Abstract

In this work, yak hide was used as the raw material to prepare collagen-derived peptides (YCDP) with high free radical scavenging activities (FRSA) via enzymolysis. The enzymolysis conditions were optimised via a single-factor experiment and response surface methodology (RSM) using the FRSA as the optimisation index. The optimal enzymolysis conditions were as follows: the optimal enzyme was alkaline protease, the enzymolysis pH was 8.7, the dosage of alkaline protease was 8000U/g, the temperature was 50°C, the time was 5 hours, the concentration of substrate was 5%. The FRSAs of hydroxyl, DPPH and superoxide anion radicals of the optimally prepared YCDP could be up to 39.63%, 71.08% and 69.93%, respectively, which were higher than those of CDP prepared from cattle hide under the same conditions. Further identification analyses showed that the components of YCDP with lower molecular weight contributed more to the FRSA of YCDP.