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.
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