Studies On The Preparation And Purification Of Antioxidant-peptide And High Fischer Ratio Oligo-peptide From Hairtail

The raw material of this paper is Hairtail.By the enzymolysing Hairtail,adopting methods such as ultrafiltration,ion-exchange chromatography,gel filtration chromatography to isolate and purify enzymatic hydrolysate,antioxidant peptide products with a certain purity and activity can be obtained;prepare the High Fischer Ratio O ligo-pepfide by two step enzymatic method,carry out dearo matic and purification experiments by methods like activated carbon adsorption,gel chromatography,etc.to obtain High Fischer Ratio O ligo-pepfide,which provides theoretic and practical references for the Hairtail in the high value utilization of enzymatic hydrolysis protein.The main results are as follows:First of all,take DPPH free radicals,hydroxyl free radical scavenging capacity as indexes,optimize factors like types of optimization hydrolase,p H,enzyme dosage,enzymolysis time,temperature,substrate concentration enzyme solution,etc.,and determine that the optimum hydrolytic conditions are: the ratio of material and water: 1:5,papain(pH,7,50?;5h;enzyme 1.5%)and alkaline protease(p H,8.5,45-50?,4.5h;enzyme 3%)by double step enzyme.Secondly,by ultrafiltration,we can obtain that ultrafiltration with molecular weight less than 1 kDa component of the HTP-ions(10 mg/mL)DPPH and hydroxyl radical scavenging rate are 62.13±1.97% and 78.6±1.74%,whose antioxidant level is the highest.DEAE-52 and QFF are adopted to carry on isolation and purification,and the results indicated that the QFF comply with the best separation effect,and NaC l Tris-HC l 0.1mol/L elution.QFF-3 with p H 8.5,0.05mol/L showed the strongest comprehensive antioxidant activity.Isolating and purifying QFF-3 with G-15,strongest antioxidative components QFF-3-1 can be obtained.Carry out sequential analysis by Edman protein sequencing,determine its amino acid sequence is 10 groups of peptides,and its amino acid sequence is Gln Asn Asp Glu Arg,Lys Ser,Lys Ala,Ala Lys Gly,Ala Lys Gly,Thr Lys Ala,Ala Lys Gly,Val Lys,Met Lys,Ile Tyr Gly.Thirdly,the Hairtail is adopted as row material,and prepare High Fischer Ratio Oligo-pepfide by optimization of enzymatic hydrolysis process and two-step enzymes.The results indicated: pepsin should be selected as enzymatic hydrolysis in the first step,optimal hydrolysis process is 3% enzyme dosage,the ratio of material and water 1:5(m/V),temperature 35?,p H 2.0,3h,flavor enzyme should be selected as enzymatic hydrolysis in the second step,optimal hydrolysis process is 3% enzyme dosage,the ratio of material and water 1:5(m/V),pH7.0,50?,3h.Fourth,carry out adsorption aromatic amino acid test on enzymatic hydrolysate after powdered activated carbon and granular activated carbon,and separate and purify its product by SepHadex G-15.The result indicated that: when the powdered activated carbon is at PH6.0,1:20(m/V)activated carbon dosage,25?,3H,its removal rate is the highest;when the granular active carbon is at 1:10 solid liquid ratio,pH6.5,25 C temperature,0.6ml/min flow rate and 60 min dynamic adsorption,its removal rate is the highest.Fischer Ratio increased from 2.75 before absorption to 25.71 after absorption,and reached 30.72 when being absorbed by granular active carbon,which fitted the standard of High Fischer Ratio O ligo-pepfide.Mixture powder of Mixture powder can be obtained after cryodesiccation,and after the detection of amino acid composition,an F value which is 28.089 can be reached.