Protective effect of an antioxidative peptide purified from gastrointestinal digests of oyster, Crassostrea gigas against free radical induced DNA damage.
In this study, in vitro gastrointestinal digestion was employed to obtain potent antioxidative peptide from protein of oyster, Crassostrea gias. The protein was subjected to hydrolysate using consecutive chromatographic methods, on a Hiprep 16/10 diethylaminoethyl fast flow (DEAE FF) anion exchange column and octadecylsilane (ODS) C18 reversed phase column. Finally, the amino acid sequence of the peptide was determined. The peptide, having the amino acid sequence Leu-Lys-Gln-Glu-Leu-Glu-Asp-Leu-Leu-Glu-Lys-Gln-Glu (1.60 kDa), exhibited the higher activity against polyunsaturated fatty acid (PUFA) peroxidation than that of native antioxidant, alpha-tocopherol. The free radical scavenging assay conducted using electron spin resonance (ESR) spectroscopy, clearly exhibited that it scavenged hydroxyl radical and superoxide radical at IC50 values of 28.76 microM and 78.97 microM, respectively. Further, we investigated its antioxidant activities on cellular system, and the results showed that purified peptide significantly scavenged cellular radicals and protective effect on DNA damage caused by hydroxyl radicals generated. Furthermore (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) MTT assay showed no cytotoxicity on human embryonic lung fibroblasts cell line (MRC-5) and mouse macrophages cell (RAW264.7), respectively. These results indicate that this peptide shows potent antioxidant.
Qian
Zhong-Ji
ZJ
Department of Chemistry, Pukyong National University, Busan 608-737, Republic of Korea.
Jung
Won-Kyo
WK
Byun
Hee-Guk
HG
Kim
Se-Kwon
SK
D000818:Animals; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D004249:DNA Damage / Q000187:drug effects*; D016166:Free Radical Scavengers / Q000302:isolation & purification / Q000494:pharmacology*; D005609:Free Radicals / Q000037:antagonists & inhibitors / Q000633:toxicity*; D041981:Gastrointestinal Tract / Q000737:chemistry*; D006801:Humans; D017665:Hydroxyl Radical / Q000037:antagonists & inhibitors / Q000633:toxicity; D051379:Mice; D010125:Ostreidae / Q000737:chemistry*; D010455:Peptides / Q000302:isolation & purification / Q000494:pharmacology; D010957:Plasmids / Q000235:genetics; D020011:Protective Agents / Q000302:isolation & purification / Q000494:pharmacology*; D013481:Superoxides / Q000037:antagonists & inhibitors / Q000633:toxicity
D000975:Antioxidants; D016166:Free Radical Scavengers; D005609:Free Radicals; D010455:Peptides; D020011:Protective Agents; D013481:Superoxides; D017665:Hydroxyl Radical