Basic studies on lignin degradation with biomimetic metalloporphyrin catalysts.

仿生金属卟啉催化剂降解木质素的基础研究。

• 批准号: 61560193
• 负责人: SHIMADA Mikio
• 金额: $ 1.28万
• 依托单位: Kyoto 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: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-61560193/
• 关键词: hemin; metallo-porphyrin; lignin; C-C cleavage; enzyme model; degradation; oxygenation; one-electron oxidation; ポルフィリン; 芳香核開裂反応; 反応機構; ベラトリルアルコール

The objectives of this investigation are basically to establish the enzyme model system for understanding of lignin bioegradation mechanisms with the biomimetic metallo-porphyrin complex and also to obtain the fundamental data for development of catalytic delignification processes.The reaction mechanism for C-C bond cleavage of -1 lignin model compound was investigated and the one-electron oxidation mechanism has been established on the basis of the following results. 1) The C-C bond cleavage of the model substrate yielded the aromatic aldehyde and phenylglycol products. 2) 0-18-labeled dioxygen was proved to be incorporated at the content of 83% into the hydroxyl group of the phenylglycol product. 3) D-label of the substrate was demonstrated in the clevage product.The reaction mechanism for the aromatic ring cleavage of a non-phenolic lignin model compound vertryl alcohol was also investigated. 0-18 tracer experiments clearly indicate that the unique regiospecific oxygenations with either water or dioxygen took place during the cleavage reaction catalyzed by the hemin catalyst.These results obtained clearly showed that the iron-porphyrin complex exhibts the the same features as expressed by ligninase enzyme., which also catalyzes the one electron oxidation of a wide variety of lignin model compounds. Various factors such as solvent, pH, ligand species such as glutathione, imidazol and tyrosine, substrate or catalyst concentrations etc. were also examined.

本研究的主要目的是建立木质素与仿生金属卟啉络合物生物降解机制的酶模型系统，并为开发催化脱木质素工艺获得基础数据。研究了-1木质素模型化合物C-C键断裂的反应机理，并根据以下结果建立了单电子氧化机理。1)模型底物的C-C键裂解生成芳香醛和苯乙二醇产物。2) 0-18标记的二氧以83%的含量掺入到苯乙二醇产物的羟基中。3)基材的d标签在裂解产物中得到了验证。研究了非酚醛木质素模型化合物戊醇的芳环裂解反应机理。0-18示踪实验清楚地表明，在血红素催化剂催化的裂解反应中，与水或双氧发生了独特的区域特异性氧合。这些结果清楚地表明，铁卟啉复合物表现出与木质素酶相同的特征。，它也催化了多种木质素模型化合物的单电子氧化。考察了溶剂、pH、配体（如谷胱甘肽、咪唑和酪氨酸）、底物或催化剂浓度等因素。

项目成果

Mikio Shimada: Holzforschung. 41. 277-285 (1987)

岛田干雄：Holzforschung。

Etiene Odier: Lignin enzymic and microbial degradation. INRA Publication (Paris), 302 (1987)

Etiene Odier：木质素酶促和微生物降解。

Takefumi Hattori: Agricultural and Biological Chemistry. 52. 879-880 (1988)

服部武文：农业和生物化学。

Tsuyoshi Habe: "Biomimetic approach to lignin degradation. Effects of various factors on C-C bond cleavage of the lignin model compound." Mokuzai Gakkaishi.

Tsuyoshi Habe：“木质素降解的仿生方法。各种因素对木质素模型化合物 C-C 键断裂的影响。”

Etienne Odier: "Lignin enzymic and microbial degradation" INRA Publication(Paris), 302 (1987)

Etienne Odier：“木质素酶促和微生物降解”INRA Publication（巴黎），302（1987）