title: Effect of combined ultrasonic and alkali pretreatment on enzymatic preparation of angiotensin converting enzyme (ACE) inhibitory peptides from native collagenous materials.
abstract: The combined effect of ultrasonic and alkali pretreatment for the hydrolysis of native collagenous materials and release of ACE inhibitory peptides was investigated. The ultrasonic and alkali pretreatment of pig skin could accelerate the release of the ACE inhibitory peptides from the triple helix of collagen in early stages of hydrolysis. Furthermore, the pretreatment could also accelerate collapse of the triple helix and release more ACE inhibitory peptides during hydrolysis than collagen samples left untreated. Compared to untreated and alkali pretreated samples, the ultrasonic and alkali pretreatment could decrease the thermostability of pig skin significantly (P<0.05) because the ultrasonic and alkali pretreatment could weaken hydrogen bonds and break parts of covalent bonds in collagen, leading to damage of the triple helical structure in collagen. Therefore, the ultrasonic and alkali pretreatment could damage the triple helical structure of collagen in native collagenous materials and expose more inner sites for subsequent hydrolysis, and it could be a potential way to prepare ACE inhibitory peptides effectively from collagen-rich raw material.
authors.affiliation: College of Food Science, Southwest University, Chongqing 400716, China. Electronic address: zhy1203@163.com.
authors.forename: Yuhao
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: College of Food Science, Southwest University, Chongqing 400716, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Ma
authors.affiliation: College of Food Science and Technology, Bohai University, Food Safety Key Lab of Liaoning Province, Jinzhou 121013, China.
authors.forename: Luyun
authors.initials: L
authors.lastname: Cai
authors.affiliation: College of Food Science, Southwest University, Chongqing 400716, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.affiliation: College of Food Science, Southwest University, Chongqing 400716, China; College of Food Science and Technology, Bohai University, Food Safety Key Lab of Liaoning Province, Jinzhou 121013, China. Electronic address: lijr6491@163.com.
authors.forename: Jianrong
authors.initials: J
authors.lastname: Li
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000737:chemistry* / Q000494:pharmacology*; D000818:Animals; D003094:Collagen / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008970:Molecular Weight; D010446:Peptide Fragments / Q000737:chemistry* / Q000494:pharmacology*; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism*; D013552:Swine; D013816:Thermodynamics; D000069453:Ultrasonic Waves
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D010446:Peptide Fragments; D003094:Collagen; D007703:Peptidyl-Dipeptidase A
keywords: ACE-inhibitory peptides; Native collagenous materials; Pretreatment; Ultrasonic and alkali