狐臭柴叶类黄酮的提取及其抗氧化和抑菌活性研究

Study on Extraction Process of Flavonoids from Premna Puberula Pamp.Leaves and Its Antioxidant and Antibacterial Activities

为了研究狐臭柴叶类黄酮不同极性萃取部分的抗氧化及抑菌活性,在单因素实验的基础上,通过响应面法优化得到最佳提取工艺。经石油醚、乙酸乙酯、正丁醇和水4种不同极性溶剂依次萃取狐臭柴叶类黄酮,得到石油醚萃取物、乙酸乙酯萃取物、正丁醇萃取物和水萃取物,并测定各萃取物中类黄酮含量及其抗氧化和抑菌能力。实验表明:狐臭柴叶类黄酮提取的最佳工艺条件是料液比为1∶40 g/mL,乙醇体积分数为77%,提取时间为15 min,此条件下提取率为14.93%。石油醚、乙酸乙酯、正丁醇、水进行萃取得到的4种萃取物中类黄酮含量分别占狐臭柴叶类黄酮的2.92%、6.47%、4.37%、1.17%,乙酸乙酯萃取物对DPPH自由基和ABTS^(+)自由基具有较强的清除能力,半抑制浓度(half maximal inhibitory concentration,IC_(50))值分别为0.03 mg/mL和0.07 mg/mL。石油醚、乙酸乙酯、正丁醇及水进行萃取得到的4种萃取物均有抑菌效果,乙酸乙酯萃取物抑制效果显著(P<0.05),尤其对金黄色葡萄球菌抑制效果最为显著。该结果证实了乙酸乙酯萃取物能有效富集类黄酮,且抗氧化能力及抑菌效果好,为狐臭柴叶类黄酮提取及深度开发利用提供了一定的理论参考。

In order to study the antioxidant and antibacterial activities of flavonoids extracted from different polar fractions of Premna puberula Pamp.leaves.On the basis of single factor experiment,the optimal extraction process was optimized by response surface method,and the flavonoids from leaves of Premna puberula Pamp.were extracted by petroleum ether,ethyl acetate,butyl alcohol and water in order to obtain petroleum ether extract,ethyl acetate extract,butyl alcohol extract and water extract,and the flavonoid content,antioxidant and antibacterial ability of each extract were determined.The results showed that the optimal extraction conditions were as follows:the ratio of solid to liquid was 1∶40 g/mL,the volume fraction of ethanol was 77%,the extraction time was 15 min,and the extraction rate was 14.93%.The flavonoids contents of petroleum ether,ethyl acetate,butyl alcohol and water extract accounted for 2.92%,6.47%,4.37%and 1.17%,respectively.The ethyl acetate extract had strong scavenging ability for DPPH free radicals and ABTS^(+)free radicals,with half maximal inhibitory concentration(IC_(50))values of 0.03 mg/mL and 0.07 mg/mL,respectively.Four kinds of extracts,petroleum ether,ethyl acetate,butyl alcohol and water extract,had antibacterial effect,and ethyl acetate extract had significant inhibitory effect(P<0.05),especially on Staphylococcus aureus.The results showed that ethyl acetate extract could effectively enrich flavonoids,and had good antioxidant capacity and antibacterial effect,which provided a theoretical reference for flavonoid extraction and further development and utilization of the leaves of Premna puberula Pamp.