藠头抗菌成分的复合酶法提取及其抑菌性能评估

Extraction of antibacterial components from Allium chinense by compound enzymatic hydrolysis and evaluation of its antibacterial activity

目的 采用复合酶法提取藠头的天然活性成分,并研究其抑菌性能。方法 以提取到的藠头天然活性成分对大肠杆菌(Escherichia coli)的抑菌效果为评价指标,通过响应面设计获得果胶酶、纤维素酶和木聚糖酶的最适复合酶添加量,并分析和评估藠头提取物的抑菌性。结果 当果胶酶的添加量为0.1%、纤维素酶的添加量为0.1%、木聚糖酶的添加量为0.5%时,提取物对大肠杆菌的抑菌效果最好。经实验验证复合酶法提取的提取物对大肠杆菌的抑菌圈直径为(30.62±0.48) mm,与预测值(30.02 mm)相符。复合酶解法提取的藠头提取物对大肠杆菌的24h最低抑菌质量浓度为0.63%,最低杀菌质量浓度为1.25%;对金黄色葡萄球菌的24h最低抑菌质量浓度为1.25%,最低杀菌质量浓度为2.50%;对白色念珠菌的24 h最低抑菌质量浓度为0.63%,最低杀菌质量浓度为1.25%。在2倍的最低抑菌质量浓度的藠头提取物胁迫下,大肠杆菌体内的丙二醛含量增加2倍,超氧化物歧化酶、过氧化物酶和过氧化氢酶这3个抗氧化酶活力降低,膜脂质过氧化加剧,细胞开始凋亡。结论 响应面法分析所得的复合酶法提取藠头提取物的工艺参数准确可靠,藠头提取物的广谱抗菌作用应用前景广阔,可以被开发成为天然食品防腐剂。

Objective To extract the natural active components of Allium chinense by compound enzymatic hydrolysis, and study its antibacterial performance. Methods With the antibacterial effect of the extracted natural active components of Allium chinense on Escherichia coli(E. coli) as an evaluation index, the optimal compound enzyme addition of pectinase, cellulase and xylanase was obtained by response surface design, and the antibacterial activity of the extract of Allium chinense was analyzed and evaluated. Results When the addition amount of pectinase was 0.1%, the addition amount of cellulase was 0.1%, and the addition amount of xylanase was 0.5%, the antibacterial effect of the extract on E. coli was the best. The experimental verification showed that the inhibition zone diameter of the extract extracted by the composite enzyme method against E. coli was(30.62±0.48) mm, which was consistent with the prediction value of 30.02 mm. The 24 h minimum inhibitory concentration and the minimal bactericidal concentration of the extracts of Allium chinense extracted by the composite enzymolysis method against E. coli were 0.63% and 1.25%, respectively;the 24 h minimum inhibitory concentration and the minimal bactericidal concentration for Staphylococcus aureus were 1.25% and 2.50%, respectively;the 24 h minimum inhibitory concentration and the minimal bactericidal concentration for Candida albicans were 0.63% and 1.25%, respectively. The malondialdehyde content in E. coli was increased by 2 times under the stress of the Allium chinense extract with the minimum inhibitory mass concentration of 2 times, the activities of 3 antioxidant enzymes, superoxide dismutase, peroxidase and catalase,were decreased, the membrane lipid peroxidation was intensified, and the cells began to apoptosis. Conclusion The process parameters of compound enzyme hydrolysis from Allium chinense by response surface analysis are accurate and reliable, and the broad-spectrum antibacterial effect of Allium chinense extract has a broad application prospect, so it can be developed into a natural food preservative.