Preparation And Properties Of Anti-oxidative Collagen Peptide From Fish Skin Of Cyprinus Carpio

Fish skin contains large amount of collagen.The peptides from hydrolysates of fish skin collagen can be.used in food,health care products and cosmetics.Mirror carps(Cyprinus carpio)are commonly sold in Harbin market,they are mainly consumed in fresh,and there are no deep processing products.In future,the development of deep processing of mirror carps would bring a lot of byproducts,such as fish skin.In this experiment,the skin of mirror carp was used to prepare antioxidant collagen peptides.The results of this study could provide guidance on full use of mirror carp skin.(1)Firstly,the enzyme activities of three proteases and the effects of these proteases on fish skin hydrolysis were compared.It showed that the flavourzyme was suit for preparation hydrolysate from mirror carp skin.Then single factor tests were used to determine the optimal conditions for skin hydrolysis by investigating different temperature,pH,hydrolyzing time and enzyme dosage.Results showed that the optimum conditions were followed by an enzyme dosage of 5%,with pH value of 6,0 and temperature of 50? for 2 h.The DPPH· scavenging ability of the obtained hydrolysate was 89.1%,which showed a good antioxidant activity.(2)The effects of pH,temperature,sodium chloride and sucrose on antioxidant activity of the hydrolysate were studied.Results showed it had the highest activity when pH value was 3,temperature condition was 50?.The antioxidant activity of the hydrolysate would decline with sodium chloride,while rise when sucrose added.(3)After separation by Sephadex G-15,the hydrolysate was separated into three components.Among them,component 1 had the strongest total reducing capacity,the amount of ascorbic acid equivalent was 9.283 ?g/mL;component 2 had the strongest DPPH-and O2-· scavenging capacity,reached 15.49%,10.34%respectively;and the ·OH scavenging ability of component 1 was 10.80%,which was better than the other two components.