Study On The Isolation Of Golden Pompano Visceral Acid Proteinase And Enzymatic Properties And Application

With the large increase of domestic in demand for gold pomfret and the expansion of processing, more and more waste are produced, this not only causes a huge waste of marine fisheries recourse also causes serious environmental pollution. Hainan Province which is rich in gold pomfret resources, but in the course of processing, fish head, fishtail, viscera and other waste have been abandoned and no exploitation, enzymes which contain in viscera have a very high value of development and utilization, but extraction and study on gold pomfret visceral protease rarely involved in Hainan literature even domestic and foreign literature. Therefore, utilization of high value gold pomfret viscera is needed to be resolved urgently. In this study, gold pomfret viscera was studied, visceral protease was extracted, studied the nature of the protease, analyzed the possibility of its applications in industry, and provided a basis and reference for the further study of gold pomfret, in order to improve the use value of gold pomfret.This article taked golden pomfret viscera as raw materials, through to degreasing, crushing, salting out, centrifugation, SephadexG-100 gel separation steps, obtained acid protease which can decompose gelatin, and the nature of the enzyme was further studied. The results of the study were as follows:(1) In order to study the effect of pH on the activity of gold pomfret visceral crude protease, using casein as substrate, enzyme activity was measured at pH1,2,3,4,5,6,7,8,9,10respectively. The study results showed that the enzyme activity was higher under acidic conditions, but enzyme activity was almost complete lost under alkaline condition. So, concluded that the proteases were mainly acidic protease, the test data showed that at the pH value of 4 the enzyme activity reached the highest value at present.(2) In order to further purification of gold pomfret visceral crude protease, the crude enzyme was separated by SephadexG-100 gel chromatography and obtained 3 components. Each component enzyme activity was determined by UV spectrophotometry. The results showed that the first component of the specific enzyme activity was the highest, reached to 64U/mg, compared with before the enzyme activity increased by 120%. Enzyme activity was the highest at 25℃, so it indicated that the protease was mild.(3) In order to study the effect of metal ions on enzyme activity, using casein as substrate, compounds with various metal ions added to the reaction solution were measured activity of the enzyme. The results showed that Zn2+ and Mg2+ showed activation effect, Pb2+ and Ba2+ showed inhibition effect.(4) In order to study the gold pomfret visceral proteinase’s degrading ability on gelatin, using gelatin as substrate. Using the same concentration of gold pomfret visceral proteinase and pepsin enzyme hydrolyzed gelatin respectively, the molecular weight of hydrolysate showed that pomfret visceral proteinase could decompose gelatin, and the activity was much higher than the pepsin activity.In order to study the gold pomfret visceral proteinase’s degrading ability on bovine serum albumin, using bovine serum albumin as substrate, using the same concentration of gold pomfret visceral proteinase and pepsin enzyme hydrolyzed bovine serum albumin respectively, the molecular weight of hydrolysate showed that pomfret visceral proteinase couldn’t decompose the bovine serum albumin, so the protease is unity.(5) To find out whether golden pompano visceral protease had the ability of decomposing polymer collagen, taking undenatured pigskin collagen as the substrate, gold pompano visceral protease reacted for 12 hours under the condition of pH value of 4, the results showed that golden pompano visceral protease had not the ability to break down undenatured collagen, so it determined that gold pompano visceral protease didn’t contain collagenase.Using gold pompano visceral proteases and pepsin extracted collagen from tilapia scale, extraction ration was gold pompano visceral protease less than pepsin, and we can then further purify gold pompano visceral protease for the extraction of collagen.(6) To find out gold pompano visceral protease’s applications in the extraction of astaxanthin, using the astaxanthin yield as the index, a comparative study of gold pompano visceral protease and other food industry proteases, the astaxanthin samples were measured by DPPH radical scavenging. The results showed that gold pompano visceral protease’s astaxanthin extraction rate was second to papain, above pepsin and alkaline protease, gold pompano visceral protease’s astaxanthin hydrolyzate DPPH radical scavenging rate was second to papain, above pepsin, alkaline protease.