LASSIFICATION AND CONFIRMATION OF ANTIMICROBIAL ACTIVITY OF A FOOD PEPTIDE IN AN IN VITRO EXPERIMENT

ZQMDEG

Abstract

Peptides are of great interest to food manufacturers as food additives of a wide spectrum of antimicrobial action with high activity at micromolar concentration. Milk protein is an easily accessible source of antimicrobial peptides. The aim of the work was to isolate an antimicrobial peptide from cow colostrum protein, followed by its classification and confirmation of biological activity in an in vitro experiment. Pepsin hydrolysate of cow colostrum and a peptide with the conditional name R(1) isolated from cow colostrum hydrolysate were used as objects of research. The antimicrobial activity of the peptide was determined by the disco-diffusion method. A polypeptide consisting of 11 amino acids with the following sequence was isolated from the pepsin hydrolysate of cow colostrum: IRHGRCVSCSR. Based on the identification of the peptide based on the Antimicrobial Peptide Database, it was found that it is 40% similar to the antimicrobial peptide AP00450, which acts ruinously on gram-positive and gram-negative bacteria. Identification by the Protein NCBI database showed the similarity of the studied peptide R(1) with an antimicrobial peptide named "14 kDaphosphohistidinephosphatase". It was found that the positive charge of the peptide is +1, the molecular weight is 7 kDa, the isoelectric point is 11.59, the hydrophilicity is + 12.51 Kcal * mol-1. The peptide belongs to the α-helical, which indicates its antimicrobial activity. The antimicrobial effect of the peptide was confirmed in an in vitro experiment.