Essential oil composition and some biological activities of tetradenia riparia
| dc.contributor.advisor | Oyedeji, A.O. | |
| dc.contributor.advisor | Opoku, A.R. | |
| dc.contributor.advisor | Lewu, F.B. | |
| dc.contributor.author | Khuzwayo, Joyce Khethiwe | |
| dc.date.accessioned | 2012-08-02T08:15:07Z | |
| dc.date.available | 2012-08-02T08:15:07Z | |
| dc.date.issued | 2011 | |
| dc.description | A dissertation submitted to the Department of Chemistry, Faculty of Science and Agriculture in partial fulfilment of the requirement for Masters Degree in Chemistry, South Africa, 2011. | en_US |
| dc.description.abstract | This dissertation has a brief historical overview of medicinal plants, T. riparia and their traditional uses. The choice of the medicinal plant studied was based on the evidence in literature that oils of the species contain phenolic compounds and the herbs belonging to the family Lamiaceae was implicated in the management of chronic and infectious diseases. The study was designed to determine the secondary metabolites present in the plant through phytochemical screening of the plant material, establish the chemical profile of the isolated oils using GC-MS and evaluate the biological potential of both the crude extracts and the isolated oils which included; antioxidant, antibacterial and anti-ulcer activities. The essential oils were extracted from the dry stem and fresh leaves of T. riparia. Farnesol, caryophyllene oxide, -fenchyl acetate, and guaiol (12.3 - 7.1%) were the most prominent compounds identified in the dry stem oil collected from the botanic garden, Botany Department, University of Zululand (UZ). The analysis of the fresh leaf oil from the botanic garden collection had hexane as the major compound (60.9%), while -fenchyl acetate (6.7%), caryophyllene oxide (4.1%) and farnesol (2.5%) were other prominent components present in the oil. The dry stem oil from Maphumulo had farnesol (27.4%), humulene oxide (11.5%), -eudesmol (8.9%), caryophyllene oxide (3.8%) and terpinene-4-ol (3.35) as the main components, while the fresh leaf oil composition from Maphumulo was similar to that of botanic garden with hexane accounting for over 50% of the oil composition. Other prominent compounds identified in the GC-MS analysis of the fresh leaf oil were farnesol (6.3%) and a-thujone (3.6%). The chemical profiles of the T. riparia plant samples collected from two difference location within the KwaZulu-Natal suggest two distinct chemotypes of the plant species. Nonetheless, farnesol was found to be the major constituents of all the oils parts isolated. To the best of my literature knowledge and search, this is the first time that the chemical composition of the essential oils isolated from the leaf and stem of T. riparia is been reported. The phytochemical screening of the plant reveals saponins (23.3%), flavoinoids (3.7-4.9%) and tannins (4.1%) to be prominent secondary metabolites presence. These compounds are known to exhibit anti-ulcer activities. Indeed, a 65% inhibition of indomethacin-induced gastric ulceration was observed for the plants essential oil. The antibacterial activity studies indicated that the oil had moderate inhibitory effect on most of the bacteria. Zones of inhibition, from the disc diffusion assay of the essential oil, ranged from 6.3- 19.3 mm. The minimum inhibitory concentration (MIC) value of 0.157 mg/ml was recorded for the dry stem oil extracts from Maphumulo. The results from the biological assays showed that there is good correlation with the traditional usage of T. riparia. The results are explained fully in the body of the dissertation. The limitation for this work is that the isolation of essential oil compounds using Preparative GC was not possible as the equipment though available was not functional due to some technical unresolved issues. | en_US |
| dc.description.sponsorship | NRF | en_US |
| dc.identifier.uri | https://hdl.handle.net/10530/1094 | |
| dc.language.iso | en | en_US |
| dc.publisher | University of Zululand | en_US |
| dc.subject | Medicinal plants -- traditional uses. | en_US |
| dc.subject | Oil composition | en_US |
| dc.title | Essential oil composition and some biological activities of tetradenia riparia | en_US |
| dc.type | Thesis | en_US |