title: An identified antioxidant peptide obtained from ostrich (Struthio camelus) egg white protein hydrolysate shows wound healing properties.
abstract: BACKGROUND
  Ostrich (Struthio camelus) egg possesses a high amount of food proteins and thus plays an important role in nutrition.
  
  
  OBJECTIVE
  Ostrich egg white proteins were hydrolyzed with pepsin and pancreatin to examine its antioxidant properties and further characterized the most active peptide.
  
  
  METHODS
  Ostrich egg white protein hydrolysate (OEWPH) was fractionized using reversed phase high-pressure liquid chromatography (HPLC). The antioxidant activity of OEWPH and its HPLC fraction were investigated based on their scavenging capacity1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, 2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS), superoxide ([Formula: see text]), hydroxyl (OH(•-)) radicals, and Cu(+2) chelating. In a wound healing assay, paravertebral excision (1 cm diameter) was made on the skin and the percentage of wound closure was measured at defined intervals (0, 3, 7, and 14 d).
  
  
  RESULTS
  A potent antioxidant peptide named DG-10 with the sequence DAESLSRLLG (MW: 1060.18 ± 0.5 Da) was identified from OEWPH. The peptide DG-10 showed DPPH (IC50 = 0.0085 mg/ml), ABTS(•+) (IC50 = 0.56 mg/ml), superoxide (IC50 = 0.36 mg/ml), and hydroxyl (IC50 = 0.4 mg/ml) radical scavenger and copper chelating activity (IC50 = 0.28 mg/ml). In vitro cultured HFLF-pI 5, the cell model, also revealed that DG-10 could protect HFLF-pI 5 cells against H2O2-treated necrosis. Ointment composed of DG-10 peptide exhibited wound-healing properties on adult rats (Wistar strain). The percentage of wound closure in peptide-treated group was 98% by day 14.
  
  
  CONCLUSIONS
  Our results suggested that DG-10 is a natural agent obtained from ostrich egg possessing considerable antioxidant and wound-healing properties.
authors.affiliation: Department of Biology, Science and Research Branch, Islamic Azad University , Tehran , Iran .
authors.forename: Masoud
authors.initials: M
authors.lastname: Homayouni-Tabrizi
authors.forename: Ahmad
authors.initials: A
authors.lastname: Asoodeh
authors.forename: Mohammad-Reza
authors.initials: MR
authors.lastname: Abbaszadegan
authors.forename: Khadijeh
authors.initials: K
authors.lastname: Shahrokhabadi
authors.forename: Mahboobeh
authors.initials: M
authors.lastname: Nakhaie Moghaddam
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004527:Egg Proteins / Q000302:isolation & purification / Q000494:pharmacology*; D008297:Male; D010446:Peptide Fragments / Q000302:isolation & purification / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D020310:Struthioniformes; D013552:Swine; D014945:Wound Healing / Q000187:drug effects* / Q000502:physiology
chemical_list: D000975:Antioxidants; D004527:Egg Proteins; D010446:Peptide Fragments
keywords: Bioactive peptide; HFLF-PI 5 cell line; HPLC