ANTIBACTERIAL AND ANTIFOULING POTENCY OF Xestospongia testudinaria EXTRACTS FROM BADI ISLAND, SPERMONDE ARCHIPELAGO

The Sponge Xestospongia testudinaria belongs to the genus Xestospongia and produces various potential secondary metabolites. These secondary metabolites have been found to have potential antibacterial and antifouling compounds. The study aims to determine the antibacterial and antifouling potency of sponge X. testudinaria, using phytochemical and FTIR data as supporting data. Thick green extracts were used for screening antibacterial and antifouling tests. Samples with ration 1:4 w/v were macerated using n-hexane, ethyl acetate, and acetone for 3 x 24 h. The diffusion agar method was used to test antibacterial activities against Vibrio sp. and marine fouling bacteria. This study demonstrated the moderate potency of X. testudinaria extracts as antibacterial agents against Vibrio sp. The ethyl acetate crude extract of sponge X. testudinaria provided the highest inhibition zone against Vibrio harveyi (12.19 mm) at a concentration of 2 μg/25 μL. Moreover, an ethyl acetate extract with an average inhibition zone of 13.60 mm indicated the highest antifouling assay using agar diffusion. Meanwhile, phytochemical screening and FTIR were performed in the extract's presence of steroids, terpenoids, and alkaloids. In conclusion, the ethyl acetate extract of X. testudinaria can be one of the candidates for antibacterial drugs against Vibrio sp. and makes them very promising candidates for eco-friendly antifouling with further and comprehensive tests.