Study On The Enzymatic Production Of Powdered Peptides From Porcine Hemoglobin

Hemoglobin is a valuable ingredient of porcine blood. It accounts for two thirdsprotein of whole blood and more than ninety percent that of blood corpuscle. It istestified that small peptides are suitable for patients with assimilation problems, fit forallergic persons they can prevent from anaphylaxis induced by intact proteins; Theyare in favor of absorption of mineral nutrition; Some small peptides have immuneactivity, et al. Iron deficiency and anemia are the most common malnutrition in theworld, also grave in China. Heme contains Fe²⁺, the absorption of which is greaterthan ferrous salts. Heme-iron is not dependent upon dietary composition and produceslittle side effects, so it is a perfect hematinic. Peptides would maintain heme in asoluble form within wide pH range (2-12) when peptides and heme co-exist, whichcan enhance the absorption and bioavailability of heme-iron. Most of porcinehemoglobin is a waste of agricultural and food processing, the investigation on theproduct of heme-enriched peptides hydrolyzed from porcine hemoglobin can not onlyconverts the waste to the usefulness, but also prevents the harm caused by porcinehemoglobin immediately ejected into circumstance. Therefore, the investigation isgreatly ecologically meaningful and economically valuable.In order to find the best conditions of enzymatic hydrolysis, an orthogonal testwas adopted to investigate enzyme species, substrate concentration, enzymeconcentration and hydrolysis time. Total nitrogen, amino nitrogen, degree ofhydrolysis, recycle rate of protein and heme were measured. The results showed thatchoosing papain or neutral protease, 10% or 8% of substrate concentration, 4000U/gof enzyme concentration, 13h of hydrolysis time, were optimal conditions ofenzymatic hydrolysis of porcine hemoglobin.To further improve the effect of enzymatic hydrolysis of porcine hemoglobin, ahydrolysis was conducted by the combinative enzyme of papain and neutral protease.The influences of substrate concentration, proportion of enzymes, pH and temperature on degree of hydrolysis, hemochrome, total nitrogen, recycle rate of protein, aminonitrogen were investigated. The results showed that the influence of substrateconcentration was the most obvious, and 8% of substrate concentration was the bestlevel. Both pH7.0 and pH7.5 could be fit for papain and neutral protease, but pH7.5seemed to be better. The best temperature was 55℃, and the proportion of enzymeswas the least important factor, which could be determined by the practical instance.In order to explore the application of membrane technology to the clarificationand concentration of porcine hemoglobin hydrolysate, the characters of ceramicmembrane and ultrafiltration membrane, in the course of clarification andconcentration, were investigated, so did the changes of content of peptidie protein,heme, amino nitrogen. It was shown that the effect of ceramic membrane onenzymatic hydrolysate was good, and most of protein, amino nitrogen, heme wereacquired. Though a certain loss existed, it could be reduced by increasing the volumeof solution to be filtered. The retaining rate of protein by 1000D ultrafiltmtion washigh, and the multiple of concentration on heme was bigger than on amino nitrogen,showing that the application of membrane technology to clarify and condense theenzymatic hydrolysate of porcine hemoglobin was effective.To explore the application area of enzymatic hydrolysate of porcine blood, thebest conditions of decolorizing such thing with activated charcoal were investigated.With various temperature, pH, amount of activated charcoal used, time fordecolorizing, the effect of decolorizing and loss rate of protein were measured todetermine the optimum parameters. The results in the experiment showed that undersuch conditions as 3.0% of activated charcoal used, pH4, 70℃of temperature, 1.5hof time, the enzymatic hydrolysate of porcine blood were decolorized effectively, andremained high nutritional value.In order to gain better production of powder peptides, the paper explore theapplication of technology about freeze drying lyophilization.In order to determine the properties peptides, the paper explore the application oftechnology about gel- cataphoresis.