Antibacterial and Antioxidant Activity of Sheep Whey Protein Hydrolysates and Their Fractions

Document Type : Original Article


1 Benha University

2 Food Control& Hygiene, Faculty of Veterinary medicine, Benha University

3 Food Control&Hygiene, Faculty of Veterinary medicine,Benha University

4 Food Control&Hygiene,Faculty of veterinary medicine , Benha University

5 Department of Science and Enviroment, Roskilde University,Roskilde,Denmark


Sheep milk whey proteins are becoming more well-known for their bioactivity or health-promoting properties. Furthermore, the natural digestion of sheep whey proteins in the gastrointestinal tract generates peptides with a wide range of bioactivities, including antihypertensive, opioid, antibacterial, antioxidant, and immunomodulatory properties. In the current study, purified sheep whey protein has been applied by using size-exclusion chromatography (SEC), and it was hydrolyzed by pepsin and alcalase enzymes at concentration 2.5% (w/w) at different times 30, 60, 120 and 240 min. The highest active time hydrolysate was subsequently fractionated by SEC and monitored for its antibacterial and antioxidant activities and characterization using UHPLC-MS/MS. Alcalase enzyme showed a significantly (p˂0.05) higher degree of hydrolysis reached to 30% than pepsin enzyme. While pepsin fraction (P5) characterized by significantly (p˂0.05) higher antimicrobial activity reach to 3.18 and 2.24 log reduction against E.coli and S.aureus, respectively. For alcalase fraction (A9) exhibited significantly the highest antioxidant activity rescuing 100% of the yeast cell from Hydrogen peroxide induced oxidative stress. Proteomic analysis of the highly active fractions identified peptides from α-lactalbumin and β-Lactoglobulin from sheep whey protein with structural similarity to known antioxidant peptides and antimicrobial peptides respectively. Thus, current results supported the using food grade enzymes like alcalase and pepsin in the food industry to obtain bioactive peptides which acts as natural antimicrobial and antioxidant agent


Main Subjects

Volume 65, Issue 131 - Serial Number 13
Special Issue: Chemistry and Global Challenges (Part A)
December 2022
Pages 1511-1520
  • Receive Date: 11 May 2022
  • Revise Date: 31 May 2022
  • Accept Date: 20 June 2022