title: Purification and identification of a ACE inhibitory peptide from oyster proteins hydrolysate and the antihypertensive effect of hydrolysate in spontaneously hypertensive rats.
abstract: Oyster (Crassostrea talienwhanensis Crosse) proteins were produced from fresh oyster and subsequently digested with pepsin. The separations were performed with a Sephadex LH-20 gel filtration chromatography and a RP-HPLC. A purified peptide with sequence Val-Val-Tyr-Pro-Trp-Thr-Gln-Arg-Phe (VVYPWTQRF) was firstly isolated and characterized from oyster protein hydrolysate and its ACE inhibitory activity was determined with IC50 value of 66μmol/L in vitro. Stability study for ACE inhibitory activity showed that the isolated nonapeptide had the good heat and pH stability and strong enzyme-resistant properties against gastrointestinal proteases. Kinetic experiments demonstrated that inhibitory kinetic mechanism of this peptide was non-competitive and its Km and Ki values were calculated. The yield of this peptide from oyster proteins was 8.5%. Furthermore, the oyster protein hydrolysate (fraction II), prepared by pepsin treatment firstly exhibited antihypertensive activity when it was orally administered to spontaneously hypertensive rat (SHR) at a dose of 20mg/kg. These results demonstrated that the hydrolysate from oyster proteins prepared by pepsin treatment could serve as a source of peptides with antihypertensive activity.
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 1805 Group, 457 Zhongshan Road, Dalian 116023, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China. Electronic address: wangjiapei1979@gmail.com.
authors.forename: Jiapei
authors.initials: J
authors.lastname: Wang
authors.affiliation: Dalian Fisheries University, Dalian 116023, China.
authors.forename: Jianen
authors.initials: J
authors.lastname: Hu
authors.affiliation: School of Art and Design, Dalian Institute of Light Industry, Dalian 116034, China.
authors.forename: Jinzhe
authors.initials: J
authors.lastname: Cui
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 1805 Group, 457 Zhongshan Road, Dalian 116023, China.
authors.forename: Xuefang
authors.initials: X
authors.lastname: Bai
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 1805 Group, 457 Zhongshan Road, Dalian 116023, China. Electronic address: articles1805@gmail.com.
authors.forename: Yuguang
authors.initials: Y
authors.lastname: Du
authors.affiliation: College of Agriculture, Ibaraki University, Ibaraki 300-0393, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Miyaguchi
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 1805 Group, 457 Zhongshan Road, Dalian 116023, China.
authors.forename: Bingcheng
authors.initials: B
authors.lastname: Lin
keywords: ACE inhibitory peptides; Hypertension; Oyster protein hydrolysate; Purification and identification; Spontaneously hypertensive rat