红豆越橘中总黄酮的提取及抑菌性质研究

Optimization of Extraction Process of Total Flaonoids from Lingonberry and Evaluation of Its Antibacterial Activities

研究超声波辅助提取红豆越橘总黄酮的工艺及其抑菌作用。以超声波功率,料液比,溶剂浓度和提取时间为考察因素,以总黄酮提取率为指标,采用正交试验优化最佳提取工艺,并对其总黄酮提取液的抑菌效果进行系统研究。红豆越橘中总黄酮提取的最佳条件为,超声波功率为450 W、超声时间为25 min、乙醇浓度为50%、料液比为1∶15(g/mL),总黄酮的提取率为29.87 mg/g。抑菌试验表明,红豆越橘总黄酮提取液(pH 2.8)的浓度为40 mg/mL时,对大肠杆菌、枯草芽孢杆菌和白色葡萄球菌具有明显的抑菌作用,抑菌圈直径分别为21.17、21.67、23.91 mm;最低抑菌浓度分别为:2.5、2.5、1.25 mg/mL;红豆越橘的低pH值对总黄酮提取液的抑菌效果具有一定贡献,中和后的红豆越橘总黄酮提取液对各菌株的抑制能力显著下降。红豆越橘中总黄酮提取率可达29.87 mg/g,在酸性条件下,对枯草芽孢杆菌、白色葡萄球菌和大肠杆菌具有明显抑制作用。

To investigate ultrasonic-assisted extraction of total flavonoids from lingonberry and its antibacterial activities. Using ultrasonic power, extraction time, solvent concentration and extraction time as factors, extrac-tion yield of total flavonoids as indicator to optimize the extraction conditions of the total flavonoids from blue-berry by orthogonal experiment, the antibacterial activity of flavonoids was investigated systematically. The op-timal extraction conditions of total flavonoids of lingonberry were as follows：ultrasonic power 450 W, ultrasonic time 25 min, ethanol concentration 50 %, solid-liquid ratio 1 ： 15 （g/mL）,under above conditions, total flavonoids extraction rate was 29.87 mg/g. When the concentration（pH 2.8） of total flavonoids from lingonberry was 40 mg/mL, it had obvious antibacterial effect on Escherichia coli, Bacillus subtilis and Staphylococcus au-reus with the inhibition zone diameter of 21.17, 26.67, 23.91 mm respectively. The minimum inhibitory con-centrations （MIC） were 2.5, 2.5, 1.25 mg/mL respectively. The low pH of the total flavonoids contributed to some extend to the antibacterial activity of the flavonoids, after neutralization, the antibacterial activity de-creased significantly. The yield of flavonoids from lingonberry was 29.87 mg/g, under acidic conditions, the flavonoids had significant effect on Escherichia coli, Bacillus subtilis and Staphylococcus aureus.