PROTEOLYTIC FUNGI FROM VIRGIN FOREST

Abstract

Microbial enzymes have continued to assist diverse reactions as biocatalysts. Soil derived microbes offer a prospective resource for such enzymes. Screening and isolation of proteolytic fungi were carried out from soil sample of a Malaysian virgin forest. Four isolates showed clear zone of protein hydrolysis on skim milk agar representing proteolytic activity. Aspergillus flavus UOA/HCPF 5774 exhibited the highest proteolytic activity with a clear zone diameter of 21 mm followed by Aspergillus niger and Trichoderma harzianum both with a clear zone of 16 mm, and Penicillium simplicissimum strain LP42 with a13 mm clear zone. Crude protease activity of 0.230 – 0.277 Units / ml for each fungus was seen after 24 hours incubation. A decline of protease production was observed after 48 hours incubation except for Aspergillus flavus UOA/HCPF 5774 which showed a drop only after 72 hours incubation. The protease producing fungi were partially identified based on their morphological characteristics, macroscopic and microscopic identification. The identification was confirmed by 18S rRNA Sequence Analysis. The four fungi protease producers were Aspergillus niger, Penicillium simplicissimum strain LP42, Aspergillus flavus UOA/HCPF 5774 and Trichoderma harzianum.