African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5128

Full Length Research Paper

Isolation and characterization of Streptomyces species with antifungal activity from selected national parks in Kenya

James Oluoch Nonoh1,2, Wilber Lwande1, Daniel Masiga1, Rafi Herrmann4, James K. Presnail4, Eric Schepers4, Matilda Angela Okech1, Richard Bagine3, Paul Mungai3, Aggrey Bernard Nyende2 and Hamadi Iddi Boga2*
  1International Center of Insect Physiology and Ecology (ICIPE), P.O. Box 30772 –00100, Nairobi, Kenya. 2Botany Department, Jomo Kenyatta University of Agriculture and Technology (JKUAT), P.O. Box 62000 (00200), Nairobi, Kenya. 3Kenya Wildlife Service (KWS), P.O. Box 40241-00100, Nairobi, Kenya. 4Pioneer, A DuPont Company, Crop Genetics Research and Development, Rte 141 & Henry clay rd. Wilmington, DE 19880.
Email: [email protected]

  •  Accepted: 15 April 2010
  •  Published: 04 May 2010

Abstract

 

Microorganisms and their natural products are potentially important for the biological control of crop diseases without detrimental effects to the environment. In this study, acetonitrile-methanol extracts of 361 actinobacterial isolates obtained from Aberdares, Arabuko Sokoke, Lake Bogoria, Mt Kenya, Kakamega, Ruma, Shimba Hills and Imenti forest national parks in Kenya were screened for antagonism against Fusarium oxysporumFusarium spp and Colletotrichum kahawae, which are important crop pathogens. Twenty-three isolates showed antagonistic activity to one or all of the test fungi. Five isolates that were antagonistic against all test fungi were investigated further and were also found to have antibacterial activity against Staphylococcus aureus and Escherichia coli. Morphological and physiological studies show that the isolates belong to streptomycetes. Phylogenetic analysis of amplified actinobacterial 16S rRNA gene confirmed that all the five antagonistic isolates formed close phylogenetic clusters with known members of Streptomyces species with a (97 - 100%) sequence identity. The results suggest that protected areas may be ideal habitats for isolation of antagonistic actinobacterial species which may have the potential for beneficial application in biological control of fungal pathogens. However, further investigation by characterization of the antifungal and antibacterial compounds produced will be necessary.

 

Key words: Protected areas, soil streptomyces, bio-prospecting, antimicrobial, phytopathogens.