PROFILING KIMIAWI DAN AKTIVITAS ANTIVIBRIO FRAKSI AKTIF HEKSANA DARI Gracilaria edulis

Infectious diseases caused by Gram-negative bacteria Vibrio spp. become an obstacle in aquaculture. The purpose of this study was to determine the anti-Vibrio activity of ethyl acetate extract of Gracilaria edulis and its fractions, as well as knowing the class of bioactive compounds with the antiVibrio activity. G. edulis was collected from the intertidal region Gunung Kidul. The seaweed were dried, extracted with ethyl acetate then screened in bioactivity from against Vibrio spp. Fractionation of active extracts were performed by the column chromatography, was silica gel as stationary phase and the mobile phase solvent, was gradient of 100% hexane to 100% ethyl acetate. The antibacterial activity experiment used the agar diffusion method, bioautografi, 6 well plate and 96 well plate. The chemistry profiling of the G. edulis was conducted by thin layer chromatography and GC-MS. The results showed that two fractions posses antibacterial activities, those were 100% and 75% hexane fraction. The MIC of the ethyl acetate extract of G. edulis and fractions active against bacteria V. fluvialis were the extract (6.25 x10-2) mg/ml, fraction 1 (6.25 x10-2) mg/ml, fraction 2 (7,81 x10-3) mg/ml, fraction 3 (1.25 x10-1) mg/ml, fraction 4 (3.125 x10-2) mg/ml. The results showed that the extract of G. edulis was bactericidal against V. fluvialis at the concentration of 1 mg/ml and bacteriostatic at concentration of 6,25x10-2 mg/ml. Fraction 2 (100% hexane) had the best activities compared to the other fractions, which were bactericidal at concentration of 5x10-1 mg/ml and bacteriostatic at concentration of 7,81x10-3 mg/ml. The GC-MS analysis showed that the compounds agent 9-hexadecenoic acid, hexadecanoic acid, 13-octadecenoic acid, 10-octadecenoic acid, eicosanoic acid, 1,2-benzenedicarboxylic acid, and cholest-8-en-3-ol. Based on these studies, G. edulis can be developed as a source of antibacterial response to combat by infection Vibrio spp. on fish farming