Selection of lactic acid bacteria as a protease enzyme producer

Abstract

Melliawati R, Djohan AC, Yopi. 2015. Selection of lactic acid bacteria as a protease enzyme producer. Pros Sem Nas Masy Biodiv Indon 1 (2): 184-188. Selection of lactic acid bacteria producing protease enzyme from the BTCC collection was conducted from buttermilk and danke. Selection medium used MRSA + CaCO3 0.5%, skim milk agar (SMA) medium and pasteurized milk. The result showed that of 42 isolates tested, 36 isolates produced lactic acid, and 20 isolates of the lactic acid producing isolates showed clear zone index ≥ 2. Meanwhile, the proteolytic test resulted in 18 isolates that were able to hydrolyze protein, and 8 isolates of the hydrolyzing protein isolates showed clear zone index above 1.6. Among the tested bacteria, isolate DR 1-3-2 (Lactobacillus plantaruum LAB12 strain) exhibited the highest activity of protease enzyme, up to 0,598 units/mL during 72-hour fermentation. Media optimization and environmental factors need to be controlled to maximize the enzyme activity.