Purification and Identification of Antioxidant Peptides from Schizochytrium Limacinum Hydrolysates by Consecutive Chromatography and Electrospray Ionization-Mass Spectrometry.

Xiao Hu,Laihao Li,Xianqing Yang,Yanyan Wu,Shengjun Chen,Ruijie Li,Qiong Wu,Jiaoyan Ren

doi:10.3390/molecules24163004

Abstract

Schizochytrium limacinum residue was hydrolyzed with various proteases (papain, trypsin, Flavourzyme, Protamex, and Alcalase 2.4L) to obtain antioxidative peptides. The results showed that the S. limacinum hydrolysates (SLHs) prepared with compound proteases (Protamex and Alcalase 2.4L) had the highest antioxidant activity, which was measured using methods such as 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability (IC50 = 1.28 mg/mL), hydroxyl radical scavenging ability (IC50 = 1.66 mg/mL), and reducing power (1.42 at 5.0 mg/mL). The hydrolysates were isolated and purified by ultrafiltration, gel filtration chromatography, and reverse-phase high-performance liquid chromatography (RP-HPLC). Through analysis of electrospray ionization-mass spectrometer (ESI-MS/MS), the purified antioxidant peptide was identified as Pro-Tyr-Lys (406 Da). Finally, the identified peptide was synthesized for evaluating its antioxidant activity. The •OH scavenging ability and reducing power of Pro-Tyr-Lys were comparable to those of reduced L-glutathione (GSH). These results demonstrated that the antioxidant peptides from SLHs could potentially be used as effective antioxidants.

Highlights

Food-derived bioactive peptides, with specific amino acid sequence and biological activities, are released from proteins by protease hydrolysis
S. limacinum hydrolysates (SLHs) obtained by five proteases including papain, trypsin, Flavourzyme, Protamex, and Alcalase
Flavourzyme, Protamex, and Alcalase 2.4L were found to be more efficient than the others, and the resulting hydrolysates exhibited higher antioxidant capacity (Table 1)

Summary

Introduction

Food-derived bioactive peptides, with specific amino acid sequence and biological activities, are released from proteins by protease hydrolysis. Antioxidant peptides, as a kind of active peptide, could remove free radicals in the human body to reduce lipid, protein, and DNA oxidative degradation and oxidative damage in cells [1]. These peptides help in preventing many chronic diseases such as diabetes, cancer, and cardiovascular diseases [2]. An important natural marine biological resource, are rich in polyunsaturated fatty acids and a variety of bioactive

Methods

Results

Conclusion