title: Analysis of α-helix unfolding in the pine nut peptide Lys-Cys-His-Lys-Pro induced by pulsed electric field.
abstract: BACKGROUND
  A variety of analytical techniques were applied to explore the effects of pulsed electric field (PEF) on α-helix structural changes in the novel antioxidant peptide Lys-Cys-His-Lys-Pro (KCHKP, 611.76 Da).
  
  
  RESULTS
  The relative α-helix content of the KCHKP peptide was significantly altered from 100% to 89.91 ± 0.97% when the electric pulse frequency was 1800 Hz and the field intensity was 10 kV cm-1. Moreover, the 1,1-diphenyl-2-pycryl-hydrazyl (DPPH) and 2,2-azinobis diammonium salt (ABTS) radical-scavenging activities of PEF-treated KCHKP were increased from 56.31% ± 0.74% to 84.33% ± 1.23% and from 40.56% ± 0.78% to 51.33% ± 0.27%, respectively.
  
  
  CONCLUSIONS
  PEF treatment increased peptide linkage stretch vibration and altered hydrogen bonding of KCHKP. The stability of the α-helix structure was influenced by hydrogen bonds within the peptide linkage of KCHKP induced by PEF and was related to changes in antioxidant activity. © 2017 Society of Chemical Industry.
authors.affiliation: College of Food Science and Engineering, Jilin University, Changchun, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Xing
authors.affiliation: College of Food Science and Engineering, Jilin University, Changchun, PR China.
authors.forename: Sitian
authors.initials: S
authors.lastname: Zhang
authors.affiliation: College of Food Science and Engineering, Jilin University, Changchun, PR China.
authors.forename: Mingdi
authors.initials: M
authors.lastname: Zhang
authors.affiliation: College of Food Science and Engineering, Jilin University, Changchun, PR China.|School of Food Science and Technology, Dalian Polytechnic University, Engineering Research Center of Seafood of Ministry of Education, Dalian, PR China.
authors.forename: Songyi
authors.initials: S
authors.lastname: Lin
mesh_terms: D055664:Electrochemical Techniques; D009754:Nuts / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D028223:Pinus / Q000737:chemistry*; D010940:Plant Proteins / Q000737:chemistry*; D017510:Protein Folding; D058767:Protein Unfolding; D012639:Seeds / Q000737:chemistry
chemical_list: D010455:Peptides; D010940:Plant Proteins
keywords: functional mechanism; pine nut peptide; pulsed electric field; radical-scavenging activity; α-helix