Design-Expert软件设计优化万寿菊黄酮提取工艺及抗氧化活性、抑菌活性测定

Optimization of Extraction Process of Tagetes erecta L.Flavonoids by Design-Expert Software Design and Its Antioxidant Activity and Antibacterial Activity

以万寿菊为原料,采用负压协同超声波辅助提取万寿菊黄酮,并对其抗氧化活性进行研究。以万寿菊黄酮得率为指标,在单因素基础上,通过Design-Expert软件设计响应面试验,得到最佳工艺条件为负压0.08 MPa、超声功率402 W、超声时间30 min,在此条件下,万寿菊黄酮得率为5.18%。万寿菊黄酮的抗氧化活性结果表明,随着浓度的增加,万寿菊黄酮对DPPH自由基和羟基自由基的清除能力逐渐增强,当其浓度为250 μg/mL时,对DPPH自由基的清除率为81.73%,对羟基自由基的清除率为83.28%,表明万寿菊黄酮具有较强的抗氧化能力。万寿菊黄酮对大肠杆菌和金黄色葡萄球菌均具有一定的抑菌作用,最低抑菌浓度分别为1.0 mg/mL和1.5 mg/mL,且随着浓度的增加而不断增强。

Negative pressure combined with ultrasound was employed to extract flavonoids from Tagetes erecta L.,and then the antioxidant and antibacterial activities of the extracted flavonoids were determined.With the yield of flavonoids as the indicator,Design-Expert was used for response surface design to optimize the extraction conditions on the basis of single factor tests.The optimal extraction conditions were negative pressure of 0.08 MPa,ultrasonic power of 402 W,and extraction for 30 min,under which the the yield of flavonoids from T.erecta was 5.18%.The DPPH and hydroxyl free radical scavenging activities of the flavonoids increased in a concentration-dependent manner.The flavonoids of 250 μg/mL showed DPPH and hydroxyl free radical scavenging rates of 81.73% and 83.28%,respectively,which suggested that the flavonoids from T.erecta had strong antioxidant activity.Furthermore,the flavonoids exerted inhibitory effects on Escherichia coli and Staphylococcus aureus,with the minimum inhibitory concentrations of 1.0 mg/mL and 1.5 mg/mL,respectively.Moreover,the antibacterial effects of flavonoids enhanced with the increase in concentration.