[Frontiers In Bioscience, Elite, 9, 155-174, March 1, 2017]

Biomass breakdown: A review on pretreatment, instrumentations and methods

Preeti Vyas1, Ashwani Kumar1, Suren Singh2

1Metagenomics and Secretomics Research Laboratory, Department of Botany, Dr. Harisingh Gour University (A Central University), Sagar-470003, (M.P.), India, 2Enzyme Technology Research Group, Department of Biotechnology and Food Technology, Faculty of Applied Sciences, Durban University of Technology, Durban-4000, South Africa


1. Abstract
2. Introduction
3. Composition of Biomass
4. Key steps in conversion of lignocelluloses to bioethanol
4.1. Pretreatment technology: removing barriers for hydrolysis of lignocelluloses
5. Breaking the plant defense: the role of microbial enzymes
6. Fermenting the sugars released from biomass degradation
7. Instruments used in biomass assessment
8. Challenges of lignocellulosics conversion into bioethanol
9. Conclusions
10. Acknowledgements
11. References


Enzymatic breakdown of lignocellulosic biomass for liquid fuel production is a viable alternative to fossil fuels, due to its renewable and environmental friendly nature. Naturally, plants protect their cell wall polysaccharides by giving limited access to the cell wall degrading enzymes. Lignocellulose breakdown requires proper pretreatments that disrupt the close inter-component association between the constituents of the plant cell wall. For efficient biomass conversion, the choice of the correct pretreatment is important for removing the barriers to enhance access to microbial enzymes. Among the pretreatment methods available, biological pretreatment is a promising approach for biomass degradation as there are no inhibitors generated. Another significant area that needs attention is the development of methods that can qualitatively and quantitatively determine the degradation of biomass and product generation. More technological advancement would be required in the field of pretreatment technology and fermentation processes to make the whole process economical. Here, we review the recent developments in the field of lignocellulosics, role of various pretreatments, instruments & methods and role of microbial enzymes in biomass degradations.


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Key Words: Biomass; Lignocelluloses; Pretreatments; Saccharification; Microbial Enzymes; Bioethanol, Review

Send correspondence to: Ashwani Kumar, Metagenomics and Secretomics Research Laboratory, Department of Botany, Dr. Harisingh Gour University (A Central University), Sagar-470003, (M.P.), India, Tel: 91-7697432012, Fax: 91-7582264236, E-mail: ashwaniiitd@hotmail.com