Activities of amylase, proteinase, and lipase enzymes from Lactococcus chungangensis and its application in dairy products

Abstract

Several enzymes are involved in the process of converting milk to lactic acid and coagulated milk to curd and, therefore, are important in dairy fermented products. Amylase, proteinase, and lipase are enzymes that play an important role in degrading milk into monomeric molecules such as oligosaccharides, amino acids, and fatty acids, which are the main molecules responsible for flavors in cheese. In the current study, we determined the amylase, proteinase, and lipase activities of Lactococcus chungangensis CAU 28(T), a bacterial strain of nondairy origin, and compared them with those of the reference strain, Lactococcus lactis ssp. lactis KCTC 3769(T), which is commonly used in the dairy industry. Lactococcus chungangensis CAU 28(T) and L. lactis ssp. lactis KCTC 3769(T) were both found to have amylase, proteinase, and lipase activities in broth culture, cream cheese, and yogurt. Notably, the proteinase and lipase activities of L. chungangensis CAU 28(T) were higher than those of L. lactis ssp. lactis KCTC 3769(T), with proteinase activity of 10.50 U/mL in tryptic soy broth and 8.64 U/mL in cream cheese, and lipase activity of 100 U/mL of tryptic soy broth, and 100 U/mL of cream cheese. In contrast, the amylase activity was low, with 5.28 U/mL in tryptic soy broth and 8.86 U/mL in cream cheese. These enzyme activities in L. chungangensis CAU 28(T) suggest that this strain has potential to be used for manufacturing dairy fermented products, even though the strain is of nondairy origin.

Investigation of the Lactic Acid Bacteria in Kazak Cheese and Their Contributions to Cheese Fermentation

“…The qualitative evaluation of lipase activity of all strains was determined on MRS agar plates prepared with 10% tributyrin (Yuanye Biotechnology Co., Ltd.), and the formation of a transparent halo on the plate indicated that the microorganisms metabolized the lipids. Lipase activity was measured by potentiometric titration with an indicator (Konkit and Kim, 2016).…”

“…Lactic acid bacteria can be used as a starter culture for cheese fermentation because of their ability to release proteases, lipases, or β-galactosidases to form a unique taste, aroma, and texture (Juan et al, 2016). During cheese fermentation, the most important features and functions of LABs are (1) the conversion of lactose in milk into small molecular monosaccharides, galactose, and glucose, which promote the formation of cheese flavor (Blaya et al, 2018); (2) the degradation of proteins into peptides and free amino acids (FAAs) in cheese; and (3) the decomposition of lipids into fatty acids (Konkit and Kim, 2016). Proteases are key enzymes in the hydrolysis of protein during cheese fermentation.…”

Selection of Lactic Acid Bacteria Isolated from Fresh Fruits and Vegetables Based on Their Antimicrobial and Enzymatic Activities

“…Vegetable samples collected were a good source of presumptive LAB isolates with important enzymatic activities, which can influence a food product with enhanced flavor, texture, or nutritional features. Additionally, these enzymatic properties can be used in the production of substances with industrial importance, such as lactic acid and diacetyl [ 18 , 38 ] or for the production of enzymes to be used at an industrial scale, such as amylase [ 17 , 18 ]. The LAB isolates selected bases on their enzymatic activity were also identified by molecular techniques.…”

“…LAB can also be a source of novel strains with enzymatic activities of interest for food production or other industrial use of enzymes [ 16 , 17 ]. Enzymes of microbial origin are more desirable than enzymes from other sources as they may show enhanced catalytic activities, present higher yields, and economic culture media can be used in microbial growth.…”

“…Enzymes of microbial origin are more desirable than enzymes from other sources as they may show enhanced catalytic activities, present higher yields, and economic culture media can be used in microbial growth. The primary enzymes employed for food production include amylases, proteases, and lipases [ 17 ]. Amylase [ 18 ], citrate lyase [ 19 ], and protease [ 11 , 14 ] activities have been previously reported in LAB isolated from vegetable sources.…”