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Hydrolytic ability of laboratory enzyme preparations from fungus of the Penicillium genus was investigated using kraft pulp from nonbleached softwood and bleached hardwood cellulose as substrates. The enzyme preparations were shown to efficiently hydrolyze both softwood and hardwood cellulose. The yields of glucose and reducing sugars were 24-36 g/l and 27-37 g/l from 100 g/l of dry substrate in 48 h, respectively, and depended on the number of substrate grinding cycles.

The paper describes three Penicillium verruculosum 28K mutants with about threefold enhanced production of five industrially important carbohydrases. The two-stage fermentation process that we developed provided a further two- to threefold increase in the production of carbohydrases. Physiological and biochemical studies showed that the synthesis of all five carbohydrases is inducible. Carboxymethylcellulase, xylanase, and beta-glucanase are synthesized under a common regulatory control, as is evident from the concurrent increase in the synthesis of these enzymes in the presence of microcrystalline cellulose. The synthesis of avicelase and beta-glucosidase is evidently induced by other cellulose- and hemicellulose-containing compounds present in the fermentation medium and, hence, is regulated independently of the three aforementioned enzymes.

By gel chromatography and polyacrylamide gel disc-electrophoresis the component composition of the culture liquid separated from the mycelium was investigated. After elution from Sephadex G-75 column lipase activity was concentrated in one peak. Out of 13 electrophoretic mobile protein components only one split trioleate. The paper describes a method to isolate lipase from the native solution of the produced which involves enzyme precipitation at 40% saturation of the native solution with ammonium sulphate, dialysis of the resultant concentrate and selective sorption of pigment and protein admixtures on the cellulose anion exchanger. The method maker it possible to obtain a highly purified lipolytic enzyme with a specific activity of up to 15 000 lu/mg protein and to provide its 35--40% yield.

The effect of the nutrient medium and cultivation conditions on the chitin content in cell walls of mycelial fungi of the Penicillium genus was studied. The chitin accumulation was influenced by the composition and quantity of carbon and nitrogen sources, acidity of the medium, aeration rate and age of the culture. The highest content of chitin in the strains studied was no more than 4--5%. The paper discusses the potential use of the fungi P. digitatum 24 P, P. notatum 1 f, P. terikowskii and P. claviforme as protein producers. It describes the procedure for measuring chitin in cell walls of mycelial fungi.