亚麻籽木酚素酶解产物结构鉴定

Structure identification of lignin degradation enzyme hydrolysates of the lignan macromolecule

以亚麻籽为研究对象,通过60%乙醇提取亚麻籽中木酚素大分子化合物并采用木质素降解酶对其大分子进行水解,建立反相液相色谱-紫外检测法(RP-HPLC/UV)和高效液相色谱-串联质谱法(HPLC/MS/MS)两种分析方法对亚麻籽木酚素大分子酶解产物进行分离定量以及定性分析。比较了不同酶浓度下(0,0.005,0.01,0.015,0.02,0.025,0.03 u/L)亚麻籽木酚素水解产物的液相色谱图以及水解产物咖啡酸(CaAG),羟甲基戊二酸(HMGA)+木酚素二异落叶松树脂醇(SDG),SDG+阿魏酸(FeA),SDG+HMGA+对香豆酸(CouA),SDG+2HMGA+EtOH,草棉素糖苷(HDG)+HMGA的得率,结果显示最佳酶水解浓度为0.025 u/L。其中主要酶解产物CaAG和SDG+HMGA+CouA在0.025u/L酶浓度水解下得到的含量分别为7 256 mg/kg和2 574 mg/kg。通过HPLC/MS/MS分析,鉴定出酶解产物共14种,单体化合物包括CaAG、对香豆酸葡萄糖苷(CouAG)、HDG、SDG,其中SDG+HMGA(m/z=685.2[M-H+]-)和SDG(m/z=829.1[M-H+]-)检测出碎片峰。

Using the flaxseed as the research object, separation, quantification, identification and analysis of the hydrolysates had been performed by reverse-liquid-chromatography and high performance liquid chromatography tan- dem mass spectrometry after extraction the lignan macromolecule from the flaxseed by 60% ethonal and lignin degra- dation enzyme hydrolysis. According to the highest yield of CaAG, HMGA ＋ SDG, SDG ＋ FeA, SDG ＋ HMGA ＋ CouA, SDG ＋ 2HMGA ＋ EtOH, HDG ＋ HMGA of lignan macromoleeule hydrolysates at the concentration of 0u/L, 0. 005u/L, 0.01u/L, 0. 015u/L, 0.02u/L, 0. 025u/L, 0.03u/L of enzyme hydrolysis, 0. 025u/L lignin degrada- tion enzyme was selected as the optimal concentration. The main enzyme hydrolysates were CaAG and SDG ＋ HMGA ＋ CouA with the content of 7256mg/kg and 2574mg/kg. Based on the m/z-ratios and MS/MS data, four monomers including CaAG, CouAG, HDG, SDG among fourteen fractions of enzyme hydrolysates were detected, and ion frag- ment of SDG ＋ HMGA （ m/z = 685.2 [ M-H ＋ ] - ） and SDG （ m/z = 829.1 [ M-H ＋ ] - ） were detected by MS/MS.