Abstract
The extracellular aromatic peroxygenase of the agaric fungus Agrocybe aegerita catalyzed the H2O2-dependent cleavage of non-phenolic arylglycerol-β-aryl ethers (β-O-4 ethers). For instance 1-(3,4-dimethoxyphenyl)-2-(2-methoxy-phenoxy)propane-1,3-diol, a recalcitrant dimeric lignin model compound that represents the major non-phenolic substructure in lignin, was selectively O-demethylated at the para-methoxy group to give formaldehyde and 1-(4-hydroxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)propane-1,3-diol. The phenol moiety of the latter compound was then enzymatically oxidized into phenoxy radicals and a quinoid cation, which initiated the autocatalytic cleavage of the dimer and the formation of monomers such as 2-methoxy-1,4-benzoquinone and phenoxyl-substituted propionic acid. The introduction of 18O from H218O2 and H218O at different positions into the pro-ducts provided information about the routes of ether cleavage. Studies with a 14C-labeled lignin model dimer showed that more than 70% of the intermediates formed were further coupled to form polymers with molecular masses above 10 kDa. The results indicate that fungal aromatic peroxygenases may be involved in the bioconversion of methoxylated plant ingredients originating from lignin or other sources.
©2011 by Walter de Gruyter Berlin Boston
Articles in the same Issue
- Original Papers
- Lignocellulosic biorefinery: process integration of hydrolysis and fermentation (SSF process)
- Study of stilbene and resin acid content of Scots pine heartwood by electrical impedance spectroscopy (EIS)
- Radical scavenging characteristics of condensed tannins from barks of various tree species compared with quebracho wood tannin
- Two-step hydrolysis of nipa (Nypa fruticans) frond as treated by semi-flow hot-compressed water
- Effect of acetic acid addition on chemical conversion of woods as treated by semi-flow hot-compressed water
- Oxidative cleavage of non-phenolic β-O-4 lignin model dimers by an extracellular aromatic peroxygenase
- Surface chemistry of vessel elements by FE-SEM, μ-XPS and ToF-SIMS
- Application of FT-NIR-DR and FT-IR-ATR spectroscopy to estimate the chemical composition of bamboo (Neosinocalamus affinis Keng)
- Chemical modification of lignin assisted by microwave irradiation
- Acidic oxidation of kraft lignin into aromatic monomers catalyzed by transition metal salts
- Effect of Physisporinus vitreus on wood properties of Norway spruce. Part 1: Aspects of delignification and surface hardness
- Effect of Physisporinus vitreus on wood properties of Norway spruce. Part 2: Aspects of microtensile strength and chemical changes
- Mode I critical stress intensity factor of wood and medium-density fiberboard measured by compact tension test
- Effect of oxalic acid pretreatment of wood chips on manufacturing medium-density fiberboard
- Experimental investigation of stress wave propagation in standing trees
- Relationships between mechanical properties of oak timber (Quercus robur L.)
- Estimating mechanical properties and specific gravity for five-year-old Eucalyptus tereticornis having broad moisture content range by NIR spectroscopy
- Effect of morphological variability of incrusted pit membranes on efficiency of transverse compression to improve liquid uptake
- Short Notes
- Performance of biopolymer films with reinforcing cellulose-containing fillers from pine pulp and bark and birch sawdust
- Efficacy of two organic biocides with co-added antioxidants
Articles in the same Issue
- Original Papers
- Lignocellulosic biorefinery: process integration of hydrolysis and fermentation (SSF process)
- Study of stilbene and resin acid content of Scots pine heartwood by electrical impedance spectroscopy (EIS)
- Radical scavenging characteristics of condensed tannins from barks of various tree species compared with quebracho wood tannin
- Two-step hydrolysis of nipa (Nypa fruticans) frond as treated by semi-flow hot-compressed water
- Effect of acetic acid addition on chemical conversion of woods as treated by semi-flow hot-compressed water
- Oxidative cleavage of non-phenolic β-O-4 lignin model dimers by an extracellular aromatic peroxygenase
- Surface chemistry of vessel elements by FE-SEM, μ-XPS and ToF-SIMS
- Application of FT-NIR-DR and FT-IR-ATR spectroscopy to estimate the chemical composition of bamboo (Neosinocalamus affinis Keng)
- Chemical modification of lignin assisted by microwave irradiation
- Acidic oxidation of kraft lignin into aromatic monomers catalyzed by transition metal salts
- Effect of Physisporinus vitreus on wood properties of Norway spruce. Part 1: Aspects of delignification and surface hardness
- Effect of Physisporinus vitreus on wood properties of Norway spruce. Part 2: Aspects of microtensile strength and chemical changes
- Mode I critical stress intensity factor of wood and medium-density fiberboard measured by compact tension test
- Effect of oxalic acid pretreatment of wood chips on manufacturing medium-density fiberboard
- Experimental investigation of stress wave propagation in standing trees
- Relationships between mechanical properties of oak timber (Quercus robur L.)
- Estimating mechanical properties and specific gravity for five-year-old Eucalyptus tereticornis having broad moisture content range by NIR spectroscopy
- Effect of morphological variability of incrusted pit membranes on efficiency of transverse compression to improve liquid uptake
- Short Notes
- Performance of biopolymer films with reinforcing cellulose-containing fillers from pine pulp and bark and birch sawdust
- Efficacy of two organic biocides with co-added antioxidants