T.K. Kirk

Bio: T.K. Kirk is an academic researcher. The author has an hindex of 3, co-authored 4 publications receiving 232 citations.

Fungal delignification and biomechanical pulping of wood

Abstract: This review article summarizes the results on microstructural changes and delignificantion, lignin-degrading enzyme systems, and biopulping of wood with lignin-degrading fungi. Biopulping, defined as the treatment of wood chips with lignin-degrading fungi prior to pulping, saves substantial amount of electrical energy during mechanical pulping, results in stronger paper, and lowers the environmental impact of pulping. Optical properties are diminished; however, brightness can be restored readily with peroxide bleaching. The economics of the process look attractive if the process can be performed in a chip-pile based system. Past work on biopulping had been minimal, however a comprehensive evaluation of biopulping at the Forest Products Laboratory suggests that biopulping has a good chance of commercial success.

Biomechanical pulping of loblolly pine with different strains of the white-rot fungus Ceriporiopsis subvermispora

Abstract: Des copeaux de P.taeda ont ete traites par cinq souches de Ceriporiopsis subvermispora pendant quatre semaines avant mise en pâte mecanique sur raffineur. Les pertes de poids des copeaux lors du traitement fongique ont ete de 4 a 7%. La consommation d'energie lors du defibrage et du raffinage a diminue de 21 a 37%. Les resistances a l'eclatement et au dechirement ont ete ameliorees respectivement de 33-46% et de 47-60%. La resistance a la traction n'a pas ete modifiee, de meme que l'opacite. La blancheur et le coefficient de diffusion de la lumiere ont ete diminues.

Biopulping. A glimpse of the future

Abstract: Acknowledgments This is the final report of Biopulping Consortium I, a 5-year research and information program involving the USDA Forest Service, Forest Products Laboratory (FPL), the University of Wisconsin (UW), the University of Minnesota, and industry. The objective of the Consortium research was to evaluate the technical feasibility of biopulping, defined as the fungal pretreatment of wood for pulping. The research focused on mechanical pulping, specifically on energy savings for the pulping itself, and on paper properties. Past work on biopulping has been minimal, but generally encouraging. In addition to the research objective, the Consortium served an information and education function, interfacing the industrial partners with developments in biotechnology. The overall conclusion of this 5-year research effort is that biopulping works. Through the use of the proper lignindegrading fungi, significant energy is saved in mechanical pulping, and paper strength properties are enhanced. Optical properties are diminished; however, brightness can be restored readily by bleaching. The process appears to be less polluting than chemi-mechanical processes, and the economics look favorable if the process can be performed in a chip pile-based system

Biopulping: A glimpse of the future. Forest Service research paper

Abstract: The objective of the consortium research was to evaluate the technical feasibility of biopulping, defined as the fungal pretreatment of wood for pulping. The research focussed on mechanical pulping, specifically on energy savings for the pulping itself, and on paper properties. Past work on biopulping has been minimal, but generally encouraging. In addition to the research objective, the Consortium served an information and education function, interfacing the industrial partners with developments in biotechnology.

Fungal laccase: properties and activity on lignin

Abstract: (Received 17 October 2000/Accepted 12 April 2001) The sources of ligninocellulose that occur in various forms in nature are so vast that they can only be compared to those of water. The results of several, more recent experiments showed that laccase probably possesses the big ability for "lignin-barrier" breakdown of ligninocellulose. The degradation of this compound is currently understood as an enzymatic process mediated by small molecules, therefore, this review will focus on the role of these mediators and radicals working in concert with enzymes. The fungi having a versatile machinery of enzymes are able to attack directly the "lignin- barrier" or can use a multienzyme system including "feed-back" type enzymes allowing for simulta- neous transformation of lignin and carbohydrate compounds.

Lignin-modifying enzymes in filamentous basidiomycetes--ecological, functional and phylogenetic review.

Abstract: Filamentous fungi owe powerful abilities for decomposition of the extensive plant material, lignocellulose, and thereby are indispensable for the Earth's carbon cycle, generation of soil humic matter and formation of soil fine structure. The filamentous wood-decaying fungi belong to the phyla Basidiomycota and Ascomycota, and are unique organisms specified to degradation of the xylem cell wall components (cellulose, hemicelluloses, lignins and extractives). The basidiomycetous wood-decaying fungi form brackets, caps or resupinaceous (corticioid) fruiting bodies when growing on wood for dissemination of their sexual basidiospores. In particular, the ability to decompose the aromatic lignin polymers in wood is mostly restricted to the white rot basidiomycetes. The white-rot decay of wood is possible due to secretion of organic acids, secondary metabolites, and oxidoreductive metalloenzymes, heme peroxidases and laccases, encoded by divergent gene families in these fungi. The brown rot basidiomycetes obviously depend more on a non-enzymatic strategy for decomposition of wood cellulose and modification of lignin. This review gives a current ecological, genomic, and protein functional and phylogenetic perspective of the wood and lignocellulose-decaying basidiomycetous fungi. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Potential Applications of the Oxidoreductive Enzymes in the Decolorization and Detoxification of Textile and Other Synthetic Dyes from Polluted Water: A Review

Abstract: Recently, the enzymatic approach has attracted much interest in the decolorization/degradation of textile and other industrially important dyes from wastewater as an alternative strategy to conventional chemical, physical and biological treatments, which pose serious limitations. Enzymatic treatment is very useful due to the action of enzymes on pollutants even when they are present in very dilute solutions and recalcitrant to the action of various microbes participating in the degradation of dyes. The potential of the enzymes (peroxidases, manganese peroxidases, lignin peroxidases, laccases, microperoxidase-11, polyphenol oxidases, and azoreductases) has been exploited in the decolorization and degradation of dyes. Some of the recalcitrant dyes were not degraded/decolorized in the presence of such enzymes. The addition of certain redox mediators enhanced the range of substrates and efficiency of degradation of the recalcitrant compounds. Several redox mediators have been reported in the literature, but very few of them are frequently used (e.g., 1-hydroxybenzotriazole, veratryl alcohol, violuric acid, 2-methoxy-phenothiazone). Soluble enzymes cannot be exploited at the large scale due to limitations such as stability and reusability. Therefore, the use of immobilized enzymes has significant advantages over soluble enzymes. In the near future, technology based on the enzymatic treatment of dyes present in the industrial effluents/wastewater will play a vital role. Treatment of wastewater on a large scale will also be possible by using reactors containing immobilized enzymes.