3,5-O-二咖啡酰基奎宁酸的稳定性和抗氧化活性研究

Study on the Stability and Antioxidant Activity of 3,5-O-Dicaffeoylquinic Acid

目的考察影响化合物3,5-O-二咖啡酰基奎宁酸稳定性的因素并对3,5-O-二咖啡酰基奎宁酸的体外抗氧化活性进行初步研究。方法采用HPLC考察3,5-O-二咖啡酰基奎宁酸在不同溶剂、pH、温度、光照条件下的稳定性;采用UV测定3,5-O-二咖啡酰基奎宁酸的体外抗氧化活性(清除DPPH自由基)。结果溶剂的种类、pH值、温度、光照条件对3,5-O-二咖啡酰基奎宁酸稳定性具有一定影响。3,5-O-二咖啡酰基奎宁酸具有较强的体外清除DPPH自由基活性,其活性与Vc相当[3,5-O-二咖啡酰基奎宁酸和Vc的IC_(50)值分别为(372.56±1.04)μg·mL^(-1)和(294.54±1.03)μg·mL^(-1)]。结论在该化合物的分离纯化及其分析检测时,不能采用纯有机溶剂为溶剂,应在中性或酸性条件下,低温、避光操作。3,5-O-二咖啡酰基奎宁酸作为抗氧化剂在制药、食品、化妆品以及精细化工行业具有广阔的应用前景。

OBJECTIVE To investigate the factors influencing the stability of 3,5-O-dicaffeoylquinic acid and investigate the antioxidant activity of 3,5-O-dicaffeoylquinic acid in vitro. METHODS The stability of 3,5-O-dicaffeoylquinic acid in different solvents, temperatures, pH values, and illuminations were measured by HPLC. And its antioxidant activity （DPPH free radical scavenging capacity） was measured by UV. RESULTS The stability of 3,5-O-dicaffeoylquinic acid was influenced by the solvent, pH value, temperature and illumination. 3,5-O-dicaffeoylquinic acid showed strong DPPH free radical scavenging capacity [3,5-O-dicaffeoylquinic acid＇s IC50 value was （372.56±1.04）μg·mL-1, Vc＇s was （294.54±1.03）μg·mL-1]. CONCLUSION It is recommended to be stored in acidic aqueous solution under low temperature and light protection condition during the separation, purification and analytical process. 3,5-O-dicaffeoylquinic acid will have broad application prospects in pharmaceutical, foodstuff, cosmetics and fine chemicals industries as an antioxidant.