In order to determine how various treatments of wood affect the possible utilization of the material for aminal feed a simple inexpensive method of assay is required. In vitro digestibilities in which rumen fluid from a fistulated cow is used as an inoculum in a test tube is considered to be the best method for this determination. The method used by Iotech for many of their analyses -- in vitro cellulose digestibilities (IVCD) -- involves determination of cellulose in th wood samples before and after rumen fluid digestion and the percent loss of cellulose is considered to be cellulose digestibility. This method however had certain shortcomings. It did not take into account any loss or change of cellulose during the cook and explosion and did not account for the presence of digestible hemicelluloses and sugars in the exploded wood. A sample with high IVCD may have lost a great deal of hemicelluloses whereas one with a lower IVCD may have retained enough hemicelluloses to give a similar true digestibility. Dry matter digestibilities (DMD), which we are now doing, is a measure of the percent of material which is solubilized by the rumen microorganisms. This takes into account the cellulose, hemicelluloses and any sugars which may have been produced during the cook and are still present in the cooked wood. Thus it can be used as an additional analyses to the IVCD to obtain a measure of possible digestibility of the cooked wood by the animal.
PDF
Ajoutez cet article à votre liste de sélections pour demander le PDF - Add this item to your selection list to request the PDF
A literature review was conducted to obtain reliable, experimentally determined calorific data for the various components of Canadian tree species. Information was obtained for 48 tree species native to Canada and is presented in tabular form. For indigenous species, the overall mean calorific value was found to be 21.18 Mj/kg for softwood materials (i.e. stem wood, stem bark, foliage, etc.) compared to 19.35 Mj/kg for hardwoods. Variation between reported values for a component of a particular species was found to be generally less than 5% but, in some instances, exceeded 10%. Calorific data are also presented for hybrid poplar and for several foreign species commonly planted in Canada. It is recommended that experimental research be conducted to form a complete calorific value checklist which could be used to supplement Canadian biomass inventory data.
PDF
Ajoutez cet article à votre liste de sélections pour demander le PDF - Add this item to your selection list to request the PDF
Digestibility of wood and bark, and the by-products of the steaming process. Part I. Wood and bark digestibility. Part II. Adhesive properties of lignin derived from steamed hardwoods.
Over 100 strains of wood-rotting fungi were initially screened for their celllulase and B-glucosidase activities. Some of these strains were assayed for extracellular cellulase activity using a variety of different solid media containing carboxymethyl cellulose or acid swollen cellulose. The diameter of clearing of these plates gave an approximate indication of the order of cellulase activities obtained from culture filtrates of these strains. Trichoderma strains grown on Vogel's medium gave the higher cellulase yields. Culture filtrates from Trichoderma sp. E58 demonstrated the highest B-glucosidase activity giving a value of 1.1 IU/mg. A variety of different cellulose and pretreated wood substrates were hydrolysed using Trichoderma culture filtrates. The importance of the pretreament conditions and ensuing chemical extractions of the cellulosic substrates was demonstrated by the range of ethanol values obtained in simultaneous saccharification and fermentation experiments using Zymomonas mobilis or Saccharomyces cerevisiae. The rate of hydrolysis of the cellulosic substrates by Trichoderma culture filtrates, concentrated culture filtrates and whole cell cultures was compared. An ethanol value of 2.2% (W/V) was obtained from 5% solka floc using concentrated culture filtrates of Trichoderma and Z.mobilis or S.cerevisiae.
PDF
Ajoutez cet article à votre liste de sélections pour demander le PDF - Add this item to your selection list to request the PDF
The information presented in this report is a summary of the more relevant experiments which were carried out by the author while on sabbatical from the Royal Military College of Canada. The work was carried out under an agreement between the author and Forintek Canada Corporation. The area of research was the study of the applicability of whole cell and enzyme immobilization to the enzymatic hydrolysis of cellulosic materials. As the scientific literature adequately details the rationale for enzyme immobilization no discussion of it has been presented here. Rather, what is presented are the results of experiments showing that use of immobilized enzymes can enhance the hydrolysis of cellulose.
PDF
Ajoutez cet article à votre liste de sélections pour demander le PDF - Add this item to your selection list to request the PDF
Screening of highly cellulolytic fungi and the purification, identification and isolation of the cellulase and xylanase enzymes from these fungi as a prerequisite for future cloning studies