马蹄黄总黄酮、总酚酸提取工艺优化及其抗氧化、抗菌活性研究

Optimization of extraction process for total flavonoids and total phenolic acids from Spenceria ramalana and their anti⁃oxidant,anti⁃bacterial activities

目的优化马蹄黄总黄酮、总酚酸提取工艺,并评价其抗氧化、抗菌活性。方法在单因素试验、Plackett⁃Burman设计基础上,以提取时间、提取温度、粉碎程度为影响因素,总黄酮、总酚酸提取率为评价指标,Box⁃Behnken响应面法优化提取工艺。考察提取物对DPPH自由基、羟基自由基的清除能力、总还原能力及对大肠杆菌、金黄色葡萄球菌的抑制作用。结果最佳条件为提取时间33 min,提取温度43℃,粉碎程度60目,乙醇体积分数50%,液料比40∶1,平均总黄酮、总酚酸提取率分别为34.89%、12.21%。提取物对DPPH自由基、羟自由基的IC_(50)分别为0.012、0.72 mg/mL,总还原能力较好,对各菌株表现出轻度或中度敏感,并呈量效关系。结论该方法稳定可行,可用于提取抗氧化、抗菌活性较强的马蹄黄总黄酮、总酚酸。

AIM To optimize the extraction process for total flavonoids and total phenolic acids from Spenceria ramalana Trimen and to evaluate their antioxidant,antibacterial activities.METHODS With extraction time,extraction temperature and crushing degree as influencing factors,extraction rates of total flavonoids and total phenolic acids as evaluation indices,the extraction process was optimized by Box⁃Behnken response surface method on the basis of single⁃factor test and Plackett⁃Burman design.The extracts’scavenging effects on DPPH free radical and hydroxyl free radical,total reducing capacity,and inhibitory effects on Escherichia coli and Staphylococcus aureus were investigated.RESULTS The optimal conditions were determined to be 33 min for extraction time,43℃for extraction temperature,60 mesh for crushing degree,50%for ethanol concentration,and 40∶1 for liquid⁃solid ratio,the average extraction rates of total flavonoids and total phenolic acids were 34.89%and 12.21%,respectively.The IC_(50) of extracts on DPPH free radical,hydroxyl free radical were 0.012,0.72 mg/mL,respectively,which demonstrated good reducing ability and mild or moderate sensitivities on various strains in a dose⁃effect relationship.CONCLUSION This stable and feasible method can be used for the extraction of total flavonoids and total phenolic acids from S.ramalana with strong anti⁃oxidant and anti⁃bacterial activities.