微波辐射预处理提取花叶滇苦菜总黄酮工艺及其乙酸乙酯萃取物的抑菌活性研究

Microwave Irradiation Pretreatment on Extraction of Total Flavonoids from the Sonchus asper and Antimicrobial Activity of Its Ethyl Acetate extracts

为了探讨微波辐射预处理提取花叶滇苦菜总黄酮的工艺优化及其总黄酮提取液乙酸乙酯萃取物的抑菌活性,在单因素实验基础上,采用正交试验定总黄酮提取最佳工艺;参照CLSI标准测定乙酸乙酯萃取物对铜绿假单胞菌(ATCC9027)、铜绿假单胞菌耐药菌(PA1)、金黄色葡萄球(ATCC29213)、金黄色葡萄球菌耐药菌(SA1)、大肠杆菌(ATCC25922)等5种细菌的抑菌活性。结果表明,花叶滇苦菜地上部分总黄酮提取的最佳工艺为:微波辐射时间为120 s,微波功率为350 W,乙醇浓度为60%,水浴温度70℃,料液比1∶40 g/m L,水浴时间为60 min,此时,黄酮得率为38.328 mg/g。地下部分总黄酮提取的最佳工艺为:微波辐射时间为90 s,微波辐射功率为490 W,乙醇浓度为70%,料液比1∶30 g/m L,水浴温度为80℃,水浴时间为90 min,其黄酮得率为7.232 mg/g。乙酸乙酯萃取物具备一定抑菌活性,对金黄色葡萄球菌耐药菌的MIC分别为4(地上部分)和8 mg/m L(地下部分)。当浓度低于16 mg/m L时,对铜绿假单胞菌、铜绿假单胞菌耐药菌和大肠杆菌均无抑制作用。微波辐射预处理对花叶滇苦菜总黄酮的提取具有指导意义,总黄酮提取液乙酸乙酯萃取物对金黄色葡萄球菌具有一定的抑制作用。

In order to explore the processing of total flavonoids extracted from Sonchus asper( L.) Hill by the microwave irradiation pretreatment and the antimicrobial activity of ethyl acetate extraction of total flavonoids extracts,orthogonal experiment based on the results of one-factor experiments was used to optimize the best extraction process,and the antibacterial activity was measured with reference to the CLSI standard with 5 bacteria,such as Pseudomonas aeruginosa( ATCC9027),Pseudomonas aeruginosa( PA1),Staphylococcus aureus( ATCC29213),Staphylococcus aureus( SA1) and Escherichia coli( ATCC25922).The results showed that,the best extraction process of the total flavonoids from Sonchus asper aerial parts were as follows: Microwave irradiation time 120 s,microwave power 350 W,ethanol concentration 60%,water bath temperature70 ℃,the solid to liquid ratio 1 ∶ 40 g/m L and the water bath time 60 min. Under these conditions,the flavonoid yield was38.328 mg/g. The optimal conditions of the underground parts were as follows: Microwave irradiation time 90 s,microwave power 490 W,ethanol concentration was 70%,the solid to liquid ratio 1∶ 30 g/m L,water bath temperature was 80 ℃ and the water bath time 90 min,the flavonoid yield was 7.232 mg/g. The ethyl acetate extracts of total flavonoids extract had certain antibacterial activity. The MIC of SA1 were 4( aerial part) and 8 mg/m L( underground part),respectively. When the concentration was lower than 16 mg/m L,it had no inhibitory effect on Pseudomonas aeruginosa( ATCC9027 and PA1) and Escherichia coli( ATCC25922). Microwave assisted extraction had significant effect on the extraction of total flavonoids from Sonchus asper and the ethyl acetate extracts of total flavonoid extract had a certain inhibitory effect on Staphylococcus aureus.