Antimicrobial Peptides Derived from Goat’s Milk Whey Proteins Obtained by Enzymatic Hydrolysis

In this study the bacterial growth inhibitory activity of peptide fragments produced from goat’s milk whey proteins by enzymatic hydrolysis using trypsin, ficin and a combination of both was investigated. Goat’s milk whey proteins were isolated and subjected to enzymatic hydrolysis and peptides were purified by ultrafiltration followed by reverse-phase high-performance liquid chromatography (RP-HPLC). Growth inhibitory activities of hydrolysates ranged from 4.67% to 87.46% for E.coli and 3.03% to 98.63% for B.cereus. Among all peptide fragments, permeate containing 3kDa peptides produced by trypsin showed maximum inhibition against Gram positive and Gram negativebac bacteria. This fraction was further purified by HPLC. Fourteen peptide fractions were collected and evaluated for their growth inhibitory activities. Two fractions showed the highest growth inhibitory activities with MIC50’s of 383±8 µg/ml and 492±10 µg/ml against E.coli and B.cereus, respectively. Taken together, the results of this study indicated that it is possible to produce novel antibacterial peptide by enzymatic hydrolysis of goat’s milk whey proteins which can potentially replace synthetic food preservatives in food industries.