Optimisation of hydrolysis of purple sea urchin (Strongylocentrotus nudus) gonad by response surface methodology and evaluation of in vitro antioxidant activity of the hydrolysate

Dayong Zhou, Lei Qin, Beiwei Zhu, Dongmei Li, Jingfeng Yang, Xiuping Dong, Yoshiyuki Murata

Research output: Contribution to journalArticle

15 Citations (Scopus)


Background: Hydrolysates prepared from sea urchin (Strongylocentrotus nudus) gonad by enzymatic treatment showed strong 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and reducing power. Results: Hydrolysis of S. nudus gonad by the commercial protease papain was optimised for maximum degree of hydrolysis (DH) and trichloroacetic acid-soluble peptide index (TCA-SPI) using response surface methodology. Results showed that the optimal conditions were the following: temperature of 48.83 °C, pH of 6.92, enzyme-to-substrate ratio of 3143 U g -1, and substrate concentration of 83.5 g L -1. Under these conditions, a DH of 27.96 ± 0.54% and a TCA-SPI of 57.32 ± 0.63% were obtained. The hydrolysate prepared in the optimal conditions was fractionated by an ultra-filtration system and the resultant fraction below 10 kDa was found to effectively scavenge hydroxyl radical (EC 50 = 13.29 ± 0.33 mg mL -1) and hydrogen peroxide (EC 50 = 16.40 ± 0.37 mg mL -1), inhibit lipid peroxidation (EC 50 = 11.05 ± 0.62 mg mL -1), chelate Fe 2+ (EC 50 = 7.26 ± 0.44 mg mL -1), and protect mice macrophages against death induced by tert-butyl hydroperoxide. Conclusion: Hydrolysates prepared from S. nudus gonad have the potential to be applied as natural antioxidant agents.

Original languageEnglish
Pages (from-to)1694-1701
Number of pages8
JournalJournal of the Science of Food and Agriculture
Issue number8
Publication statusPublished - Jun 2012



  • Antioxidant activity
  • Degree of hydrolysis
  • Hydrolysis
  • Response surface methodology
  • Sea urchin Strongylocentrotus nudus

ASJC Scopus subject areas

  • Agronomy and Crop Science
  • Food Science
  • Nutrition and Dietetics
  • Biotechnology

Cite this