Preliminary Evaluation of Lake Lanao fish Hypseleotris agilis Herre for Antimicrobial Activity

Abstract

The search for bioactive compounds from a variety of living organisms as alternative source of cure is a relentless effort of man to fight various diseases. Recently, natural products from freshwater fish have been exploited. Hence this study was conducted primarily to tap the dominating invasive fish species Hypseleotris agilis Herre of Lake Lanao, Philippines as possible source of indigenous drugs. The fish is locally known as Katulong belonging to the family Eleotridae which believed to have been accidentally introduced sometime in the 1960s along with tilapia and milkfish fry stocking in the lake for aquaculture. This preliminary study specifically aimed to evaluate the antibacterial and antifungal potentials of the freshwater fish. Crude methanol extract of the whole fish were assayed for antimicrobial activity using the filter paper disc diffusion assay against one fungal strain Candida albicans, two Gram-negative bacterial strains Pseudomonas aeruginosa and Escherichia coli and two Gram-positive strains Staphylococcus aureus and Bacillus subtilis. As shown in the measured zones of inhibition, the fish extract significantly inhibited the growth of S. aureus, B. subtilis, and P. aeruginosa but not the C. albicans and E. coli and. Results indicated the potential of the fish as source of natural products with antibacterial properties.