Assessment of cellulase production by Aspergillus niger using a closed-loop process (a circular strategy).

• Grant number: 23/15942-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2024
• End date: January 31, 2025
• Field of knowledge: Engineering - Chemical Engineering - Chemical Process Industries
• Principal Investigator: Rosineide Gomes da Silva Cruz
• Grantee: Paula Danesin Castellar
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The production of cellulolytic enzymes has attracted the attention of the scientific and industrial community in the ethanol production process from lignocellulosic biomass, the second-generation ethanol (2G). These enzymes are used as biocatalysts and they are responsible for converting cellulose and hemicellulose into monomeric fermentable sugars that will be bioconverted into ethanol. The enzymatic route has been shown a promising alternative to produce bioethanol from renewable energy sources. However, due to the highly ordered, water-insoluble nature, and high crystallinity degree of cellulose, the enzymatic depolymerization becomes a challenging task. It is necessary that the cellulolytic microorganisms produce a mix of different enzymes (the cellulase complex) that will be responsible for the complete biomass hydrolysis. Compared to the chemical route, the enzymatic one has shown a promising alternative. Many literature studies pointed out good efficiency cellulose conversion. Despite this route shows to be a friendly environmental alternative, the costs related to enzyme production are one of the main bottlenecks that need to be overcome to turn the process feasible. Thus, this project aims to contribute to the research focusing on enzyme production. The objective will be studying cellulase production employing a closed-loop process (a circular strategy). In this approach, the enzymatic extract from the first cultivation will be used in the next one to liquefy the biomass (bagasse). Then, the biomass liquefied by this enzymatic extract will be used as an inducer for enzyme production in the next assay, and so on until the process stabilization. The enzymatic extracts at the end of these circular cultivations would be used in experiments of bagasse liquefaction in conditions already defined in the literature. It would be expected to obtain extracts with high enzymatic activity at the end of the closed loop cultivation. Furthermore, it would be expected to obtain a mix of enzymes adequate for each substrate.