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.com
Volume 8
Journal of Biotechnology & Biomaterials
ISSN: 2155-952X
Biotech Congress 2018 & Enzymology 2018
March 05-07, 2018
JOINT EVENT
20
th
Global Congress on
Biotechnology
3
rd
International Conference on
Enzymology and Molecular Biology
&
March 05-07, 2018 London, UK
From organic waste to biohydrogen: Approaches to enhance H
2
production by
Escherichia coli
Anna Poladyan, Karen Trchounian
and
Armen Trchounian
Yerevan State University, Armenia
B
ioconversion of organic waste into biohydrogen (H
2
) is a promising strategy both for inexpensive energy generation and
for simultaneous waste treatment. Different waste materials, such as biodiesel production waste glycerol, lignocellulosic
brewery spent grains (BSG), were used in the study. Lignocellulose, the most abundant renewable biomass with a huge amount
of worldwide annual production, is an ideal candidate for biomass and H
2
production. Glucose and xylose are the two most
abundant sugars derived from the breakdown of lignocellulosic biomass. Besides, Escherichia coli utilize many natural sugars
to form biomass and to produce H
2
. The later can be produced from formate decomposition via formate hydrogenlyase (FHL)
during
E. coli
glucose, xylose or glycerol fermentation. FHL consists of formate dehydrogenase H (FDH) and membrane-
associated four [Ni-Fe]-hydrogenase (Hyd) enzymes. The dilute acid pre-treatment method was used to hydrolyze the
lignocellulose structure and the BSG hydrolysate (BSGH) optimal conditions for bacterial growth and H
2
production were
designed.
E. coli
BW25113 parental strain and hydrogenase (Hyd) mutants with deletions of genes for key subunits of Hyd 1-4
(ΔhyaB, ΔhybC,ΔhycE, ΔhyfG)
, respectively, as well as
ΔhyaBΔhybC
double mutant biomass formation, redox potential kinetics
and H
2
production were investigated upon BSGH and glycerol utilization. Responsible Hyds for H
2
production upon both
glycerol and BSGH utilization were revealed. Approaches, such as mutations in Hyd genes, heavy metals supplementation,
pH, redox potential were used to enhance H
2
production upon both glycerol and BSGH utilization. The results obtained will
contribute the efficient and economical biomass and H
2
production.
apoladyan@ysu.amJ Biotechnol Biomater 2018, Volume 8
DOI: 10.4172/2155-952X-C2-092