蔗渣原料中阿魏酸和对香豆酸的定量分析

Determination of Ferulic Acid and p-Coumaric Acid in Sugarcane Bagasse

利用碱水解法处理蔗渣原料,分别采用气相色谱(GC)和气相色谱-质谱联用仪(GC-MS)定量分析碱水解液中的阿魏酸和对香豆酸得率,以确定分析检测方法的优异性。同时,采用先碱水解再酸水解法提取蔗渣中的阿魏酸和对香豆酸,探究萃取溶剂和水解温度对阿魏酸和对香豆酸提取率的影响。结果表明,采用GC-MS定量分析碱水解液中阿魏酸和对香豆酸的效果优于GC。与蔗渣的碱水解法相比,先碱水解再酸水解的方法具有更高的分离效率,阿魏酸和对香豆酸得率分别从0.06%和2.00%提高到0.33%和4.04%。与三氯甲烷相比,乙酸乙酯作为萃取溶剂时,阿魏酸得率提高了23.53%,对香豆酸得率提高了6.1倍。蔗渣中阿魏酸酯和对香豆酸酯的水解效率随着水解温度的升高而提高,当温度从25℃升高到60℃,阿魏酸和对香豆酸的得率分别提高5.88%和1.78%。分析结果还表明,蔗渣原料中酯键和醚键分别占对香豆酸总键连的97.27%和2.73%,酯键和醚键分别占阿魏酸总键连的51.51%和48.49%。由此表明,蔗渣原料中对香豆酸主要以酯键与木素/碳水化合物连接,阿魏酸则以酯键和醚键与木素/碳水化合物连接。

Sugarcane bagasse was treated with alkaline hydrolysis,and ferulic acid and p-coumaric acid in one-step alkaline hydrolysate were quantitatively analyzed by gas chromatography(GC)and gas chromatography-mass spectrometry(GC-MS).Mean while,ferulic acid and p-coumaric acid from sugarcane bagasse were extracted by alkaline hydrolysis followed by acid hydrolysis,and the effects of extraction solvent and hydrolysis temperature on the extraction rate of ferulic acid and p-coumaric acid were investigated.The results showed that compared with alkali extraction,combination of alkali extraction and acid extraction hydrolyzed more p-coumarate and ferulate acids.The yields of p-coumaric acid and ferulic acid were increased from 0.06%and 2.00%to 0.33%and 4.04%,respectively.The yields were also improved with the temperature increasing.When temperature increased from 25℃to 60℃,yields of ferulic acid and p-coumaric acid were increased by 5.88%and 1.78%,respectively.Compared with using chloroform as extraction solvent,ethyl acetate could increase yields of ferulic acid and p-coumaric acid by 23.53%and 6.1 times,respectively.As a result,it was demonstrated that ester bond was the main linkage between p-coumaric acid to lignin and carbohydrate which accounted for 97.27%of total linkages in sugarcane bagasse.While,both of ester bond and ether bond were the linkages of ferulic acid to lignin or carbohydrate which respectively account for 51.51%and 48.49%of total linkages.