BIOCONVERSION OF COAL, LIGNIN, AND DIMETHOXYBENZYL ALCOHOL BY PENICILLIUM-CITRINUM

Bioconversion of alkali-soluble coal. sulfonated lignin. and dimethoxybenzyl alcohol (DMBA) by Penicillium citrinum was investigated with respect to the effects of (1) these compounds on growth and metabolism, and (2) the organism on the chemical nature of coal and DMBA. Alkali-soluble coal caused a slight enhancement of growth and metabolism; DMBA and lignin partially inhibited growth and metabolism. Both whole cells and cell-free extracts were capable of oxidation of DMBA to dimethoxybenzaldehyde. Whole cells demonstrated the capability of modifying alkali-soluble Beulah Zap and Ugljevik lignite coals by producing compounds that were of lower and higher molecular weight than the original coal. In vivo conversion of alkali-soluble Ugljevik coal resulted in a substantial decrease in the sulfur content of the coal (52% decrease). Cell-free extracts were able to degrade alkali-soluble Ugljevik lignite coal. The results suggest a potential usefulness of this microorganism for coal bioprocessing.