An endophytic fungus, Aspergillus flavus IBRL-C8 was isolated from leaf of a medicinal plant Cassia siamea Lamk. This isolated fungus was cultivated in yeast extract sucrose broth medium with the addition of host plant water extract and incubated at 30°C with 120 rpm of agitation speed for 20 days. After the incubation period, the fermentative broth medium which contained the extracellular compounds secreted by the fungal biomass into the medium was extracted with ethyl acetate. The ethyl acetate extract showed significant zone of inhibition against Candida albicans cells. The minimal inhibitory concentration (MIC) of the extract was 1.0 mg/ml and its exhibited yeastocidal activity. The time-kill curve study was performed at three different extract concentrations (1/2MIC, MIC and 2MIC) and the results showed that the C. albicans cell growth was concentration dependent. The extract concentration lower than MIC value showed yeastostatic activity and at concentration higher than the MIC value it showed yeastocidal activity. Further detail of the effect of the ethyl acetate extract on the C. albicans cell was observed from the scanning electron microscopy (SEM) and transmission electron microscopy photomicrographs (TEM) which revealed the severity of the morphological deterioration experienced by the extract treated cells were beyond repair.
Key words: Anticandidal activity, Endophytic fungus, Cassia siamea, Minimum inhibitory concentration, Candida albican
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