不同杀青方式制备桑叶茶的体外抗氧化作用研究

On Antioxidant Effects in Vitro of Mulberry Leaf Tea by Different Fixation Way

分析不同杀青方式制备桑叶茶的体外抗氧化作用及与多酚和黄酮类质量分数的相关性,结果显示：桑叶茶具有较好的体外抗氧化能力,微波杀青效果最好.沸水及不同乙醇质量浓度提取物均有一定体外抗氧化作用,其氧自由基吸收能力、还原力和清除DPPH自由基的IC50分别为764.9±102.9-1 437.4±96.3μmol/g,5.86±0.09-9.18±0.18和139.34±11.70-225.66±8.16.经与提取物中多酚和黄酮类质量分数相关性分析显示,仅DPPH自由基清除率的IC50与多酚呈显著负相关,r=-0.791 8（p〈0.05）,表明在影响桑叶茶体外抗氧化活性中,还有其他抗氧化成分参与.

To analyze the antioxidant effect in vitro of mulberry leaf tea that is made by different fixation technology and it＇s correlation with polyphenols and flavonoids content.The results show that mulberry leaf tea has a good antioxidant effects in vitro,and among the three fixation way,microwave fixation has the best antioxidant effect.The extracts of boiling water and different concentration of ethanol have certain antioxidant effect,the oxygen radical absorbance capacity,reducing powder and the IC50 of DPPH radical scavenging capacity of different solvent extracts were 764.9±102.9-1 437.4±96.3μmol/g,5.86±0.09-9.18±0.18 and 139.34±11.70-225.66±8.16,respectively.Then,through the correlation analysis with polyphenols and flavonoids content,it has been found that only IC50 of DPPH free radical clearance is significantly negative correlation with polyphenols content（r=-0.791 8,p〈0.05）,those show that there are other antioxidants of mulberry leaf tea can influence antioxidant activity in vitro.