Abstract
Forty streptomycetes were isolated from the soils of farms in Riyadh. Only three isolates (St-2, St-9, and St-25) exhibited cellulolytic-ligninolytic activity, with the St-9 isolate exhibiting the highest activity and identified as Streptomyces lazureus. The optimum environmental and nutritional conditions for maximum cellulolytic-ligninolytic activity were determined as fermentation batch of pH of 7.5, inoculum size of 200 mu L of bacterial suspension, incubation period of 7 d, and incubation temperature of 30 degrees C. In addition, the fermentation batch contained peptone and yeast extract as the best nitrogen and carbon sources, respectively. Cellulase and ligninase were purified via gel filtration column chromatography. The accumulated end-product of the fermentation process was glucose powder, which was subjected to a partial characterization process. The glucose powder appeared white, melted at 146 degrees C, was highly soluble in water, slightly soluble in ethanol, and insoluble in ethyl ether. The glucose solution appeared clear without precipitates and had a low electric conductivity of 15 mu S.cm-1.