摘要
用β-甘露聚糖酶水解瓜尔胶制备了半乳甘露低聚糖（Galacto-mannan-oligosaccharides,GMOS）,用时间飞行质谱（MALDI-TOF）、13CNMR表征了产物结构。以底物酶解率为指标,通过L16（43）正交实验,确定在底物质量分数为0.3%、50℃下的最佳酶解条件为：pH值7.0、酶解时间10 h、加酶量40 U.（g瓜尔胶）-1。MALDI-TOF质谱分析证明,GMOS主要由2-10个单糖组成 13CNMR分析证明,GMOS主链的D-甘露糖基C6上通过糖苷键连接有1个半乳糖残基支链。
The degradation technology of guar gum by β-mannanase hydrolysis was studied to prepare galacto-mannan-oligosaccharides（GMOS）,hydrolysis product was further characterized by MALDI-TOF and 13CNMR.Optimization of the reaction parameters was carried out using L16（43） orthogonal experiment with the enzymolysis rate of substrate as index.When the mass fraction of guar gum water solution was 0.3% at 50℃,the optimal reaction conditions were obtained as follows： β-mannanase dosage was 40 U per gram guar gum,enzymolysis time was 10 h and pH value was 7.0.MALDI-TOF Analysis showed that GMOS mainly composed of 2~10 monosaccharides.The structure of GMOS was characterized by 13CNMR.The results showed that GMOS linked a branched-chain of galactopyranosyl residue at C6 of D-mannose residue in backbone chain by glycosidic bond.
出处
《化学与生物工程》
CAS
2009年第12期37-40,共4页
Chemistry & Bioengineering
基金
广西壮族自治区科技厅应用基础研究专项资助项目(桂科基0991004号)
关键词
瓜尔胶
半乳甘露低聚糖
Β-甘露聚糖酶
表征
guar gum galacto-mannan-oligosaccharides（GMOS） β-mannanase characterization
