微波辅助低共熔溶剂提取鹰嘴豆中黄酮及其抗氧化活性的研究

Extraction of Flavonoids from Chickpeas by Microwave-assisted Eutectic Solvent and Its Antioxidant Activity

以鹰嘴豆为原料,氯化胆碱基低共熔溶剂为提取剂,采用微波辅助技术提取鹰嘴豆中的黄酮类物质,探究氢键供体种类、氢键供体和受体的摩尔比、料液比、低共熔溶剂体系含水量、微波功率及微波时间对鹰嘴豆黄酮得率的影响,通过单因素实验和响应面优化试验确定了鹰嘴豆中黄酮类物质提取的最佳工艺。结果表明,以氯化胆碱为氢键受体,柠檬酸为氢键供体构建低共熔溶剂体系,二者摩尔比为1∶2,低共熔溶剂体系含水量30%(V/V),料液比1∶22 g/mL,微波功率为675 W,微波时间235 s,此时鹰嘴豆黄酮得率为2.49 mg/g,提取率可达90.55%,优于传统醇提法。体外抗氧化实验发现不同浓度的鹰嘴豆黄酮类化合物均具有一定的还原能力,以VC为阳性对照组,鹰嘴豆黄酮类化合物能显著清除DPPH·、·OH、ABTS^+·,随着浓度的增加,鹰嘴豆黄酮对DPPH·的清除率呈上升趋势,当黄酮浓度为0.05 mg/mL时,对·OH的清除率达到最大,为94.39%,当黄酮的浓度为0.15 mg/mL时,鹰嘴豆黄酮的ABTS^+·清除率最大,为73.83%。综合说明鹰嘴豆中黄酮类化合物具有良好的抗氧化活性。

Using chickpea as raw material,choline chloride eutectic solvent as extraction agent,microwave-assisted technology was used to extract flavonoids in chickpea.The effects of hydrogen bond donor species,hydrogen bond donor and acceptor molar ratio,material-liquid ratio,eutectic solvent system water content,microwave output power,and microwave time on the yield of chickpea flavonoids were explored.Experiments and response surface optimization experiments determined the optimal process parameters for the extraction of flavonoids in chickpeas:Using choline chloride as the hydrogen bond acceptor and citric acid as the hydrogen bond donor to construct a eutectic solvent system.The molar ratio was 1∶2,the water content of the eutectic solvent system was 30%(V/V),the material-liquid ratio was 1∶22 g/mL,the microwave output power was 675 W,and the microwave time was 235 s.The rate was 2.49 mg/g,and the extraction rate could reach 90.55%,which was superior to the traditional alcohol extraction method.In vitro anti-oxidation experiments found that garbanzo flavonoids at different concentrations all had a certain reducing ability.With VC as a positive control group,garbanzo flavonoids could significantly remove DPPH·,OH·and ABTS^+·.With the increasing of flavonoids concentration,the clearance rate of DPPH free radicals by chickpea flavones showed an upward trend.When the flavonoid concentration was 0.05 mg/mL,the scavenging rate for OH·reached the maximum,which was 94.39%,and when the flavonoid concentration was 0.15 mg/mL,chickpea flavonoids had the highest ABTS^+ free radical scavenging rate of 73.83%.In summary,flavonoids in chickpeas had a good antioxidant activity.