Résumé
Symbiotic association between marine sponge and microorganism was a promising chance in the discovery of leadcompound of anticancer. This association was probably concluded that symbiotic microorganism would contain thesame secondary metabolites with the host. In this continuation research, we had isolated symbiotic bacteria from amarine sponge and tested for cytotoxic activity. Twenty-six isolates of bacteria derived from marine sponge Haliclonafascigera were isolated from Setan Island, West Sumatra, Indonesia. Screening of cytotoxic activity by BSLT methodand MTT assay was conducted toward 21 ethyl acetate extracts of symbiotic bacteria with weight >50 mg. Onebacterial extract with code H2N was very toxic according to BSLT test, while 18 isolates were toxic with LC50 rangingfrom 31.17 to 283.38 ppm. All of the bacterial extracts did not show a good percentage of viability (>50%) againstHela, WiDr, T47D, dan Vero cell line in MTT assay. However, bacterial extract with code H2N have shown potentialcytotoxic compared to other extracts. As per the phytochemical study, this extract probably contained terpenoid group.Based on biochemical examination this bacterium, H2N, was identified as Bacillus sp.3.