小麦麸皮中酚酸提取方法的研究

研究了酸种类、酸碱浓度、水解时间、水解顺序对小麦麸皮中束缚型酚酸释放量的影响。结果表明，酚酸在小麦麸皮中主要以束缚型形式存在，且肉桂酸类酚酸含量明显高于苯甲酸类酚酸，其中以阿魏酸的含量最高。水解方法对酚酸释放量的影响存在显著差异。采用超声波辅助有机溶剂（甲醇：丙酮：水=7：7：6）提取，酚酸释放量最高的水解条件为：先用2mol／L氢氧化钠室温水解4h，再用2mol／L盐酸于85℃下水解1h，束缚型酚酸总释放量达4719μg／g麸皮。

Effects of Hydrolysis Conditions on the Release of Phenolic Acids in Wheat Bran

Hydrolysis conditions including the kinds of acid,acid and alkaline concentration,hydrolysis time and hydrolysis sequence,were investigated to determine the effects on the release of bound phenolic acids in wheat bran.The results showed that the majority of the phenolic acids existed in a bound form in wheat bran,and cinnamic acid exhibited a much higher content than benzoic acid.The highest content of ferulic acid was observed in the cinnamic acid.Hydrolysis conditions had significant influence on the release of phenolic acids.Phenolic acids were extracted by ultrasound-assisted the mixture of methanol,acetone and water(7:7:6) extraction.The optimal conditions for releasing bound phenolic acids from wheat bran were found as follows: alkaline hydrolysis(2 mol/L NaOH,4 h,at room temperature) followed by acid hydrolysis(2 mol/L HCl,1 h at 85 ℃).Under the above-mentioned conditions,the total content of bound phenolic acids was 4 719μg/g bran.