ABSTRACT
Wild uses of non-renewable energy led to the global issue of the fuel crisis, but, contrary to this, everyone’s concern is the generation of sustainable fuel resources. Biofuel is playing a notable role, and under one umbrella, there are many types of biofuels such as biodiesel, bioethanol, biogas, and so on. Bioethanol blends with gasoline easily. Earlier, bioethanol was produced by corn and soy to get starch and sugar. But due to food insecurity, renewable sources are required. Lignocellulosic biomass, or agricultural waste, played a role in producing sugar and further production. There are so many ways, but pre-treatment is one of the most expensive and labour-intensive methods. During pre-treatment, several limiting factors called inhibitors, such as furan, butenol, ILs, alkanes and alkenes, are introduced. Clostridium, Saccharomyces cerevisiae, and Escherichia coli have been used to generate microbial tolerance. This chapter will give an insight into inhibitors and their inhibition mechanisms, microbial tolerance in biofuel production, such as random mutagenesis, adaptive laboratory evolution, in situ detoxification, heat shock proteins, and so on. An advanced technique such as CRISPR has been applied to microbial strain modification and tolerance. Presently, a lot of work is being done, but there is still a lot to be achieved in the future related to microbial strains’ tolerance and improved biofuel production.
