Isolation of secondary metabolites derived from marine bacteria in Jeju island, Korea and their biological activities

Abstract

In order to explore marine microorganisms with medical potential, we tried to isolate and identify the marine-derived bacteria from four types of marine samples including float, marine algae, animal, and sponge collected from Jeju Island, Korea. Finally, 21 different strains have been successfully isolated and identified from these samples by 16S rRNA analysis. Then, all strains were cultured in the Marine Broth and were extracted with ethyl acetate, were assessed in a series of bioassays. The results of these assays showed that four extracts inhibited DPPH by more than 50%, four extracts inhibited hydrogen peroxide by greater than 50%, one extract inhibited the growth of HL-60 cells by more than 95%, 14 extracts inhibited nitric oxide production more than 50% and 12 of them without cytotoxicity in LPS-induced RAW 264.7 cells. These data revealed the tested samples to have many and varied activities, Moreover, the large number of samples demonstrating activity in only one or sometimes two assays accentuates the potential of the bacterial strains isolated from marine-derived samples could be the good sources for biological natural products.