Cyclodextrins are widely used for various purposes and limited because of it′s low solubility.Branched cyclodextrins have attracted more and more attention because of their many advantages such as higher solubility i...Cyclodextrins are widely used for various purposes and limited because of it′s low solubility.Branched cyclodextrins have attracted more and more attention because of their many advantages such as higher solubility in water.In this study a new method for synthesizing maltosyl(α-1→6)β-cyclodextrin with a high yield was described.Mal-β-CD was synthesized through the reverse reaction of Bacillus licheniformis pullulanase and identified.The factors which affect the formation of maltosyl(α1→6)β-cyclodextrin were studied and the optimum conditions were obtained as follows: 250 U/g β-CD of enzyme amount,molar ratio of maltose to β-CD 12∶1～16∶1,a substrate mass fraction of 80%,the pH of reaction mixture 4.5,reaction temperature 70 ℃ and reaction time 60 h respectively.The product was separated by Sephadex G25 column and further purified by Bio-gel P-2 column.Maltosyl(α-1→6)β-cyclodextrin was identified by IR,ESI-MS and NMR.It was proved to be a effective method to synthesize maltosyl(α-1→6)β-cyclodextrin by using Bacillus licheniformis pullulanase.The yield of Mal-β-CD was about 56% under the optimal conditions.展开更多
10-姜酚是生姜中有益于人体健康的生物活性成分,但其水溶性较低,化学稳定性较差,限制了其在食品工业中的应用。该研究采用溶剂法联合冷冻干燥技术制备10-姜酚/麦芽糖基-β-环糊精(Mal-β-CD)的包合物,并借助紫外光谱、红外光谱、X-射线...10-姜酚是生姜中有益于人体健康的生物活性成分,但其水溶性较低,化学稳定性较差,限制了其在食品工业中的应用。该研究采用溶剂法联合冷冻干燥技术制备10-姜酚/麦芽糖基-β-环糊精(Mal-β-CD)的包合物,并借助紫外光谱、红外光谱、X-射线衍射技术、热重及差示扫描量热联用分析、分子对接模拟等技术研究包合物结构特征。结果表明,Mal-β-CD对10-姜酚具有良好的包合能力,10-姜酚与Mal-β-CD包合物的化学计量比为1∶1;10-姜酚的苯环结构和非极性侧链进入到Mal-β-CD的疏水性空腔中,二者之间形成了4个氢键,氢键键长分别为2.5魡、2.0魡、2.4魡、2.5魡,结合能为-19.32 k J/mol。10-姜酚以无定形状态存在于包合物中,其热稳定性得到了明显提高。展开更多
文摘Cyclodextrins are widely used for various purposes and limited because of it′s low solubility.Branched cyclodextrins have attracted more and more attention because of their many advantages such as higher solubility in water.In this study a new method for synthesizing maltosyl(α-1→6)β-cyclodextrin with a high yield was described.Mal-β-CD was synthesized through the reverse reaction of Bacillus licheniformis pullulanase and identified.The factors which affect the formation of maltosyl(α1→6)β-cyclodextrin were studied and the optimum conditions were obtained as follows: 250 U/g β-CD of enzyme amount,molar ratio of maltose to β-CD 12∶1～16∶1,a substrate mass fraction of 80%,the pH of reaction mixture 4.5,reaction temperature 70 ℃ and reaction time 60 h respectively.The product was separated by Sephadex G25 column and further purified by Bio-gel P-2 column.Maltosyl(α-1→6)β-cyclodextrin was identified by IR,ESI-MS and NMR.It was proved to be a effective method to synthesize maltosyl(α-1→6)β-cyclodextrin by using Bacillus licheniformis pullulanase.The yield of Mal-β-CD was about 56% under the optimal conditions.
文摘10-姜酚是生姜中有益于人体健康的生物活性成分,但其水溶性较低,化学稳定性较差,限制了其在食品工业中的应用。该研究采用溶剂法联合冷冻干燥技术制备10-姜酚/麦芽糖基-β-环糊精(Mal-β-CD)的包合物,并借助紫外光谱、红外光谱、X-射线衍射技术、热重及差示扫描量热联用分析、分子对接模拟等技术研究包合物结构特征。结果表明,Mal-β-CD对10-姜酚具有良好的包合能力,10-姜酚与Mal-β-CD包合物的化学计量比为1∶1;10-姜酚的苯环结构和非极性侧链进入到Mal-β-CD的疏水性空腔中,二者之间形成了4个氢键,氢键键长分别为2.5魡、2.0魡、2.4魡、2.5魡,结合能为-19.32 k J/mol。10-姜酚以无定形状态存在于包合物中,其热稳定性得到了明显提高。
