Study On Extraction Process And Enzymatic Modification Of Leaf Protein From Morus Alba Leaves

Mulberry leaves is the leaves of the moraceae. Modern medical system has studied the medicinal and health value of mulberry leaf.It was identified as medicine food homology and one of the plant materials used for health care products by the ministry of health. Mulberry is a kind of high-quality plant protein resources,because of relatively complete kinds amino acid, half essential amino acid and essential amino acid content. LPC is a new kind of resource which is highly valuable, since it has the source widely, rich nutrition and contains no animal cholesterol, preventing with cure, preventing aging. Taking mulberry leaves as raw material, the paper has studied the following two aspects: the extraction technology research of Mulberry leaf protein; enzymatic modification research of mulberry leaf protein.In LPC extraction technology research, This article explores the two methods which included the ultrasonic assisted extraction and cellulose enzyme assisted extraction. The experimental results show that:(1) Ultrasonic assisted extraction technology: mulberry leaf powder superfine grinding as raw materials(100 mesh), phosphate buffer(pH=8.0)as leaching agent. LPC has ultrasonic extracted of 60 min, conditioning for ultrasonic temperature 30?, ultrasonic power 100 w, the solid-liquid 1:40.Centrifugal separation to get supernatant, regulate the supernatant pH 4.5, precipitation 100 min, centrifugal separation to get precipitation, freeze-drying precipitation to get leaf protein crude extracts. The extraction yield of mulberry leaf protein crude extract was 5.7%, the mulberry leaf protein crude extract protein content was 70.53%.(2) Cellulose enzyme assisted extraction technology: mulberry leaf powder(not superfine grinding) as raw material, buffer(pH=5.0)as leaching agent. LPC has extracted of 2h, conditioning for the optimum temperature of 50?, the solid-liquid1:38, enzyme amount 4%. Adjusting the solution pH of 8, filter placed 60 min. Centrifugal separation to get supernatant, regulate the supernatant p H 4.5, precipitation 100 min, centrifugal separation to get precipitation, freeze-drying precipitation to get leaf protein crude extracts. The extraction yield of mulberry leaf protein crude extract was 6.5%, the mulberry leaf protein crude extract protein content was 85.26%. Above all, the paper choice the cellulose enzyme assisted extraction technology to extract mulberry leaf proteinIn the enzymatic modification of mulberry leaf protein test, mulberry leaf protein crude extract as raw materials.This part optimized technology which modified mulberry leaf protein with alkaline protease, papain and neutral protease by single factor and orthogonal experiment. On the basis of this process, this part compare the solubility of mulberry leaf protein which is modified by the three enzymes after two composite. Get the following conclusion: Choosing double enzyme composite modification of alkaline- neutral protease is best. The specific modification process conditions: Mulberry leaf protein concentration was 10%, first of all,mulberry leaf protein crude extracts is modified under the condition of alkaline protease for 100 min(alkaline protease modification process condition is: the enzyme amount 2%, enzymolysis temperature 60 ?, the optimum pH 9.0). After passivating enzyme, neutral protease modified 70 min(modification process conditions for: neutral protease enzyme amount 1.2%, enzymolysis temperature 60 ?, the optimum pH of 7.0). NSI can reach 94.3% after modificating mulberry leaf protein.