title: Angiotensin-converting enzyme (ACE)-inhibitory activity of boza, a traditional fermented beverage.
abstract: BACKGROUND
  In this study the angiotensin-converting enzyme (ACE)-inhibitory activity of boza and protein fractions of boza separated according to molecular weight was determined. In addition, the effect of in vitro digestion on ACE-inhibitory activity was investigated.
  
  
  RESULTS
  The protein content, ACE-inhibitory activity and IC(50) value of boza were 1.0896 ± 0.08%, 76.76 ± 14.93% and 7.2 ± 0.28 µg protein mL(-1) respectively. The protein hydrolysate was separated into three fractions according to molecular weight (MW), i.e. MW < 5000 Da, 5000 < MW < 10 000 Da and 10 000 < MW < 20 000 Da. The lowest IC(50) value (0.268 ± 0.07 µg protein mL(-1)) was found for the fraction with 5000 < MW < 10 000 Da (P < 0.05). After in vitro digestion the ACE-inhibitory activities of stomach and intestine dialysates were almost the same (P > 0.05). The IC(50) value of stomach digest was determined as 2.06 ± 0.32 (µg protein mL(-1)). However, the IC(50) value of intestine digest could not be determined, because all dialysates with different protein concentrations displayed ACE-inhibitory activity greater than 50%.
  
  
  CONCLUSIONS
  The findings indicate that boza, protein hydrolysate, fractionated hydrolysates and dialysates obtained after in vitro digestion contain bioactive compounds with different ACE-inhibitory activities. Based on these results, boza can be considered as a good source of ACE-inhibitory peptides.
authors.affiliation: Instıtute of Natural and Applied Sciences, Ege University, İzmir, Turkey.
authors.forename: Aslı
authors.initials: A
authors.lastname: Kancabaş
authors.forename: Sibel
authors.initials: S
authors.lastname: Karakaya
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000032:analysis* / Q000494:pharmacology*; D001628:Beverages / Q000032:analysis*; D005591:Chemical Fractionation; D004063:Digestion; D005285:Fermentation; D066298:In Vitro Techniques; D012275:Oryza; D011492:Protein Hydrolysates / Q000737:chemistry / Q000302:isolation & purification; D011506:Proteins / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology; D014908:Triticum; D003313:Zea mays
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D011492:Protein Hydrolysates; D011506:Proteins