In vitro oxidative and enzymatic degradation of modified wood

Abstract

Fungal cellulases have been shown to be less efficient in modified wood than in untreated wood (Lekounogou et al. 2008; Venås 2008). However, Verma and Mai (2010) showed that cellulase efficacy is partly restored in 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) treated wood by pre-treatment with Fenton's reagent, simulating the oxidative degradation phase in initial brown rot decay. In this study, we examined whether Fenton derived hydroxyl radicals (·OH) and cellulases are able to cleave polysaccharides in furfurylated and acetylated wood and to what extent enzyme efficacy is increased by oxidative pre-treatment of these materials. The results show that fungal cellulases were able to degrade acetylated wood and that the cellulase efficacy was increased by oxidative pre-treatment by 20%, which is half of the increase in untreated wood. Furthermore, the results indicate that poly(furfuryl alcohol) is degraded by Fenton derived ·OH. This indicates a possible route for the eventual degradation of modified wood.

Keywords

Acetylated wood Chelator mediated Fenton (CMF) degradation Fenton's reagent Furfurylated wood Mode of action

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References

Arantes

, Jellison

and Goodell

. 2012. Peculiarities of brown-rot fungi and biochemical Fenton reaction with regard to their potential as a model for bioprocessing biomass. Appl. Microbiol. Biotechnol. 94: 323–338.

Baldrian

and Valaskova

. 2008. Degradation of cellulose by basidiomycetous fungi. FEMS Microbiol. Rev. 32 (3): 501–521.

Boonstra

and Tjeerdsma

. 2006. Chemical analysis of heat treated softwoods. Holz Roh Werkst. 64 (3): 204–211.

EN 84 . 1996. Wood preservatives. Accelerated ageing of treated wood prior to biological testing. Leaching procedure. European Committee for Standardization (CEN), Brussels, Belgium. Page 7.

Fenton

HJH

. 1894. Oxidation of tartaric acid in the presence of iron. J. Chem. Soc. Trans. 65: 899–911.

Goodell

, Jellison

, Liu

, Daniel

, Paszcynski

, Fekete

, Krishnamurthy

, Jun

and Xu

. 1997. Low molecular weight chelators and phenolic compounds isolated from wood decay fungi and their role in the fungal biodegradation of wood. J. Biotechnol. 53: 133–162.

Goodell

, Daniel

, Jellison

and Qian

. 2006. Iron-reducing capacity of low-molecular-weight compounds produced in wood by fungi. Holzforschung 60: 630–636.

Hill

. 2006. Wood modification: chemical, thermal and other processes. Chichester: John Wiley and Sons.

Hill

CAS

, Forster

, Farahani

MRM

, Hale

MDC

, Ormondroyd

and Williams

. 2005. An investigation of cell wall micropore blocking as a possible mechanism for the decay resistance of anhydride modified wood. Int. Biodeterior. Biodegrad. 55 (1): 69–76.

10.

Lande

, Westin

and Schneider

. 2004. Properties of furfurylated wood. Scandinavian Journal of Forest Research 19 (5): 22–30.

11.

Lande

, Eikenes

and Westin

. 2004. Chemistry and ecotoxicology of furfurylated wood. Scand. J. For. Res. 19: 14–21.

12.

Larsson-Brelid

. 1998. Acetylation of solid wood. PhD thesis. Chalmers University of Technology, Gothenburg, Sweden.

13.

Lekounougou

, Pétrissans

, Jacquot

, Gelhaye

and Gérardin

. 2008. Effect of heat treatment on extracellular enzymatic activities involved in beech wood degradation by Trametes versicolor. Wood Sci. Technol. 43 (3–4): 331–341.

14.

Miller

. 1959. Use of dinitrosalicylic acid reagent for determination of reducing sugar. Anal. Chem. 31: 426–428.

15.

Nordstierna

, Lande

, Westin

, Karlsson

and Furó

. 2008. Towards novel wood-based materials: Chemical bonds between lignin-like model molecules and poly(furfuryl alcohol) studied by NMR. Holzforschung 62: 709–713.

16.

Papadopoulos

and Hill

CAS

. 2002. The biological effectiveness of wood modified with linear chain carboxylic acid anhydrides against Coniophora puteana. Holz Roh Werkst. 60 (5): 329–332.

17.

Pilgard

, De Vetter

, Van Acker

. and Westin

. 2010. Toxic hazard of leachates from furfurylated wood: comparison between two different aquatic organisms. Environ. Toxicol. Chem. 29: 1067–1071.

18.

Ringman

, Pilgård

, Brischke

and Richter

. 2013. Mode of action of brown rot decay resistance in modified wood: a review. 2014. Holzforschung 68 (2): 239–246.

19.

Rowell

R M

. (edited). 2005. Handbook of wood chemistry and wood composites. Boca Raton: Taylor & Francis.

20.

Rowell

, Ibach

, McSweeny

and Nilsson

. 2009. Understanding decay resistance, dimensional stability and strength changes in heat-treated and acetylated wood. Wood Mater. Sci. Eng. 4 (1–2): 14–22.

21.

Rowell

, Simonson

, Hess

, Placket

, Cronshaw

and Dunningham

. 1994. Acetyl distribution in acetylated whole wood and reactivity of isolated wood cell wall components to acetic anhydride. Wood Fiber Sci. 26: 11–18.

22.

Venås

. 2008. A study of mechanisms related to the fungal decay protection rendered by wood furfurylation. Copenhagen: University of Copenhagen.

23.

Verma

and Mai

. 2010. Hydrolysis of cellulose and wood powder treated with DMDHEU by a hydrolase enzyme complex, Fenton's reagent, and in a liquid culture of Trametes versicolor. Holzforschung 64 (1): 69–75.