ISOLASI, KARAKTERISASI DAN UJI POTENSI BAKTERIOSIN BAKTERI ASAM LAKTAT DARI UDANG

The use of synthetic preservative was aimed to inhibit food deterioration Therefore, it is necessary to look for natural and safe preservative. Bacteriocin is one of natural preservatives as a potential biopreservative agent. Asa an antibakteria. This research was aimed to isolate and select lactic acid bacteria (LAB), bacteriocin production optimization and bacteriocin purification characterization, and identifying selected isolate. Isolation of LAB was carry out from sea shrimp�s intestine. The selection was done based on qualitatively and quantitatively bacteriocin production. Selected isolate was optimized. Purification of bacteriocin with adsorption- desorption method then be continued purification step using chromatography column of ion exchange with DEAE-cellulose matrix.Characterization of purified bacteriocin included molecular weight, pH, temperature, proteolytic enzyme, pathogenic bacteria. The identification of selected isolate was based on characteristics of morphology, biochemical, physiological, and molecular (gene 16S rRNA). The result of isolation was 209 BAL isolates. Was fifty four among of them could produce bacteriocin. Based on the selections qualitatively and quantitatively, results found 8 selected isolates, one of them was SFE-7 (33) isolate which had bacteriocin activity of 72.415 Au/ml. Optimization of bacteriocin production with inoculums of 5% (v/v), source C of glucose of 20 g/l, yeast extract of source N of 20 g/l, pH of 5, temperature of 37�C, agitation velocity of 100 rpm, and time of 15 hours. , resulted in the maximum µ growth kinetics of 0.065/h, (Yb/x) 0.4 [x10 6 AU (g CDM) -1 ], (Yx/s) 62.33 [g CDM (g sugar) -1 ], (Yb/s) 50 [x 10 6 AU (g sugar) -1 ]. Extraction of bacteriocin with adsorption-desorption method resulted specific activity was 312.773 Au/ml with the level of purity 56.45 times. The result of fractionation column DEAE-cellulose was obtained the highest bacteriocin activity at the 36 th fraction that was 96.072 Au/ml, while bacteriocin specific activity was by 337.500 Au/ml with the purity level of 60.91 times., bacteriocin has molecular weight of 2.76 kDa. Characterization of purified bacteriocin showed it�s action on pH of 2-1