Antimicrobial Activities of Fungus Comb Extracts Isolated From Indo-Malayan Termite Macrotermes Gilvus Mound

The embodiment of antimicrobial components into the food packaging material has the ability to prevent microbial contamination. Fungus comb could be an alternative source of natural antimicrobial agents. In this study, n-hexane, ethyl acetate, methanol, and water extracts from fungus comb isolated from Indo-malayan termite Macrotermes gilvus Hagen mound were analysed for its antibacterial and antifungal activities against food spoilage microorganisms, including Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923, Aspergillus flavus, and Aspergillus niger. The antimicrobial activity of the fungus comb extracts was evaluated using Kirby-Bauer disc diffusion and microdilution method. The result showed that ethyl acetate extract exhibited the biggest diameter inhibition zone for all bacteria and fungi tested. Ethyl acetate extract showed antibacterial activity in all bacteria with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 0.39 mg/mL and 0.78 mg/mL, respectively. This extract also inhibited A. flavus and A. niger with MIC value of 0.78 mg/ml. Ethyl acetate extract contained guaiacol and syringol, which were predicted as the main antimicrobial components in fungus comb. Whereas n-hexane extract only inhibited Gram-positive bacteria. S. aureus ATCC 25923 was the most sensitive bacteria tested using all extracts. In addition, A. flavus was more sensitive compared to A. niger. Overall, fungus comb extract exhibited antimicrobial activity against E.coli ATCC 25922, P. aeruginosa ATCC 27853, S. aureus ATCC 25923, A. flavus, and A. niger. This study revealed that the fungus comb extract, especially ethyl acetate, could be considered as a new antimicrobial agent.