Biological and chemical characterisation of marine streptomycetes active against selected pathogenic yeasts / Mumtaz Hidayahtullah bt Atau @ Yatau

Atau @ Yatau, Mumtaz Hidayahtullah (2012) Biological and chemical characterisation of marine streptomycetes active against selected pathogenic yeasts / Mumtaz Hidayahtullah bt Atau @ Yatau. Masters thesis, University of Malaya.

[img]
Preview
PDF
Download (3596b) | Preview
    [img]
    Preview
    PDF (Full Text)
    Download (3809b) | Preview
      [img]
      Preview
      PDF
      Download (122Kb) | Preview
        [img]
        Preview
        PDF
        Download (22Kb) | Preview
          [img]
          Preview
          PDF
          Download (395Kb) | Preview
            [img]
            Preview
            PDF
            Download (131Kb) | Preview
              [img]
              Preview
              PDF
              Download (8Mb) | Preview
                [img]
                Preview
                PDF
                Download (1615Kb) | Preview
                  [img]
                  Preview
                  PDF
                  Download (143Kb) | Preview
                    [img]
                    Preview
                    PDF
                    Download (3156Kb) | Preview

                      Abstract

                      Streptomyces spp. have been the most abundant sources of all types of antibiotics. The success of marine natural products has promoted the marine environment as a source of novel chemical diversity for drug discovery. In Malaysia, the marine actinomycetes niche remains virtually unexplored and is a promising resource for the biotechnological applications including drug discovery. Screening for antifungal activity revealed that six out of 44 putative Streptomyces spp. isolated from sponges from Tioman Island showed strong antifungal activities against Candida albicans and Schizosaccharomyces pombe. Some physiological characterisation was done to these six potential strains to facilitate the strain identification including temperature range and optimum temperature range for growth, formation of melanoid pigment, liquefaction of gelatin, hydrolysis of starch, hydrogen sulfide production, sodium chloride tolerance, carbon sources utilization,nitrate reduction test and pH sensitivity. Fermentation of these strains was done using ISP 2 broth as growth medium prior to extraction of their bioactive components using ethyl acetate in ratio of 3:1 (filtrate broth: ethyl acetate). The crude extract of the strains were analysed using high performance liquid chromatography (HPLC) for chemical profiling. Based on the HPLC analysis, interesting compounds in three strains (X34, X42 and X77) were detected. 16S rRNA gene sequence analysis of these three strains showed 100%, 99.70% and 99.76% similarity to Streptomyces rochei (strain X34), Streptomyces albidoflavus (strain X42) and Streptomyces cavourensis (strain X77), respectively. When crude extracts of these three strains were tested against S. pombe, only strain X34 was positive and was further profiled, purified and isolated by column chromatography, thin layer chromatography (TLC), HPLC and preparative thin layer chromatography (PTLC). Six fractions (F1-F6) were obtained after column chromatography was done to strain X34, and were tested against S. pombe. As only iv fraction F5 was positive, this fraction was subjected to PTLC. Another six sub-fractions (F5.1-F5.6) obtained after PTLC (of fraction F5) which were then tested against S. pombe. As a result, two out of six sub-fractions (F5.1 and F5.4) showed antifungal activity against the tested fungi but based on their 1H-NMR chromatogram, only subfraction F5.1 was further analysed by nuclear magnetic resonance (NMR) and fourier transformation infrared spectroscopy (FTIR) for structure identification. Both NMR and FTIR analyses showed that the active sub-fraction (F5.1) was belonging to 2-(3- hydroxybutan-2-yloxy) propanoic acid. This is the first report of antifungal activity of this compound isolated from Streptomyces rochei.

                      Item Type: Thesis (Masters)
                      Additional Information: Dissertation (M.Sc.) -- Institut Sains Biologi, Fakulti Sains, Universiti Malaya, 2012
                      Uncontrolled Keywords: Marine streptomycetes; Pathogenic yeasts
                      Subjects: Q Science > Q Science (General)
                      Q Science > QH Natural history
                      Divisions: Faculty of Science
                      Depositing User: Miss Dashini Harikrishnan
                      Date Deposited: 14 Oct 2014 10:18
                      Last Modified: 14 Oct 2014 10:18
                      URI: http://studentsrepo.um.edu.my/id/eprint/4191

                      Actions (For repository staff only : Login required)

                      View Item