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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.
61

Analise de extratos de plantas medicinais pelo metodo de ativacao com neutrons

VAZ, SANDRA M. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:38:56Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:47Z (GMT). No. of bitstreams: 1 02753.pdf: 2050243 bytes, checksum: bad09f6ca0af45251626c9a6196f689f (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
62

Analise de extratos de plantas medicinais pelo metodo de ativacao com neutrons

VAZ, SANDRA M. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:38:56Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:47Z (GMT). No. of bitstreams: 1 02753.pdf: 2050243 bytes, checksum: bad09f6ca0af45251626c9a6196f689f (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
63

Penetration evaluation and PLGA nanoparticle development of curcumin for topical delivery to treat psoriasis

Sun, Lin January 2017 (has links)
University of Macau / Institute of Chinese Medical Sciences
64

廣藥和南藥的來源、分佈與應用歷史考

朱家駿, 01 January 2010 (has links)
No description available.
65

The effect of in vitro digestion on selected biological activities of Hypoxis sobolifera corms

Van Rooyen, Anzel January 2013 (has links)
In South Africa part of the cultural and religious beliefs of the African people is the use of traditional remedies to treat diseases. These remedies are obtained from medicinal plants (Steenkamp, 2003). One of the most frequently traded plants in the Eastern Cape is Hypoxis, commonly known as Afrika patat, or African potato. South African traditional healers instruct patients to brew the fresh Hypoxis corm as a tea and then ingest it (Steenkamp, 2006a). This prompted an investigation into the digestive stability of a traditionally prepared Hypoxis extract. The H. sobolifera extracts were digested using a simulated gastric/small intestinal digestion and their biological activity determined. The hot water H. sobolifera extract before digestion only showed cytotoxic activity against cancer cell lines at very high concentrations which are not likely to be achieved under normal ingestion circumstances. In Chang liver cells on the other hand, chronic exposure to the hot water H. sobolifera extract increased glucose uptake in amounts similar to that of metformin. On the negative side, the glucose utilization stimulation was lost due to the simulated digestion process. The significant inhibition of AGEs by hot water H. sobolifera extract (IC50 of 6.3 Ig/ml) is a very encouraging result as treatment in the management of diabetes. This activity was only slightly reduced by the in vitro digestion process. Also observed was enzyme inhibition activity by traditionally prepared H. sobolifera, with ∝-amylase being inhibited (IC50 of approximately 250 Ig/ml) and therefore preventing or limiting starch breakdown. From the DPPH results it was clear that H. sobolifera, even when digested, is a potent anti-oxidant (IC50 of 134.4 Ig/ml when undigested compared to 162.9 when digested with β-glucosidase added to stomach digestive step). HPLC and TLC experiments revealed that rooperol which has previously been thought to be the compound responsible for the anti-oxidant activity in Hypoxis extracts, was absent from the traditional extract of H. sobolifera and therefore cannot be the sole compound exhibiting anti-oxidant activity; other compounds such as phenolics may be contributing. The phenolic and flavonoid content results revealed very highconcentrations of these compounds in the traditionally prepared H. sobolifera extract. These compounds may therefore play major roles in all of the biological activities observed from treatment with Hypoxis spp. The ROS results yielded interesting and promising results. Using standard or traditionally prepared H. sobolifera extracts, activation of differentiated U937 cells with PMA was greatly enhanced by cotreatment with the extracts, while extracts on their own did not cause significant activation. Future studies should investigate this property of the extracts as a promising immune boosterThe HPLC results showed that hypoxoside was undetectable in the hot water traditional extract and the TLC anti-oxidant experiment proved that rooperol is not present in the hot water traditional extract after treatment with β-glucosidase. This indicates that neither one of the Hypoxis compounds previously believed to be responsible for the biological activities observed are present in the extract when prepared the traditional way. Therefore, the biological activities observed in this study can be attributed to other phytochemical compounds.
66

The effects of a Kenyan antidiabetic plant on insulin homeostasis

Suleiman, Khairunisa Yahya January 2009 (has links)
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.
67

Use of ethnoveterinary medicinal plants in cattle by Setswana-speaking people in the Madikwe area of the North West Province

Van der Merwe, Deon 13 September 2010 (has links)
The role of plants in the treatment of disease and enhancement of production in animals in South African rural communities is poorly documented. Rapid Rural Appraisal (RRA) methods were employed to describe the use of ethnoveterinary medicinal plants in cattle by Setswana-speaking people in the Madikwe area of the North West Province of South Africa. Information was gathered from key spokespersons through individual interviews, group interviews, guided field walks and observations. Ethnoveterinary uses in cattle of 46 plant species representing 24 families were recorded. Plants were used in 84 % of the total number of ethnoveterinary remedies. These plants were used alone (64 %) or in mixtures (36 %) for 43 indications. The most important indications for the use of ethnoveterinary remedies were retained placenta, diarrhoea, gallsickness, fractures, eye inflammation, general ailments, fertility enhancement, general gastrointestinal problems, heartwater, internal parasites, coughing, redwater and the reduction of tick burdens. Plant materials were prepared in various ways including, infusion (36 %), decoction (33 %), infusion or decoction (13 %), ground fresh material (6 %), sap expressed from fresh material (3 %), charred (2 %) and dried (1 %). Unprocessed, fresh material was used in 6 % of remedies. The most common dosage form was a liquid for oral dosing (83 %). Other dosage forms included, drops, licks, ointments, lotions and powders. Liquid remedies for oral dosing were administered using a bottle. The study indicated that Setswana-speaking people in the North West Province have a rich heritage of ethnoveterinary knowledge, which includes all aspects of ethnoveterinary medicinal plant use. The impact of ethnoveterinary medicinal plant use on medicinal plant population densities was also assessed through a comparison of the medicinal plant densities inside and outside the Madikwe Game Reserve. Belt transects were used in a stratified trial design to record plant densities. No statistically significant differences in medicinal plant densities that could be attributed to medicinal plant use, were found. / Dissertation (MSc)--University of Pretoria, 2000. / Paraclinical Sciences / Unrestricted
68

Evaluation of six plant species used traditionally in the treatment and control of diabetes mellitus

Boaduo, Nana Kwaku Kyei 22 December 2010 (has links)
Diabetes mellitus is becoming an increasing concern all over the world. Many people especially in poor communities have been using medicinal plants to treat diabetes and its complications. Much work has been done to find scientific evidence to support the use of medicinal plants in many cases with good evidence to support the traditional use. There has been an increase in research on the use of botanicals for either the treatment and/or management of diabetes in many parts of the world. To start this study an informal survey on plant species used to treat diabetes was carried out with local inhabitants and herbal traders in the Newcastle region (KwaZulu Natal). The plant species were chosen based on their wide use by traditional healers and local inhabitants. The efficacy of the selected plant (Senna alexandrina, Cymbopogon citrates, Cucurbita pepo, Nuxia floribunda, Hypoxis hemerocallidea and Cinnamomum cassia) used to treat diabetes mellitus by traditional healers in KwaZulu Natal province of South Africa was evaluated under controlled laboratory conditions. With the exception of Senna alexandrina and Nuxia floribunda, there has been some independent evidence of the efficacy of these plant species In this study three relevant in vitro and semi in-vivo assays were selected to test the efficacy of different extracts on alpha amylase (carbohydrate digestive enzyme) activity, alpha glucosidase (glucose absorption) activity and islets of Langerhans insulin secretory activity. Hexane, ethyl acetate, acetone and methanol extracts were examined and screened for their phytochemical properties and activity in the selected assays Alpha amylase inhibitory assay Not all extracts of the plant species had α-amylase enzyme inhibitory activity. The acetone extracts of C. pepo and H. hemerocallidea had enzyme inhibition less than that of acarbose positive control (EC50 = 1.82, 0.92 and 0.56 mg/ml respectively). The other plant species that had substantial α-amylase inhibitory activity was the methanol extracts of C. citratus and C. cassia (EC50 = 0.313 and 0.12 mg/ml respectively), ethyl acetate extracts of C. citratus and N. floribunda (EC50 = 1.20 and 1.60 mg/ml respectively). The hexane extracts of C. cassia (0.72 mg/ml), N. floribunda (0.88 mg/ml), C. pepo (0.70 mg/ml) and S. alexandrina (0.083 mg/ml) all had α-amylase inhibitory activity.The best activity was present in the intermediate polarity extracts. If these more apolar plant extracts are not toxic or do not have negative side effects they may be much more efficient than acarbose in managing α-amylase activity. Alpha glucosidase inhibitory assay In contrast to the alpha amylase activity, the inhibitory activity of the non-polar (hexane and ethyl acetate) plant extracts was in general higher than that of polar extracts. With the methanol and acetone extracts the inhibitory activity varied from no activity in the methanol extract of C. cassia to highly active methanol extract of C. pepo (70.3%) and acetone extract of H. hemerocallidea (84.35%). Among the plants studied C. cassia and N. floribunda (bark) had the highest inhibitory activity in the hexane and ethyl acetate extracts, the acetone extract of H. hemerocallidea had the highest inhibitory activity. The hexane crude extracts ofN. floribunda and C. citratus had very high inhibitory activity at the highest concentration tested (1 mg/ml). The ethyl acetate crude extracts of all the plant species used in this study had an inhibitory activity above 90% against α-glucosidase at 1 mg/ml. When compared to acarbose all the plant species used in this screening study had good activity against the α-glucosidase enzyme with the exception of the methanol extract of C. cassia. The inhibitory activity of hexane and ethyl acetate extracts was close to that of the positive control. If the more non-polar plant extracts are not toxic or do not have negative side effects (not tested) it appears that they may be more or less efficient than acarbose in managing α-glucosidase activity. Islets of Langerhans as a target site Only with the H. hemerocallidea acetone extract was there an increase in insulin secretion of 2.5 mIU/L (Table 8) at 8 ug/ml. With all the other extracts the insulin levels were less than 0.2 mIU/L. The positive controls of acarbose and glibenclamide at a concentration of 1 mg/ml stimulated insulin secretion to 11.5 and 19.8 mIU/L respectively. In comparison, the positive controls acarbose and glibenclamide control produce a 5-8 fold greater increase in insulin secretion although the exposure was at a 100-fold higher concentration. This would indicate that the H. hemerocallidea acetone crude extract contains a very potent secretogogue compound. It is possible that higher concentrations of the other plant extracts may also have led to stimulation of insulin production. If the more non-polar plant extracts are not toxic or do not have negative side effects and are biologically available, it appears that they may be much more efficient than acarbose and glibenclamide in managing insulin secretion. Conclusion The best overall activity was observed in the non-polar and intermediate solvents (hexane and ethyl acetate). Although the organic extracts had good activity, it does not explain the use of aqueous extracts by traditional healers because water extracts were not active in the assays. The activity of the C. pepo acetone leaf extract and N. floribunda ethyl acetate bark extract is the first reported evidence of activity with regard to diabetes mellitus. From the in vitro results, it can be concluded some extracts of all the traditionally used species have some merit in the management of diabetes mellitus type II, as suggested by the ethnomedicinal leads. In may be worthwhile following up on this work by isolating the compounds responsible for the biological activities. / Dissertation (MSc)--University of Pretoria, 2010. / Paraclinical Sciences / unrestricted
69

The traditional use of medicinal plants to treat erectile dysfunction and the isolation of their bioactive compounds

Rakuambo, N.C. (Ntungufhadzeni Christopher) 12 March 2012 (has links)
Please read the abstract in the dissertation Copyright 2002, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Rakuambo, NC 2002, The traditional use of medicinal plants to treat erectile dysfunction and the isolation of their bioactive compounds, MSc dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-03122012-172112 / > E12/4/140/gm / Dissertation (MSc)--University of Pretoria, 2002. / Plant Science / unrestricted
70

An evaluation of plants used in eastern Nigeria in the treatment of epilepsy and convulsion.

Ogbonnia, Steve Okwudili. 12 December 2013 (has links)
Schumanniophyton magnificum and Glypheae brevis are important medicinal plants growing wild in the West African rain forest. They are used in folkloric medicine in the treatment of epilepsy and convulsion as well as for some other diseases. The purpose of this work was to investigate the aspect of folkloric use in order to support folkloric claims and document the findings. The extracts were prepared from ground plant material by a continuous extraction method. Five hundred grams of ground plant material were continuously de-fatted with 2 L petroleum ether (60°- 80°) in a Soxhlet apparatus for about 5 h. The resulting marc was dried and the chemical constituents extracted hot in a Soxhlet apparatus for about 8 to 10 h with 2 L aqueous ethanol (70%). The efficacy of the extraction method was confirmed using standard bioassays and phytochemical analyses. The anti-convulsant activity of the crude extracts was evaluated in vivo against chemically induced convulsions using three different animal models, namely the strychnine, the picrotoxin and the pentylenetetrazole tests. The acute and delayed toxicity test results showed that in all the animal models investigated very high doses, about four times higher than the protective doses of the extracts, were required to kill 50% of the population of animal used. Phytochemical assays of the extracts indicated the presence of alkaloids only in S. magnificum root extract and glycosides in extracts from both species. The glycosides were positive to Baljet, Xanthydrol and Keller-Kiliani tests for cardiac glycosides. S. magnificum and G. brevis chemical constituents were initially isolated with a sequential fractionation method starting with a highly non-polar solvent and gradually increasing to a more polar solvent. The fractions were pooled on the basis of TLC similarity profiles when viewed under the UV light at 254 and 366 nm and were found to have two and four major UV absorbing fractions for S. magnificum and G. brevis respectively. Radio-receptor binding tests were used to assess the anti-convulsant activities of the hydro-alcoholic crude extracts, the organic and aqueous fractions of the crude extracts, partially purified components and pure components in in vitro tests against some standard GABA[A] receptor antagonists, muscimol and isoguvacine respectively. The anti-convulsant activities resided in the aqueous fractions of the hydro-alcoholic crude extracts of both plants. The purely organic fractions of G. brevis demonstrated no activity while all the fractions of the aqueous component demonstrated some degree of activity. The anti-convulsant activity of S. magnificum was found only in one fraction-Fraction 1. This Fraction was further investigated and one of the components appear to be responsible for the activity. The structure of the active constituent was 5,7dihdroxy-2 methylbenzopyran-4-one, a noreugenin. A second bioactive compound, schumanniofoside, was identified from Fraction M[5.2] from S. magnificum. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 2002.

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