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Three strains of white-rot fungi were tested in solid state fermentation and submerged culture to obtain enzymes for dyes biotransformation. Both sugarcane bagasse and dyes induced laccase and manganese peroxidase biosynthesis but laccase seems to be the main enzyme related to the decolourisation profiles. A variable behavior of strains was observed depending on inducers, fermentation system and characteristics of the strains. Crude enzyme of Earliella scabrosa obtained in solid state fermentation showed higher decolourisation percentage of Navy FNB and Red FN-3G dyes than Trametes maxima (13) and Ganoderma zonatum (B-18). T. maxima exhibited the best decolourisation percentage in submerged cultures supplemented with Navy FNB, Red FN- 3G and yellow P-6GS dyes. Growing biomass of T. maxima could supply other enzymes and mediators for dyes transformation. Peculiar behaviour was observed with Ganoderma zonatum (B-18), it had a similar dyes biodegradation in both liquid and solid bed fermentation and there was not positive correlation between ligninolytic enzymes production and decolourisation pattern. The employment of crude enzymes produced in solid bed of bagasse could be an attractive option for biological removal of textile dyes. [ABSTRACT FROM AUTHOR]

A locally soil-isolated strain of Trichoderma citrinoviride produced cellulase activity levels quite similar to the overproducing mutant T. reeSei (T. longibrachiatum) QM 9414 when grown in homogeneous cultures containing sugarcane straw. It was confirmed than the crude enzymatic extracts (filter paper enzyme, carboxymethylcellulase and ß-glucosidase) have similar traits to the reference strain. Both strains utilized more efficiently the ground substrate in relation to other pre-treatments assayed. Kinetics of growth in solid beds containing sugarcane straw showed than the fermentation stopped around 96–120 hours, obtaining the highest enzyme production (filter paper enzyme: 16 U/g ), and released a minimum of residual sugar (glucose and xylose, 5.032 mg/g1 ). The final product is characterized by a reduction in fibre content of the substrate (40.4 %) and an increase in cell protein (6.2 - 7.9 %). [ABSTRACT FROM AUTHOR]

Trichoderma citrinoviride, isolated from soil of Havana, Cuba, utilised sugarcane straw with high yields for cellulolytic enzyme in solid state fermentation. The solid bed containing natural zeolite supplies all mineral elements necessary for fungal growth and enzyme activity. Zeolite acted as a pump for nitrogen and mineral elements dosage and regulated pH of culture media at 5, optimal value for enzyme production. [ABSTRACT FROM AUTHOR]