Madhu, K M; Dr.Chandrasekaran,M(Cochin University of Science and Technology, April , 2007)
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Abstract:
The beta-glucosidase enzyme purified from the marine fungus, Aspergillus
sydowii BTMFS 55 showed a good yield of enzyme production under solid state
fermentation. The statistical optimization of the media components revealed that
moisture content, concentration of peptone and inoculum are the major parameters
which supported the maximal enzyme production. The purified enzyme showed low
pH activity and stability, glucose tolerance and activation by ethanol. It could produce
ethanol from wheat bran and rice straw by simultaneous saccharification and
fermentation with yeast.The glucosidase purified from Aspergillus sydowii BTMFS 55
shows great potential for several biotechnological applications such as the production
of bio-ethanol from agricultural biomass and improvement in the aromatic character
of wines and fruit juices through the hydrolysis of flavour glucosidic precursors.
There is immense scope for the application of this marine fungus in the biofuel
production besides in other industries provided further studies are pursued in
exploiting this enzyme and the organism particularly scale up studies with respect to
application. There is also ample scope for cloning of the gene encoding beta-glucosidase
in domesticated hosts such as Pichia pastoris or S. cerevisiae that can produce ethanol
directly from cellulosic biomass.
Description:
Department of Biotechnology,
Cochin University of Science and Technology
Abraham, Mathew; Dr.Rajeev Kumar,S(Cochin University Of Science And Technology, December 12, 2012)
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Abstract:
Beta-glucosidases are critical enzymes in biomass hydrolysis process and is
important in creating highly efficient enzyme cocktails for the bio-ethanol industry.
Among the two strategies proposed for overcoming the glucose inhibition of commercial
cellulases, one is to use heavy dose of BGL in the enzyme blends and the second is to do
simultaneous saccharification and fermentation where glucose is converted to alcohol as soon as it is being generated. While the former needs extremely high quantities of
enzyme, the latter is inefficient since the conditions for hydrolysis and fermentation are
different. This makes the process technically challenging and also in this case, the
alcohol generation is lesser, making its recovery difficult. A third option is to use
glucose tolerant β-glucosidases which can work at elevated glucose concentrations.
However, there are very few reports on such enzymes from microbial sources especially
filamentous fungi which can be cultivated on cheap biomass as raw material. There has
been very less number of studies directed at this, though there is every possibility that
filamentous fungi that are efficient degraders of biomass may harbor such enzymes. The
study therefore aimed at isolating a fungus capable of secreting glucose tolerant β-
glucosidase enzyme. Production, characterization of β-glucosidases and application of
BGL for bioethanol production were attempted.
Description:
Biotechnology Division
National Institute for Interdisciplinary Science & Technology –CSIR
Thiruvananthapuram