Purification and biochemical characteristics of the protease from Lactobacillus brevis R4 isolated from Harbin dry sausages

This study investigated the purification and biochemical characteristics of the protease secreted by Lactobacillus brevis R4 that was isolated from Harbin dry sausages. The optimized fermentation conditions were a fermentation time of 36 h, an initial pH of 5 and a fermentation temperature of 42 °C. A 27.9 kDa extracellular protease was purified using ammonium sulfate precipitation, ion exchange layer and gel filtration and was determined by...