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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Antimicrobial efficacy and toxicity profiles of conventional antimicrobial agents in combination with commercially relevant southern African medicinal plants

Hubsch, Zelna 27 August 2014 (has links)
Thesis (M.Pharm.)--University of the Witwatersrand, Faculty of Health Sciences, 2014. / Traditional medicine plays a vital role in the cultural heritage of many South Africans, with at least 80% of the population relying on medicinal plants for their primary source of healthcare. It has been acknowledged that even in some of the finest hospitals in South Africa, people are often found to be using traditional medicine in combination with conventional treatment regimens. Despite the substantial use of medicinal plants in South Africa, limited information is available on the interactive properties between commercially relevant, southern African medicinal plants and conventional drugs. Furthermore, the potential for toxicity of these combinations has been sorely neglected. In orthodox medicine, antimicrobials such as antibiotics and antifungals are amongst the most commonly prescribed group of drugs. Therefore, there is a high probability for the concurrent use of these two forms of healthcare. The aim of this study was to evaluate the interactive antimicrobial and toxicity profiles, when seven conventional antimicrobial agents (amphotericin B, ciprofloxacin, erythromycin, gentamicin, nystatin, penicillin G and tetracycline) were combined with the essential oils, aqueous and organic extracts of seven medicinal plants (Agathosma betulina, Aloe ferox, Artemisia afra, Aspalathus linearis, Lippia javanica, Pelargonium sidoides and Sutherlandia frutescens). The antimicrobial activity of the plant samples and conventional antimicrobials were evaluated, alone and in combination, using the minimum inhibitory concentration (MIC) assay against two yeasts, three Gram-positive and three Gram-negative bacteria. The combinations were further evaluated using the fractional inhibitory concentration (ΣFIC) assessment. Combinations demonstrating notable synergistic or antagonistic interactions were studied in various ratios (isobolograms). Toxicity of the antimicrobials and plant samples were assessed, individually and in combination, using the brine-shrimp lethality assay (BSLA) and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell proliferation assay on human kidney epithelial cells (Graham or HEK-293 cell line). A total of 476 combinations were assessed for interactive antimicrobial potential. Of these combinations, 14.29% were synergistic, 7.56% antagonistic, 35.71% additive and 42.44% indifferent in nature. Some notable interactions were identified, such as the combination of A. linearis (aqueous and organic extract) with penicillin G, where a synergistic profile was most often seen against the three tested Gram-positive micro-organisms (Staphylococcus aureus, Bacillus cereus and Enterococcus faecalis), with ΣFIC values ranging from 0.01 (synergistic) to 0.94 (additive). Further notable interactions included A. betulina and S. frutescens, when combined with ciprofloxacin and tested against E. coli, which demonstrated a favourable synergistic profile, and could be of importance in the treatment of urinary tract infections. In the BSLA, the notable interactions that were tested demonstrated no toxic effect. In the MTT cellular viability assay, the only combination demonstrating possible toxicity was that of A. linearis (aqueous and organic extract) in combination with nystatin (inhibitory effects of 73.76 ± 3.36% and 56.88 ± 6.61%, respectively). Therefore, concurrent use should be cautioned and further in vivo studies warranted. In conclusion, most combinations were found to be non-interactive, alleviating some of the concern related to the concurrent use of the two forms of healthcare. However, some notable combinations were identified, which could possibly have an impact on conventional treatment regimens. Therefore, further in vivo testing is warranted to support the in vitro findings.
2

Effects of a crude Aloe vera leaf extract on diet-induced metabolic dysfunction in growing rats

Gasa, Zinhle Pearl 05 April 2013 (has links)
The high prevalence of metabolic syndrome in children is mainly due to the adoption of an unhealthy diet and a sedentary lifestyle. The disorder is also associated with obesity, insulin resistance, hypertension and increased blood levels of triglycerides, free fatty acids and glucose. Although metabolic syndrome and its metabolic complications can be managed by the use of conventional medicines such as fenofibrate and metformin, there is a growing use of plants with medicinal properties. Aloe vera has been used for several medicinal purposes such as wound and burn healing, treatment of diabetes and treatment of cancer. Aloe vera also has biological activities that include anti-inflammatory, anti-microbial and laxative effects. Previous studies exploring the metabolic effects of Aloe vera have been in adult animals where metabolic syndrome was induced by the use of pharmacological agents. However, its beneficial effects in growing children who are at risk of developing metabolic syndrome have not been fully explored. The objectives of this study were to evaluate the effects of a crude Aloe vera leaf extract on circulating metabolic substrates, the morphometry and morphology of the gastrointestinal tract and the liver function of growing rats. Fifty-nine male Sprague-Dawley rats of 21 days old were randomly divided into one of six treatment groups. Group I (control) was fed normal rat chow (NRC) with plain gelatine cubes (vehicle). Group II received a high carbohydrate diet (HCD) with plain gelatine cubes; Group III received normal rat chow and fenofibrate at 100mg.kg-1; Group IV received a HCD and fenofibrate at 100mg.kg-1; Group V received a normal rat chow and Aloe vera at 300mg.kg-1; Group VI received a HCD and Aloe vera at 300mg.kg-1. The Aloe vera and fenofibrate were suspended in gelatine cubes and administered daily. After 20 weeks of feeding, the rats were fasted over night and an oral glucose tolerance test (OGTT) was performed. The rats were then euthanazed after 48 hours of re-feeding and tissues were collectedfor further analysis. The data was expressed as mean ± SEM and analyzed by a one-way ANOVA. A repeated measures ANOVA was used for statistical analysis of the data from the oral glucose tolerance test. The values were considered statistically significant when p < 0.05 followed by a Bonferroni Post hoc test. After 20 weeks, the growing rats fed a high carbohydrate diet had a significantly higher body mass than the other groups (p < 0.05, ANOVA), however the administration of fenofibrate prevented the high carbohydrate-induced increase in body mass whilst Aloe vera was not effective. Linear growth as measured by the tibial length was not significantly different between the groups (p >0.05, ANOVA). There was no significant difference in the mass and relative density of the tibia bones of the rats between the groups. Feeding rats a HCD resulted in a higher (p< 0.05, ANOVA) visceral fat mass in the rats. Fenofibrate administration prevented the HCD-induced visceral fat mass gain whilst Aloe vera administration had no effect. Whilst the treatments did not result in any significant differences in the lengths and mass of the small intestine, the mass of the large intestine was significantly lower in the rats that received the HCD alone (p < 0.05, ANOVA). Fenofibrate administration resulted in a significantly increased liver mass compared to the other groups (p < 0.05, ANOVA). However there was no significant difference in the lipid and glycogen content in the liver. Fasting concentrations of metabolic substrates (glucose, triglycerides and free fatty acids) were not significantly different between the groups and no significant differences were observed in the circulating concentrations of insulin and the homeostasis model assessment of insulin resistance (HOMA-IR) (ANOVA; p>0.05). The OGTT did not show any abnormalities in the ability of the rats to handle a glucose load between the groups. An indirect assessment of liver function was performed by measurements of the blood concentrations of alkaline phosphatase (ALP), total bilirubin (TBIL), alkaline transaminase (ALT) and gamma-glutamyl transferase (GGT). There were significantly increased (p<0.05) ALP levels in rats fed NRC + FENO compared to the others. TBIL levels were significantly lower in rats fed a NRC + Av (p< 0.05, ANOVA) however the TBIL levels were within the normal range. The alkaline transaminase (ALT) levels were not significantly different between the groups (p < 0.05, ANOVA) and GGT was not detectable in any of the groups. Weaning rats onto a high carbohydrate diet and feeding them the diet for 20 weeks resulted in the development of visceral obesity without altering the glucose tolerance and metabolic substrates. The treatment with fenofibrate prevented the high carbohydrate diet-induced visceral adiposity however compared to fenofibrate, treatment with the Aloe vera leaf preparation was not significantly effective.
3

Synergistic interactions of lavender essential oil

De Rapper, Stephanie 19 February 2014 (has links)
Thesis (M.Pharm.)--University of the Witwatersrand, Faculty of Health Sciences, 2013. / Essential oils are not only used singularly but have been used in combination for many years. There is, however, very little scientific evidence to support the claims made for combined antimicrobial efficacy. With this in mind, a study was designed to investigate the antimicrobial activity of Lavender (Lavandula angustifolia) essential oil, in combination with other essential oils with antimicrobial relevance. The micro-dilution minimum inhibitory concentration (MIC) assay was undertaken, whereby the fractional inhibitory concentration (ƩFIC) was calculated for 54 oil combinations. When lavender oil was assayed in 1:1 ratios with other oils, synergistic (23.5%), additive (52.5%), non-interactive (23.5%) and antagonistic (0.5%) interactions were observed. Four 1:1 combinations were synergistic against Candida albicans and Staphylococcus aureus (Lavandula angustifolia in combination with Daucus carota (ΣFIC 0.50 and 0.50); Juniperus virginiana (ΣFIC 0.50 and 0.50); Cinnamomum zeylanicum (ΣFIC 0.40 and 0.50) and Citrus sinensis (ΣFIC 0.42 and 0.38)). In order to understand the antimicrobial potential of these synergistic essential oil combinations, further antimicrobial analysis was undertaken whereby the oils were placed in varying ratios. Two of the four combinations (Lavandula angustifolia in combination with either Cinnamomum zeylanicum or Citrus sinensis), were identified as the most promising, demonstrating synergy at varying ratios, and thus the major chemical constituents of the essential oils were investigated further. The major chemical constituents identified in Lavandula angustifolia (GC-MS) were linalyl acetate (36.7%), linalool (31.4%) and terpinen-4-ol (14.9%). The GC-MS profiles for all other oils in the study were also confirmed. The major chemical constituents of the most promising essential oil combinations were investigated in equal and varying ratios to determine the effect of chemistry on antimicrobial outcome. When one of the major essential oil constituents (linalyl acetate) of Lavandula angustifolia was combined with limonene found in Citrus sinensis, synergistic interactions were noted for all nine combinations against C. albicans; including the ratio at which the two major constituents would be mixed should the two oils be combined. Lavandula angustifolia essential oil was placed in combination with four conventional antimicrobial agents (ciprofloxacin, chloramphenicol, fusidic acid and nystatin) to determine which of these agents in combination with Lavandula angustifolia would demonstrate the best antimicrobial effect. Synergy was determined for Lavandula angustifolia in combination with ciprofloxacin against S. aureus (ΣFIC of 0.49) and Lavandula angustifolia in combination with chloramphenicol against P. aeruginosa (ΣFIC of 0.29). No antagonism was noted for the combinations investigated. When placed in variable ratios it was identified that Lavandula angustifolia provided the pivotal role in the synergistic interactions observed against C. albicans and S. aureus, with ratios higher in Lavandula angustifolia essential oil concentration showing considerably better antimicrobial effects. In order to determine the antimicrobial effects of Lavandula angustifolia in triple essential oil combinations, the method of MODDE® Design of Experiments was employed. The Design of Experiments (MODDE 9.1®) software identified that Lavandula angustifolia (from the combination of Lavandula angustifolia: Citrus sinensis: Cedrus atlantica) and Thymus vulgaris (from the combination of Lavandula angustifolia: Daucus carota: Thymus vulgaris) were the essential oils with the greater antimicrobial effect in the combinations analysed. Lavender remains one of the most sought after essential oils. This comprehensive study on the antimicrobial effects of Lavender (Lavandula angustifolia) combinations demonstrates promising in vitro effects and lends some credibility for combined use in aromatherapy for the treatment of infections
4

The effect of Dodonaea viscosa var. Angustifolia (L.F.) on the ultrastructure of Candida albicans cell wall and biofilm formation

Naicker, Serisha Devi January 2012 (has links)
Dissertation submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Master of Science in Medicine. Johannesburg, 2012 / Oral candidiasis is an infection prevalent in immunocompromised individuals. The main causative agent is Candida albicans. Many antifungal agents are available and are effectively used. However, due to the development of drug resistance, toxicity and poor solubility resulting in poor absorption; medicinal plants have been investigated. Dodonaea viscosa var. angustifolia, an indigenous South African plant has shown to have an antifungal effect including inhibition of adherence of C. albicans to oral epithelial cells; which is the crucial first step of infection. This study investigated the effect of the crude extract on the ultrastructure of C. albicans cell wall, which might be responsible for the reduced adherence to oral epithelial cells. The effect of the plant extract on C. albicans germ tube and biofilm formation was also studied since biofilm structure allows for high resistance to antifungal agents and host defense mechanisms. Crude plant extracts were prepared using dried leaves and acetone. Three C. albicans strains were used throughout the study. Minimal fungicidal concentrations of plant extract were determined using a microdilution technique. Three subinhibitory concentrations 3.125, 1.562 and 0.781 mg/ml were selected for further studies. The effect of these subinhibitory concentrations of plant extract on the C. albicans cell wall structure, cell membrane, germ tube formation, biofilm formation and cell wall proteins were studied using transmission electron microscopy, light microscopy, scanning electron microscopy and SDS-PAGE respectively. v The subinhibitory concentrations of crude plant extract rendered C. albicans cell wall thinner and at some places caused cell wall breakage and disruption. This effect increased with a decrease in plant extract concentration. The cell membrane was also damaged by the plant extract showing increased undulation. This effect was not concentration dependent. The subinhibitory concentrations decreased C. albicans germ tube formation and the effect increased with an increase in concentration. Biofilm formation was reduced by the plant extract and in addition, hyphal formation by cells within the biofilm was also reduced. However, SDS-PAGE showed that on a molecular level, the plant extract did not remove any specific adhesin proteins from the cell wall. The crude plant extract of D. viscosa var. angustifolia at high concentrations, kills C. albicans and at low concentrations, renders the surviving cells avirulent. Therefore it has the potential to be developed into an effective therapeutic agent to treat and prevent oral candidiasis. However, further research is required to identify the mode of action of the extract, the specific chemicals responsible for the effect, and the cytotoxicity.
5

Antimicrobial interactions of Artemisia afra used in African traditional medicine

Suliman, Sajida 17 January 2012 (has links)
Many therapies prescribed by traditional healers in Southern Africa include plant combinations to treat infectious diseases. Artemisia afra is one of the most commonly used traditional medicines in African traditional medicine and most often given in combination with other plants. This plant‟s popularity coupled with its wide range of uses in combination serves as the rationale for the bases of this study. In this study, combinations of A. afra (essential oils and plant extracts), which are commonly used for the treatment of respiratory diseases were studied from an antimicrobial perspective in order to determine if a scientific basis exists for their combined use. The plants used often in double or triple combination with A. afra in the treatment of respiratory tract infections are Lippia javanica, Osmitopsis asteriscoides, Agathosma betulina, Eucalyptus globulus, Allium sativum, Leonotis randii, Tetradenia riparia and Zanthoxylum capense. Essential oils from plant samples were analysed using gas chromatography coupled to mass spectroscopy (GC-MS). Compounds found in highest concentrations were camphor (41.0%) in A. afra, linalool (70.7%) in L. javanica, 1,8-cineole (59.0%) in O. asteriscoides, isomenthone (31.4%) in A. betulina, 1,8-cineole (63.0%) in E. globulus and β-caryophyllene (32.4%) in T. riparia. Dichloromethane: methanol extracts and aqueous extracts were prepared for each plant using the dried ground plant material collected. The antimicrobial activities of each sample as well as each combination (including essential oils) were tested using the minimum inhibitory concentrations (MIC) assay against a panel of respiratory tract organisms. The highest sensitivities observed for the essential oils were that of E. globulus against Cryptococcus neoformans with a MIC value of 0.6 mg/ml. The dichloromethane: methanol extracts showed the most activity with E. globulus against Moraxella catarrhalis (MIC value of 0.01 mg/ml). The aqueous extracts showed the best activity with Z. capense against Streptococus agalactiae with a MIC value of 0.4 mg/ml. The 1:1 fractional inhibitory concentration (ΣFIC) values of the combinations of A. afra with L. javanica, A. afra with O. asteriscoides, A. afra with A. betulina, A. afra with E. globulus and A. afra with Z. capense were calculated from the MIC data. Synergy, additivity, indifference and antagonistic interactions within the combinations were then interpreted. The most significant interactions of the double combinations with synergistic ΣFIC values of 0.2 were the combination of the dichloromethane: methanol extracts of A. afra with O. asteriscoides against Streptococcus pyogenes and the combination of the aqueous extracts of A. afra with E. globulus against Streptococcus pneumoniae. Significant antagonism was noted with the combination of the dichloromethane: methanol extracts of A. afra with E. globulus against Enterococcus faecalis. The ΣFIC results of the combinations of A. afra with L. javanica, O. asteriscoides, A. betulina, E. globulus or with Z. capense were used to calculate ratios and plotted on to an isobologram. The isobolograms were interpreted with regard to any synergy, antagonism, or additive interactions present in the combination. Isobolograms revealed the most significant activity with the combination of the aqueous extracts of A. afra with E. globulus against C. neoformans with all the ratios tested being synergistic. The most prominent antagonism (five ratios) noted was in the combination (dichloromethane: methanol extracts) of A. afra with E. globulus against M. catarrhalis. The triple combinations analyzed for their antimicrobial activity were the combinations of A. afra with O. asteriscoides and E. globulus, A. afra with L. randii and E. globulus, A. afra with A. sativum and Z. capense and the combination of A. afra with T. riparia and salt. The most significant synergistic activity was noted for the combination of the essential oils A. afra with T. riparia and salt against Mycobacterium smegmatis with a ΣFIC value of 0.2. The combination of A. afra with O. asteriscoides and E. globulus of (dichloromethane: methanol extracts) displayed the most antagonistic activity against M. catarrhalis. When analysing the combinations that include A. afra, it was noted that adjuncts are an important combination ingredient in the traditional method of preparation. These were also tested for their activity. The combinations that include adjuncts i.e. honey, salt, vinegar, brandy and milk showed mainly indifferent interactions. This indifference noted supports the use of these adjuncts by traditional healers as it serves to verify that these adjuncts are at least not hindering the activity of the plant itself, which is a positive direction for future investigations. Traditional medicine, with regard to A. afra, as prescribed by traditional healers, has commonly employed the use of combinations of more than one plant to treat respiratory conditions. When the antimicrobial activities in combination were examined from a scientific viewpoint, there is evidence of some bases for their traditional use. The results obtained from the testing of the essential oils validate its traditional use as an inhalant. The dichloromethane: methanol extracts showed results varying from synergy to antagonism while the aqueous extracts showed good antimicrobial activity. It is recommended that future studies should be conducted into these interactions to determine the benefits of these combinations for possible use in the commercial and primary health-care sectors.
6

Studies on the antispasmodic principle of Euphorbia pilulifera

Hallett, Floyd Prentice, January 1951 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1951. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
7

Studies on the medicinal plants of Puerto Rico

Asenjo, Conrado F., January 1940 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1940. / Typescript. Includes abstract and vita. Includes bibliographical references (leaves 124-130).
8

Eficacia terapeutica da Casearia sylvestris sobre herpes labial e perspectica de uso em saude coletiva / Efficacy of Casearia sylvestris against simplex oral-infections perspectives in public oral health

Cury, Viviane Goreth Costa 28 October 2005 (has links)
Orientador: Francisco Carlos Groppo / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-11T17:14:09Z (GMT). No. of bitstreams: 1 Cury_VivianeGorethCosta_M.pdf: 1258018 bytes, checksum: c0cfbbb29e3fb226bc8962ba6d53ccb5 (MD5) Previous issue date: 2005 / Resumo: O herpes labial é uma das doenças virais humanas mais comuns e está fortemente associada ao ¿stress¿. Causada pelo vírus HSV, o herpes é uma patologia de grande relevância epidemiológica para os profissionais de saúde coletiva, pois é elevado o número de pacientes que procuram os serviços públicos de assistência. Na última década, novos paradigmas foram criados a respeito do conceito de saúde/doença e esta visão se caracteriza, principalmente, pela idéia de que a saúde não se limita à ausência de patologias, e sim à sensação de bem estar físico, emocional e social. Esta mudança tem favorecido o aparecimento e fortalecimento das chamadas correntes terapêuticas alternativas, tais como a medicina chinesa, a acupuntura, a fitoterapia, a homeopatia, dentre outras. O objetivo deste estudo foi avaliar a eficácia de cremes à base de tintura de Casearia sylvestris (Cs) a 10% (medicamento fitoterápico) e da Cs dinamizada em 3DH (medicamento homeopático) no tratamento de lesões herpéticas, comparando-os com creme de Penciclovir a 1% (Penvirlabia® - Sigma Lab.). Foi realizado um estudo duplo-cego, com amostra de 93 voluntários, de ambos os gêneros, com bom estado de saúde, com idade variando de 18 a 60 anos, residentes na região metropolitana de Belo Horizonte, que apresentavam lesão herpética labial. Foram formados aleatóriamente três grupos, sendo que cada um destes utilizou um dos medicamentos estudados. Os voluntários foram acompanhados até a cicatrização total da lesão. Os resultados demonstraram que os cremes de Casearia sylvestris induziram a uma cicatrização significativamente maior(Kruskal-Wallis,p<0.05) do que o creme de Penciclovir, pois foi menor a quantidade de dias, necessários para a cicatrização total das lesões. Foi possível considerar a utilização, dos medicamentos fitoterápico e homeopático, como uma alternativa ao tratamento convencional, tendo como principais vantagens a eficácia demonstrada e o baixo custo / Abstract: The labial herpes is a very common viral disease and it is strongly linked with stress. Caused by the HSV, herpes is a pathology of great importance to collective health professionals, because the number of patients who look for the public assistance service is high. In the last decade the society was created new patterns related to the concept of health/disease and this view is mainly because of the idea that it is not due to the absence of pathologies but also the physical/ emotional and social well being. These changes have been favoring the appearance and strengthening of the alternative therapies, such as chinese medicine, acupuncture, phytotherapy, homeopathy, and others. The objective of this study was to evaluate the efficiency of a salve based on Casearia Sylvestris (Cs) tincture to 10 % and from the dynamic 3dh in herpes treatement, comparing with the Penciclovir 1% salve (Penvirlabia ¿ Sigma lab ). A double -blind study was made with an assay of 93 volunteers, males and females, in good health conditions, with ages varying between 18 and 60,living in Belo Horizonte city, who demonstrated labial herpes sore. Three groups randomly were crated, each group used one of the studied medicines, and the volunteers were accompanied until the total sore healed. Results show that the Casearia Sylvestris salve caused one better and meaningful healing (KruskalWallis p<0,05), because the process happened in fewer days. It is possible to consider these medicines as one alternative rather than the conventional treatment, considering the low cost and high efficiency already demonstrated. / Mestrado / Saude Coletiva / Mestre em Odontologia
9

Ethnopharmacology and phytochemistry of some selected medicinal plants in KwaZulu Natal.

Ntuli, Siyabulela Sboniso Brightson Noel. January 2006 (has links)
In this ethnopharmacological study to isolate, purify, identify and test crude and isolated compounds from organic and aqueous extracts from stem and leaves of Protorhus longifolia and Sclerocarya birrea, stem bark of Hibiscus cannabinus and Heteropyxis natalensis, leaves of Acokanthera venenata, Carissa marcrocarpa and Syzygium cordatum, seeds of Chiononthus foveolatus and calyces of Hibiscus sabdariffa were tested against seven pathogenic microorganisms which included six bacterial species [Klebsiella pneumoniae (ATCC 12265), Bacillus cereus (ATCC 11778), Salmonella typhimurium (ATCC 13311), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 35219), Staphylococcus aureus (ATCC 29213)) and fungal yeast Candida albicans (ATCC 10231)]. Both organic and aqueous extracts from these medicinal plants exhibited antimicrobial properties against one or more mlcroorgamsms. The extracts of stem bark and leaves were tested for antimicrobial properties. Crude extracts that showed the highest activity were analysed through chromatographic and spectroscopic techniques to isolate, purify and characterise their active components. The highly active antimicrobial extracts were further tested for antimicrobial activity. Chromatographic (TLC and CC) spectroscopic (IR, 13C, 1HNMR) analyses of Syzygium cordatum leaf extract in ethyl acetate revealed the presence of C-30 triterpenes, ursolic (3B-hydroxyurs-12-en-28-oic acid) (UA) and oleanolic (3-hydroxylean-12-en-28-oic acid) (OA) acids; a mixture of methyl maslinate (2a, 3B-dihydroxyolean-12-en-28-oic acid methyl ester) (MM) and methyl corosolate (MC). Analyses of Protorhus longifolia leaf extract in hexane and ethylacetate revealed the presence of the alkaloid lupeol (lup-20(29)-en-3pB-ol), lupenone [lup - 20 (29) - en - 3 - one or lup - 20 ( 30 ) - en - 3 - one], lupinine (octahydro-2H-quinolizine-lmethanol), lupulon (3 ,5-dihydroxy-2,6,6-tris(3-methyl-2-butenyl)-4-(3-methy1-1-oxobutyl)-2,4-yclohexadien-1-one) or (3,5-dihdroxy-4-isovaleryl-2,6,6-tris(3-methyl-2-butenyl)-2, 4-cyclohexadien-1-one) and luteolin [(2-(3, 4-dihydroxyphenyl)-5, 7-dihydroxy-4H -1-benzopyran-4-one), 3',4', 5,7 -tetrahydroxyflavone or 5,7,3' 4' - tetrahydroxyflavone] and other compounds to be characterised in future studies. Sclerocarya birrea bark extract in methanol was found to contain mixtures of compounds that could not be separated due to solvent complications. Heteropyxis natalensis stem bark in ethyl acetate gave betunilic acid (3B-hydroxy-20(29)-lupaene- 28-oic acid) as a major compound. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2006.
10

Effects of crude leaf extracts of Ficus thonningii on growth, gastrointestinal morphometrry and clinical biochemistry of suckling Sprague Dawley rats

Dangarembizi, Rachael 17 February 2014 (has links)
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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