Optimization of Extraction Process and Antibacterial Activity of Polyphenol Substances in Green Onion

提取大葱中的多酚物质，以多酚得率为指标，通过单因素和正交试验优化提取工艺。结果表明：从大葱中提取多酚的工艺优化组合为：超声功率250 W、超声时间2.5 h、乙醇浓度60%、料液比1:40 (g/mL)，在此工艺条件下，提取的多酚得率为5.938 mg/g。研究发现大葱中多酚物质对常见的细菌具有较强的抑菌作用，其中大葱多酚对三种菌株的抑制作用强弱顺序为金黄色葡萄球菌 > 大肠杆菌 > 枯草芽孢杆菌。大葱多酚的最低抑菌浓度分别为：金黄色葡萄球菌为0.50 mg/mL，大肠杆菌和枯草芽孢杆菌均为0.75 mg/mL。The polyphenol substances from green onion were extracted as the index, and the extraction process was optimized by unifactor and orthogonal test. The results show that the optimized combination of extracting polyphenols from green onion is ultrasonic power of 250 W, ultrasonic time of 2.5 h, ethanol concentration of 60%, and liquid ratio of 1:40 (g/mL). Under this process, the extracted polyphenols content is 5.938 mg/g. It was also found that the polyphenol substances in green onion have a strong antibacterial effect on the common bacteria, among which the inhibitory effect of scallion polyphenols on the three strains was Staphylococcus aureus > Escherichia coli > Bacillus subtilis. The minimconcentum inhibitory ration of S. aureus was 0.50 mg/mL for Staphylococcus aureus and 0.75 mg/mL for both E. coli and B. subtilis.