桂花子提取物体外抗氧化和抑菌活性的研究

In vitro Antioxidant and Antibacterial Activities of Osmanthus fragrans Extracts

研究桂花子黄酮和多糖清除DPPH自由基、羟自由基和ABTS~+自由基的能力,以及桂花子黄酮对大肠杆菌、金黄色葡萄球菌及枯草芽孢杆菌的抑菌活性,为桂花子提取物的保健功能应用提供理论基础。抗氧化活性试验结果表明:在试验范围内,多糖对DPPH自由基、羟自由基和ABTS~+自由基最高清除率分别为55.8%、48.5%、77.9%;黄酮对DPPH自由基、羟自由基和ABTS~+自由基最高清除率分别为90.2%、40.3%、93.4%,桂花子黄酮和多糖对DPPH自由基、ABTS~+自由基有较强的清除能力,对羟自由基的清除能力较弱。抑菌试验结果表明,桂花子黄酮对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌皆有抑制作用,对大肠杆菌和金黄色葡萄球菌的最低抑菌浓度为0.5 mg/mL,低于苯甲酸钠的最低抑菌浓度(0.625 mg/mL);对枯草芽孢杆菌的最低抑菌浓度为0.25 mg/mL;明显低于苯甲酸钠的最低抑菌浓度(1.25 mg/mL)。

The ability of Osmanthus fragrans flavones and polysaccharides to scavenge DPPH,hydroxyl,and ABTS+free radicals was studied.Furthermore,the antibacterial activity of the extracted flavones against Es-cherichia coli,Staphylococcus aureus,and Bacillus subtilis was assessed.The data provided a theoretical basis for the application of O.fragrans extracts.The highest scavenging rates of polysaccharides in the context of DPPH,hydroxyl,and ABTS+free radicals were 55.8%,48.5%,and 77.9%,respectively.Additionally,the highest scavenging rates of flavones in the context of DPPH,hydroxyl,and ABTS+free radicals were 90.2%,40.3%,and 93.4%,respectively.Therefore,O.fragrans flavones and polysaccharides potently scavenged DPPH and ABTS+free radicals,and weakly scavenged hydroxyl free radicals.Additionally,O.fragrans flavones inhibited the growth of S.aureus,B.subtilis,and E.coli.The minimum inhibitory concentration(MIC)for E.coli and Staphylococcus aureus was 0.5 mg/mL,lower than that of sodium benzoate(0.625 mg/mL).Addi-tionally,the MIC for B.subtilis was 0.25 mg/mL,significantly lower than that of sodium benzoate(1.25 mg/mL).