- Title
- Chemical analysis of selected Eastern Cape medicinal plants
- Creator
- Mahanjana, Lungelwa
- Subject
- Medicinal plants -- South Africa --Eastern Cape
- Subject
- Traditional medicine --South Africa -- Eastern Cape Maps
- Date Issued
- 2022-04
- Date
- 2022-04
- Type
- Doctoral theses
- Type
- text
- Identifier
- http://hdl.handle.net/10948/55976
- Identifier
- vital:54560
- Description
- In the rural parts of the Eastern Cape Province of South Africa, the use of medicinal plants to treat or manage diseases, including those associated with diabetes and HIV, is a common practice. However, the phytochemistry, safety and efficacy of these medicinal plants remain less investigated. Based on available traditional medicinal knowledge (through traditional healers, university library resources, ethnobotanical and science journals and other internet resources), traditional uses and availability, three plant species, namely Bulbine latifolia L. Wild, Dicerothamnus rhinocerotis Koek. and Olea europaea subsp. africana (Mill.) P.S. Green were selected and investigated for their hytoconstituents and biological effects. Phytochemical screening of the three medicinal plants was carried out quantitatively and qualitatively using spectrophotometric methods. Chemical profiling of the crude methanol extracts of all the plant species was successfully done by high-performance thin layer chromatography (HPTLC) and tentative identification of the secondary metabolites was achieved by liquid chromatography–mass spectrometry (LCMS). Cytotoxicity effect investigations on the crude extracts of the three species was done using the 3-[4,5- dimethylthiazole-2-yl]-2,5- hiphenyltetrazolium bromide (MTT) assay against HeLa cervical cancer cells. Isolation and purification of single compounds was done using chromatographic techniques (column chromatography (CC), and preparative thin-layer chromatography (PTLC)). Characterisation of single compounds was achieved using spectroscopic techniques such as Nuclear Magnetic Resonance (NMR), High Resolution Mass Spectrometry (HRMS), Ultra Violet Spectroscopy (UV-vis), Fourier-Transformed Infra-Red Spectroscopy (FTIR) and Single-Crystal X-ray Diffraction (XRD). For the first time from the methanol crude extract of the tubers of B. latifolia, the crystal structure of the phenylanthraquinone, knipholone (3.12) (1-(3-acetyl-2,6- dihydroxy-4- methoxyphenyl)-4,5-dihydroxy-2-methylanthraquinone), was isolated and elucidated along with its derivatives, isoknipholone (3.14), knipholone-6’-methyl (3.27). Moreover, two new compounds, (M)-8-O-β-D-glucopyranosyl-10’-α-L-rhamnopyranosyl-1,1',8',10'-tetrahydroxy 3,3'-dimethyl-[10,7'-bianthracene]-4,9,9'(10'H)-trione (3.23a) and (P)- 8-O-β-D glucopyranosyl-10’-α-L-rhamnopyranosyl-1,1',8',10'-tetrahydroxy-3,3'-dimethyl-[10,7'- bianthracene]-4,9,9'(10'H)-trione (3.23b) were isolated.
- Description
- Thesis (PhD) -- Faculty of Science, School of Biomecular and Chemical Sciences, 2022
- Format
- computer
- Format
- online resource
- Format
- application/pdf
- Format
- 1 online resource (xxv,251 pages)
- Format
- Publisher
- Nelson Mandela University
- Publisher
- Faculty of Science
- Language
- English
- Rights
- Nelson Mandela University
- Rights
- All Rights Reserved
- Rights
- Open Access
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| Thumbnail | File | Description | Size | Format | |||
|---|---|---|---|---|---|---|---|
| View Details Download | SOURCE1 | Mahanjana, L.pdf | 8 MB | Adobe Acrobat PDF | View Details Download |