采用硅胶柱色谱、ODS柱色谱、SephadexLH-20柱色谱、HPLC等分离方法,对金顶侧耳大米发酵乙酸乙酯提取物进行分离;通过HR-ESI-MS、1H—NMR和13C-NMR等光谱学方法对其结构进行鉴定。并检测铁氰化钾还原能力、1,1-二苯基-2-苦基苯肼(DPPH)自由基清除能力和亚铁离子螯合能力。从金顶侧耳大米发酵粗提物中分离鉴定了吲哚甲醛、苯肽等6个化合物,吲哚甲醛为首次从该菌中分离得到,活性测试表明金顶侧耳粗提取物具有一定的还原能力,其大米发酵产物有可能开发成为一种新型功能性食品。
The edible mushroom Pleurotus citrinopileatus was fermented on cooked rice by the solid-state fermentation technique. The ethyl acetate extract of the P. citrinopileatus-fermented rice showed the strong reducing ability in antioxidant bioassay. Indole-3-carboxaldehyde (1), 5, 7-dimethoxyisobenzofuran-l(3H)-one (2), 3, 5-dihydroxybenzyl acetate (3), 4-hydroxybenzaldehyde (4), 4-hydroxybenzaldehyde (5), and ergosterol (6) were isolated from the ethyl acetate extract. Their structures were elucidated on the basis of MS and NMR spectroscopic data. Their antioxidant effects of the DPPH scavenging activity, the chelating ability, and the reducing ability, were screened. The isolation of indole-3-carboxaldehyde as a secondary metabolite from edible mushroom and its structural assignment were reported for the first time. The P. citrinopileatus-fermented rice might be useful as a new functional food.