Optimizing the Enzymatic Hydrolysis of Bioflocculated Microalgae for Bioethanol Production Viviane Simon, João Felipe Freitag, Júlia Lorenzato da Silva, Luciane Maria Colla Processes, 2025 Spirulina platensis is a promising microalga, but biomass harvesting remains a challenge. Fungal bioflocculation offers a potential solution, facilitating the production of valuable bioproducts like bioethanol. Effective cell disruption methods, including physical-chemical and enzymatic treatments, can enhance biomass utilization. However, commercial enzymes are not optimized for microalgae, necessitating research on ideal operational conditions. This study evaluated physical and enzymatic processes to hydrolyze bioflocculated microalgae for bioethanol production. The microalga was harvested using a fungal bioflocculant produced via submerged fermentation. Biomass hydrolysis involved physical methods (autoclaving, ultrasound + autoclaving, ultrasound + gelatinization, and gelatinization) combined with enzymes (amylase, amyloglucosidase, cellulase, and xylanase), optimized for pH, temperature, and enzyme load. Hydrolysates were then used for bioethanol production. Results showed a microalgae harvest efficiency of 99.7% with a 1:8 fungus-to-microalgae ratio. Enzyme optimization identified ideal conditions (e.g., pH 4.5; 60 °C for amylase/amyloglucosidase, 70 °C for cellulase, and 50 °C for xylanase). Combined enzymatic treatments achieved approximately 70% hydrolysis efficiency, yielding 19.06 g/L glucose and 7.29 g/L ethanol (~79% conversion). Ethanol productivity was ~0.6 g per 1 g bioflocculated biomass L−1·hr. These findings highlight the potential of enzymatic hydrolysis for complex biomasses, although further studies are needed to refine enzyme applications for better biomass utilization.
Application of enzymes in the biodegradation of plastics Luciane Maria Colla, Alan Rempel, Viviane Simon, Gabrielle Berwian, Julia Catiane Arenhart Braun, et al. Environmental Hazards of Plastic Wastes Bioremediation Approaches for Environmental Clean Up, 2025
Enzymatic hydrolysis of food waste for bioethanol production Victória Dutra Fagundes, João Felipe Freitag, Viviane Simon, Luciane Maria Colla Revista Brasileira De Ciencias Ambientais, 2024 The concern for environmental sustainability and the rational use of natural resources drives the development of new technologies to better utilize energy sources, culminating in the use of waste for biofuel production. This approach is strategic, as the use of agro-industrial and food waste aligns with the concept of circular bioeconomy and food security, allowing for value addition to waste and reducing environmental liabilities. Bioethanol stands out as the most promising biofuel derived from food waste, considering its chemical composition rich in carbohydrates and fermentable sugars. The biotechnological conversion of biomass into bioethanol requires pretreatment steps to facilitate enzyme action during the hydrolysis process, a crucial stage for sugar release. However, it underscores the need to optimize enzymatic processes, especially regarding pH and temperature ranges for enzyme activity, to ensure efficiency in converting biomass into bioethanol. The aim is to understand the processes involved in the enzymatic hydrolysis of organic waste. The literature review included studies with recent advances on the enzymatic hydrolysis of food waste for the sustainable production of bioethanol, using the keywords “Biomass,” “Enzymatic hydrolysis,” “Bioethanol,” and “Food waste” or “Food residues”. The hydrolysis of food waste for bioethanol production highlights the necessity of selecting the most efficient and sustainable pretreatment techniques, aiming to minimize byproduct generation while fully utilizing the raw material. Additionally, the use of different classes of enzymes in consortium during the production processes is emphasized.
Enzymatic Hydrolysis of Microalgal Biomass Luciane Maria Colla, Viviane Simon, João Felipe Freitag, Victória Dutra Fagundes, Alan Rempel, et al. Biomass Hydrolyzing Enzymes Basics Advancements and Applications, 2024
