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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.
41

Diagnostic concepts and medicinal plant use of the Chatino (Oaxaca, Mexico) with a comparison of Chinese medicine /

Weiss, Janna, January 1998 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 378-392). Available also in a digital version from Dissertation Abstracts.
42

Bioactive sesquiterpenoids from dicoma anomala subsp. gerrardii

Van der Merwe, Marina Mikhailovna. January 2008 (has links)
Through South Africa’s first collaborative project between a large scientific organisation, the Council for Scientific and Indust rial Research (CSIR), and the Traditional Healer’s Committee, Dicoma anomala was identified as a plant containing potent anticancer and antimalarial compo unds. In the process of evaluation, extracted plant material with reported or anecdotal use for the treatment of respiratory problems was found to have significant anticancer activity in vitro in a 3-cell line preliminary screen . The extract was further shown to have potent anticancer activity against the 60-cell line panel at the National Cancer Institute (NCI) in the USA. Bioassay-guided fractio nation, initially utilising an in vitro anticancer assay, and structural elucidation resul ted in two potent compounds with sesquiterpenoid skeletons (C-15 and C-30). The crystal structure of the C-15 compound, not published previously, was obtained. B oth compounds were further screened in an antiplasmodial assay during the cour se of the National Drug Development Platform (RSA: CSIR, MRC and UCT) proje ct, and were found to have potent activity against Plasmodium falciparum (a malaria protozoon). Although the C-15 compound had a selectivity index (SI) of 10, suggesting that it was suitable for subsequent development, the dimer was highly toxic (SI index of 1), limiting opportunities for future development. A further study of the structure- activity relationship (SAR), which was initiated fo r the C-15 compound, showed that removal of each unsaturated structural compone nt decreased activity 10–fold in both bioassays. Additional investigations were c arried out into amino-acid Michael adducts with the exocyclic double bond of t he C-15 sesquiterpenoids, and the products were characterised by NMR spectroscopy and mass spectrometry. A similar investigation, involving the conjugate addi tion of simple amines, was undertaken in an attempt to enhance the bioavailabi lity of the parent sesquiterpenoid. Three diethylamine derivatives wer e prepared and characterised. A general 10-fold drop in the bioactivity of these “pro-drug” derivatives in both assays was observed. Finally, the C-15 compound was tested in vivo in the Plasmodium berghei murine malaria model and was found to have some eff ect on the survival rates of the laboratory animals when c ompared with the control. A possible mode of action is suggested based on the e xperimental and published bioactivity data. Further studies to improve the bi oactivity and alternative design of future in vivo studies are also proposed. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
43

Application of cucurbit[7]uril as an artificial receptor for seizure-inducing agents and anti-bacterial compounds

Kuok, Kit Ieng January 2018 (has links)
University of Macau / Institute of Chinese Medical Sciences
44

Isolation and structure elucidation of new compounds from Cornus Controversa and Delphinium Chrysotrichum

Unknown Date (has links)
The aim of this dissertation was to explore structurally unique secondary metabolites from herb medicinal plants Cornus controversa and Delphinium chrysotrichum. The introduction in the first chapter provides a detailed review about the research progress of chemical constitutents of the genus Cornus. In addition, its pharmacological activities were also summarized in this chapter to provide a framework for understanding the roles of medicinal herbs belong to genus Cornus as anti-diabetes therapeutics and to deliver useful information for further research. In chapter two, seven new compounds, including one iridoid glucoside, cornoside A (59), five iridoid aglycones, cornolactones A – E (60 – 64) and one indenone glucoside, cornoside B (65), together with 10 known compounds have been isolated from the leaves of Cornus controversa. The structures of these compounds were established by interpretation of spectroscopic data. Cornolactone A (61) is the first natural cis-fused tricyclic dilactone iridoid containing both a five- and six-membered lactone ring. Cornoside B (65) is the first alkaloid isolated from the genus Cornus bearing an indole-3-lactic acid-11--D-glucopyranoside skeleton. In chapter three, we described the structure elucidation of three new diterpenoid alkaloids delphatisine D (77), chrysotrichumines A (78) and B (79), as well as 11 known compounds from the whole plants of Delphinium chrysotrichum. Delphatisine D (77) is a rare atisine-type alkaloid from genus Delphinium and is the C-15 epimer of spiramine C which bears an internal carbinolamine ether linkage (NCOC) between C-7 and C-20. Chrysotrichumine A (78) is a rare natural C19-diterpenoid alkaloid possessing a nitrone group between C-17 and C-19. In addition, their cytotoxic activity against human breast cancer cell lines of MCF-7 and MDA-MB-231 were also reported. In chapter four, the detailed extraction and isolation procedures of the new compounds, cornosides A and B, cornolactones A – E, delphatisine D, chrysotrichumine A and B, as well as of all the known compounds were described. In addition, the experimental procedures for the determination of PPARγ and LXR agonistic activities and the MTT cytotoxicity assay were listed in this chapter. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
45

Phytochemical study of codonopsis tangshen: Tien Shui tangshen.

January 1980 (has links)
Wong Man-po. / Thesis (M. Phil.)--Chinese University of Hong Kong, 1980. / Bibliography: leaves 88-91.
46

Phytochemical studies on medicinal plants: alisma orientale and desmodium styracifolium. / CUHK electronic theses & dissertations collection

January 2005 (has links)
Forty-six constituents have been identified from an ethanol extract prepared from the aerial parts of Desmodium styracifolium, including seven triterpenes: lupeol (15), lupeone (16), olean-12-ene-3beta, 22beta-diol (sophoradiol) (19), olean-12-ene-3beta, 22beta, 24-triol (soyasapogenol B) (20), (23Z)-9, 19-cycloart-23-ene-3beta, 25-diol (21), (24R)-cycloart-25-ene-3beta, 24-diol (24a), and (24S)-cycloart-25-ene-3beta, 24-diol (24b); one triterpene saponin: 3-O-[alpha-rhamnopyranosyl (1→2)-beta-galactopyranosyl (1→2)-beta-glucuronopyranosyl] soyasapogenol B (soyasaponin I) (53); three phytosterols: beta-sitosterol (17), stigmasterol (18), and daucosterol (47); sixteen isoflavanones and O-glycosides: 5, 7-dihydroxy-2', 4'-dimethoxy-isofavanone (homoferreirin) (22), 5, 7, 4'-trihydroxy-2'-methoxy-isofavanone (isoferreirin) (23), (3R)-5, 7-dihydroxy-2', 3', 4'-trimethoxy-isoflavanone (25a), (3S)-5, 7-dihydroxy-2', 3', 4'-trimethoxy-isoflavanone (25b), (3R)-5, 7-dihydroxy-2'-methoxy-3', 4'-methylenedioxy-isoflavanone (26a), (3S)-5, 7-dihydroxy-2'-methoxy-3, 4'-methylenedioxy-isoflavanone (26b), 5, 7, 3'-trihydroxy-2', 4'-dimethoxy-isoflavanone (secundiflorol H) (40), 5, 7, 2', 4'-tetrahydroxy-isoflavanone (dalbergiodin) (41), 3, 5, 7, 4'-tetrahydroxy-2, 2'-epoxyisoflavanone (42), (3R)-5, 7-dihydroxy-2', 3', 4'-trimethoxy-isoflavanone 7-O-beta-glucopyranoside (48a), (3S)-5, 7-dihydroxy-2, 3', 4'-trimethoxy-isoflavanone 7-O-beta-glucopyranoside (48b), (3R)-5, 7-dihydroxy-2'-methoxy-3', 4'-methylenedioxy-isofavanone 7-O-beta-(glucopyranoside (49a). (Abstract shortened by UMI.) / In the present study, two medicinal plants were investigated for their organic constituents. Plant samples were extracted and purified by chromatographic separation using a combination of methods. Each compound isolated was characterized by spectroscopic and physical data. A number of new chemical structures were found. / The investigation has led to the isolation and structural elucidation of fourteen pure compounds from an ethanol extract prepared from the dried rhizomes of Alisa orientale, including three types of skeletons: protostane triterpene, guaiane sesquiterpene and phytosterol. They were identified to be beta-sitosterol (1), (17S)-3, 11-dioxo-23-nor protost-12-en-23 (17)-olide (2), alisol B 23-acetate (3), alismol ( 4), alismoxide (5), alisol B (6), alisol A (7), 25-O-methylalisol A (8), 25-anhydroalisol A 24-acetate (9), 25-anhydroalisol A (10), alisol E 23-acetate (11), daucosterol 6'-stearate (12), (20R, 23S, 24R)-23, 24, 25-trihydroxy-2, 3-seco protost-13 (17)-en-3-oic acid 2, 11beta-lactone (13), and 13beta, 17beta-epoxyalisol A (14). Among them, compound 2 was a new naturally occurring skeleton of 23-nor protostane triterpene, and compound 13 a new 2, 3-seco-protostane triterpene. / Zhao Ming. / "September 2005." / Adviser: Chun-Tao Che. / Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3812. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 179-187). / 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, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.
47

Pharmacognostical study of lycium species

Peng, Yong 01 January 2005 (has links)
No description available.
48

Enantioselective total synthesis of (-)-16-hydroxytriptolide

Lui, Bob. January 2005 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.
49

Assessing ethnobotanical knowledge and resources to develop a sustainable management plan for the Lokaro Reserve in southeast, Madagascar

Lehman, Ashley Davis. January 2009 (has links)
Thesis (MS)--University of Montana, 2009. / Contents viewed January 14, 2010. Title from author supplied metadata. Includes bibliographical references.
50

Iranian medicinal plants and antiparasitic compounds : from ethnobotany to contemporary scientific evidence /

Sairafianpour, Majid. January 2002 (has links)
Ph.d.

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