山银花总三萜超声辅助提取工艺优化及其抗菌抗氧化活性研究

采用响应面法优化山银花总三萜提取工艺，并研究其抑菌和抗氧化活性。以总三萜得率为评价指标，在考察单因素试验的基础上，根据响应曲面分析法优化山银花总三萜提取工艺，并分别采用倍比稀释法和清除自由基法研究山银花总三萜提取物对10种常见致病菌的抑菌作用及抗氧化活性。结果表明:山银花总三萜最佳提取工艺条件为:乙醇浓度60%、料液比1:26（g/mL）、超声温度63℃、超声时间60 min。在此工艺条件下，山银花总三萜的得率为3.37%±0.02%，与模型预测值3.36%基本一致。山银花总三萜提取物对供试菌株均有不同程度的抑制，且对大肠杆菌、金黄色葡萄球菌、铜绿假单胞菌、化脓性链球菌和肺炎链球菌抑制作用最强，最小抑菌浓度（MIC）和最小杀菌浓度（MBC）均在12.5 mg/mL以下；且对DPPH和ABTS自由基具有较好的清除作用，清除效果与总三萜浓度呈剂量-效应关系。优化后的山银花总三萜超声辅助提取工艺稳定可行，且其具有较强的广谱抗菌作用和良好的抗氧化活性。

Optimization of Ultrasonic-assisted Extraction Process for Total Triterpenoids from Lonicera confuse and Its Antibacterial and Antioxidant Activity

The ultrasonic-assisted extraction process of total triterpenoids from Lonicera confuse(TTL)was optimized using the response surface methodology(RSM),and antibacterial and antioxidant activity was analyzed. Taking total triterpenoids yield as evaluation index,on the basis of single factor experiments,the ultrasound extraction process of TTL was optimized using the method of RSM. Double dilution method was used to determine inhibitory effect of TTL against 10 species of common pathogenic bacteria,and free radical scavenging test was employed to investigate antioxidant activity. The results showed that the optimum extraction condition of TTL were as follows: ethanol concentration 60%,ratio of solid to liquid 1∶26 (g/mL),ultrasonic temperature 63 ℃,extraction time 60 min. The yield of total triterpenoids under the optimum conditions was found to 3.37%±0.02%,which was close to the model predictive value. TTL had different degrees of inhibition on the tested strains,and had the strongest inhibitory effects on Escherichia coli,Staphylococcus aureus,Pseudomonas aeruginosa,Streptococcus pyogenes and Streptococcus pneumoniae. The minimum inhibitory concentration(MIC)and the minimum bactericidal concentration(MBC)were all less than 12.5 mg/mL. Moreover,it has good scavenging effect on DPPH and ABTS free radicals,and the scavenging effect has a dose-effect relationship with the concentration of TTL.The optimized ultrasonic-assisted extraction process of TTL was stable and feasible,and the extract had strong broad-spectrum antibacterial effect and good antioxidant activity.