Challenges in cellulase bioprocess for biofuel applications

Increasing population and industrialization caused increased demand for liquid fossil fuels which in turn increases the greenhouse gas emission. Bioethanol produced from lignocellulosic biomass via enzymatic route is a potential alternative to fossil fuels and is environmentally sustainable. Cellulases have been regarded as the limiting factor for bioethanol production from lignocellulosic biomass via enzymes. In the last few decades advances in bioprocesses led to reduction in the cost of cellulases by several folds, enabling bioethanol production to become cost-effective. This is the reason for existence of commercial plants for bioethanol production, however; still there are scope for further improvement in bioprocess for cellulase production and research is ongoing worldwide. Researchers face huge challenge while moving from flask and bioreactor research outcomes from a laboratory scale to the pilot scale production, which has been rarely discussed. This review will present those challenges and its probable solutions. Though commercial cellulases are available, it is highly required to have in-house cellulase production technology to be self-reliant. On-site and integrated cellulase production configuration is popular as it seems to be cost-effective. This review will address advances in bioprocesses and challenges for cellulase production which have surfaced in the last decade. • Cellulase bioprocess with fungal culture possess several challenges. • Integrated configuration is most attractive and cost-effective in present scenario. • Strain improvement paves the way for the cost effective and efficient cellulase. • Challenges of high solid loading biomass saccharification needs major attention too.