Effect of Hydrophobic Resion of Hemicelluloses on Dehydrogenative Polymerization of Monolignols

半纤维素疏水化对木质素单体脱氢聚合的影响

• 批准号: 02660174
• 负责人: TANAHASHI Mitsuhiko
• 金额: $ 1.41万
• 依托单位: Gifu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1991
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02660174/
• 关键词: Dehydrogenative polymerization; Hemicellulose; Hydrophobic resions; Lignin; beta-Aryl ether; Resinol; Sinapyl alcohol; Coniferyl alcohol; ペルオキシダ-ゼ; βーエ-テル結合; シリンガレジノ-ル

Dehydrogenation polymer (DHP) is using as a model of lignins to research the chemical structure and the blosyntheses of native lignins. However, some chemical and physical properties of DHPs, which are prepared by any methods, Zulaufverpharen and Zutropverfahren deveroped by Froudenberg differs from the native lignin. Especially, the reaction products of the dehydrogenative polymerization of sinapyl alcohol differs from the reaction in the living tree compared with the coniferyl alcohol-DHP. In a plant cell wall, lignin was deposited in the matrix of polysaccharides through the lignification process. To demonstrate the effect of hemicelluloses on dehydrogenative polymerization, sinapyl alcohol was dehydrogenated with horseradish peroxidase/H202 in the presence of pectin by Zulaufverfahren method. Main reaction products, which were syringylglycerol-bsinapyl alcohol ether, d, l-siringaresinol and an unknown compound, were isolated by PTLC after acetylation and analyzed by NMR and MS spec … More trometry. As a result, the unknown compound identified 1, 5-di(3, 5-dimethoxy-4-hydroxyphenyl)-1-hydroxy-2-hydroxymethyl-1-pentene(b-r type). This substructure would be present in native lignin, and generated by ionic reaction through ihe extended quinonemethide-intermediate. Effect of reaction media on dehydrogenation polymerization of sinapyl alcohol were examined. Sinapyl alcohol was dehydrogenated with FeCl3 and peroxidase / H202 under various pH and polarity by Zulaufverfahren method. From these results, when sinapyl alcohol was dehydrogenated with FeCl3, the ratio of b-0-4 type dimeric compound was increased with increasing of dioxane content and acidity. This phenomenon could be explained that the E-effect of methoxyl group of sinapyl alcohol was suppressent in low polar and low pH solbents. However, with peroxidase/H202 sinapyl alcohol gave syringaresinol mainly. Hence, it could be considered that there was difference between the two reaction mechanisms, and it might be suggested that the radical carrier as a mediater oxidated lignols in the plant cell wall through the lignification. Less

脱氢聚合物（DHP）作为木质素的模型化合物，研究天然木质素的化学结构和生物合成。然而，由Froudenberg开发的Zulaufverpharen和Zutropverfahren等各种方法制备的DHP的某些化学和物理性质与天然木质素不同。特别是芥子醇的缩聚反应产物与松柏醇-DHP的缩聚反应产物相比，与活树中的缩聚反应产物不同。在植物细胞壁中，木质素通过木质化过程沉积在多糖基质中。为了证明半纤维素对分解聚合的影响，通过Zulaufverfahren方法在果胶存在下用辣根过氧化物酶/H2 O2脱氢芥子醇。乙酰化后的主要反应产物经薄层层析分离得到丁香甘油-芥子醇醚、d，l-丁香树脂酚和一个未知化合物，并经核磁共振和质谱分析 ...更多信息 测重法结果，未知化合物鉴定为1，5-二（3，5-二甲氧基-4-羟基苯基）-1-羟基-2-羟甲基-1-戊烯（b-r型）。这种亚结构存在于天然木质素中，并通过延伸的醌甲基中间体通过离子反应产生。考察了反应介质对芥子醇脱氢聚合的影响。采用Zulaufverfahren法，在不同pH和极性条件下，用FeCl_3和过氧化物酶/H_2 O_2对芥子醇进行脱氢。结果表明，芥子醇经FeCl 3脱氢后，随着二氧六环含量和酸度的增加，B-0-4型二聚体的比例增加。这一现象可以解释为芥子醇甲氧基的E-效应在低极性和低pH溶剂中受到抑制。然而，与过氧化物酶/H202芥子醇主要得到了双辛树脂酚。因此，可以认为这两种反应机理存在差异，可能是自由基载体作为介体通过木质化作用氧化了植物细胞壁中的木质素。少

项目成果

吉田 晋一,棚橋 光彦,篠田 善彦: "Effect of Hemicelluloses on Dehydrogenative Polymelization of Sinapyl Alcohol" 木材学会誌.

Shinichi Yoshida、Mitsuhiko Tanahashi、Yoshihiko Shinoda：“半纤维素对芥子醇脱氢聚合的影响”日本木材学会杂志。