Bioassy-directed fractionation of a culture broth of Penicillium citrinum F5 led to the isolation of a novel antioxidant 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran (1), together with gentisic acid (2), and their structures were determined on the basis of spectroscopic data. In the 1,1-diphenyl-picryl-hydrazyl (DPPH) assay system, compounds 1 and 2 showed free radical scavenging activity with IC(20) values of 10.39 and 4.26 microM, respectively.

中文翻译：

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2,3,4-三甲基-5,7-二羟基-2,3-二氢苯并呋喃，一种来自柠檬青霉F5的新型抗氧化剂。

生物素控制的柠檬青霉F5培养液的分馏导致分离出新型抗氧化剂2,3,4-三甲基-5,7-二羟基-2,3-二氢苯并呋喃（1）和龙胆酸（2） ，其结构是根据光谱数据确定的。在1,1-二苯基-吡啶基-肼基（DPPH）分析系统中，化合物1和2表现出自由基清除活性，IC（20）值分别为10.39和4.26 microM。