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Two fungal chloroperoxidases (CPOs), the heme enzyme from Caldariomyces fumago and the vanadium enzyme from Curvularia inaequalis, chlorinated 1-(4-ethoxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-1,3-dihydroxypropane, a dimeric model compound that represents the major nonphenolic structure in lignin. Both enzymes also cleaved this dimer to give 1-chloro-4-ethoxy-3-methoxybenzene and 1,2-dichloro-4-ethoxy-5-methoxybenzene, and they depolymerized a synthetic guaiacyl lignin. Since fungal CPOs occur in soils and the fungi that produce them are common inhabitants of plant debris, CPOs may have...

Mushroom-producing white-rot basidiomycetes can grow rapidly and produce heavy mycelial growth on treated conifer wastes with extractive-degrading fungi. This study evaluates the treatment of scaled-up conifer wood chips with Ophiostoma piliferum (Cartapip 97). Treated conifer chips were used as substrates for cultivating mushroom-producing basidiomycetes of various Pleurotus spp. This treatment reduced the extractives by 30% to 90%. These mushroom-producing lignolytic white-rot basidiomycetes can easily colonize and produce mushrooms on treated conifer wood chips.

There is now widespread acknowledgment that renewable bioresources, as a platform for raw inputs and as a source of powerful biocatalysts, have considerable potential to support sustainable economic growth, increase national energy security, strengthen rural communities, and minimize anthropogenic effects on the environment. Clearly, the transition to renewable resources from fossil fuels must meet certain replacement criteria in the economic arena. However, significant advances are required in science and technology development to help meet such criteria and to ensure sustainable enterprises.

Biopulping is the process of pretreating chips with fungus before mechanical pulping, resulting in significant energy savings and sheet strength improvements. This work presents sugar analysis, methylene blue adsorption, and titration data suggesting an increase in acid group content in wood is common with biopulping treatment. Some discussion of possible mechanisms of acid generation and fungal self-protection is presented.

Wood used in industrial settings, and in some arid parts of the United States, may be subjected to very low relative humidity (RH). Analytical models available for predicting the effect of moisture content (MC) on the properties of solid-sawn lumber imply significant strength loss at very low MC. However, these models are generally valid only for MC above about 10%. The objective of this study was to evaluate the flexural and tensile properties of standard 38-by 89-mm (nominal 2-by 4-in.) dimension lumber equilibrated at 15% RH compared with lumber at 65% RH. Testing was done on solid-sawn...

By pyrolyzing lignin model compounds 1-lV at 315°C, an investigation was carried out with some results. In the pyrolysis of lignin model compound I and 11, 0.47 mol of guaiacol, 0.57 mol of dimethoxyphenol (DMP), and 0.12 and 0.23 mol of dimethoxyaceton ophenone (DMAP) were produced respectively. In the pyrolysis of lignin model compound lll and lV, 0.26 mol of guaiacol, 0.30 mol of DMP, and 0.09 and 0.15 mol of trimethoxy acetonphenone (TMAP) were produced respectively. The results show that pyrolysis mechanism of lignin model compounds were dehydrated at first, and then guaiacol, DMP,...

Accelerated weathering of wood surfaces coated with hexadecyltrimethoxysilane (HDTMOS) in the presence of methyltrimethoxysilane (MTMOS) by the sol-gel process was investigated. The sol-gel process allowed the deposition of a covalently bound thin layer of polysiloxane networks on the wood surface that was resistant to water sorption and water leaching. The rate of weight loss resulting from surface erosion and the extent of surface color loss caused by photo- nduced discoloration were decreased for coated specimens compared to uncoated specimens.

Agave bagasse — used in tequila production — has value as bulking agent in composting trials with abattoir residuals, which are currently being landfilled.

In this study, experimental bending tests were performed on nominal 4-by 8-inch (actual 89-mm by 191-mm)lumber members to determine how a notch and holes drilled in the wide face affect edge wise bending strength. Holes were drilled at the midspan in three locations relative to the edge. The results appear to justify an allowable hole one-half the allowable knot size that is currently permitted for cedar in No. 1 Beams & Stringer grade. Furthermore, the data indicate that hole location may be as important as hole size. A1-inch (25.4-mm)hole had about the same effect on strength as a...

An extractive compound with a novel ring system was isolated from the wood of Salix alba and was given the name Salucci. The compound was primarily identified from the 1D NMR, 2D NMR and LC-MSMS data and the structure investigated through reactions and derivatizations.