Degradation of low rank coal by Trichoderma atroviride ES11

A new isolate of Trichoderma atroviride has been shown to grow on low rank coal as the sole carbon source. T. atroviride ES11 degrades similar to 82% of particulate coal ( 10 g l-(1)) over a period of 21 days with 50% reduction in 6 days. Glucose ( 5 g l-(1)) as a supplemented carbon source enhanced the coal solubilisation efficiency of T. atroviride ES11, while 10 and 20 g l-(1) glucose decrease coal solubilisation efficiency. Addition of nitrogen [ 1 g l -(1) (NH4)(2)SO4] to the medium also increased the coal solubilisation efficiency of T. atroviride ES11. Assay results from coal-free and coal-supplemented cultures suggested that several intracellular enzymes are possibly involved in coal depolymerisation processes some of which are constitutive ( phenol hydroxylase) and others that were activated or induced in the presence of coal ( 2,3-dihydrobiphenyl- 2,3-diol dehydrogenase, 3,4-dihydro phenanthrene-3,4-diol dehydrogenase, 1,2-dihydro1,2-dihydroxynaphthalene dehydrogenase, 1,2-dihydro1,2-dihydroxyanthracene dehydrogenase). GC-MS analysis of chloroform extracts obtained from coal degrading T. atroviride ES11 cultures showed the formation of only a limited number of specific compounds ( 4-hydroxyphenylethanol, 1,2-benzenediol, 2-octenoic acid), strongly suggesting that the intimate association between coal particles and fungal mycelia results in rapid and near-quantitative transfer of coal depolymerisation products into the cell.