title: Effect of whey protein hydrolysates with different molecular weight on fatigue induced by swimming exercise in mice.
abstract: BACKGROUND
  In order to improve the antioxidant and anti-fatigue capacities of whey protein for wider utilization, it was hydrolyzed by chymotrypsin (EC 3.4.21.1) to produce whey protein hydrolysate (WPH). Fractions of WPH with different molecular weight (MW) were separated by ultrafiltration. Kunming mice in various treatment groups were orally administered (1.5 g kg(-1) body weight) whey protein isolate (WPI), WPH or WPHs with different MW (<5, 5-10, 10-30 or >30 kDa) for 6 weeks to explore whether different MW fractions of WPH affected mice fatigue.
  
  
  RESULTS
  Compared with the control group (orally administered 9 g kg(-1) saline) or the WPI group, low-MW (<10 kDa) WPH groups showed prolonged swimming time (P < 0.05) and had higher concentrations (P < 0.05) of glucose, non-esterfied fatty acid, liver glycogen, superoxide dismutase and glutathione peroxidase and lower concentration of lactate. Low-MW (<10 kDa) WPHs had higher hydroxyl- and α,α-diphenyl-β-picrylhydrazyl-scavenging abilities and ferrous-chelating capacity than WPI.
  
  
  CONCLUSIONS
  The results proved that low-MW (<10 kDa) WPHs with higher anti-fatigue capacity showed higher free radical-scavenging and ferrous-chelating activities.
authors: Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, 300457, Tianjin, China; College of Bioscience and Bioengineering, Hebei University of Economics and Business, Shi Jiazhuang, China.
authors: Jing
authors: J
authors: Liu
authors: Xinxia
authors: X
authors: Wang
authors: Zheng
authors: Z
authors: Zhao
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000032:analysis; D001786:Blood Glucose / Q000032:analysis; D002918:Chymotrypsin / Q000378:metabolism; D005221:Fatigue / Q000378:metabolism / Q000517:prevention & control*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005296:Ferrous Compounds; D016166:Free Radical Scavengers; D006003:Glycogen / Q000032:analysis; D006868:Hydrolysis; D007502:Iron Chelating Agents; D019344:Lactic Acid / Q000097:blood; D008099:Liver / Q000737:chemistry; D008297:Male; D051379:Mice; D008894:Milk Proteins / Q000008:administration & dosage* / Q000737:chemistry / Q000378:metabolism; D008970:Molecular Weight; D018482:Muscle, Skeletal / Q000737:chemistry / Q000187:drug effects; D005082:Physical Exertion / Q000502:physiology*; D011492:Protein Hydrolysates / Q000008:administration & dosage* / Q000737:chemistry; D013550:Swimming; D000067816:Whey Proteins
chemical_list: D000975:Antioxidants; D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D005296:Ferrous Compounds; D016166:Free Radical Scavengers; D007502:Iron Chelating Agents; D008894:Milk Proteins; D011492:Protein Hydrolysates; D000067816:Whey Proteins; D019344:Lactic Acid; D006003:Glycogen; D002918:Chymotrypsin
keywords: antifatigue; antioxidant capacity; molecular weight distribution; whey protein hydrolysates