响应面优化超声辅助提取黄槿叶总黄酮工艺及其亚硝酸盐清除能力

旨在提高黄槿资源的利用率,探讨黄槿叶总黄酮的超声辅助提取工艺,并测定黄槿叶总黄酮对亚硝酸盐的清除能力。以黄槿叶总黄酮得率为响应值,采用超声辅助提取方法,以超声温度、超声时间、乙醇浓度和液料比为影响因素进行单因素实验,并采用响应面法对提取工艺进行优化。以VC为对照,测定黄槿叶总黄酮对亚硝酸盐的清除能力。结果表明,黄槿叶总黄酮最佳的提取工艺条件为:超声温度74℃,超声时间29 min,乙醇浓度58%,液料比29∶1 mL/g,在此条件下黄槿叶总黄酮的得率为38.15 mg/g,与预测的相对误差为0.73%,该优化工艺准确率高,可靠性强。且提取的黄槿叶总黄酮与亚硝酸盐的清除率之间存在量效关系,具有较好的亚硝盐清除能力。

Optimization of Ultrasonic Assisted Extraction of Total Flavonoids from Hibiscus tilisceus Leaves by Response Surface Methodology and Its Scavenging Ability of Nitrite

In order to improve the utilization rate of Hibiscus tiliaceus resources,the ultrasonic-assisted extraction process of total flavonoids from Hibiscus tiliaceus leaves was studied and the scavenging ability of nitrite was also investigated.Single factor experiments were performed on ultrasonic temperature,ultrasonic time,ethanol concentration and liquid-to-material ratio using extraction yield as the response value. Response surface methodology was used to optimize the extraction conditions of total flavonoids from Hibiscus tiliaceus leaves.The scavenging ability of nitrite was determined using VCas contrast.The results showed that the optimal conditions for extracting total flavonoids from Hibiscus tiliaceus leaves were as follows: Ultrasonic temperature 74 ℃,for 29 min,ethanol concentration 58%,liquid-to material ratio 29∶ 1 mL/g.Under these conditions,the extraction yield of total flavonoids from Hibiscus tiliaceus leaves was 38.15 mg/g. The relative error from the predicted value was 0.73%. The optimized process had high accuracy and reliability.There was a dose-effect relationship between the total flavonoids extracted from Hibiscus tiliaceus and the clearance rate of nitrite,which indicated that the total flavonoids had good nitrite scavenging ability.