Identification and activity assay in vivo and in vitro of novel antioxidant and anti-aging peptides from C-phycocyanin of Limnospira platensis

C-phycocyanin of Limnospira platensis is a safe and nutritious protein with various activities, including antioxidant and anti-aging, indicating it is a potential protein source for preparation of antioxidant and anti-aging peptides. In this study, C-phycocyanin was purified, enzymatically hydrolyzed by seven commercial proteases , and ultrafiltered to obtain ultra-fractions with molecular weights of <3, 3–10, and >10 kDa. Their antioxidant and anti-aging activities were then evaluated in vitro and in vivo . The results demonstrated that the ultrafraction with a molecular weight of <3 kDa from C-PC hydrolysate by Papain (CPCPH-F3) exhibited high antioxidant and anti-aging activities in vitro and in Caenorhabditis elegans . Subsequently, a batch of peptides was identified from the ultrafractions using UPLC-MS/MS, and their toxicity and activities were predicted through bioinformatics analysis. Among these high antioxidant peptides, three novel antioxidant peptides (FPPWVL, FPPWF, and GW) were selected to be synthesized chemically, and their antioxidation and anti-aging activities were assessed in vitro and in Caenorhabditis elegans . Experimental results showed the three novel peptides exhibited significant antioxidant and anti-aging activities both in vitro and in vivo . These findings are beneficial for the development of bio-peptides and high-value utilization of Limnospira platensis . • Pepsin and Alcalase protease were the best proteases for the preparation of antioxidant peptides. • Ultrafiltration with <3 kDa of C-phycocyanin from L . platensis showed high antioxidant and anti-aging activities in vitro and in vivo . • Three new peptides, FPPWVL, FPPWF and GW, were demonstrated high antioxidant and anti-aging activities in vitro and in vivo .