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The light-dependent metabolism of the white rot basidiomycete Cerrena unicolor FCL139 has already been demonstrated using transcriptomic and Biolog-based approaches. To further analyze the influence of light on C. unicolor wood degradation, we measured the activity of an array of CAZymes (carbohydrate-active enzymes) and enzymes involved in the redox system of fungal cells associated with lignolysis. Extra- and intracellular enzymatic extracts were obtained from solid-state ash sawdust C. unicolor cultures cultivated for 14 days under red, blue, green, or white light conditions, or in the dark. Light greatly influenced the synthesis of MnP, total cellulases, endo-1,4-β-glucanase, endo-1,4-β-xylanase, catalase, and superoxide dismutase. The production of MnP and catalase was evidently stimulated by white light. It is also worth noticing that blue light caused a gradual increase in the activity of total cellulases throughout the entire period of C. unicolor growth. Moreover, endo-1,4-β-glucanase showed the highest activity on day 13 of fungus cultivation and the production of laccase and β-glucosidase appeared to be the least influenced by light. However, the strongest activity of the endo-1,4-β-xylanase was observed in the dark. It seemed that light not only influenced the regulation of the synthesis of the wood-degrading enzymes at different levels, but also acted indirectly by affecting production of enzymes managing harmful lignin by-products causing oxidative stress. The ability of the fungus to decompose woody plant material is clearly influenced by environmental factors.

Three species of white rot fungi: Cerrena unicolor, Phlebia lindtneri and Pycnoporus sanguineus were cultured in two different media under five different lighting conditions: dark, white, red, blue, and green light. Laccase, cellobiose dehydrogenase, and protease activities were examined in the samples. Blue light efficiently boosted laccase synthesis in C. unicolor and P. sanguineus, whereas the highest activities (20 654 nkat/l) of P. lindtneri laccase were observed when this fungus was maintained in green light. On the contrary, the green light allowed obtaining the highest activities of cellobiose dehydrogenase of C. unicolor and P. lindtneri, while CDH of P. sanguineus seems to be dependent on white light. It is clearly visible that differences in protease activities are noticeable not only between the lights variants but also among the media used. However, high proteases activities are correlated with light variants inducing laccase in Lindeberg and Holm medium. Contrary to the cellulose-based medium, where they are weak in light variants that lead to high CDH activities.

The effect of supplementation of medium with rapeseed meal (RM) on production of biotechnologically important enzymes was investigated in submerged cultures of the white rot fungus Cerrena unicolor. The addition of RM (3.5% w/v) distinctly stimulated the activities of laccase, chitinase, and β-glucosidase. As compared to the control, the activities of chitinase, β-glucosidase, and laccase in the RM supplemented cultures were up to 4.1, 8.4, and 3.9 times higher, respectively. The results of the spectrophotometric and spectrofluorometric measurements were additionally confirmed by zymographic analysis of the samples. The level of sugars and phenolic compounds as well as the antioxidative ability of fungal preparations were also determined. The results obtained indicate that the submerged liquid fermentation of rapeseed meal can be proposed as an inexpensive and very effective method for biotechnological production of chitinase, β-glucosidase, and laccase by C. unicolor.