By Ahmad Ni'matullah Al-Baarri
Recently, bio-preservative is being developed rapidly as a food preservative method due to meet food safety and consumer demand. Natural compound such as lysozyme, lactoferrin, nisin, glucose oxidase, and lactoperoxidase, is now highlighted because of its antimicrobial function. Among those milk-purified compound, lactoperoxidase seem highest potential and wide ranged scope in application on food industry.
Lactoperoxidase (LPO) is a naturally existing enzyme in raw milk, catalyses the chemical reaction of thiocyanate, resulting intermediary product OSCN- which has function as a bacteriostatic and bactericidal agent. Growth of single strains of the pathogens such as Staphylococcus sp., Listeria sp., E, coli, Salmonella sp., Yersinia enterocolitica, Pseudomonas, and other possible microorganism naturally occur in vegetable, meat, and other animal products can be killed or inhibited by this system products. The anti-bacterial properties of the LPOs are generally recognized as safe (GRAS) status has resulted in numerous publications suggesting its use as a natural food preservative.
LPO consists of a single polypeptide chain containing 612 amino acid residues and its molecular weight is about 85 kDa. It contains 15 half-cystine residues and carbohydrate moieties that comprise about 10% of the weight of the molecule. LPO enzyme can be purified and characterized from different sources, such as bovine, llama, buffalo, camel, cows, mice milk.
