Font Size: a A A

Preparation Of Tilapia Skin Collagen Peptide And Its Biological Activity

Posted on:2015-06-18Degree:MasterType:Thesis
Country:ChinaCandidate:Z Y SongFull Text:PDF
GTID:2371330512992802Subject:Engineering
Abstract/Summary:PDF Full Text Request
This paper mainly studied the optimization of hydrolysis condition of tilapia skin collagen,the preparation and purification of collagen antioxidant peptides and the pilot-scale production of collagen antioxidant and angiotensin-converting enzyme?ACE?inhibitory peptides.This paper used tilapia skin as raw material,prepared bioactivity peptides which has antioxidant functions before pilot test.The purpose was attemped to avoid wasting of biological resources,and achieve high effective utilization of tilapia by-products.The structure change of tilapia skin collagen was analysised by CD spectrum analysis under different temperatures,pure collagen from tilapia skin was hydrolyzed through crude enzymes from Pacific white shrimp viscera,DPPH·radical scavenging activity and SDS-PAGE were applied to optimize the hydrolysis condition?temperature[T],enzyme-to-substrate ratio[V:V],pH and reaction time[t]?to obtain the hydrolysate which has the highest DPPH·scavenging activity.The results indicated that the optimum conditions were:T was 40?,V:V was 5‰,pH was 8.0,and t was 2 h.Simultaneously,the degradation degree of tilapia fish skin were compared by using five kinds of commercial enzyme?compound protease,neutral protease,flavor protease,alkaline protease and papain?,the choice of alkaline protease and shrimp mixture which has better degradation degree of tilapia fish skin for enzymolysis.The results show that the optimum conditions of enzyme hydrolysis was:the enzyme mixture ratio of alkaline protease and shrimp head was 1:10,pH 8.0,the reaction temperature was 47.5?,enzymolysis time was 2h.The clearance of DPPH·could reach 85%under this condition.Collagen peptides were prepared in the optimal condition and measured their antioxidant activity in vitro.The results showed that the enzymatic hydrolysates of tilapia skin collagen had a good scavenging ability of·OH and ABTS+,IC50 were respectively 8.85 mg/mL and 2.09mg/mL;it also exihited Fe2+chelating ability,its IC50 was 0.23 mg/mL;The peptides thus prepared also effectively inhibited the activity of ACE,its IC50 was 0.61 mg/mL.Collagen peptides were separated by TSK-G2000 gel column chromatograpy,the result were analyzed by GPC software,it showed that the molecular weight of collagen peptides below 2000 Da occupied99.01%.The peptides with DPPH·scavenging activity were isolated and purified from tilapia skin collagen hydrolysates by ultrafiltration,SP Sepharose cation exchange column chromatography,Sephadex G-15 gel filtration column chromatography,C18 RP-HPLC.Ultimately,C1-1,and C1-2-2 with the scavenging ability of DPPH·were abtained,and their scavenging rate of DPPH·were respectively 10.31%and 9.42%.The pilot production of tilapia skin collagen peptide were based on the preparation of the above study,active collagen peptides with molecular weight below 1000 Da were obtained.This study established the preparation conditions of tilapia skin collagen peptides and the purification scheme of antioxidant activite peptide,and through pilot production,collagen peptide with small molecular weight were producted.It provided a basis for the deep processing of tilapia fish skin and the production of bioactive peptides.
Keywords/Search Tags:Tilapia skin collagen, Antioxidant peptides, Process optimization, Pilot scale production
PDF Full Text Request
Related items