Assessment and evaluation of cellulase production using ragi (Eleusine coracana) husk as a substrate from thermo-acidophilic Aspergillus fumigatus JCM 10253

Unveiling fungal strategies: Mycoremediation in multi-metal pesticide environment using proteomics

Micropollutants, such as heavy metals and pesticides, inhibit microbial growth, threatening ecosystems. Yet, the mechanism behind mycoremediation of the pesticide lindane and multiple metals (Cd, Total Cr, Cu, Ni, Pb, Zn) remains poorly understood. In our study, we investigated cellular responses in Aspergillus fumigatus PD-18 using LC-MS/MS, identifying 2190 proteins, 1147 of which were consistently present under both stress conditions. Specifically, Cu-Zn superoxide dismutase and heat shock proteins were up-regulated to counter oxidative stress and protein misfolding. Proteins involved in intracellular trafficking, secretion, and vesicular transport; RNA processing and modification showed enhanced abundance and regulating stress response pathways. Additionally, haloalkane dehalogenase and homogentisate 1,2-dioxygenase played pivotal roles in lindane mineralization. Bioinformatics analysis highlighted enriched pathways such as Glyoxylate and dicarboxylate metabolism and Purine metabolism, that are crucial for combating adverse environments. We identified the hub protein 26 S proteasome regulatory subunit complex as potential biomarker and remedial targets for mycoremediation of wastewater, suggesting practical applications for environmental remediation.

Lignocellulolytic Biocatalysts: The Main Players Involved in Multiple Biotechnological Processes for Biomass Valorization

Human population growth, industrialization, and globalization have caused several pressures on the planet's natural resources, culminating in the severe climate and environmental crisis which we are facing. Aiming to remedy and mitigate the impact of human activities on the environment, the use of lignocellulolytic enzymes for biofuel production, food, bioremediation, and other various industries, is presented as a more sustainable alternative. These enzymes are characterized as a group of enzymes capable of breaking down lignocellulosic biomass into its different monomer units, making it accessible for bioconversion into various products and applications in the most diverse industries. Among all the organisms that produce lignocellulolytic enzymes, microorganisms are seen as the primary sources for obtaining them. Therefore, this review proposes to discuss the fundamental aspects of the enzymes forming lignocellulolytic systems and the main microorganisms used to obtain them. In addition, different possible industrial applications for these enzymes will be discussed, as well as information about their production modes and considerations about recent advances and future perspectives in research in pursuit of expanding lignocellulolytic enzyme uses at an industrial scale.

Biochemical Characterization of Thermostable Carboxymethyl Cellulase and β-Glucosidase from Aspergillus fumigatus JCM 10253

Second-generation biofuel production has emerged as a prominent sustainable and alternative energy. The biochemical properties of cellulolytic enzymes are imperative for cellulosic biomass conversion into fermentable sugars. In the present study, thermostable CMCase and β-glucosidase were purified and characterized from Aspergillus fumigatus JCM 10253. The enzymes were purified through 80% ammonium sulfate precipitation, followed by dialysis and DEAE-cellulose ion-exchange chromatography. The molecular masses of the purified CMCase and β-glucosidase were estimated to be 125 kDa and 90 kDa, respectively. The CMCase and β-glucosidase demonstrated optimum activities at pH 6.0 and 5.0, respectively. Their respective maximum temperatures were 50 and 60 °C. The cellulase activities were stimulated by 10 mM concentration of Ca²⁺, Ni²⁺, Fe²⁺, Mg²⁺, Cu²⁺, Mn²⁺, Zn²⁺, and Pb²⁺ ions. The CMCase activity was enhanced by surfactant Triton X-100 but marginally influenced by most inhibitors. The β-glucosidase retained its activity in the presence of organic solvents (30%) isoamyl alcohol, heptane, toluene, and ethyl acetate, while CMCase was retained with acetone during a prolonged incubation of 168 h. The K_m and V_max values of the two cellulases were studied. The properties of high thermostability and good tolerance against organic solvents could signify its potential use in biofuel production and other value-added products.