The Preparation Of Hydrolyzed Collagen From Chicken Bone By Enzyme And The Research Of Antioxidant Activity

Chicken bone contains abundant nutrients and a large amount of collagen exists in it.In this study,the collagen was extract from chicken bone and hydrolyzed to prepare hydrolyzed collagen.In addition,the antioxidant activity in vitro and in vivo was researched.Firstly,the optimal extraction conditions were confirmed.Results shown that decalcification rate reached 96.38%when 4%hydrochloric acid was used for 10h,the content of collagen was slightly improved when immersed in 0.1%Ca(OH)₂ for 24h by eliminating other protein,and boiled for 5h.By this way,the collagen from chicken bone with ash of 2.27%,protein of 88.75%and collagen of 86.02%were obtained.Secondly,Alcalase and Flavourzyme were selected to prepare the hydrolyzed collagen.In view of the DH,the optimal hydrolysis conditions of Alcalase were 65℃,pH8.0 and 3h. Taking the scavenging rate of·OH into account,the optimal hydrolysis conditions of Flavourzyme were 55℃,pH5.5,50000U/g and 4h.By analyzing,the molecular-weight of hydrolyzed collagen focused on four narrow ranges.They are more than 11000Da,1010-600Da,600-300Da and 300-190 Da.Thirdly,account for the distribution of molecular weight,hydrolyzed collagen were desalted and classified by ultrafiltration and nano-filtration respectively.By this way,CBOP-C with high antioxidant activity was got.The range of molecular-weight is 2000-500Da (61.387%) and 400-195Da(38.613%) by GPC,and the average molecular-weight is 841.16Da. Results shown that CBOP-C is compound peptide with high equipotential solubility,Thermal Stability,oil retention and poor water retention,water absorbency,emulsification,spumescence.At last,the antioxidant activity of CBOP-C in vitro and in vivo was studied.In vitro,the CBOP-C can reduce the POV of lard and colza oil,scavenge the·OH,DPPH·,O₂^-, deoxidize the iron.In vivo,D-gal-induced-rats were used to evaluate the antioxidant activity with low-dose,high-dose CBOP-C compared with V_E.In a word,CBOP-C can improved the activity of SOD,GSH-Px and CAT in serum,liver tissue and brain tissue(P＜0.05),at the same time,reduced MDA content(P＜0.05).