Production of Cellulases by Trichoderma, Aspergillus, and Penicillium: Optimization Strategies, Biomass Valorization, and Industrial Perspectives

Integrated bioprocess optimization of cellulase and xylanase production by Penicillium argillaceum using lignocellulosic agro-industrial residues

Production of Xylanase and Cellulase by Two Isolated Aspergillus Strains Through Solid-State Fermentation of Lignocellulosic Residues

Results revealed that substrate recalcitrance was a major limiting factor for enzyme production and that thermochemical pretreatment significantly improved substrate utilization.

Valorization of Oilseed Agro-Industrial Coproducts Through Optimized Lipase Production by Trichoderma sp. in Submerged Fermentation

This study integrates microbial biotechnology, bioprocess optimization, and circular bioeconomy principles to valorize oilseed agro-industrial coproducts as low-cost inducing substrates for lipase production. Palm kernel cake (PKC), canola cake, andiroba cake, and brewer’s spent grain were evaluated as carbon sources for extracellular lipase production by the wild-type strain Trichoderma sp. LEPM-711 under submerged fermentation. Qualitative screening in olive oil/rhodamine B medium confirmed the strain’s lipolytic potential. Among the substrates tested, PKC showed the strongest induction, reaching 4.68 U mL−1, and was therefore selected for nitrogen supplementation and statistical optimization. Peptone supplementation increased lipolytic activity to 8.41 U mL−1 after 72 h. A Plackett–Burman design identified CaCl2·2H2O, CoCl2·6H2O, and peptone as significant medium components, while response surface methodology established the optimal operational conditions as pH 6.0, 106 spores mL−1, and 2% (w/v) PKC. Under these conditions, the crude enzymatic extract reached 18.31 U mL−1 at pH 7.0 and 45 °C, corresponding to an approximately 3.9-fold increase over the initial PKC fermentation. These findings support the use of Trichoderma sp. LEPM-711 and oilseed coproducts as a sustainable platform for enzyme production and residue upgrading within applied natural sciences.

Comparing deconstruction of sugarcane bagasse by a coculture of thermophilic bacteria and a fungal cellulase system.

BACKGROUND Lignocellulosic biomass is a promising feedstock for sustainable bioethanol production due to its abundance, renewability, and high carbohydrate content. Among these feedstocks, sugarcane bagasse (SCB), a fibrous byproduct of sugar and ethanol mills, is particularly abundant in Brazil. However, the complex and recalcitrant structure of lignocellulose hinders its biological conversion into biofuels. There are different enzymatic architectures to overcome this challenge. Fungal enzyme systems rely on non-complexed cellulase components that act independently and are often used in combination with yeast fermentation in a simultaneous saccharification and fermentation (SSF) configuration. By contrast, thermophilic bacteria such as Clostridium thermocellum employ complexed cellulosome systems capable of highly efficient biomass deconstruction, which enables their application in Consolidated Bioprocessing (CBP). Although previous studies have compared these systems on various lignocellulosic feedstocks, no direct comparison exists for unpretreated sugarcane bagasse. This study aimed to compare carbohydrate solubilization between CBP with a coculture of thermophilic bacteria and SSF with a fungal enzyme-yeast system for the conversion of unpretreated SCB, and to assess the effect of particle size. RESULTS CBP consistently achieved higher carbohydrate solubilization than SSF across all particle sizes, with improvements ranging from 1.9- to 3.7-fold. CBP was also less affected by particle size variation, showing a drop of 0.52-fold in solubilization for particles sized 0.2-4.00 mm, compared to a 2.2-fold for SSF. A strong linear correlation between C6 and C5 sugar solubilization was observed for both strategies. Despite differences in solubilization, residual sugar concentrations were similar between systems. Neither increased enzyme loading nor improved conditions significantly improved SSF performance, indicating intrinsic limitations in the enzymatic hydrolysis of unpretreated SCB. CONCLUSIONS This study provides the first direct comparison of unpretreated SCB deconstruction mediated by a thermophilic bacterial culture to a fungal cellulase preparation in the presence of yeast. Higher carbohydrate solubilization is seen for the bacterial system regardless of particle size. These findings highlight the potential of CBP with thermophilic bacteria as an alternative to conventional strategies. The results also reinforce the importance of standardized metrics, such as fractional carbohydrate solubilization, for cross-study comparison.

Disclosing the production of fungal chitinases and proteases using insect by-products as substrates in solid-state fermentation.

BACKGROUND The world population is projected to reach nearly 9.7 billion by 2050, significantly increasing the demand for novel and sustainable protein sources. Edible insects, such as Tenebrio molitor, emerge as promising alternatives due to their high nutritional value, but adult insects and frass are direct and abundant by-products of this industry. This study aimed to valorize insect by-products through solid-state fermentation (SSF) to produce chitinases and proteases with high industrial value. RESULTS Various fungi were tested in SSF, with Phanerochaete chrysosporium CECT 2777 and Aspergillus uvarum MUM 08.01 standing out as the most efficient protease producers, while Aspergillus niger CECT 2088 showed higher chitinolytic activity. Maximum chitinase (53.3 U g-1) and protease (366 U g-1) production was achieved on the 11th and 9th day of SSF of frass and adult insects, respectively, allowing the optimization of fermentation time. Increasing the solid load in SSF up to 50 g dry weight (DW) of frass did not decrease chitinase production (47.8 U g-1) compared to using 10 g DW, while protease activity decreased 70% and 44% when the quantity of adult insects increased up to 50 g DW and 100 g DW, respectively. CONCLUSION This work is pioneering in demonstrating the great potential of reusing Tenebrio molitor by-products to obtain value-added chitinases and proteases through SSF, contributing to reducing waste accumulation of insect origin and promoting the development of a circular economy. © 2026 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Utilization of lignocellulosic biomass as sustainable feedstock for the bioproduction of n-butanol as an advanced biofuel: current progress and future perspectives

n-Butanol is a promising advanced biofuel and versatile platform chemical. However, its fermentative production by solventogenic clostridial strains remains economically limited by reliance on costly edible feedstocks of corn and sugarcane. Lignocellulosic biomass provides an abundant, non-food alternative, but its effective conversion necessitates pretreatment which inevitably generates weak acids, furan derivatives, and lignin-derived phenolic compounds. These by-products synergistically inhibit clostridial metabolism by disrupting pH balance, depleting NADH/NADPH, and compromising membrane integrity. To address this bottleneck, this review systematically examines the formation and inhibitory effects of these compounds, and then summarizes the recent strategies of metabolic engineering and co-culture for enhancing the tolerance of strains against various pretreatment-derived inhibitors. In addition, the review traces the progress of pretreatment technologies from conventional acid, alkaline, and physicochemical methods to emerging ionic liquids and deep eutectic solvents, and compares their influence on butanol fermentation performance. By linking lignocellulose pretreatment, inhibition mechanisms, metabolic engineering, and bioprocess engineering, this review provides a systems-level framework for designing more efficient lignocellulosic butanol pathways. Future research interests are also provided, including predictive modeling to control inhibitor generation, strain improvement for lignin-derived phenolic tolerance, techno-economic analysis and life-cycle assessment, and integrated lignin valorization, all aimed at advancing economically viable and sustainable biorefinery processes.