Isolation and characterization of antifungal compounds from actinomycetes in waste dump soil of Western Uganda

Abstract

Drug resistant and opportunistic organisms are a problem to medical health due to the fact that most of
the drugs that were used are now not effective. Currently, there is a need to search for new drugs that
can enhance the control of these organisms. Actinomycetes and their secondary metabolites can be
used as such drugs. This study was designed to isolate actinomycetes producing novel anti-fungal
compounds from waste dump soil in Western Uganda. Fifty six (56) actinomycetes were isolated from
22 waste dump soil samples. All isolates were screened using modified spektra - plak method against
Candida albicans ATCC1023, Penicillium sp., Aspergillus sp., Fusarium sp. and Rhizopus sp. Eight
8(14.29%) isolates showed antifungal activity to at least one test fungi during primary screening. Two
isolates [KBRWDSa (FR) and KBMWDSb6] showed activity to all test fungi. Secondary screening was
carried out by growing all 56 isolates in broth and their supernatant was tested for antifungal activity
using agar well diffusion method. 11(19.64%) of these isolates showed activity against at least one test
fungi with mean zone of inhibition 5.33 to 29.69 mm. Isolate KBMWDSb6 showed a broad spectrum
activity against all test fungi. The remaining broths were extracted using ethanol. The ethanol extract at
2.5 mg/ml concentration was also tested for antifungal activity using agar well diffusion method. 13
(23.21%) isolates showed activity against at least one test fungi with mean zone of inhibition 6.33 to
30.67mm. The findings showed that some of these isolates had antifungal activity.