Studies on ligninolytic activities of ruminant microbes

反刍动物微生物木质素分解活性的研究

• 批准号: 08456134
• 负责人: KUWAHARA Masaaki
• 金额: $ 4.74万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08456134/
• 关键词: rumen; ruminant animal; lignin; LCC; リグニン分解酵素

Lignin-carbohydrate complexes (LCCs) restrict the utilization of plant cell walls by ruminants. However, degradation of LCCs into smaller fragments (i.e.oligomers) has been found to occur in the rumen. The objective of this study was to evaluate the ruminal activities of cleaving benzyl ether bonds, which are normally found in grass LCCs, by using lignin model compounds which emit fluorescence by benzyl ether bond cleavage. Two low molecula lignin models, 4-methylumbelliferone veratryl ether (VAU, dimer), and non-phenolic beta-O-4 lignin model compound incorporating 4-methylumbelliferone by benzyl ether linkage (GGU-ET trimer) were chemically synthesized. A coniferyl dehydrogenation polymer bearing fluorescent beta-O-4 benzyl ether model (F-DHP), which contained both phenolic and non-phenolic lignin substructure units, was also synthesized. They were incubated anaerobically with ruminal microbes with and without bactericidal (penicillin 2000IU/ml, streptomycin 0.2mg/ml and chlorampheni … More col 30mug/ml) and fungicidal (cycloheximide 0.5mg/ml) antibiotics, and their degradations were determined by the fluorescence yield. VAU (12muM) were degraded completely within 8hr by ruminal microbes in the presence of cycloheximide, but no significant degradation occurred in the presence of bactericidal antibiotics. GGU-ET was not degraded significantly even without any antibiotics in 48hr. F-DHP showed a partial degradation (about 20%) without any antibiotics. Both the bactericidal and fungicidal treatments showed significant degradation of F-DHP after 48hr although the incubation with sterilized ruminal fluid by a membrane filter (0.22mum pore) showed no degradation. These results indicate that ruminal microbes can cleave non-phenolic benzyl ether linkages in the dimer (VAU) especially by bacteria, but not in the trimeric beta-O-4 model (GGU-ET), and they can also degrade the synthetic lignin polymer with both phenolic and non-phenolic benzyl ether bonds (F-DHP). These results indicate that benzyl ether bonds involved in LCC macormolecules can be partially decomposed by ruminant microbes under anaerobic conditions. Less

木质素-碳水化合物复合物（LCC）限制了反刍动物对植物细胞壁的利用。然而，已发现LCC降解成较小的片段（即低聚物）发生在瘤胃中。本研究的目的是评估瘤胃的活动，裂解苄醚键，这是通常发现在草LCC，通过使用木质素模型化合物，发射荧光的苄醚键裂解。化学合成了两种低分子木质素模型化合物：4-甲基伞形酮藜芦基醚（VAU，dimer）和4-甲基伞形酮通过苄基醚键连接的非酚型β-O-4木质素模型化合物（GGU-ET trimer）。同时合成了一种含酚类和非酚类木质素结构单元的松柏基脱氢聚合物，该聚合物具有荧光β-O-4苄基醚模型（F-DHP）。将它们与瘤胃微生物在有和无杀菌剂（青霉素2000 IU/ml、链霉素0.2mg/ml和氯霉素）的情况下厌氧孵育 ...更多信息 col 30 μ g/ml）和杀真菌抗生素放线菌酮0.5mg/ml的降解率。在环己酰亚胺的存在下，VAU（12 μ M）在8小时内被瘤胃微生物完全降解，但在杀菌抗生素的存在下没有发生显着降解。在48小时内，即使没有任何抗生素，GGU-ET也没有明显降解。F-DHP在没有任何抗生素的情况下显示出部分降解（约20%）。杀菌和杀真菌处理均显示48小时后F-DHP的显著降解，尽管通过膜过滤器（0.22 μ m孔）与无菌瘤胃液孵育未显示降解。这些结果表明，瘤胃微生物可以裂解二聚体（VAU）中的非酚苄基醚键，特别是通过细菌，但不是在三聚体β-O-4模型（GGU-ET），他们也可以降解合成的木质素聚合物与酚和非酚苄基醚键（F-DHP）。这些结果表明，LCC大分子中涉及的苄基醚键在厌氧条件下可以被反刍动物微生物部分分解。少

项目成果

T.Kondo et al.: "Physico-chemical characterisctics of soluble lignin fractions released from forage grasses by ruminant digestion" Japan Agric.Res.Quarterly. 32(2) (in press). (1998)

T.Kondo 等人：“通过反刍动物消化从饲料草中释放的可溶性木质素组分的物理化学特征”日本农业研究季刊。

Y.Nakamura, T.Sawada, M.G.Sungusia, F.Kobayashi, M.Kuwahara and H.Ito: "Lignin peroxidase production by Phanerochaete chrysosporium immobilized on polyurethane foam" J.Chem.Eng.Japan. 30(1). 1-6 (1997)

Y.Nakamura、T.Sawada、M.G.Sungusia、F.Kobayashi、M.Kuwahara 和 H.Ito：“固定在聚氨酯泡沫上的黄孢原毛平革菌生产木质素过氧化物酶”J.Chem.Eng.Japan。

S.Yoshida et al.: "Effects of water-miscible organic solvents on the reaction of lignin peroxidase of Phanerochaete chrysosporium" J.Molcular Catalysis B.;Enzymatic. 2. 243-251 (1997)

S.Yoshida 等人：“与水混溶的有机溶剂对黄孢原毛平革菌木质素过氧化物酶反应的影响”J.Molular Catalysis B.；Enzymatic。

Y.Nakamura et al.: "Lignin peroxidase production by Phanerochaete chrysosporium immobilied on polyethylene foam" J.Chem.Eng.Japan. 30. 1-6 (1997)

Y.Nakamura 等人：“固定在聚乙烯泡沫上的黄孢原毛平革菌生产木质素过氧化物酶”J.Chem.Eng.Japan。

S.Yoshida,T.Watanabe,Y.Honda,M.Kuwahara: "Reaction oP Chimically Modified Lignin Peroxidase oP Phanerochaete chrysosporium in water-miscible Organic Solvents." Biosci.Biotech.Biochem.60・11. 1805-1809 (1996)

S. Yoshida、T. Watanabe、Y. Honda、M. Kuwahara：“在与水混溶的有机溶剂中化学修饰的木质素过氧化物酶的反应”，Biosci.Biotech.Biochem.60·11（1996）。