DOI: 10.36347/sjavs.2018.v05i04.002

Pages: 191-198

Abstract: Proteases are important enzymes and have high economic value due to their wide applications in the food industry as a meat tenderizer. Protease use in the food industry necessitates an understanding of the capabilities and influencing factors of these enzymes to accelerate enzymatic reactions. This study aims to isolate and characterize the proteases of lactic acid bacteria (LAB) from Bekasam. The samples were obtained from the third, fifth, seventh, ninth and eleventh day of fermentation to isolate the proteolytic LAB. Characterization of proteases includes the casein substrate concentration, optimum temperature and pH, and the effect of some metal ions as activators or inhibitors of the protease enzyme activity measured with a spectrophotometer at λ 280 nm. The LAB with the highest protease activity is identified molecularly and isolate through 16S rDNA sequencing and phylogenetic analysis based on the Neighbor Joining method. The results showed that the best isolate was BAF-715 because it had the highest protease activity of 18.84 U/ml at 40 hours of incubation. The optimum activity of this protease on a casein substrate at 2.5% occurred at an incubation temperature of 40 °Cat pH 7 and in the presence of Mg2+ and Mn2+ (5 mM) as activators. Based on molecular DNA identification, the BAF-715 isolate is determined to be Pediococcus pentosaceus. It was concluded that a protease produced by Pediococcus pentosaceus showed the highest proteolytic activity.