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This study investigated the impact of Candida tropicalis NITCSK13 on sugarcane bagasse (SCB) consolidated bioprocessing (CSB) using various parameters, such as pH, steam explosion (STEX) pretreatment, and temperature (at two different temperatures, cellulose hydrolysis and ethanol fermentation). The backpropagation neural network (BPNN) method simulated the optimal CSB conditions, achieving a maximum ethanol yield of 44 ± 0.32 g/L (0.443 g of ethanol/g of SCB) from STEX pretreated SCB within 48 h at 55 °C for cellulose hydrolysis and 33 °C for ethanol fermentation and pH 3.5. The simulated conditions were experimentally validated and showed an R 2 value of 0.998 and absolute average deviation (AAD) of 1.23%. The strain NITCSK13 also exhibited a high ethanol tolerance of 16% (v/v). The interactions between the inhibitors, cellobiose, furfural, and thermocellulase were assessed through molecular docking. The results revealed a maximum inhibitory constant of 3.7 mM for furfural against the endoglucanase (EnG) of Humicola insolens (2ENG) at 50 °C. Acremonium chrysogenum endoglucanase (5M2D) exhibited a maximum of 88.7 µM for cellobiose at 50 °C. The SWISS homology model of EnG from Candida viswanathii exhibited inhibitory effects similar to those of EnG from Thermoascus and Thermotoga, indicating that the moderately thermophilic yeast Candida sp. cellulase may be capable of efficiently tolerating inhibitors and could be a promising candidate for consolidated bioprocessing of cellulosic ethanol., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent to publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Synthetic dyes such as azo dyes are significant pollutants in the wastewater released from various textile industries. The low biodegradability and production from synthetic sources with high shelf life make azo dyes a challenging material for degradation. This study used chemically mutated Aspergillus terrus in the laccase production under solid-state fermentation using sugarcane bagasse. Initially, the wild-type strain produced a laccase activity of 4.12 U/mL. Later, the alkaline pretreatment of sugarcane bagasse showed a significant increase in laccase activity by 38.9%. Further, random mutagenesis treatment with 100 mM EMS generated a hyper laccase-producing strain with a 2.3-fold increment in laccase activity compared to the wild-type strain. The enzyme displayed optimal activity at pH 6.5 and 35 °C. The metal ions such as Fe 3+ (29.4 U/mL), Fe 2+ (20.8 U/mL) and Cu 2+ (18.05 U/mL) showed positive effects on laccase activity. The crude laccase was used to bioremediate Congo red, a prominent azo dye used in textile and pharmaceutical industries. The preliminary studies with a crude enzyme displayed 68.86% dye decolourization after 24 h of incubation. Additionally, with Taguchi orthogonal array optimization experiments, the maximal dye decolorization of 78.24% was achieved by maintaining crude enzyme concentration (20 U), dye concentration (25 mg/L) and pH 4.5.