Comparation between Thermochemical Hydrolysis and Microbial Fermentation in Bioethanol Production

This review compares third- and fourth-generation bioethanol production methods, focusing on thermochemical hydrolysis of algae and microbial fermentation using genetically engineered yeast. Biofuels have emerged as a sustainable, carbon-neutral alternative to fossil fuels, driven by growing energy demands and environmental concerns. Algae-based thermochemical hydrolysis has demonstrated high efficiency, achieving up to 98% glucose conversion under optimized conditions with cellulase. In contrast, fourth-generation techniques employ engineered yeast strains optimized for glycerol fermentation, with reported ethanol yields reaching 47.4%. Each method presents distinct advantages: thermochemical hydrolysis offers scalability and speed, while microbial fermentation provides high selectivity and effective carbon utilization. This review concludes that combining both approaches may offer a more robust and sustainable solution for large-scale bioethanol production.