Microbial biotechnological approaches: renewable bioprocessing for the future energy systems

Abstract

The accelerating energy demands of the increasing global population and industrialization has become a matter of great concern all over the globe. In the present scenario, the world is witnessing a considerably huge energy crisis owing to the limited availability of conventional energy resources and rapid depletion of non-renewable fossil fuels. Therefore, there is a dire need to explore the alternative renewable fuels that can fulfil the energy requirements of the growing population and overcome the intimidating environmental issues like greenhouse gas emissions, global warming, air pollution etc. The use of microorganisms such as bacteria has captured significant interest in the recent era for the conversion of the chemical energy reserved in organic compounds into electrical energy. The versatility of the microorganisms to generate renewable energy fuels from multifarious biological and biomass substrates can abate these ominous concerns to a great extent. For instance, most of the microorganisms can easily transform the carbohydrates into alcohol. Establishing the microbial fuel technology as an alternative source for the generation of renewable energy sources can be a state of art technology owing to its reliability, high efficiency, cleanliness and production of minimally toxic or inclusively non-toxic byproducts. This review paper aims to highlight the key points and techniques used for the employment of bacteria to generate, biofuels and bioenergy, and their foremost benefits.

Keywords: Biofuel; Biomass; Enzymes; Fermentation; Metabolic engineering.

Fig. 1

Utilization of renewable feedstocks by microbial cell for the production of diverse bioproducts (Modified from Hollinshead et al. [7])

Fig. 2

Microbial production of biofuel biohydrogen (modified from Majidian et al. [28]). Chl-chlorophyll; PSI-Photosystem I; PSII-Photosystem II; Fd-ferridoxin; ATP-adenosine triphosphate; ADP-adenosine diphosphate; NADH- reduced form of nicotinamide adenine dinucleotide; NADH⁺- oxidized nicotinamide adenine dinucleotide