Abstract

                                Lignin biodegradation by Streptomyces is remarkable than basidiomycetes ligninolysis by the fact that degradation of lignin by Streptomyces results in the formation of value added intermediaries and products like APPL, low molecular weight phenols, humic like polycondensates. In the present investigation, composting of industrial wastes by Streptomyces showed that the pH of final compost was near neutral and a gain in all major plant nutrients, secondary nutrients as well as micronutrients was evident. The wide initial C/N ratio was radically reduced to around 20 per cent indicating good decomposition. Humic acid content was also substantially higher. Analysis of the water extract of compost sample showed that the compost had low AA ratio indicating the formation of a high molecular weight humic fraction. Polymerization studies with laccase on humic acid fraction of the compost, elucidated that a high molecular weight compound was formed as a product of lignin degradation.

Key words : Industrial solid wastes, Composting, C/N ratio, Streptomyces,