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目的：研究树发不同极性提取物的抗氧化活性及抑菌活性。方法采用DPPH自由基清除体系和β-胡萝卜素/亚油酸体系评价连续回流法得到的乙酸乙酯提取物、甲醇提取物及水提取物的抗氧化活性；通过抑菌圈试验分析不同提取物的抑菌效果。结果树发甲醇和乙酸乙酯提取物对DPPH?自由基均有较强的清除作用，其中甲醇提取物的清除率相当于同浓度人工合成抗氧化剂BHT清除率的95.90%，半抑制浓度达0.039 mg/mL；β-胡萝卜素/亚油酸体系中，甲醇提取物的抗氧化能力最强。提取物具有广谱抑菌能力，对所试14种微生物的生长都有抑制作用，对表皮葡萄球菌和肺炎克雷伯氏菌的抑制能力最强。结论树发提取物含有大量的活性成分，具有较强的生物学活性。“,”Objective This study was designed to examine antioxidant and antimicrobial activities of different polar extracts of Alectoria jubata Ach. Methods The antioxidant activities of extracts with ethyl acetate, methanol and water were detected by DPPH- free radical-scavenging method and β-carotene/linoleic acid system. The bacteriostatic effect of the three extracts was analyzed by the methods of inhibition zone. Results It’s indicated that methanol and ethyl acetate extracts had high inhibition values in DPPH- free radical-scavenging systems. Inhibition value of methanol extract to DPPH- was 95.90 % equivalent to synthetic antioxidant BHT at the same concentration, and its IC50 was 0.039 mg/mL. The extract with methanol showed the strongest antioxidant capacity in β-carotene/linoleic acid system. Meanwhile, the three extracts exhibited antibacterial ability towards the wide bacterial spectrum. They were found to strongly inhibit the growth of 14 microorganism tested, especial y Klebsiel a pneumonia and Staphylococcus epidermidis. Conclusion A large of chemical components were found in extracts of Alectoria jubata Ach, and the extracts exhibited high biologic activity.