African Journal of

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12485

Full Length Research Paper

Screening extracts of fungal endophytes isolated from Allophylus abyssinicus (Hochst. Radlk.) for control of bean anthracnose

Hellen Gathiru Kariuki
  • Hellen Gathiru Kariuki
  • Department of Biological Sciences, Egerton University, Njoro, Nakuru County, Kenya.
  • Google Scholar
Isabel Nyokabi Wagara
  • Isabel Nyokabi Wagara
  • Department of Biological Sciences, Egerton University, Njoro, Nakuru County, Kenya.
  • Google Scholar
Beatrice Were
  • Beatrice Were
  • Department of Biological Sciences, University of Eldoret, P. O. Box 1125-30100, Eldoret, Kenya.
  • Google Scholar
Waudo Walyambillah
  • Waudo Walyambillah
  • Department of Chemistry, Jomo Kenyatta University of Agriculture and Technology, P. O. Box 62000-00200, Nairobi, Kenya.
  • Google Scholar
Josphat Clement Matasyoh
  • Josphat Clement Matasyoh
  • Department of Chemistry, Egerton University, P. O. Box 536-20115, Egerton, Kenya.
  • Google Scholar

  •  Received: 28 March 2023
  •  Accepted: 01 June 2023
  •  Published: 31 October 2023


Common bean is consumed in large quantities globally but it is highly susceptible to Colletotrichum lindemuthianum, leading to 90 to 100% yield losses. This study investigated the bioactivity of secondary metabolites from Allophylus abyssinicus fungal endophytes against C. lindemuthianum, causing bean anthracnose. A total of 37 fungal endophytes were isolated from the leaves, bark and roots of A. abyssinicus and 20% identified by ITS-rDNA sequence analysis as Aspergillus hancockii, Penicillium christenseniae, Penicillium atrosanguineum and Penicillium manginii. Thirty-three of the endophytes were active against C. lindemuthianum in the dual culture assay with the highest inhibition being 82.6% (A. hancockii). Two of the most active endophytes (A. hancockii and P. christenseniae) were fermented on rice media and their methanol extracts partitioned between ethyl acetate and hexane. Aspergillus hancockii crude hexane extract had the highest inhibition (19.0±1.7mm at 100 mg/ml) against the pathogen under the bioassay screening and 6.3±3.8 mm at 6.25% against C. lindemuthianum under the minimum inhibitory concentration (0.625 mg/ml) screening. Chemical screening of the extracts revealed presence of alkaloids in A. hancockii and P. christenseniae; sterols, triterpenes and coumarins in A. hancockii. These results indicated that fungal endophytes from A. abyssinicus are a source of active compounds that can be used to control C. lindemuthianum affecting common bean.


Key words: Allophylus abyssinicus, Antifungal activity, Colletotrichum lindemuthianum, fungal endophytes, secondary metabolites.