Total flavonoids were extracted by auxiliary ultrasonic-assisted alcohol method from raspberry dry fruit, then purified through macroporous resin XDA-6. Comparison qualities of the unpurified and purified flavonoids powder include the purity, antioxidant activity, antibacterial activity and hyphae inhibition rate. Results showed that the purity of purified flavonoids dissolved by 50 % alcohol increased by 91.10 %, antioxidant activity of purified flavonoids increased by 13.35 % at 0.25 mg/mL. The minimum inhibitory concentration (MIC) of Escherichia coli and Staphylococcus aureus droped to purified solution concentration of 2 mg/mL (the equivalent of flavonoid concentration of 0.8 mg/mL ) from unpurified solution concentration of 8 mg/mL (the equivalent of flavonoid concentration of 1.6 mg/mL ). The differences of hyphae inhibition rate of flavonoids before and after purification were higher under low concentrations than under high concentrations. The minimum difference of inhibition rate of Fusarium oxysporum f. sp. vasinfectum was 0.6%at 8 mg/mL, while the maximum difference of inhibition rate of Fusarium graminearum was 44.02%at 1 mg/mL. Therefore, the qualities of purified flavonoids were improved after purification.%用超声辅助醇法提取的树莓干果总黄酮,再经XDA-6大孔树脂纯化,比较纯化前后药粉中黄酮含量、抗氧化活性、抑菌活性以及菌丝生长抑制率的变化.结果显示:在50 %乙醇溶解条件下,纯化后黄酮含量比纯化前提高了91.10%;在纯化前后药液浓度均为0.25 mg/mL时,DPPH抗氧化活性提高最多,达到13.35%;大肠杆菌和金黄色葡萄球菌的最小抑菌浓度从纯化前的药液浓度8 mg/mL(相当于黄酮浓度1.6 mg/mL)下降为药液浓度2 mg/mL(相当于黄酮浓度0.8 mg/mL);纯化前后黄酮对小麦赤霉菌和棉花枯萎菌的菌丝抑制率表现为低浓度下提高多,高浓度下提高少的趋势,药液浓度为8 mg/mL时,对棉花枯萎菌抑菌率提高幅度最小为0.6%,而药液浓度为1 mg/mL时,对小麦赤霉菌抑菌率提高幅度最大为44.02%,说明大孔树脂纯化后黄酮的各项指标有所改善.
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