青刺果抗菌肽组分的分离及其稳定性分析

旨在高值化利用青刺果榨油后副产物青刺果粕中的蛋白质，以青刺果粕为原料，提取青刺果蛋白并制备蛋白酶解物，采用活菌吸附法联合反相高效液相色谱（RP-HPLC）从蛋白酶解物中筛选出抗菌肽组分，评价其抑菌活性，并对抑菌活性最好的组分进行稳定性分析。结果表明：筛选出的3个抗菌肽组分（F1、F2和F3）中，F2组分抑菌活性最好，当其质量浓度为10 mg/mL时对金黄色葡萄球菌和大肠杆菌的抑菌活性分别达到45.5%和39.1%；抗菌肽组分F2抑菌活性随温度升高和盐溶液浓度增加均降低，最适pH为6.0，在酸性环境中极不稳定，对酸性蛋白酶、碱性蛋白酶、胃蛋白酶和胰蛋白酶的耐受性均较差，对中性蛋白酶耐受性较好。综上，青刺果粕中的蛋白酶解物具有抑菌活性，具有开发青刺果抗菌肽的潜力。

Isolation and stability of antimicrobial peptide fraction from Prinsepia utilis Royle

In order to make high value use of the proteins in the by-products of Prinsepia utilis Royle oil extraction, Prinsepia utilis Royle proteins were extracted from the meal of Prinsepia utilis Royle and then hydrolyzed to prepare hydrolysates. The antimicrobial peptide fractions were screened from the hydrolysates by using live bacterial adsorption combined with reversed-phase high-performance liquid chromatography (RP-HPLC), their antibacterial activities were evaluated, and the stability of the fraction with the best antibacterial activity was analyzed. The results showed that among the three antimicrobial peptide fractions (F1, F2 and F3) screened, the F2 fraction had the best antibacterial activity, and its antibacterial activities against Staphylococcus aureus and Escherichia coli reached 45.5% and 39.1%, respectively, at a mass concentration of 10 mg/mL. The antibacterial activity of the antimicrobial peptide fraction F2 was reduced with the increase of temperature and salt solution concentration, and its optimal pH was 6.0, and it was extremely unstable in an acidic environment. The antimicrobial peptide fraction F2 was poorly tolerated by acid protease, alkaline protease, pepsin and trypsin, and better tolerated by neutral protease. In conclusion, the enzymatic hydrolysates of protein in the meal of Prinsepia utilis Royle have antibacterial activity, and has potential for the development of antimicrobial peptides from Prinsepia utilis Royle.