects of a Kenyan antidiabetic plant on insulin homeostasis." Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/1055.
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The metabolic disorder diabetes; is a global epidemic affecting people in developed countries and increasingly in developing countries. In two decades time, 350 million people will be diabetic at the current rate of prevalence. In a preliminary study, insulin resistant rats were treated with Prunus Africana (plant A) for 28 days. Plasma samples obtained from P. africana treated rats had increased insulin levels compared to normal and untreated insulin resistant rats (Karachi, 2009). The treatment of insulin resistant rats with P. africana also showed increased glucose uptake in rat adipose tissue (Karachi, 2009), suggesting that P. africana had anti-diabetic properties. The aim of the study was to investigate the mechanism of the anti-diabetic properties of P africana extract. Increased insulin secretion was confirmed by the increased Cpeptide concentration in plasma samples of rats treated with P. africana. In order to explain the high insulin levels, several hypothesis’ were investigated: (1) P. africana may increase insulin secretion in β cells, hence the effect of P. africana on insulin secretion by INS-1 cells was investigated; (2) P. africana may increase insulin secretion by prolonging the half-life of glucagon like peptide-1 (GLP-1) by decreasing dipeptidyl peptidase IV (DPP IV) activity; the effect of P. africana on DPP IV activity was determined spectrophotometrically, (3) P. africana may increase the half-life of insulin in the plasma by decreasing the activity of insulin degrading enzyme (IDE); the effect of P. africana on IDE in rat muscle and spleen samples was investigated. To explain the increased glucose uptake in adipose tissue observed in the previous study two parameters were investigated: (1) increased GLUT4 expression in P. africana treated rats; the effect of P. africana treatment on the expression of glucose transporter 4 (GLUT4) was determined using real-time polymerase chain reaction (RT-PCR), (2) P. africana may increase glucose utilization; the effect of P. africana on glucose utilization was determined in 3T3-L1 cells. The plant extract did not significantly increase insulin secretion by INS-1 cells in the absence of glucose. P. africana decreased DPP IV activity in rat plasma when compared to the untreated insulin resistant rats and this could be a mechanism by which insulin secretion is increased during plant treatment. P. africana decreased IDE activity (however not significantly) when compared to the untreated insulin resistant The effects of a Kenyan antidiabetic plant on insulin homeostasis KY Suleiman VII rats. P. africana appeared to have no effect on GLUT4 expression. The plant appeared to increase glucose utilization in 3T3-L1 cells in the absence of insulin suggesting that P. africana may have insulin like activity. In summary, this study indicates that P. africana is indirectly involved in inhibiting DDPIV. This in turn can increase the half life of GLP-1, which in turn can enhance the secretion of insulin. P. africana increases glucose utilization although there was no evidence that the GLUT 4 transporter has a higher expression in the plant treated rats. Further studies should be conducted to investigate the expression of GLUT1 under the same conditons.
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董穎 and Ying Dong. "Antitumor effects and mechanism of actions of Chinese herbalmedicines: a purified coriolus versicolorpeptide and tetrandrine." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31213066.
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Okpako, Larry Commander. "Investigation of selected Nigerian medicinal plants as a source of new antimalarial agents. Isolation of phytochemicals from some Nigerian medicinal plants using chromatographic techniques and their evaluation for antiplasmodial activity." Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/6304.
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Malaria affects hundreds of millions of people worldwide and equally claims hundreds of thousands of lives each year. With the current spread of drug resistance to standard antimalarial drugs like chloroquine and the emergence of artemisinin-resistant parasites, new antimalarial drugs and formulations are urgently needed.
An ethnobotanical survey was carried out in this study in search of novel compounds with promising antiplasmodial activity. Using the ethnobotanical approach, a total of 61 plant species from 59 genera distributed in 34 plant families were found to be used traditionally for the treatment of malaria in Nigeria.
Biological evaluation of the plant¿s methanolic extracts was assessed using the parasite lactate dehydrogenase (pLDH) assay against the chloroquine-sensitive (3D7) and chloroquine-resistant (K1) strains of Plasmodium falciparum. A total of five (5) plant species showed more potent antiplasmodial activities against the malaria parasites. These are Acanthospermum hispidum, Cassia occidentalis, Kaempferia aethiopica Prosopis africana and Physalis angulata with MIC values ranging between 7.815µg/ml to 31.25µg/ml (3D7 strain) and 15.63µg/ml to 62.50µg/ml (K1 strain) against the malaria parasites, respectively. Two plants, Prosopis africana (Leguminosae-mimosoideae) and Physalis angulata (Solanaceae) were selected for further study.
The phytochemical investigation of the active chloroform extracts of P. africana and P. angulata yielded several compounds with three known alkaloids, namely, prosopinine (I), prosopine (II) and acetamide (III). Their structures were confirmed by MS, 1D and 2D NMR spectroscopy. Compounds I, II and III have moderate in vitro antiplasmodial activity against the malaria parasites. Both chloroquine and artemether were used as standard control.Association of Commonwealth Universities and the Commonwealth Scholarship Commission in the UK (Commonwealth Scholarship Reference Number: NGCS-2005-259).
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Dong, Ying. "Antitumor effects and mechanism of actions of Chinese herbal medicines : a purified coriolus versicolor peptide and tetrandrine /." Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19669860.
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Ezuruike, U. F. "Evaluation of herb-drug interactions in Nigeria with a focus on medicinal plants used in diabetes management." Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1465961/.
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Studies have shown an increasing use of herbal medicines alongside conventional drugs by patients in their disease management especially for chronic diseases, with the attendant risks of herb-drug interactions. In order to forestall this, adequate information about the pharmacological and toxicological profile of herbal medicines and how these would in turn affect the bioavailability of the co-administered drug is required. To evaluate potential herb-drug interactions that could occur in diabetes management in Nigeria- (a) An assessment of available data on the pharmacological and toxicological effects of plants used in diabetes management was conducted as a means of mapping those with identified potential risks for herb-drug interactions; (b) A field work study was carried out in different localities in Nigeria to identify potential pharmacokinetic interactions based on the prescription drugs and herbal medicines co-administered by diabetic patients; and (c) Experimental analysis of plant samples collected during the field work was done to assess their effects on known cell detoxification mechanisms and pharmacokinetic parameters. The results of the research have confirmed the continued use of a wide range of medicinal plants in diabetes management, many of which have not been thoroughly investigated. In addition, 50% of diabetic patients visiting healthcare facilities in Nigeria routinely manage their diabetes or existing co-morbidities with herbal medicines alongside prescription drugs. Even more worrying is the frequent use of unlabeled herbal preparations which would constitute a huge challenge in the proper identification of herb-drug interactions when they occur. Based on previously available data and the experimental results of this research, a number of these herbal medicines have been identified as having overlapping interactions with prescription drugs. There is therefore a need for better regulation of herbal medicine use alongside pharmacovigilance monitoring in Nigeria in order to forestall the occurrence of clinically relevant untoward herb-drug interactions.
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Sibanda, Thulani. "Assessment of antibacterial potentials of Garcinia Kola seed extracts and their interactions with antibiotics." Thesis, University of Fort Hare, 2007. http://hdl.handle.net/10353/71.
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The antibacterial potency of the extracts of the seed of Garcinia kola (bitter kola) was investigated in this study against a panel of referenced, environmental and clinical bacterial strains. The killing rates of the active extract as well as their potential for combination antibacterial therapy with standard antibiotics were also elucidated using standard procedures. The aqueous and acetone extracts of the seed were screened for activity against 27 bacterial isolates. The aqueous extract exhibited activity mainly against Gram positive organisms with Minimum inhibitory concentration (MIC) values ranging from 5 mgml-1 – 20 mgml-1, while the acetone extract showed activity against both Gram negative and Gram positive organisms with MIC values ranging from 10 mgml-1 - 0.156 mgml-1. The acetone extract also showed rapid bactericidal activity against Staphylococcus aureus ATCC 6538 with a 3.097 Log10 reduction in counts within 4 hours at 0.3125 mgml-1 and a 1.582 Log10 reduction against Proteus vulgaris CSIR 0030 at 5 mgml-1 after 1 hour. In addition, the aqueous, methanol and acetone extracts of the seeds also exhibited activity against four clinical strains of Staphylococcus isolated from wound sepsis specimens. The MIC values for the aqueous extract were 10 mgml-1 for all the isolates while the acetone and methanol extracts had lower values ranging from 0.3125 - 0.625 mgml-1. The acetone extract was strongly bactericidal against Staphylococcus aureus OKOH3 resulting in a 2.70 Log10 reduction in counts at 1.25 mgml-1 within 4 hours of exposure and a complete elimination of the organism after 8 hours. The bactericidal vi activity of the same extract against Staphylococcus aureus OKOH1 was weak, achieving only a 2.92 Log10 reduction in counts at 1.25 mgml-1 (4× MIC) in 24 hours. In the test for interactions between the acetone extract of the seeds and antibiotics, synergistic interactions were observed largely against Gram positive organisms using the FIC indices, (indices of 0.52 - 0.875) with combinations against Gram negatives yielding largely antagonistic interactions (indices of 2.0 to 5.0). Synergy (≥ 1000 times or ≥ 3 Log10 potentiation of the bactericidal activity) against both Gram negative and Gram positive organisms was detected by time kill assays mainly involving the antibiotics tetracycline, chloramphenicol, amoxycillin and penicillin G. Combinations involving erythromycin and ciprofloxacin consistently gave antagonistic or indifferent interactions. We conclude that the acetone extract of Garcinia kola seeds possess strong bactericidal activities against both Gram positive and Gram negative organisms and can be therapeutically useful in the treatment of bacterial infections including the problematic staphylococcal wound infections. In addition, the acetone extract can be a potential source of broad spectrum resistance modifying compounds that can potentially improve the performance of antibiotics in the treatment of drug resistant infections.
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Aboyade, Oluwaseyi Mayode. "Effect of processing on the efficacy and safety of Solanum Aculeastrum Dunal berries." Thesis, University of Fort Hare, 2009. http://hdl.handle.net/10353/d1001051.
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General Abstract There has been a steady increase in the use of medicinal plants in the last two decades in both developed and developing countries for prevention, management and treatment of diseases. This increase has been due to reasons such as ease of access, better cultural acceptability and compatibility, cost effectiveness and also the bid to “go natural”. Unfortunately, the notion that herbal medicines are relatively safe because they are natural has led to serious and potentially fatal consequences in phytotherapy. The lack of rigorous research to prove the effectiveness and safety of many medicinal plants is of great concern to the health care system. This thesis therefore addresses not just the efficacy, but also the safety of the extracts of the berry of Solanum aculeastrum - a medicinal plant used, among other things, for the treatment of breast cancer in the Eastern Cape Province of South Africa. Particular attention was paid to the possible effect of different processing methods of the berry extracts on inflammation, cytotoxicity, and toxicity. In studying the comparative effects of various processing methods, four different preparations of the extracts were investigated. These include fresh, dried, boiled fresh, and boiled dried berries. While the effect of processing on the anti-inflammatory properties of the extracts was not dose dependent, the percentage reduction in inflammation was highly significant and more prominent in both concentrations of the boiled fresh berries than the reference drug, indomethacin. Furthermore, the four extracts varied in their ability to act either centrally or peripherally in their effect on pain. Assessment of the analgesic response using the formalin test showed that, at both concentrations tested, none of the extracts inhibited the first phase of the formalin test. Furthermore, it was observed that boiling had differing results on the activity of the iii fresh and dried extracts. While boiling of the dried berries reduced pain in the rats, the opposite trend was observed with the boiled fresh berries. Results of the influence of processing of the berries on cytotoxicity indicated that the extracts are potent inhibitors of human breast, cervical and colonic carcinoma cells and the non-cancerous cells (both the actively dividing and confluent Chang liver cells). Although, in terms of relative potency, the fresh berries appeared to be the most active of the extracts, processing of the berries caused an increase in apoptotic cells and a subsequent decrease in the necrotic cells. The effect of processing on the safety of the berry of S. aculeastrum on the rats fed for 28 days was also investigated. The various doses (1, 10 and 25 mg/kg body weight) of all the four extracts did not alter the activity and the weight of the animals throughout the period of treatment. A reduction in organ to body weight ratio of the heart, kidney, liver and spleen was observed in all the extracts. Regarding the haematological parameters, different patterns of effect were observed between the extracts and within the treated doses. The observed alterations in the biochemical parameters by the various extract of Solanum aculeastrum berries at all the doses may have consequential effects on the normal functioning of these organs. In conclusion, this study has shown that there is some justification for the traditional use of the berries of Solanum aculeastrum in the treatment of inflammation related ailments and cancer. However, the medicinal use of the plant also poses considerable health risks. Investigation conducted into the plant’s safety revealed that the berry extracts were nephrotoxic, hepatotoxic, haematotoxic and at higher doses, fatal. Another concern with regard to the plant’s safety is the non-selectivity of its extracts in the inhibition of carcinoma, actively dividing and un-dividing cells. Assessment of the effect of the processing on the berry’s efficacy and safety as herbal iv remedy produced mixed results. On the one hand, processing seemed to improve the extract’s anti-inflammatory and analgesic activity, while reducing its cytotoxic potential. On the other hand, a reduction in the toxicity was observed on the processed extracts compared to the fresh ones. This may be an indication that processing has an overall beneficial effect on the medicinal properties of the plant and should thus be considered as a method of making the berries of Solanum aculeastrum safer for use as a herbal remedy.
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Shen, Yi. "Identification of novel anticancer drug candidates from Chinese medicinal herbs with DNA replication-initiation proteins as the targets /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?BICH%202008%20SHEN.
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Wang, Sheng Fang. "Neuroprotective effects and mechanisms of Traditional Chinese Medicinal compounds on experimental Parkinson disease models." Thesis, University of Macau, 2018. http://umaclib3.umac.mo/record=b3952179.
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Wu, Xia Xia. "The anti-inflammatory effects of two tanshinones isolated from Chinese herb Salvia miltiorrhiza Bunge." Thesis, University of Macau, 2018. http://umaclib3.umac.mo/record=b3952197.
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Purushothaman, Nair Vipin Devi Prasad. "Pharmaceutical analysis and drug interaction studies : African potato (Hypoxis hemerocallidea)." Thesis, Rhodes University, 2006. http://hdl.handle.net/10962/d1015802.
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In order for a medicinal product to produce a consistent and reliable therapeutic response, it is essential that the final composition of the product is invariable and that the active ingredient/s is/are present in appropriate, non-toxic amounts. However, due to the complexity involved in the standardization of natural products, quality control (QC) criteria and procedures for the registration and market approval of such products are conspicuously absent in most countries around the world. African Potato (AP) is of great medical interest and this particular plant has gained tremendous popularity following the endorsement by the South African Minister of Health as a remedy for HIV/ AIDS patients. Very little information has appeared in the literature to describe methods for the quantitative analysis of hypoxoside, an important component in AP. It has also been claimed that sterols and sterolins present in AP are responsible for its medicinal property but is yet to be proven scientifically. To-date, no QC methods have been reported for the simultaneous quantitative analysis of the combination, β- sitosterol (BSS)/ stigmasterol (STG)/ stigmastanol (STN), purported to be present in preparations containing AP. The effect of concomitant administration of AP and other herbal medicines on the safety and efficacy of conventional medicines has not yet been fully determined. Amongst the objectives of this study was to develop and validate quantitative analytical methods that are suitable for the assay and quality control of plant material, extracts and commercial formulations containing AP. Hypoxoside was isolated from AP and characterized for use as a reference standard for the quality control of AP products and a stability-indicating HPLC/ UV assay method for the quantitative determination of hypoxoside was developed. In addition, a quantitative capillary zone electrophoretic (CZE) method was developed to determine hypoxoside, specifically for its advantages over HPLC. A HPLC method was also developed and validated for the quantitative analysis of BSS, STG and STN in commercially available oral dosage forms containing AP material or extracts thereof. The antioxidant activity of an aqueous extract of lyophilized corms of AP along with hypoxoside and rooperol were investigated. In comparison with the AP extracts and also with hypoxoside, rooperol showed significant antioxidant activity. The capacity of AP, (extracts, formulations, hypoxoside and rooperol as well as sterols to inhibit in vitro metabolism of drug substrates by human cytochrome P450 (CYP) enzymes such as CYP 3A4, 3A5 and CYP19 were investigated. Samples were also assessed for their effect on drug transport proteins such as P-glycoprotein (P-gp). Various extracts of AP, AP formulations, stigmasterol and the norlignans, in particular the aglycone rooperol, exhibited inhibitory effects on CYP 3A4, 3A5 and CYP19 mediated metabolism.These results suggest that concurrent therapy with AP and other medicines, in particular antiretroviral drugs, can have important implications for safety and efficacy. Large discrepancies in marker content between AP products were found. Dissolution testing of AP products was investigated as a QC tool and the results also revealed inconsistencies between different AP products.
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Ncise, Wanga. "Environmental stress effects on the phytochemistry and bioactivity responses of a South African medicinal bulbous plant, Tulbaghia violacea Harvey (Alliaceae)." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2854.
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Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2018.Deteriorating living and environmental conditions have contributed to the increasing prevalence of diseases in plants and animals. In humans, accumulation of abnormally high levels of free radicals in the tissues has been implicated in many non-communicable diseases, such as diabetes, cancer, arthritis, ischemia, gastritis, obesity and asthma. Worldwide, there is recognition of need to improve plant and animal health. Tulbaghia violacea (Alliaceae) is a medicinal plant that is extensively harvested by traditional healers in the wild for its medicinal uses and if this practice continues, it may result in an unsolicited decline of the species in situ. Therefore, there is a need for cultivation of this species. Plant cultivation in a controlled environment for conservation purposes as well as the enhancement of yield and quality is gaining favour among farmers and consumers. The main aim of this study was to investigate the effects of altering the growing conditions by applying environmental stresses on the plant growth, antifungal and antioxidant activities of T. violacea, with the view of enhancing the future cultivation of this species for pharmaceutical companies, traditional healers and the horticulture industry. This study was divided into two parts, and the first part, which was further sub-divided into two separate preliminary experiments, is presented in chapter three. Simultaneous assessments of the effects of i) varied pH levels (pH 4, pH 6, pH 8) and ii) light intensity on plant growth, antioxidant-content and -capacity of extracts of T. violacea were carried out. The second part of the thesis consisted of a more detailed assessment of the above-mentioned independent variables and interactions thereof on plant growth, and antifungal activity of extracts of T. violacea. Results obtained from the first part of the study, showed that plants exposed to pH 6 showed a marked increase in plant height (from 25-37 cm) after 2 months of treatment although, generally, the variations of the different growth parameters among the pH treatments were not significant (p > 0.05). Antioxidant-contents and -capacity were not significantly different (p > 0.05) when pH treatments were compared. However, a high polyphenol content value (of 3 mg/g) occurred in leaves of plants exposed to pH 8. Overall, comparatively, there was no significant difference (p > 0.05) in antioxidant-content and -capacity when pH treatments. In the light experiment, decreasing light intensity led to the elongation of plant height. A higher mean shoot length of 34.6 cm was obtained under low light compared to normal light (26.5 cm) two months post-treatment. The results obtained in this study indicated that light had a significant affect (p < 0.05) on the vegetative growth of this species. In contrast, normal light intensity yielded higher antioxidant-content and -capacity. The polyphenol and flavanol content were fluctuating between the averages of 5.8 mg/g to 8.5 mg/g. Overall, there was a significant difference (p < 0.05) in the antioxidant-content and -capacity when low and normal light intensity treatments compared. In conclusion, both normal light intensity and at pH 8 induced better antioxidant results. In the second part of the study, chapter four, one-month old T. violacea plantlets were grown under two light intensities (low light and normal light) in a greenhouse and concurrently exposed to varying pH levels: pH 4, pH 6 and pH 8. Plants exposed to normal light received natural sunlight through the roof of the greenhouse, while low light intensity (40% reduction) was achieved using shade nets. Plants were drip irrigated with Nutrifeed fertilizer. Plant growth parameters such as height and fresh and dry weights were determined. Leaf samples were analysed for macro-and micro-nutrients contents. Antifungal tests were carried out on the plant extracts from the various treatments in an antifungal bioassay (minimum inhibitory concentration [MIC]). The experimental data collected were analysed using one and two-way analyses of variance (ANOVA), and Tukey HSD was used to separate the means at p < 0.05 level of significance. Varied effects of different pH levels (4, 6 and 8) and light intensities (low and normal) on plant height, and fresh and dry weights were recorded in the current study. A significant interactive (df, 2; F = 0.001; p < 0.001) effect between pH and light on fresh weight was observed. The results revealed that there was a significant difference (df, 2, 57; F = 12.63; p < 0.001) in dry weights with plants under normal light intensity and pH 4 treatment (8.285 ± 0.802 g) producing the highest dry weight. There was a significant interaction (df, 2; F = 6.4; p < 0.001) between pH and light intensity on plant dry weight. Extracts from plants grown under normal light intensity showed stronger antifungal activity at pH level 4, and MIC values ranged from 0.18 ± 0 to 0.375 ± 0.04 mg/ml at 6h and 1.5 ± 0 to 0.97 ± 0.18 mg/ml at 18h. In conclusion, this study demonstrated the interactive effects of pH and light intensity on the growth of T. violacea. These findings also confirmed that it is possible to enhance the cultivation of T. violacea under greenhouse conditions. Chapter 5 focused on the interactive effects of pH and watering regime on plant growth, nutrient uptake and antifungal activity of T. violacea plant extracts, grown hydroponically. The results showed that there were significant differences (p < 0.05) on plant growth parameters amongst the different watering regimes under normal light intensity. Broadly, two trends occurred in the results: firstly, more macro-nutrients were taken up by plants in the higher frequency watering intervals as opposed to higher tissue micronutrient nutrient values for plants grown under the lower light intensity conditions. The levels of N, P, K, Mg nutrient uptake differed significantly in plants (p < 0.001) among watering interval periods. On the other hand, plants simultaneously exposed to extended watering intervals of 21-day and low light intensity showed more bioactivity of the crude extracts against F. oxysporum in the MIC bioassay. Based on the current results, a combination of shorter watering interval and normal light intensity favoured plant growth and development, while plants grown under low light intensity with longer watering interval showed good bioactivity. Broadly, these results demonstrated that varying pH, light intensity, and watering regime can influence plant growth, secondary metabolite contents and antifungal activity of crude extracts of T. violacea. These findings will contribute to the current body of knowledge around cultivation of indigenous medicinal plants. The study will further benefit the conservation of medicinal plant initiatives, increased income of small-scale farmers and potentially promote indigenous knowledge by increasing the availability of South African medicinal plants.
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Liang, Ye Er. "Hormetic effects induced by heat-clearing herb extracts attenuate anticancer activity of chemotherapeutic agents." Thesis, University of Macau, 2017. http://umaclib3.umac.mo/record=b3690847.
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Tsang, Hing Yan. "Anti-tumour and anti-angiogenic effects of euxanthone." HKBU Institutional Repository, 2001. http://repository.hkbu.edu.hk/etd_ra/363.
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Njume, Collise. "Phytochemical analysis and bioactivity of selected South African medicinal plants on clinical isolates of Helicobacter pylori." Thesis, University of Fort Hare, 2011. http://hdl.handle.net/10353/449.
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Medicinal plants have been used as traditional medicine in the treatment of numerous human diseases for thousands of years in many parts of the world. In the developing world, especially in rural areas, herbal remedies continue to be a primary source of medicine. Scientifically, medicinal plants have proven to be an abundant source of biologically active compounds, many of which have already been formulated into useful therapeutic substances or have provided a basis for the development of new lead molecules for pharmaceuticals. Antibiotic resistance, undesireable side effects and expences associated with the use of combination therapy in the treatment of Helicobacter pylori infections have generated a considerable interest in the study of medicinal plants as potential sources of new drugs against this organism. The high complexicity of bioactive compounds accumulated in plants coupled with their broad antimicrobial activity may make it difficult for pathogenic organisms, including H. pylori to acquire resistance during treatment. This study therefore evaluates the antimicrobial potential of selected South African medicinal plants employed in the treatment of H. pylori-related infections, and the subsequent isolation of the plant active principles. An ethnobotanical survey of plants used in the treatment of H. pylori-related infections was conducted in the study area. Crude extracts of Combretum molle, Sclerocarya birrea, Garcinia kola, Alepidea amatymbica and 2 Strychnos species were screened against 30 clinical strains of H. pylori and 2 standard control strains (NCTC 11638 and ATCC 43526). In the preliminary stages of this study, ethyl acetate, acetone, ethanol, methanol and water extracts of the plants were tested against H. pylori by agar well diffusion and micro broth dilution methods. The plant crude extracts that exhibited anti-H. pylori activity with a iv percentage susceptibility of 50 percent and above were considered for the rate of kill assays and the most active crude extracts selected for bio-assay guided isolation of the active ingredient. Preliminary fractionation of the crude extract was achieved by thin layer chromatography (TLC) using different solvent combinations; hexane/diethylether (HDE), ethyl acetate/methanol/water (EMW) and chloroform/ethyl acetate/formic acid (CEF) in order to determine the most suitable combination for column chromatography (CC) and subsequent testing by indirect bioautography. The extract was then fractionated in a silica gel column using previously determined solvent combinations as eluent. Active fractions obtained from column chromatography separations were further fractionated and the compounds identified by gas chromatography/mass spectrometry (GC/MS) analysis. All the plants exhibited antimicrobial activity against H. pylori with zone of inhibition diameters ranging from 0 - 38 mm and minimum inhibitory concentration (MIC) values ranging from 0.06 - 5.0 mg/mL. The most active plant extracts were the acetone extract of C. molle with a percentage susceptibility of 87.1 percent, acetone and aqueous extracts of S. birrea (71 percent each) and the ethanolic extracts of G. kola (53.3 percent). Except for the aqueous extract, these extracts also exhibited a strong bactericidal activity against H. pylori at different concentrations. TLC analysis revealed the presence of 9 components in the acetone extract of S. birrea with the EMW solvent system as opposed to 5 and 8 with HDE and CEF respectively. Bioassay-guided isolation led to the identification of 52 compounds from the acetone extract of S. birrea with n-octacosane being the most abundant (41.68 percent). This was followed by pyrrolidine (38.91 percent), terpinen-4-ol (38.3 percent), n-eicosane (24.98 percent), cyclopentane (16.76 percent), n-triacontane (16.28 percent), aromadendrene (13.63 percent) and α-gujunene (8.77 percent). Terpinen-4-ol and pyrrolidine demonstrated strong antimicrobial activity against H. pylori at all concentrations tested. These results may serve as preliminary scientific validation of the ethnomedicinal uses of the above mentioned plants in the treatment of H. pylori-related infections in South Africa. Terpinen-4-ol and pyrrolidine could be considered for further evaluation as therapeutic or prophylactic agents in the treatment of H. pylori-related infections. However, further investigations would be necessary to determine their toxicological properties, in-vivo potencies and mechanism of action against H.pylori
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Belo, Cristóvão Ramiro. "Bétele (Piper Betle Linn): Análise de Metabolitos e acção sobre a Acetilcolinesterase." Dissertação, Faculdade de Farmácia da Universidade do Porto, 2009. http://hdl.handle.net/10216/20777.
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Mestrado em Controlo de QualidadeMSc in Quality Control
Piper betle L., conhecida como bétele, é uma espécie que se desenvolve largamente nos países do Sudeste Asiático, onde as suas folhas são económica e medicinalmente importantes. Para determinar o maior número possível de compostos voláteis e semivoláteis, as folhas foram sujeitas as diferentes processos de extracção, nomeadamente headspace - microextracção em fase sólida (HS-SPME), hidrodestilação e extracção por Soxhlet, e posteriormente analisadas por GC/MS, o que permitiu identificar 50 compostos, distribuídos por várias classes químicas, 23 dos quais foram descritos pela primeira vez. As diferentes técnicas permitiram a extracção de compostos distintos, sendo a HS-SPME aquela com que se obteve o perfil mais completo e com que se determinou maior teor de compostos. Dentro deste processo os melhores resultados foram obtidos utilizando a fibra revestida com divinilbenzeno/polidimetilsiloxano (DVB/PDMS). Considerando que a espécie é vulgarmente mascada, o seu extracto aquoso também foi analisado, tendo sido caracterizados apenas sete compostos, sendo o eugenol o composto principal. A composição em ácidos orgânicos deste extracto foi determinada por HPLC/UV e os ácidos oxálico, aconítico, cítrico, pirúvico, málico, chiquímico, acético e fumárico foram descritos pela primeira vez. O extracto aquoso também revelou capacidade para inibir a acetilcolinesterase de modo dependente da concentração.
Piper betle L., popularly known as “Paan”, is a species widely growing in South East Asia, where its leaves are economically and medicinally important. In order to screen the highest possible number of volatile and semi-volatile components, the leaves were subjected to headspace solid-phase microextraction (HS-SPME), hydrodistillation and Soxhlet extraction, prior to their analysis by GC/MS, which allowed the identification of 50 compounds, distributed by several chemical classes, 23 of them described for the first time. The different techniques lead to distinct compounds' extraction, with HS-SPME extracting highest amounts and providing the most complete profile. Within this procedure, best results were obtaine using Divinylbenzene/Polydimethylsiloxane (DVB/PDMS) fibre. Considering the use of the species as masticator, an aqueous extract was also analysed, in which only seven compounds were characterize, being eugenol the main one. The organic acids composition of this extract was determine by HPLC/UV and oxalic, aconitic, citric, pyruvic, malic, shikimic, acetic and fumaric acids are reported for the first time in this species. The aqueous extract also displayed AChE inhibitory capacity, in a concentration-dependent way.
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Belo, Cristóvão Ramiro. "Bétele (Piper Betle Linn): Análise de Metabolitos e acção sobre a Acetilcolinesterase." Master's thesis, Faculdade de Farmácia da Universidade do Porto, 2009. http://hdl.handle.net/10216/20777.
Full textAbstract:
Mestrado em Controlo de QualidadeMSc in Quality Control
Piper betle L., conhecida como bétele, é uma espécie que se desenvolve largamente nos países do Sudeste Asiático, onde as suas folhas são económica e medicinalmente importantes. Para determinar o maior número possível de compostos voláteis e semivoláteis, as folhas foram sujeitas as diferentes processos de extracção, nomeadamente headspace - microextracção em fase sólida (HS-SPME), hidrodestilação e extracção por Soxhlet, e posteriormente analisadas por GC/MS, o que permitiu identificar 50 compostos, distribuídos por várias classes químicas, 23 dos quais foram descritos pela primeira vez. As diferentes técnicas permitiram a extracção de compostos distintos, sendo a HS-SPME aquela com que se obteve o perfil mais completo e com que se determinou maior teor de compostos. Dentro deste processo os melhores resultados foram obtidos utilizando a fibra revestida com divinilbenzeno/polidimetilsiloxano (DVB/PDMS). Considerando que a espécie é vulgarmente mascada, o seu extracto aquoso também foi analisado, tendo sido caracterizados apenas sete compostos, sendo o eugenol o composto principal. A composição em ácidos orgânicos deste extracto foi determinada por HPLC/UV e os ácidos oxálico, aconítico, cítrico, pirúvico, málico, chiquímico, acético e fumárico foram descritos pela primeira vez. O extracto aquoso também revelou capacidade para inibir a acetilcolinesterase de modo dependente da concentração.
Piper betle L., popularly known as “Paan”, is a species widely growing in South East Asia, where its leaves are economically and medicinally important. In order to screen the highest possible number of volatile and semi-volatile components, the leaves were subjected to headspace solid-phase microextraction (HS-SPME), hydrodistillation and Soxhlet extraction, prior to their analysis by GC/MS, which allowed the identification of 50 compounds, distributed by several chemical classes, 23 of them described for the first time. The different techniques lead to distinct compounds' extraction, with HS-SPME extracting highest amounts and providing the most complete profile. Within this procedure, best results were obtaine using Divinylbenzene/Polydimethylsiloxane (DVB/PDMS) fibre. Considering the use of the species as masticator, an aqueous extract was also analysed, in which only seven compounds were characterize, being eugenol the main one. The organic acids composition of this extract was determine by HPLC/UV and oxalic, aconitic, citric, pyruvic, malic, shikimic, acetic and fumaric acids are reported for the first time in this species. The aqueous extract also displayed AChE inhibitory capacity, in a concentration-dependent way.
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Knowles, Cindy-Lee. "Synergistic effects of mixtures of the kresoxim-methyl fungicide and medicinal plants extracts in vitro and in vivo against Botrytis Cinerea." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
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The fungus Botrytis cinerea is an opportunistic pathogen on a wide variety of crops, causing disease known as grey mould through infections via wounds or dead plant parts. Synthetic fungicides for controlling this disease are fast becoming ineffective due to the development of resistance. This, coupled with consumers world wide becomng increasingly conscious of potential environment and health problems associated with the build up of toxic chemicals, (particularly in food products), have resulted in pressure to reduce the use of chemical pesticide volumes as well as its residues. An emerging alternative to random synthesis is the study and exploitation of naturally occurring products with fungicidal properties. There have been reports on the uses of synthetic fungicides for the control of plant pathogenic fungi. When utilized in two-way mixtures, such fungicides may maintain or enhance the level of control of a pathogen at reduced rates for both components utilized in combinations, or alone at normal rates. For this study it was hypothesize that the addition of plant extracts may enhance the antifungal efficacy of the synthetic strobilurin fungicide, kresoxim-methyl against Botrytis cinerea.
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Baatjies, Lucinda. "In vitro cytotoxic effects of selected Nigerian medicinal plant extracts on cancer cell lines." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1008191.
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Cancer is a disease that imposes a heavy burden on public health and poses a challenge to science. The World Health Organization estimates that 80 percent of people in developing countries of the world rely on traditional medicine for their primary health needs, and about 85 percent of traditional medicine involves the use of plant extracts. This is particularly true in Africa where a large percentage of the population depends upon medicinal plants for health care. Therefore, detailed screening and evaluation of bioactive substances for chemotherapeutic purposes of African plants are urgently warranted. Furthermore, this will serve to validate the efficacy and safety of African traditional medicine. The current study investigated the in vitro cytotoxic effects of 17 ethanolic extracts of the following 16 plants used in traditional anticancer medicine in Nigeria: Sapium ellipticum leaves, Sapium ellipticum stembark, Combretum paniculatum, Celosia trigyna, Pupalia lappacea, Justica extensa, Hedranthera barteri leaves, Alternanthera sessilis, Ethulia conyzoides leaves, Lannea nigritana stembark, Combretum zenkeri root, Combretum molle leaves, Adenanthera parvoniana, Lannea acida, Cyathula achyranthoides, Drymaria cordata, Cyathula prostrata, against HeLa cancer cells. Five of the most promising extracts (Sapium ellipticum leaves, Combretum paniculatum, Celosia trigyna, Drymaria cordata, Cyathula prostrata) were selected for further screening against HT29 and MCF-7 cancer cells. Of the five, the first two were investigated further based on their activities in the screening phase. The S. ellipticum leaf extract yielded IC50 values of 88.60 ± 0.03 and 93.03 ± 0.03 μg/ml against HeLa and MCF-7, respectively. The toxicity was also evaluated on normal cells and an IC50 of 77.66 μg/ml was obtained for peripheral blood mononuclear cells (PBMCs). The IC50 values for proliferating and confluent Chang liver cells were both >125 μg/ml. These results suggest that the extract may be selective for specific cell types. Bio-assay guided fractionation of the S. ellipticum ethanolic extract yielded two active fractions; chloroform and ethyl acetate. Two compounds isolated from the chloroform extract were screened against the three cancer cell lines and found to be inactive. Three compounds were isolated from the ethyl acetate fraction and revealed IC50 values < 62.5 and < 31 μg/ml against MCF-7. Unfortunately these two compounds soon lost activity before any further work could be done on them and work was continued with the crude extract.
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Wei, Wei. "Immunomodulating effects of natural polysaccharides isolated from astragali radix and dendrobii officinalis caulis /Wei Wei." HKBU Institutional Repository, 2016. https://repository.hkbu.edu.hk/etd_oa/350.
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Radix Astragali (the dried root of Astragalus membranaceous (Fisch) Bge.) and Dendrobii Officinalis Caulis (the dried stem of Dendrobium officinale Kimura et Migo) are two traditional Chinese tonic herbs. They are commonly used in the formula with other Chinese herbs for tonifying Qi, nourishing Yin, and treating various kinds of diseases, such as cancer, diabetes, inflammation, etc. The polysaccharides are considered the majority of the chemical components of decoction boiled from a formula including these two medicinal herbs. The previous study showed that the polysaccharides isolated from Radix Astragali (named RAP) and Dendrobii Officinalis Caulis (named DOP) have various pharmacological activities and most of their activities are closely related to their immunomodulating effects. Nonetheless, the exact mechanism of their immunomodulating effects, especially on macrophages is not known clearly. In the current study, we have conducted a comprehensive investigation of the bioactive properties and molecular mechanism of immunomodulating activities of DOP and RAP. We aimed to clarify the molecular immunomodulating mechanism of RAP on macrophages and the actual anti-fatigue activity of DOP in vivo. Results can be summarized as follows: RAP itself did not have any cytotoxic effect on mouse mammary carcinoma 4T1 cells, but it significantly enhanced cytotoxicity of the supernatant of RAW264.7cells on 4T1 cells. Furthermore, RAP enhanced the production of NO and cytokines in RAW264.7 cells, and significantly up-regulated gene expressions of TNF-α, IL-6, iNOS. All these bioactivities were blocked by the inhibitor of TLR4 (Toll-like receptor 4), suggesting that TLR4 is a receptor of RAP and mediates its immunomodulating activity. Further analyses demonstrated that RAP rapidly activated TLR4-related MAPKs, including phosphorylated ERK, phosphorylated JNK, and phosphorylated p38, and induced translocation of NF-κB as well as degradation of IκB-α. In addition, RAP induced higher gene expression of M1 marker, including iNOS, IL-6, TNF-a, CXCL10, compared with those of control group. RAP-induced BMDMs were polarized from M2 to M1 phenotypes. RAP stimulated RAW264.7 cells to express Notch1, Notch2, Jaddge1, Dll1 and SOCS3. Notch signaling pathway played an important role in the RAP-induced polarization of M1 phenotype macrophages. The RAP-induced BMDMs exhibited anti-cancer effect when they were transplanted with 4T1 cells together in vivo and it decreased tumor volume and tumor weight. DOP, the authentication marker of Dendrobii Officinalis Caulis, has immunomodulating activity in macrophage cell line RAW 264.7. DOP enhanced cell proliferation, TNF-α secretion, and phagocytosis in a dose-dependent manner. It induced the proliferation of lymphocytes alone and with mitogens. For further study the anti-fatigue effect of DOP in vivo, the weight-loaded swimming test was used, because it is an effective method for evaluation of the extent of fatigue. The results indicated that DOP treatment significantly increased the swimming endurance time, body weight, and food intake, compared to the positive control Rhodiola rosea extract. Moreover, the weight-loaded swimming test decreased the levels of glycogen in gastrocnemius muscle, SOD, GSH-Px in serum, and increased the levels of LDH, BUN, MDA, CK, TG, and LD in serum. All of these indicators of fatigue were inhibited to a certain extent by both DOP and Rhodiola rosea extract, and DOP's effects are stronger. Furthermore, DOP-feeding mice showed significantly increased cell variability of T lymphocytes and B lymphocytes, compared with control mice. In conclusion, RAP may induce cytokine production of RAW264.7 cells through TLR4-mediated activation of MAPKs and NF-κB. RAP-induced BMDMs were polarized from M2 to M1 phenotypes through Notch signaling pathway. The unique and dominant polysaccharide DOP is proven to be major, active polysaccharide markers of D. officinale, and showed stronger anti-fatigue activity than Rhodiola rosea extract. As such, DOP has promising potential for pharmaceutical development into anti-fatigue health product.
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Penduka, Dambudzo. "In-vitro anti-vibrio activities of crude extracts of Garcinia Kola seeds." Thesis, University of Fort Hare, 2011. http://hdl.handle.net/10353/405.
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The n-Hexane, dichloromethane, methanol and aqueous crude extracts of Garcinia kola (Heckel) seeds were screened for their anti-Vibrio activities against 50 Vibrio bacteria isolated from wastewater final effluents. The 50 isolates consisted of different Vibrio species namely V. fluvialis (14), V. vulnificus (12), V. parahaemolyticus (12), V. metschnikovii (3) and 9 others unidentified to the specie level. The n-Hexane, dichloromethane and methanol extracts had activities against 16 (32 percent) of the Vibrio isolates, while the aqueous extracts had activities against 12 (24 percent) all at a screening concentration of 10 mg/ml. The minimum inhibitory concentrations (MICs) were 0.313-0.625 mg/ml, 0.313-0.625 mg/ml, 0.313-2.5 mg/ml and 10 mg/ml for n-Hexane, dichloromethane, methanol and aqueous extracts respectively. Rate of kill studies were carried out against three different Vibrio species namely V. vulnificus (AL042), V. parahaemolyticus (AL049) and V. fluvialis ( AL040) using the n-Hexane, dichloromethane and methanol extracts at 1× to 4 × MICs and 2 hour exposure. About 96.3 percent, 82.2 percent, and 78.1 percent (V. fluvialis AL040); 92.6 percent, 87.8 percent and 68.9 percent (V. parahaemolyticus AL049); and 91.6 percent, 64.4 percent, 60 percent (V. vulnificus AL042) of the bacteria were killed by the crude n-Hexane, dichloromethane and methanol extracts respectively after 2 hour exposure time at 4× MIC. The patterns of activity were bacteriostatic, with the n-Hexane extracts being most effective in activity. We conclude that the Garcinia kola seeds have promise in the treatment and management of infections caused by Vibrio species.
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Qodi, Noluntu. "In Vitro tests for immunomodulatory effects of medicinal plants used in the treatment of Malaria in South Africa." Master's thesis, University of Cape Town, 2001. http://hdl.handle.net/11427/3454.
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Bibliography: leaves 78-80.Using the ethno-medicinal data approach, nine South African plants used traditionally in the treatment of malaria were collected and evaluated for cytotoxic and lymphocyte-proliferating effects. These included Acokanthera oppositofolia, Zanthoxylum capense, Glycyrrhiza glabra, Harpephyllum caffrum, Lippia javanica, Pentanisia prunneloides, Psidium guajava, Typha capensis and Cannabis sativa. The cytotoxic effect of the aqueous, methanol and dichloromethane extracts of these plants was evaluated in vitro in Rat-1 fibroblasts there was no observable difference in cytotoxic activity between cold-and hot-water extracts of all the plants investigated. Cell proliferation greater than 80% was observed for aqueous extracts of A. oppositofolia, H. caffrum, L. javanica, P. prunneloides, P. guajava and T. capensis which would suggest are considered safe for consumption. However, high cytotoxic effect was exhibited by dichloromethane extracts of Z. capense, L. javanica, C. sativa and P. guajava at 100 μg/ml. These findings suggest that dichloromethane extracted compounds that are not normally extractable by traditional methods.
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Shauli, Mathulo Mathabiso. "Histopathology induced by a medicinal plant indigenous to South Africa that has shown in vitro anti-microbial activity against drug resistant strains of Mycobacterium tuberculosis." Thesis, Nelson Mandela Metropolitan University, 2015. http://hdl.handle.net/10948/3990.
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Tuberculosis (TB) still remains a health problem globally with over a million new infections and a mortality rate of 1.5 million individuals annually (Hawn et al., 2014). The emerging multi-drug resistant (MDR) strains that accompany human immune deficiency virus (HIV) infection in high-incidence populations contribute significantly to the health burden of TB (Areeshi et al., 2014). The standard treatment that is advocated by the World Health Organization (WHO) for active tuberculosis includes long-term therapy that incorporates the use of isoniazid, rifampicin, pyrazinimide and ethambutol as front line drugs (WHO, 2013). Drug resistance against established treatment options for TB makes research into new forms of therapy an imperative in health care (Ntulela et al., 2009). South Africa is currently witnessing a high number of cases of drug-resistant TB. In some parts of the country, one in ten cases of TB is resistant to treatment. It is therefore essential to have new anti-tuberculosis agents, which can be readily and simply produced from some local source (Warner et al., 2014). A logical starting point for this research of new agents would be the herbal medicines which have been used for centuries in rural areas by local healers. Western developed countries have harvested ethno botanical knowledge and have produced drug therapies for conventional medicines for other ailments. The activity of extracts of the active plants and their properties still require study in animal models in order to assess their future as new anti-tuberculosis agents (Lall and Meyer, 1999). This study focuses on qualitative and quantitative experimental findings after the administration of a medicinal plant extract to animals. This will include daily observation of animals, recording of feed consumption, recording of animal weights, macroscopic examination of animals at necropsy, tissue harvesting, histological procedures and microscopy.
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Wei, Xi. "Effects of residual veterinary antibiotics on soil enzyme activity and plant growth." HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/830.
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Chadwick, Wayne. "Metabolic effects brought about by tricyclic antidepressants and the contribution of a medicinal plant in alleviating high fat diet induced insulin resistance in male wistar rats." Thesis, Nelson Mandela Metropolitan University, 2006. http://hdl.handle.net/10948/461.
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Type II diabetes is becoming a growing problem in developed countries worldwide. The median age for diagnosis was around sixty, but recent surveys have shown that the entire age distribution curve shifting left. The incidence of type II diabetes is thought to be parallel with the growing rate of obesity associated with an unhealthy western diet. Type II diabetes is an expensive disease to manage, it is for this reason that cheaper medication needs to be investigated in the form of traditional plants, such as Sutherlandia frutescens. Prescription medication, such as tricyclic antidepressants, may also increase body weight thereby playing a role in obesity. The cause of weight gain in such cases may go unrecognized or lead to cessation of the medication with or without the practitioner’s knowledge or approval. It is therefore necessary to investigate the causative agents responsible for the excessive weight gain. Drinking water containing extracts of S. frutescens or metformin was administered to two groups of eleven insulin resistant male Wistar rats. The insulin resistant control group received water without any medication. Rats were sacrificed after 8 weeks allowing for fasting blood glucose, insulin and tissue glycogen content determination. Glucose uptake was also determined using [3H] deoxyglucose. The effect of the medication and the diet on muscle post receptor insulin signaling proteins was determined through Western blots. Liver proteomics was also performed using 2-D electrophoresis. In a separate experiment 26 male Wistar rats were exposed to strepotozotocin toxin, 7 of these rats received intravenous insulin treatment, 7 rats received S. frutescens extract and 7 rats received a combination of both medications, the remaining 5 received no treatment and served as the control. Rats were sacrificed after 6 days allowing for fasting blood glucose, insulin and tissue glycogen content determination. Two groups of 14 male Wistar rats received amitriptyline or trimipramine (common tricyclic antidepressants) in their drinking water, the control group (30 rats) received water without any medication. The rats’ weight and food consumption was monitored throughout the trial and their oxygen consumption was also determined. Rats were sacrificed after 6 weeks or 14 weeks of medicinal compliance allowing for fasting blood glucose, insulin and tissue glycogen content determination. Glucose uptake was also determined using [3H] deoxyglucose. S. frutescens treatment normalized circulating serum insulin levels and significantly increased the rate of glucose clearance. Certain post receptor insulin signaling proteins were also significantly increased relative to the insulin resistant control group. 2-D electrophoresis identified the normalization of protein levels associated with the urea cycle. S. frutescens was also able to, independently; maintain normoglycaemic levels in the strepotozotocin treated group. The tricyclic antidepressants significantly increased blood glucose levels while significantly reducing tissue glycogen levels for both sacrifice periods. Serum insulin remained unchanged while a significant increase in insulin degradation and insulin degrading enzyme levels were found for both antidepressants. S. frutescens shows promise as a low cost antidiabetic medication for future use. Although the antidepressants did not promote weight gain, the increase in blood glucose levels may be cause for concern in patients with a pre-disposition toward developing diabetes.
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Hikuam, Willem Christoph. "Modulation of the redox status, phase 2 drug metabolizing enzymes and fumonisin-induced cancer promotion in rat liver by selected Southern African medicinal plants." Thesis, Cape Peninsula University of Technology, 2014. http://hdl.handle.net/20.500.11838/1524.
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Thesis submitted in fulfilment of the requirements for the degree
Doctor of Technology: Biomedical Technology
in the
Faculty of Health and Wellness Sciences
at the
Cape Peninsula University of Technology
2014According to the World Health Organization, cancer is the leading cause of death in the developed world, while it is the second leading cause of death in the developing world. In particular, liver cancer is the fifth most commonly diagnosed cancer in men, however, it is the second most frequent cause of death, responsible for an estimated 700,000 deaths annually. General limited access to health services, including treatment and the overall management of cancer in developing countries often contribute to the increased mortality rates when compared to developed countries. For centuries, medicinal plants have been used to prevent, and to a certain extent, treat cancer as a readily available and affordable alternative. In many instances, the curative or preventative claims still remain anecdotal. However, increasing evidence suggest that polyphenolic components of plants possess antioxidant activities, which are credited with curative/beneficial properties of medicinal plants. The curative properties could either be related to the primary compounds present in the plant itself, or the bio-activation products of plant components affecting hepatic drug metabolising and antioxidant enzymes systems related to carcinogen metabolism and maintaining oxidative homeostasis, respectively. Similarly, chronic consumption of medicinal plants could also result in hepatotoxicity, either caused by the primary plant components or bio-activation products. Due to these observations it is paramount to understand the mechanisms involved in the metabolism of plant components to critically assess beneficial versus potential harmful properties associated with chronic consumption. The focus of the current study was aimed at elucidating the bio-activity of four multipurpose indigenous plants to Southern Africa, i.e. Adansonia digitata, Agathosma betulina, Siphonochilus aethiopicus and Myrothamnus flabellifolius. Traditionally, A. digitata has been used as an immunostimulant, anti-inflammatory and analgesic agent, while also as an antipyretic agent in the treatment of diarrhoea and dysentery. Similarly, traditional medicinal uses of A. betulina include treatment cholera, haematuria, calculus, kidney diseases, as well as infections of the bladder, urethra, and prostate among others. S. aethiopicus was traditionally employed to treat infections associated with pains and fevers, whereas M. flabellifolius served as treatment of conditions ranging from respiratory ailments, backache, kidney problems, haemorrhoids, chest pain, and asthma. In the first part of this study, the polyphenolic contents and antioxidant capacities of the four plants were characterised. The emphasis was placed on using different solvents, namely water, ethanol and acetone for the extraction of the plant material and different methodologies to assess the antioxidant contents and -capacities of the various extracts as both these factors can influence the outcome. When considering the antioxidant contents, total polyphenols, flavanols, and flavonols of the different solvent extracts prepared from the four plants were determined, whereas three different assays were used for the antioxidant capacities, i.e. oxygen radical absorbance capacity (ORAC), trolox equivalent antioxidant capacity (TEAC) and ferric-reducing antioxidant power (FRAP) assays. The A. digitata acetone extract had the highest (7.121 mg gallic acid equivalent (GAE)/milligram (mg) soluble solids), whereas the water extract of the same plant had the lowest total phenolic content (0.008 mg GAE/mg soluble solids). In general, the acetone extracts demonstrated the highest total polyphenol, flavanol, and flavonol contents, followed by the ethanol extracts, with the water extracts having the lowest contents. M. flabellifolius was the only distinct deviation from this rule, where the water extract demonstrated the highest total polyphenol content. Considering antioxidant capacities, the acetone extracts provided the highest antioxidant capacities for all plants when assessed using the TEAC (8.56-32.68 milimole (mmole) trolox equivalent (TE)/mg soluble solids) and FRAP (5.69-37.39 mmole ascorbic acid equivalent/mg soluble solids) antioxidant assays, with the exception of M. flabellifolius where the water extract demonstrated the highest activity (22.73 mmole ascorbic acid equivalent/mg soluble solids). Antioxidant capacity determinations with TEAC and FRAP assays followed similar patterns, which were different from capacities determined by the ORAC (0.46-533.54 mmoleTE/mg of soluble solids) assay. Corroborating the antioxidant content findings, the acetone extracts also demonstrated the highest antioxidant capacities (140.41-533.54 mmoleTE/mg of soluble solids), followed by ethanol (94.62-151.29 mmoleTE/mg of soluble solids) and water (0.46-134.02 mmoleTE/mg of soluble solids). Only M. flabellifolius (TEAC and FRAP) and S. aethiopicus (FRAP) deviated from this trend. Correlations between the polyphenolic contents and antioxidant capacities indicated that acetone and ethanol were more effective in extracting polyphenolic compounds than water, while also providing extracts with superior antioxidant activities. Furthermore, ORAC assay was the antioxidant capacity determining assay of choice for the aqueous plant extracts, whereas the TEAC and FRAP assays were more suitable when determining the antioxidant capacities of the acetone and ethanol plant extracts. These results confirm the notion that no single assay can comprehensively determine the antioxidant activities of plant extracts and that a battery of assays should be used, as the various antioxidant capacity determination techniques use different substrates with different targets for measurement. The second part of this study comprised an in vivo experimental animal model to assess the potential toxicity, antioxidant status and modulation of the hepatic phase 2 drug metabolising enzymes following chronic consumption of the various plant extracts in male Fisher rats. Rats consumed aqueous extracts of the various plants (2% and 5% (w/v)) as the sole source of drinking fluid for 90 days, and the serum chemical pathology parameters for monitoring liver and kidney function conducted. These included alkaline phosphatase (ALP), aspartate transaminase (AST), alanine transaminase (ALT), total iron (Fe), and creatinine (CREA). Parameters for blood and hepatic redox status included total polyphenols, ORAC, reduced glutathione (GSH), oxidised glutathione (GSSG), their ratio (GSH:GSSG), conjugated dienes (CD) and thiobarbituric acid reactive substances (TBARS). Assessment of the phase 2 hepatic xenobiotic metabolising enzymes included glutathione S-transferase (GST) and activity in the cytosolic fraction and, UDP-glucuronosyltransferase (UDP-GT) activity in liver microsomes. When considering the liver and kidney function none of the plant extracts induced any significant toxicity, while 2% A. digitata significantly increased serum Fe. When considering the redox status, the whole blood and liver samples yielded similar results, with significant decreases in oxidised glutathione (GSSG) in rats consuming the 2% M. flabellifolius (82.76 mole/L) and 5% A. digitata (90.42 mole/L) with a resultant significant increase in the glutathione redox status (GSH:GSSG ratio of 5.69 and 5.64, respectively) when compared to rats consuming water (4.77). The GSH:GSSG ratio was also significantly increased by consumption of 2% A. betulina (8.45) and 5% S. aethiopicus (5.99). The consumption of all plant extracts, except 5% A. betulina and M. flabellifolius, significantly increased lipid peroxidation in the plasma CDs assay. These results indicated an increased antioxidant capacity in the liver with/without an associated reduced cellular oxidative stress status, which could be interpreted as a reduced susceptibility to oxidative damage. When considering the phase 2 hepatic enzymes, none of the plant extracts caused any significant changes in GST, GST or UDP-GT activities. The third part investigated the chemoprotective properties against cancer promotion in the liver utilising diethylnitrosamine (DEN) as cancer initiator and maize culture material of Fusarium verticillioides, containing the fumonisin B mycotoxins, as promoters in male Fischer rats. The rats consumed 2% (w/v) aqueous extracts of A. digitata, A. betulina, and S. aethiopicus over 28 days after cancer initiation and liver sections subjected to glutathione-S-transferase placental form positive GSTP+ staining and pre-cancerous liver foci categorised according to size. In addition, blood and liver analyses were done as described in the chronic feeding study above. Consumption of the A. digitata and, to a certain extent, S. aethiopicus extracts, altered the oxidative stress status in the liver as indicated by the increased lipid peroxidation, as determined by significantly increased liver CDs and the decreased GSH:GSSG ratio in the blood. This can be related to a subchronic toxicity due to the high total polyphenol intake as mentioned above. These underlying sub chronic toxic effects of A. digitata and S. aethiopicus are likely to be responsible for the observed inhibitory effect on the proliferation of GSTP+ minifoci in the liver. Hepatic phase 2 metabolising enzyme activities were not significantly altered by A. digitata and S. aethiopicus consumption, while GST activity was significantly increased by A. betulina treatment. Based on the findings of the current study, aqueous extracts of A. digitata, A. betulina, and S. aethiopicus may serve as hepatoprotectors with a potential to modulate liver carcinogenesis, specifically cancer promotion. To our knowledge, no other studies have attempted to describe the possible chemoprevention mechanisms of these indigenous medicinal plants. Assessments of phase 1 hepatic enzymes and other antioxidant enzymes are suggested for future studies to further describe biochemical and molecular mechanisms associated with consumption of these extracts. Additionally, identifying main compounds present in the plant extracts could culminate in development of drugs and novel nutraceuticals. It is also recommended that increasing concentrations of the plant extracts and/or the ethanol extracts to be used in future studies to better describe dose-responses of the different plants in liver carcinogenesis.
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Elgenaidi, Abdalla Ramadan. "Effects of Libyan traditional plants on the reproductive system of male and female rats." University of the Western cape, 2015. http://hdl.handle.net/11394/5412.
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Philosophiae Doctor - PhDIn different parts of the world, medicinal plants have demonstrated a lot of health benefits to mankind and remains an important source for the discovery of new bio-active compounds. Libya is a typical example of a country where medicinal plants are widely used. Plant extracts of five Libyan medicinal plants were used in this study to investigate their in vivo effects on spermatogenesis and steroidogenesis in male rats and on ovulation and fertility in female rats. The In vitro effects of these plant extracts were also investigated on TM3 Leydig cells and MCF 7 breast cancer cells. A phyto-chemical analysis of the five Libyan medicinal plants (flaxseed, black seeds, radish seed, date palm pollen and nutmeg) was done. The results showed that date palm pollen had a higher antioxidant activity than all of the above mentioned plants. In addition to this, Nigella sativa was observed to possess high flavonol content as well as high antioxidant activity. Male rats exposed to flaxseed, radish seeds and date palm pollen showed no significant alterations in body weight gain, whereas date palm pollen (240 mg/kg, p < 0.05) promoted an increase in body gain. This study also revealed a significant increase in the relative testicular weight of animals exposed to either flaxseed (300mg/kg) or date palm pollen (120mg/kg). In addition, the relative weights of the seminal vesicles of all treated groups showed significant increased values. The level of serum testosterone showed a significant increase after exposure to radish seed (80mg/kg) and a significant dose- dependent increase for date palm pollen when compared to control (P< 0.05). In contrast, flaxseed caused a dose-dependent significant (p <0.01) decrease in testosterone level at radish seed (300mg/Kg). All plant extracts caused a significant increase in sperm concentration. Sperm vitality significantly (p < 0.05) increased by radish seed (80mg/kg), flaxseed (300mg/kg) and date palm pollen (120, 240mg/kg) respectively. Total progressive motility improved significantly at flaxseed (300 mg/kg) (p < 0.001) as well as date palm pollen (p < 0.01). Histological examination of the cross sections of the testis showed clear presence of all stages of spermatogenesis in all the treated groups. Rat epididymides showed normal morphological appearance and their lumen were filled with spermatozoa. The diameter of seminiferous tubules in male rats exposed to date palm pollen (120 and 240 mg/kg) was significantly higher (p < 0.001). The heights of the germ cell epithelia within the eminiferous tubules were also significantly increased in all treated groups. Liver and renal functions tests showed a significant decrease in Alanine transaminase (ALT) and creatinine in all treated groups (p < 0.05), and this demonstrates the lack of cytotoxic effects of date palm pollen, radish seed and flaxseed on the rats. However, these plant extracts produced a non-significant (p > 0.05) increase in Aspartate transaminase (AST) levels. Besides this, superoxide dismutase activity (SOD) in testis was increased significantly by radish seed (160 mg/kg), flaxseed (200 mg/kg) and date palm pollen (120 mg/kg). There was also improved catalase activity in testis of male rats exposed to radish seed and date palm pollen. Regarding male sexual behavior, the time to reach the female and the mount frequency decreased significantly in male rats exposed to flaxseed (300 mg/kg) and date palm pollen (120 and 240 mg/kg; p > 0.05) thus, these plant extracts exhibit aphrodisiac properties. In addition, exposure of male rats to date palm pollen (120 mg/kg) produced a significant (p < 0.01) increase in the number of embryos in untreated female rats. In the female rats, the body weight gain was not affected (p > 0.05). However, the relative uterus weights exposed to nutmeg (200 mg/kg) and date palm pollen (120 and 240 mg/kg) were significantly decreased (p < 0.05). In addition, the relative weights of ovaries after treatment with nutmeg (400 mg/kg) and black seed (400 mg/kg) showed significantly increased values (p < 0.01). Serum FSH was significantly increased (p > 0.05 or 0.01) when the female rats have been exposed to black seed (200 mg/kg), nutmeg (200 mg/kg) or date palm pollen (120 mg/kg). The LH level significantly (p < 0.01) decreased following exposure to black seed (200 mg/kg), date palm pollen (120 mg/kg). On the other hand, serum LH concentration was significantly increased in female rats exposed nutmeg (400 mg/kg; p > 0.05). The creatinine activity in female rat serum in all treated groups was significantly decreased (p < 0.05). Whereas the higher dose of date palm pollen (240 mg/kg) caused only a non-significant decrease. ALT activity in serum of female rat exposed to either black seed (400 mg/kg) or date palm pollen (120 and 240 mg/kg) was shown to decrease significantly (p < 0.05). Histology of the reproductive organs, kidney and liver in the female rats showed no obvious alterations in any of the treated groups. In addition, the number of embryos in female rats significantly increased (p < 0.01; p < 0.001) following exposure of female rats to black seeds 400 and date palm pollen 240 mg/kg, respectively. Incubation of TM3 Leydig cells with radish seeds for 24, 48 or 72 hours caused a significant (p < 0.01) decrease in mitochondrial dehydrogenase activity. Besides that, date palm pollen and flaxseed increased the mitochondrial dehydrogenases activity of TM3 Leydig cells. In addition, higher concentration of date palm pollen, nutmeg and black seed were cytotoxic to MCF7 breast cells. In testis slices testosterone secretion in vitro was significantly increased by flaxseed (500 μg/ml; p > 0·05) and date palm pollen (500 μg/ml; p > 0·01). MCf-7 cells treated with BS 10-50 μg/ml black seed and nutmeg 10-50μg/ml significantly increased cell proliferation. However, the treatment with date palm pollen produced only a weak estrogenic effect, which resulted in a concentration dependent significant increase as observed between 50-1000 μg/ml date palm pollen. In conclusion, in this study, we observed that date palm pollen, radish seed and flaxseed increased libido as well as steroidogenesis and spermatogenesis, improved hepato and nephron-protective effects. In female rats, the plant extracts NM, BS and date palm pollen potentiated the production of gonadotropic hormones. In addition to this, at lower concentrations these medicinal plants promoted cell growth, whereas at higher concentrations they inhibited cell proliferation of MCF- 7 breast cancer cells. The anti-oxidant effects of these plant extracts have been implicated for the above mention effects.
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Tyavambiza, Caroline. "The antimicrobial and immunomodulatory effects of Cotyledon Orbiculata extracts." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2721.
Full textAbstract:
Thesis (MSc (Biomedical Technology))--Cape Peninsula University of Technology, 2018.The challenge of antimicrobial resistance has increased drastically over the years as more microorganisms are becoming resistant to the available conventional treatments. The burden of antimicrobial resistant infections is intensified by the increase in immunocompromising conditions such as HIV/AIDS and cancer. Due to this challenge, pharmaceutical companies, health sectors and researches are in search of new antimicrobial agents that can solve the problem at hand. Medicinal plants are a reliable source for drug discovery as it is estimated that 25% of modern medicine originated from plants. They have also been used traditionally as sources of medicine in the treatment of many human ailments. Plants can also be applied in the field of nanotechnology. Nanotechnology is a promising field in medicine as it has the potential to offer improved methods for disease diagnostics and therapeutics. The use of plants in nanotechnology brings about biologically friendly nanomaterials. Cotyledon orbiculata is one of the well-known and common plants of South Africa that is used in traditional medicinal practices. The nanotechnology applications as well as the antimicrobial and immunomodulatory effects of this plant were evaluated. The ability of C. orbiculata to synthesize silver nanoparticles was determined. Optimisation of silver nanoparticle synthesis using water extract of C. orbiculata was done at different conditions. The conditions evaluated include, reaction temperature (25 and 70°C), silver nitrate concentration (1 and 3mM), plant extract concentration (1.5, 3 and 6mg/ml) and reaction time. The synthesis of silver nanoparticles using this plant was successful. The optimal conditions for the synthesis of silver nanoparticles using C. orbiculata were 3mg/ml of the C. orbiculata extract, 3mM silver nitrate at a reaction temperature of 70°C for 2 hours. Under these conditions, spherical, crystalline nanoparticles with sizes of 20-40nm were produced. The antimicrobial and immunomodulatory properties of C. orbiculata extracts and silver nanoparticles were evaluated. Antimicrobial activity was evaluated against Staphylococcus aureus, Staphylococcus epidermidis, Methicillin resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Candida albicans, using the micro-dilution assay to determine the minimum inhibitory concentration (MIC). The results obtained revealed that all extracts of C. orbiculata have antimicrobial properties against all the microorganisms tested. The MICs of the extracts ranged from 3.13 to 50mg/ml and the MBC/MFC from 6.25 to >100mg/ml. The methanol extract exhibited better antimicrobial activity in comparison to the others extracts whereas the water extract had better antifungal properties. The chloroform extract showed the lowest activity in both antibacterial and antifungal studies. Silver nanoparticles also exhibited antimicrobial activity against all the microorganisms tested. It’s MICs against these microorganisms ranged from 5–80μg/ml and MBC/MFC from 20-160μg/ml. The silver nanoparticles were highly active than the water extract against both the bacteria and the fungi. Immunomodulatory effects of the plant extracts and silver nanoparticles were determined by evaluating cytokine production using the enzyme linked immunoassay (ELISA) assay. All the extracts and silver nanoparticles of C. orbiculata were found to have anti-inflammatory properties. The water extracts showed more anti-inflammatory activity against the cytokines than the other extracts. However the silver nanoparticles were more active than the water extract. The findings from this study confirmed that C. orbiculata have antimicrobial and immunomodulatory effects. This provided scientific evidence of the traditional use of this plant in the treatment of skin infections and inflammatory conditions.
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Owen, Josée. "The effects of nitrogen, harvest method and substrate on the growth and the medicinal compound concentration of hydroponically-grown sundew (Drosera adelae F. Muell.) /." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33435.
Full textAbstract:
Some species of sundew (Drosera spp.), harvested from the wild for use in homeopathic cold remedies, are now endangered. This research consisted of two experiments in hydroponic production of sundew. The first investigated the effects of four nitrogen (N) fertilization levels (0.0, 5.1, 25.5 or 51.0 mg/L added N) and three harvest methods (after two months, four months, and sequential harvest at two and four months) on the growth of Drosera adelae (F. Muell.). In addition, the effect of N on the production of a medicinal active ingredient in D. adelae was examined. The second experiment investigated effects of the same nitrogen treatments in combination with three substrates (long fiber sphagnum, peat or rockwool) on growth. The growth rate of D. adelae was greatest at low levels of nitrogen fertilization, and slowed after two months of growth. Plants that were sequentially harvested had the lowest growth rate among all the harvest method treatments. Young plants and plants that received little or no N fertilizer had a greater water concentration than the other plants. Substrate and N level interacted, but generally peat and rockwool produced greater yields than did sphagnum. The medicinal compound plumbagin and a similar but unidentified compound were detected in the leaf extracts of D. adelae. However, whether N fertilization influenced the concentration of these compounds remains inconclusive.
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Ajayi, Emmanuel Olusegun. "Interaction of terpenes and oxygenated terpenes with some drugs." Thesis, University of Fort Hare, 2012. http://hdl.handle.net/10353/418.
Full textAbstract:
SFME and HD for the extraction of essential oil in Lavandula officinalis in Alice have been reported. A total of 59 compounds were identified with the major compound being 1,8-cineole, an oxygenated monoterpene, with 46.89% and 44.84% yield obtained for HD and SFME respectively. Charge transfer (CT) complexes formed between α-pinene, 1,8-cineole and camphor as electron donors with iodine as the electron acceptor have been studied spectrophotometrically in methylene chloride solution. The Benesi- Hildebrand equation has been applied to estimate the formation constant (Kf) and molecular extinction coefficient (εCT). The value of Kf is the highest in camphor-I2 complex compared to the other two complexes. Antibacterial assessment was carried out on the various reagents, determining the MIC of individual reagents and in combination. The results show an improvement, on combination of the various reagents than when tested alone.
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Davison, Candice. "A biochemical study of the antidiabetic and anticogulant effects of Tulbaghia Violacea." Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/1523.
Full textAbstract:
Secondary metabolites derived from plants, especially those used by traditional healers, are at the forefront of new drug development in combating diseases such as cancer and diabetes. Garlic is employed in indigenous medicine all over the world for the treatment of a variety of diseases. Dietary garlic has been recognized for its beneficial health effects. In particular, garlic consumption has been correlated with (i) reduction of risk factors for cardiovascular diseases and cancer, (ii) stimulation of immune function, (iii) enhanced detoxification of foreign compounds, (iv) hepatoprotection, (v) antimicrobial effects, (vi) antioxidant effects, and most importantly (vii) its hypoglycemic and anticoagulant properties. Due to these beneficial properties, garlic and its closely related genera which includes Tulbaghia violacea, may be useful as coadjuvant therapy in the treatment of type 2 diabetes and some of its physiological complications. The aim of this study was to determine if T. violacea has antidiabetic and anticoagulant properties. This was performed in vitro using both aqueous and organic extracts of the roots, leaves and bulbs. An organic extract was able to improve glucose-stimulated insulin secretion (GSIS) in INS-1 pancreatic β-cells and glucose uptake in Chang liver cells. The BO extract had no effect on the glucose uptake in 3T3-L1 an adipose cell line and reduced glucose utilisation in C2C12, a skeletal muscle cell line. Some of the properties displayed by T. violacea in this study are consistent with those found in similar studies with garlic extracts. It was observed that the BO extract increased the membrane potential and Glut-2 expression in INS-1 cells cultured at hyperglycemic levels, however, at normoglycemic levels a reduction was observed. The oxygen consumption increased at both glycemic levels due to treatment with the BO extract. Platelets were exposed to the extracts to determine their effects upon platelet aggregation, adhesion and protein secretion. Since the BO extract displayed the highest potential at inhibiting platelet aggregation and adhesion. A rat model was used in ex vivo studies to determine if the extract exhibited the same effect in a physiological model. It was noted that the BO extract exhibited a higher degree of inhibition on platelet aggregation and adhesion than the positive control, aspirin. The BO extract reduced clotting times in the prothrombin time (PT) test, but prolonged the clotting time in the actived partial thromboplastin time (APTT) assay in the ex vivo model; however, it had no affect on these clotting assays in the in vitro model using human blood. The BO extract increased the D-dimer and Fibrinogen-C levels in the in vitro model, but had no effect on the D-dimer concentrations and lowered the Fibrinogen-C levels in the ex vivo model. The active compounds in the extract remain to be elucidated.
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Amare, Ayalew Mamed. "Mycoflora and mycotoxins of major cereal grains and antifungal effects of selected medical plants from Ethiopia /." Göttingen : Cuvillier, 2002. http://www.loc.gov/catdir/toc/fy0612/2006388754.html.
Full text
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Omodanisi, Elizabeth Ife. "Modulatory effects of Moringa oleifera extracts on Streptozotocin-induced diabetes in male Wistar rats." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2558.
Full textAbstract:
Thesis (DTech (Biomedical Technology))--Cape Peninsula University of Technology, 2017.Diabetes mellitus (DM) is characterized by deficiency in insulin resulting in hyperglycaemia with metabolic alterations in carbohydrate, lipid and protein. DM has been associated with increased formation of reactive oxygen species (ROS) and inflammatory mediators. Many drugs have been designed for its treatment and management; however, limitations persist in the use of anti-hyperglycemic medications due to numerous side effects, high cost, limited action and secondary failure rates. Moringa oleifera (MO) tree is distributed in the tropics and subtropics and has been found to be very nutritious with a variety of applications. This plant has been reported to possess antidiabetic, antioxidant and other medicinal properties which may be helpful in managing diabetes and its associated complications. This study investigated the antioxidant status, antidiabetic, antilipidemic, anti-inflammatory, anti-apoptotic properties and phytochemical constituents of the leaf extract of MO (250 mg/kg). Diabetes was induced in Wistar rats by a single intraperitoneal injection of streptozotocin (STZ) in buffered citrate (0.1, pH 4.5). Forty-eight Wistar rats were randomly divided into four (4) groups and treated for six weeks: group one- non-diabetic control (Control), group two- non-diabetic Moringa treated (Moringa), group three- diabetic control (Diabetic) and group four- diabetic Moringa treated (Diabetic + Moringa). Methanol, aqueous and petroleum ether extract of MO leaves were evaluated for its antioxidant and phytochemical contents. Assays for total antioxidant capacity such as trolox equivalence antioxidant capacity (TEAC), oxygen radical absorbance capacity (ORAC), ferric reducing antioxidant power (FRAP), flavonoids, flavonols and total polyphenols content were analysed. Other parameters analysed include glucose level; glycated haemoglobin level; hepatic biomarkers; endogenous antioxidants (SOD, CAT, GSH, GPx) in the liver; kidney and erythrocytes; inflammatory biomarkers in the serum, liver and kidney; high-density lipoprotein (HDL), low-density lipoprotein (LDL) and total cholesterol (TC) in serum. Assessment of apoptotic cell death biomarkers (caspase 3, caspase 9, BCL-2, NFKβ, p53) in the liver and kidney were performed. Histopathological analysis was conducted on the liver, kidney and pancreatic sections. In vitro results showed that aqueous and methanol extract of MO demonstrated a high antioxidant capacity, phenolic contents and revealed more chemical constituents than the petroleum ether extract. HPLC analysis of the leaf extract indicated the presence of flavonoids: quercetin, rutin and myricetin and phenolic acids. High levels of polyphenols, flavonols and alkaloids were reported in MO extracts. Treatment with MO in normal and diabetic rats daily for six weeks resulted in significant (p<0.05) decrease in glucose and glycated haemoglobin levels. Liver and kidney size which increased in diabetic rats, decreased significantly (p<0.05) after treatment with MO. Pancreas size showed significant (p<0.05) decrease in diabetic rats and increased significantly (p<0.05) after MO administration. Similarly, serum albumin level increased in non-diabetic and diabetic groups after MO treatment. Also, a significantly increased level of T-bilirubin in diabetic groups relative to normal control rats which reduced greatly after MO administration was observed. Serum lipid profile: LDL and TC levels were increased in rats exposed to STZ. HDL level decreased in diabetic rats when compared to normal control. The activities of MO extracts was shown to lower TC and LDL levels. HDL level also increased after MO administration. Similarly, lipid peroxidation (MDA) level significantly (p<0.05) decreased in the diabetic group following MO treatment. An observable improvement was seen in the antioxidant enzyme system. Activities of antioxidant enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and concentration of glutathione (GSH) were restored or increased in the homogenate of the liver, kidney, and erythrocytes, indicative of the protective effect of MO in diabetic and non-diabetic rats. The expression of cell death markers (caspase 3, caspase 9, BCL-2, NFKβ, p53) showed remarkable improvement after treatment with MO relative to the non-diabetic control. A significant (p<0.05) reduction in inflammatory cytokines (IL-1α, IL-6, IL-12, IL-18, TNF-α) and (chemokine MCP-1 concentrations) were observed in the serum, liver, and kidney of non-diabetic and diabetic treated groups. Histopathological sections of the liver, kidney and pancreas of diabetic rats revealed severe damage which showed significant improvements after MO treatment. Liver, kidney and pancreatic histological sections revealed the protective effect of MO in both non-diabetic and diabetic rats. MO exerted modulatory effects in STZ-induced diabetes by its antidiabetic, hypoglycemic, antioxidant, anti-inflammatory, anti-apoptotic and anti-lipidemic activities and offered protective effects against diabetic-induced nephrotoxicity and hepatotoxicity, but equally improved antioxidant status. The study concluded that MO could play a significant role in the early treatment and management of diabetes that pharmaceutical industry should consider it in the future as a possible therapeutic agent.
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Jin, Jing, and 金晶. "Proteomic profiling of mycelial extract derived from coriolus versicolor and analysis of their anti-tumor effects in human leukemiccells HL-60." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B41897110.
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45
"Study on the liver protective effects of Schisandra chinensis." 1999. http://library.cuhk.edu.hk/record=b5889971.
Full textAbstract:
by King Yeung Wong.Thesis (M.Phil.)--Chinese University of Hong Kong, 1999.
Includes bibliographical references (leaves 143-148).
Abstracts in English and Chinese.
Title Page --- p.i
Acknowledgement --- p.ii
List of Abbreviations --- p.iii
Table of contents --- p.v
Abstract --- p.viii
Chapter 1 --- Introduction --- p.1
Chapter 1.1 --- Liver diseases --- p.1
Chapter 1.2 --- Current treatments of liver diseases --- p.3
Chapter 1.3 --- Schizandrae --- p.5
Chapter 1.3.1 --- Chemistry of Schizandrae (Wuweizi) --- p.6
Chapter 1.3.2 --- Pharmacology of Wuweizi --- p.8
Chapter 1.3.2.1 --- Hepato-protective effect of Wuweizi --- p.9
Chapter 1.3.3 --- Toxicology and side-effects of Wuweizi --- p.11
Chapter 1.4 --- Carbon tetrachloride (CC14) intoxication --- p.12
Chapter 1.5 --- Hepatic drug metabolism: essential factors --- p.13
Chapter 1.6 --- Aim --- p.14
Chapter 2 --- Phase I metabolism --- p.15
Chapter 2.1 --- Introduction --- p.15
Chapter 2.2 --- Materials and Methods --- p.18
Chapter 2.2.1 --- Animals --- p.18
Chapter 2.2.2 --- Chemicals --- p.18
Chapter 2.2.3 --- Instruments --- p.19
Chapter 2.2.4 --- Preparation of Schizandra seed extract --- p.19
Chapter 2.2.5 --- Animal model of liver damages --- p.20
Chapter 2.2.6 --- Evaluation of protective effect of Schizandra extract --- p.22
Chapter 2.2.7 --- Evaluation of healing effect of Schizandra extract --- p.24
Chapter 2.2.8 --- Extraction of antipyrine from blood and urine --- p.26
Chapter 2.2.9 --- TLC method for quantitative analysis of antipyrine --- p.26
Chapter 2.2.10 --- Analysis of pharmacokinetic parameters of antipyrine --- p.27
Chapter 2.2.11 --- Statistical analysis --- p.28
Chapter 2.3 --- Results --- p.30
Chapter 2.3.1 --- Effect of CCI4 and Schizandra seed extract on antipyrine metabolism --- p.30
Chapter 2.4 --- Discussion --- p.41
Chapter 3 --- Phase II metabolism --- p.44
Chapter 3.1 --- Introduction --- p.44
Chapter 3.2 --- Materials and Methods --- p.46
Chapter 3.2.1 --- Chemicals --- p.46
Chapter 3.2.2 --- Preparation of Schizandra extract --- p.46
Chapter 3.2.3 --- Preparation of Salicylamide solution (for injection) --- p.47
Chapter 3.2.4 --- Preparation of 2，4-dinitrophenylhydrazine solution --- p.47
Chapter 3.2.5 --- Animal groups --- p.47
Chapter 3.2.6 --- Animal model of liver damage --- p.48
Chapter 3.2.7 --- Evaluation of the hepato-protective effect of Schizandra extract --- p.49
Chapter 3.2.8 --- Determination of serum glutamate pyruvate transaminase (SGPT/ALT) and serum glutamate oxaloacetate transaminase (SGOT/AST) --- p.50
Chapter 3.2.9 --- Salicylamide adminstration and plasma collection --- p.51
Chapter 3.2.10 --- Procession of plasma and urine samples --- p.52
Chapter 3.2.11 --- HPLC Analysis --- p.54
Chapter 3.2.12 --- Preparation of liver microsomes --- p.55
Chapter 3.2.13 --- Determination of cytochrome P450 --- p.56
Chapter 3.2.14 --- Determination of protein content of the liver microsomes --- p.57
Chapter 3.2.15 --- Data Analysis --- p.58
Chapter 3.2.16 --- Statistical Analysis --- p.58
Chapter 3.3 --- Results --- p.60
Chapter 3.3.1 --- Liver enzyme levels --- p.60
Chapter 3.3.2 --- Phase II metabolism profile of salicylamide --- p.61
Chapter 3.3.3 --- Cytochrome P450 content of liver --- p.64
Chapter 3.4 --- Discussion --- p.65
Chapter 3.4.1 --- Liver enzyme assay --- p.65
Chapter 3.4.2 --- Cytochrome P450 activity --- p.67
Chapter 3.4.3 --- Hepatic metabolism of salicylamide --- p.68
Chapter 3.4.4 --- Effect of CC14 intoxication on Phase II metabolism --- p.71
Chapter 3.4.5 --- Wuweizi actions on Phase II metabolism --- p.73
Chapter 4 --- Protein binding --- p.102
Chapter 4.1 --- Introduction --- p.102
Chapter 4.2 --- Materials and Methods --- p.104
Chapter 4.2.1 --- Chemicals --- p.104
Chapter 4.2.2 --- Instruments --- p.105
Chapter 4.2.3 --- Preparation of Warfarin sodium solution --- p.105
Chapter 4.2.4 --- Animal groups --- p.106
Chapter 4.2.5 --- Equilibrium dialysis --- p.106
Chapter 4.2.5.1 --- Equilibration time --- p.106
Chapter 4.2.5.2 --- Equilibrium dialysis of different warfarin concentration --- p.107
Chapter 4.2.6 --- High performance liquid chromatography analysis of warfarin --- p.108
Chapter 4.2.7 --- Calibration curve --- p.109
Chapter 4.3 --- Results --- p.111
Chapter 4.3.1 --- Equilibriation time --- p.111
Chapter 4.3.2 --- Calibration curve --- p.111
Chapter 4.3.3 --- Free concentration of warfarin --- p.112
Chapter 4.4 --- Discussion --- p.114
Chapter 4.4.1 --- Effect of CCl4 intoxication on free percentage of warfarin --- p.114
Chapter 4.4.2 --- Effcct of wuweizi cxtract on free percentage of warfarin --- p.115
Chapter 4.4.2.1 --- Depletion of plasma albumin concentration --- p.116
Chapter 4.4.2.2 --- Displacement of warfarin by WWZ extract --- p.117
Chapter 4.4.3 --- Concentration dependent protein binding --- p.118
Chapter 5 --- Hepatic blood flow --- p.124
Chapter 5.1 --- Introduction --- p.124
Chapter 5.2 --- Materials and Methods --- p.126
Chapter 5.2.1 --- Chemicals....: --- p.126
Chapter 5.2.2 --- Instruments --- p.126
Chapter 5.2.3 --- Preparation of indocyanine green (ICG) solution --- p.126
Chapter 5.2.4 --- Preparation of Schizandra seed extract --- p.127
Chapter 5.2.5 --- Animals groups --- p.127
Chapter 5.2.6 --- Animal model of liver damage --- p.128
Chapter 5.2.7 --- Evaluation of hepato-protective effect of Schizandra extract --- p.129
Chapter 5.2.8 --- Evaluation of healing effect of Schizandra extract --- p.129
Chapter 5.2.9 --- Quantitative analysis of ICG in plasma by UV spectroscopy --- p.130
Chapter 5.2.10 --- Analysis of pharmacokinetic parameters of ICG --- p.131
Chapter 5.2.11 --- Statistical analysis --- p.132
Chapter 5.3 --- Results --- p.133
Chapter 5.4 --- Discussion --- p.135
Chapter 5.4.1 --- Effect of CCl4 intoxication on hepatic blood flow --- p.135
Chapter 5.4.2 --- Effect of WWZ pretreatment on hepatic blood flow --- p.135
Chapter 5.4.3 --- Effect of WWZ healing on hepatic blood flow --- p.136
Chapter 6 --- General conclusion --- p.139
Significance of the study --- p.141
References --- p.143
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Dangarembizi, Rachael. "Effects of crude leaf extracts of Ficus thonningii on growth, gastrointestinal morphometrry and clinical biochemistry of suckling Sprague Dawley rats." Thesis, 2014.
Find full textAbstract:
Ficus thonningii is a nutraceutical that is extensively used in ethnomedicine. Nursing mothers
use F. thonningii leaves as nutritional and medicinal supplements and are at risk of exposing
their infants to its constituent phytochemicals. The exposure of the sensitive neonatal
gastrointestinal tract (GIT) to these phytochemicals can result in irreversible changes in
growth and development. The objectives of this study were to determine the effects of crude
F. thonningii extracts on; growth, morphology and morphometry of the abdominal viscera
and clinical biochemistry of neonatal rats.
Forty, suckling Sprague Dawley rats of either sex were randomly divided into 5 groups. Each
group was orally gavaged once daily with either low (50 mg/kg b.w) or high (500 mg/kg b.w)
doses of aqueous or methanolic extracts of F. thonningii, for 7 days. The control rats received
distilled water. The pups were euthanased and tissues were collected and weighed. Samples
of the liver, caecum and proximal small intestine were preserved and processed for histology.
Plasma biochemical parameters were analysed colorimetrically. Data was presented as means
+ SD.
F. thonningii extracts exhibited trophic effects on the stomach and ceacal mucosa of rats but
had no significant growth-promoting effects on the small intestine and visceral organs.
Histological analysis of the intestine, liver and caeca revealed no mucosal damage. Clinical
chemistry parameters were not abnormally altered. There was a significant decrease (p<0.05,
ANOVA) in the plasma concentrations of basal (non-fasting) glucose in the pups on the high
methanolic extracts. However, the triglyceride and cholesterol levels were unaltered by the
treatments.
The findings suggest that F. thonningii extracts exhibit trophic effects on the mucosal layers
of the stomach and caecum. F. thonningii extracts also possess glucose-lowering activity. At
low doses, F. thonningii extracts can be safely used without the risk of any disruption in the
structural integrity of the neonatal rat GIT and function of the liver and kidneys.
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"In vitro and in vivo studies on the wound healing effects of Chinese medicinal herbs." 2007. http://library.cuhk.edu.hk/record=b5893193.
Full textAbstract:
Law, Wai Tak.Thesis (M.Phil.)--Chinese University of Hong Kong, 2007.
Includes bibliographical references (leaves 107-123).
Abstracts in English and Chinese.
Abstract --- p.i
摘要 --- p.iv
Acknowledgements --- p.vi
Publications --- p.viii
Table of Contents --- p.ix
Chapter Chapter 1 --- Introduction
Chapter 1.1 --- Wound healing --- p.1
Chapter 1.1.1 --- Physiology of wound healing --- p.1
Chapter 1.1.2 --- Three phases of wound healing --- p.3
Chapter 1.1.3 --- Angiogenesis in wound healing --- p.10
Chapter 1.2 --- Delayed wound healing --- p.11
Chapter 1.2.1 --- Chronic ulcers --- p.11
Chapter 1.2.2 --- Examples of ulcers --- p.12
Chapter 1.3 --- Traditional Chinese medicine (TCM) --- p.16
Chapter 1.3.1 --- Principles of TCM --- p.16
Chapter 1.3.2 --- TCM and chronic ulcers --- p.16
Chapter 1.4 --- Objectives of study --- p.19
Chapter Chapter 2 --- Materials and Methods --- p.21
Chapter 2.1 --- Selection of traditional Chinese herbs --- p.21
Chapter 2.2 --- Authentication of TCM --- p.22
Chapter 2.3 --- Preparation of TCM --- p.23
Chapter 2.4 --- In vitro studies on the effects of TCM on wound healing --- p.23
Chapter 2.4.1 --- Angiogenesis study by using human umbilical vein endothelial cell (HUVEC) --- p.25
Chapter 2.4.2 --- Granulation study by using human fibroblast cell line (CRL) --- p.32
Chapter 2.4.3 --- Preparation of cell culture conditions --- p.35
Chapter 2.5 --- In vivo study on the effects of TCM on wound healing by using diabetic mice --- p.38
Chapter 2.5.1 --- Diabetic mice model --- p.38
Chapter 2.5.2 --- Diabetic mice wound induction --- p.41
Chapter 2.5.3 --- "Measurement of body weight, blood glucose level and ulcer area" --- p.43
Chapter Chapter 3 --- Results
Chapter 3.1 --- The percentage yield of each herbs --- p.48
Chapter 3.2 --- pH value of all the effective treatment concentration --- p.49
Chapter 3.3 --- Selection of traditional Chinese herbs --- p.53
Chapter 3.4 --- Effect of selected TCM on the proliferation of HUVEC --- p.55
Chapter 3.5 --- Effect of selected TCM on the migration of HUVEC --- p.61
Chapter 3.6 --- Effect of selected TCM on the proliferation of CRL --- p.63
Chapter 3.7 --- "Effect of Radix Rehmanniae (selected TCM) on the change in body weight, blood glucose level and ulcer area" --- p.66
Chapter Chapter 4 --- Discussions --- p.75
Chapter Chapter 5 --- How does my study contribute towards the modernisation of Chinese medicine? --- p.100
References --- p.107
Appendix --- p.124
48
Street, Renée Anne. "Heavy metals in South African medicinal plants." Thesis, 2008. http://hdl.handle.net/10413/801.
Full textAbstract:
Plants are able to take up and accumulate certain environmental contaminants such as heavy metals. When the plants are ingested by man, these contaminants are transferred along the food chain. Due to the poorly regulated medicinal plant trade in South Africa, many opportunities exist for heavy metal contamination of medicinal plants namely contaminated harvest sites as well as poor drying, processing, storage, transport and manufacturing conditions. The concentrations of five heavy metals (As, Cd, Co, Ni, Pb) and six microelements (B, Cu, Fe, Mn, Mo, Zn) were determined in some commonly used South African medicinal plants obtained from street markets. Elemental content was determined using inductively coupled plasma optical emission spectrophotometry (ICP-OES). Some of the medicinal plant samples investigated contained As and Cd at levels exceeding the World Health Organization limits of 1 and 0.3 mg kg-1 respectively. Lead and Ni were detected in all the samples. Elevated Fe and Mn levels were recorded in certain plant species. The results revealed multiple metal contamination in some medicinal plant parts sold in local markets and is thus grounds for concern. The effects of Cd application on growth parameters of some medicinal plant species belonging to the Hyacinthaceae (Albuca setosa, Eucomis autumnalis, Eucomis humilis, Merwilla plumbea) gave insight into heavy metal accumulation and distribution in these species. Application of Cd at 5 mg l-1 over a 12 week period reduced growth in A. setosa. The medicinally used A. setosa bulbs accumulated 37 mg kg-1 Cd after 12 weeks. Cadmium application at 2 mg l-1 over a six week period had no effect on growth parameters of E. autumnalis or E. humilis. However, a substantial difference in total Cd accumulation was detected in the plants (40.2 and 15.3 mg kg-1 respectively). Cadmium application at 2 mg l-1 significantly reduced the fresh weight of leaves, bulbs and roots of M. plumbea. Although most of the Cd was stored in the roots, the medicinally used bulbs accumulated up to 11.6 mg kg-1 when applied at 10 mg l-1. The antagonistic effect between Cd and Zn treatments and their effect on micronutrient distribution in M. plumbea were investigated. Five treatments were evaluated: (1) Hoagland’s nutrient solution (HS) (control) (2) HS + Cd 2 mg l-1 (single) (3) HS + Cd 2 mg l-1 + Zn 50 mg l-1 (combination) (4) HS + Cd 2 mg l-1 + Zn 100 mg l-1 (combination) (5) HS + Cd 2 mg l-1 + Zn 150 mg l-1 (combination). Cadmium readily accumulated in leaves, bulbs and roots of M. plumbea when supplied at 2 mg l-1. Zinc at 50 mg l-1 led to increased Cd accumulation. However, further increases in Zn concentration showed an antagonistic effect of Zn on Cd uptake and accumulation. Thus, increasing Zn levels in soils may be favourable for reducing toxic Cd accumulation in M. plumbea plants. Boron was not significantly affected by the addition of Cd to the media. However, with an increase in Zn, leaf B content increased while the B content in the bulbs and roots decreased. Copper and Mo levels were not significantly affected by treatments with Cd or Cd/Zn combinations. Compared to the control, Cd and Cd/Zn applications caused an increase in Mn content in leaves, bulbs and roots. Iron levels of M. plumbea were not significantly affected by Cd in the media. However, with an increase of Zn in the Cd-containing media, Fe content in the leaves, bulbs and roots increased. Tulbaghia violacea is one of the few medicinal plants that is also frequently used as a leafy vegetable. Application of Cd at 2 and 5 mg l-1 to T. violacea of varying sizes (small 8 - 10 g, medium 16 - 20 g, large 80 – 95 g) elicited a difference in growth response, Cd accumulation and micronutrient distribution. Leaf length and fresh weight of leaves of the medium-size plants decreased with application of Cd at 2 mg l-1 whilst 5 mg l-1 Cd significantly decreased the number of leaves in small-sized plants. Small plants accumulated more Cd in the leaves than medium- or large-sized plants. Application of Cd at 2 mg l-1 and 5 mg l-1 lowered the leaf Cu, Fe, Mo and Zn contents in small- and medium-size plants. This study indicated that T. violacea has the ability to accumulate Cd. In addition, plant size plays an important role with regards to Cd accumulation and elemental distribution. The effect of various nutrient applications (10%, 50% and 100% Hoagland’s nutrient solutions (HS); and HS deficient in N, P or K) on growth parameters and micronutrient distribution in Dioscorea dregeana were investigated. Irrigating plants with 50% HS resulted in better growth performance, whereas a deficiency of either N, P or K negatively affected seedling growth. Plants grown in 10% HS contained higher total B, Fe and Mo levels compared to seedlings grown in 50% and 100% HS. Compared to the control, P deficiency resulted in a Fe increase in the leaves, tuber and roots while a lack of P and K significantly increased total Mn content in D. dregeana. The effect of excess Zn (100, 200 and 300 mg l-1) on growth performance, chlorophyll content and microelemental distribution on Dioscorea sylvatica was investigated. Growth parameters showed a significant decrease when supplied with Zn at 100 mg l-1. Zinc phytotoxicity was evident by the reduction in chlorophyll content. Highest Zn concentrations were detected in the roots. Certain micronutrients appear to be redistributed due to Zn toxicity. The effect of microelements (Cu, Zn) and heavy metals (Cd, Pb, Hg) on germination and seedling development of Bowiea volubilis, Eucomis autumnalis and Merwilla plumbea was investigated. Copper and Zn applied at 1 mg l.1 significantly reduced the percentage germination of E. autumnalis. Low concentrations (. 1 mg l.1) of Cu and Zn negatively affected the root growth of all three species. Mercury concentrations of 0.5 and 1 mg l.1 significantly decreased the percentage germination of B. volubilis and E. autumnalis respectively. Cadmium and Hg at 2 mg l.1 showed a negative effect on the root growth of B. volubilis. Concentrations of 0.5 mg l.1 of all heavy metals tested significantly decreased shoot length of M. plumbea. The effect of Cd on biological activity (anti-inflammatory, antibacterial and antifungal) of medicinal plants with previously confirmed activity was evaluated. When supplied with Cd at 2 mg l-1, Eucomis humilis bulbous extracts showed lower anti-inflammatory activity than the control for both COX-1 and COX-2 activity. Eucomis autumnalis bulbous extracts had greater COX-1 activity compared to the control. However, Cd suppressed the activity of COX-2. Compared with non-Cd-treated Merwilla plumbea plants (control), those supplied with Cd at 10 mg l-1 showed increased antibacterial activity against Bacillus subtilis, Klebsiella pneumoniae and Staphylococcus aureus. However, no change in activity against Escherichia coli was observed. Cadmium accumulation in the bulbs had no effect on antifungal activity of Tulbaghia violacea. Thus, optimized agricultural practices are essential for quality control of cultivated medicinal plants. The studies presented in this thesis collectively answer several questions related to heavy metal involvement in South African medicinal plants. The findings substantiate the need to regulate and monitor the South African medicinal plant trade against heavy metal contamination which will in turn provide a product of safety and quality to the consumer.Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
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"Identification, purification and biological studies of the lead compound from Chinese herbs for the reactivation of fetal hemoglobin expression." 2003. http://library.cuhk.edu.hk/record=b6073529.
Full textAbstract:
Xing Hongtao."February 2003."
Thesis (Ph.D.)--Chinese University of Hong Kong, 2003.
Includes bibliographical references (p. 149-176).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Mode of access: World Wide Web.
Abstracts in English and Chinese.
50
"Immunomodulatory effects and toxicity of mimosa pudica, the sensitive plant." Chinese University of Hong Kong, 1993. http://library.cuhk.edu.hk/record=b5887741.
Full textAbstract:
by Cheng Yuk Kwan, Anna.Thesis (M.Phil.)--Chinese University of Hong Kong, 1993.
Includes bibliographical references (leaves 104-112).
Acknowledgements
Table of Contents --- p.i
Abbreviations --- p.iv
Abstract --- p.vi
List of figures --- p.ix
List of tables --- p.xi
Chapter Chapter One: --- Introduction
Chapter 1.1 --- Objective and scope of the project --- p.1
Chapter 1.2 --- Literature review of Mimosa pudica
Chapter 1.2.1 --- Morphology of Mimosa pudica --- p.3
Chapter 1.2.2 --- Chemistry of Mimosa pudica --- p.5
Chapter 1.2.3 --- Uses in traditional medicine --- p.5
Chapter 1.2.4 --- Clinical and pharmacological studies of Mimosa pudica --- p.6
Chapter 1.2.5 --- Toxicology of Mimosa pudica --- p.8
Chapter 1.2.6 --- Characteristics and toxicology of mimosine --- p.9
Chapter 1.3 --- Immunomodulation
Chapter 1.3.1 --- Overview of the immune system --- p.11
Chapter 1.3.2 --- Strategies on the study of immunomodulation of Mimosa pudica --- p.13
Chapter 1.4 --- Toxicology
Chapter 1.4.1 --- Principles of the toxicological assays
Chapter 1.4.1.1 --- LD50 --- p.17
Chapter 1.4.1.2 --- Enzyme assays --- p.18
Chapter 1.4.1.3 --- Subacute toxicity test --- p.24
Chapter 1.4.1.4 --- Reproductive toxicity test --- p.25
Chapter Chapter Two: --- Materials and methods
Chapter 2.1 --- Materials
Chapter 2.1.1 --- Mimosa pudica --- p.27
Chapter 2.1.2 --- Animals --- p.27
Chapter 2.1.3 --- Chemicals --- p.28
Chapter 2.2 --- Methods
Chapter 2.2.1 --- Extraction of Mimosa pudica --- p.32
Chapter 2.2.2 --- Assays for the immunomodulatory effects of Mimosa pudica
Chapter 2.2.2.1 --- Cell preparation
Chapter a) --- Splenocytes --- p.35
Chapter b) --- Thymocytes --- p.35
Chapter c) --- Macrophages --- p.36
Chapter 2.2.2.2 --- Splenocyte proliferation --- p.37
Chapter 2.2.2.3 --- Thymocyte proliferation --- p.38
Chapter 2.2.2.4 --- Phagocytic activity of macrophages --- p.39
Chapter 2.2.2.5 --- Release of IL-1 by macrophages --- p.40
Chapter 2.2.2.6 --- Plaque forming cells --- p.41
Chapter 2.2.2.7 --- Restoration on splenocyte blastogenesis of old mice --- p.42
Chapter 2.2.3 --- Assays for the toxicity of Mimosa pudica
Chapter 2.2.3.1 --- LD50 --- p.43
Chapter 2.2.3.2 --- Enzyme assays --- p.43
Chapter 2.2.3.3 --- Subacute toxicity --- p.43
Chapter 2.2.3.4 --- Reproductive toxicity --- p.44
Chapter 2.2.4 --- Statistical analysis --- p.44
Chapter Chapter Three: --- Results
Chapter 3.1 --- Immunomodulatory effects of Mimosa pudica
Chapter 3.1.1 --- In vitro study on the lymphocyte proliferation
Chapter 3.1.1.1 --- Splenocyte proliferation --- p.45
Chapter 3.1.1.2 --- Thymocyte proliferation --- p.50
Chapter 3.1.2 --- In vivo study on the lymphocyte proliferation --- p.53
Chapter 3.1.3 --- Phagocytic activity of macrophages --- p.58
Chapter 3.1.4 --- Release of IL-1 by macrophages --- p.64
Chapter 3.1.5 --- Plaque forming cells --- p.67
Chapter 3.1.6 --- Restoration on splenocyte blastogenesis of old mice --- p.69
Chapter 3.2 --- Toxicity of Mimosa pudica
Chapter 3.2.1 --- LD50 --- p.72
Chapter 3.2.2 --- Enzyme assays --- p.75
Chapter 3.2.3 --- Subacute toxicity --- p.80
Chapter 3.2.4 --- Reproductive toxicity --- p.85
Chapter Chapter Four: --- General discussion on the immunomodulatory effects and toxicity of Mimosa pudica
Chapter 4.1 --- Immunomodulatory effects of Mimosa pudica --- p.88
Chapter 4.2 --- Toxicity of Mimosa pudica --- p.95
Chapter Chapter Five: --- Concluding remarks --- p.99
References --- p.104
Appendix --- p.113