Potential of cellulolytic fungi isolated from the intestine of Asiatic rhinoceros beetle (Oryctes rhinoceros)

Cellulose is a potential source of fermentable sugars and a promising cost-effective source for biofuel production. This study aimed to obtain potential cellulolytic fungi from the intestine of Asiatic rhinoceros beetle (Oryctes rhinoceros L.). The cellulolytic fungi were isolated using Potato Dextrose Agar (PDA) media using spread plate method. Qualitative and quantitative screening tests were carried out using 1% of CMC (w/v) as a sole carbon source. Twelve isolates were recovered with varying cellulolytic capabilities. The highest cellulolytic activity was obtained from KOr-15J with an index of 1.93 while KOr-23J produced the lowest cellulolytic index (1.01) based on the qualitative screening. The highest cellulase activity assayed using DNS (3,5-Dinitrosalicylic acid) method revealed KOr-21J with an activity of 0.018 U/mL while three isolates (KOr-16J, KOr-19J and KOr-22J) produced the lowest activity (0.003 U/mL). This study provides multiple verifications of the potential ability of cellulolytic fungi and their cellulase activity in the intestine of Asiatic rhinoceros beetle.