Study On Preparation And Antioxidant Activity Of Peptide From Camellia Seeds

It is of great academic and economic significance to explore the deep development technology of camellia seed meal protein and to prepare functional peptides for the development of new functional foods.In this paper,using camellia seed as raw material,camellia seed protein was prepared by biological enzyme-assisted extraction,then active peptides were prepared by protease hydrolysis,and then camellia seed peptides were separated by modern separation technology.the in vitro chemical model was used to evaluate the functional activity of camellia seed peptides,in order to provide research basis for the further development and utilization of tea seed resources.There are the main research contents and conclusions:1.Study on enzyme-assisted extraction of tea seed protein:taking the yield of camellia seed protein as an index,cellulase,laccase,?-amylase and pairwise compound enzymes were used to extract tea seed protein components.The results showed that the compound enzyme hydrolysis effect of a-amylase+ laccase was the best,and the compound ratio was 6:4.Through the optimization of orthogonal experiment,it is concluded that the best technology of?-amylase+ laccase compound enzymatic hydrolysis of camellia seed is 300 U/g,reaction temperature 35?,pH5.0,reaction time 60 min.Under these conditions,the yield of camellia seed protein reached(23.90±0.12)%.2.Study on the technology of enzymatic hydrolysis of tea seed peptides:taking the yield of polypeptides as an index,tea seed protein was hydrolyzed by alkaline protease,neutral protease,acid protease,papain and trypsin,and it was found that the effect of trypsin hydrolysis was the best.The results of single factor experiment and response surface experiment showed that pH and the amount of enzyme had the most significant effect on the yield of tea seed polypeptide,followed by enzymatic hydrolysis time and temperature.The optimum technological parameters for the preparation of peptides were as follows:the ratio of to liquid at 1:25(W/V),the amount of enzyme added at 1064 U/g,pH=8.5,the temperature for enzymatic hydrolysis at 63?,and the time for enzymatic hydrolysis for 4.0 h.Under these optimal conditions,the yield of polypeptide reached(74.99±0.28)%.3.Study on fractionation and antioxidant activity of tea seed peptides in vitro:tea seed protein hydrolysates were separated by ultrafiltration membranes with different interception molecular weights(<1 kDa,1 kDa-5 kDa,5 kDa-30 kDa),and three peptides were obtained.It was concluded that the antioxidant activity of T1 and T3 peptides was slightly higher than that of tea seed protein,and the antioxidant capacity of T2 peptides was significantly higher than that of camellia seed protein.At the concentration of 100mg/mL,the scavenging activities of ABTS+·free radical,DPPH·free radical and hydroxyl radical were increased by 3.32,0.25 and 0.14 times,respectively.The results showed that the peptides prepared by enzymatic hydrolysis of tea seed protein had stronger antioxidant ability.