Comparative analysis of bioactive compounds and antibacterial activities of crude skin extracts from surma fish (Rastrelliger kanagurta) and Lal Poa Fish (Chrysochir aureus)

Abstract

Fish skin, considered a waste product in the fisheries industry, is a potential source of various bioactive compounds with antibacterial properties. In this study, we investigated the bioactive compounds and antibacterial activities of 50% ethanolic crude skin extracts from Rastrelliger kanagurta (Surma fish) and Chrysochir aureus (Lal poa fish). Qualitative screening showed the presence of alkaloids, terpenoids, saponins, and phenolic compounds with differences between the two fish species. Antibacterial activity was evaluated against Staphylococcus aureus, Klebsiella spp., and E. coli, using the agar well diffusion method at concentrations of 25 and 50 mg/mL. At higher concentration, Surma fish extract showed partially active antibacterial activity against Klebsiella spp., and E. coli, but Lal poa fish showed partially active against E. coli bacterial strain at both concentrations, possibly due to its higher phenolic content. These results indicated that fish skin could serve as a potential source of natural antibacterial agents.

J. Bangladesh Acad. Sci. 50(3); 499–505: September 2026