@article { ISI:000280972500010, title = {Enzymatic hydrolysis and ethanol production using xyloglucanase and debaromyces hansenii from tamarind kernel powder: galactoxyloglucan predominant hemicellulose}, journal = {Journal of Biotechnology}, volume = {148}, number = {4}, year = {2010}, month = {AUG}, pages = {233-239}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

The hydrolysis and ethanol production from tamarind kernel powder (TKP), a rich source of galactoxyloglucan (GXG) was investigated for the first time using xyloglucanase and thermotolerant Debaromyces hansenii. The acid hydrolysis of TKP with 2N H(2)SO(4) at 120 degrees C for 30 min yielded an overall saccharification of 94\% based on the total available carbohydrate content and further fermentation at 40 degrees C with thermotolerant D hansenii produced an ethanol yield of 0.35 g/g. A maximum hydrolysis of 55 and 78\% for GXG was obtained in 48 h at 50 degrees C using Thermomonospora xyloglucanase (TXy) and accellerase (TM) 1000, respectively. The synergistic effect of beta-galactosidase and xyloglucanase was demonstrated by the exogenous addition of beta-galactosidase to TXy which improved the overall hydrolysis of GXG by 30\%. The rate of hydrolysis of GXG with TXy and accellerase was increased by 15-20\% in the presence of chemical surfactants (tween 80 and toluene) or protein additive (BSA). The fermentation of enzymatic hydrolysates of GXG by TXy and accellerase with free cells at 40 degrees C produced an ethanol yield of 0.39 and 0.41 g/g whereas with immobilized cells produced 0.45 and 0.43 g/g, respectively, with a theoretical conversion efficiencies of 78-88\%. The immobilized yeast cells were reused six times at 40 degrees C with 100\% fermentation efficiency. (C) 2010 Elsevier B.V. All rights reserved.

}, keywords = {Ethanol, Galactoxyloglucan, Hydrolysis, Tamarind kernel powder, Thermotolerant yeast, Xyloglucanase}, issn = {0168-1656}, doi = {10.1016/j.jbiotec.2010.06.004}, author = {Menon, Vishnu and Prakash, Gyan and Rao, Mala} } @article { ISI:000287428900016, title = {Bioethanol production from renewable polymer lichenan using lichenase from an alkalothermophilic thermomonospora sp and thermotolerant yeast}, journal = {Fuel Processing Technology}, volume = {92}, number = {3}, year = {2011}, month = {MAR}, pages = {401-406}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Biomass feedstocks available decentrally will be more commodious for localized biorefinery approach than the exhaustive large scale and centralized plants driven by cost intensive technology. Lichen is present in a wide range of habitats in a distributed manner. A maximum hydrolysis of 73\%-76\% for lichenan from Cetraria islandica, Usnea barbata and Parmelia sp. were obtained in 24 h using lichenase from an alkalothermophilic Thermomonospora sp. wherein the hydrolysis was 100\% with commercial enzyme Accellerase (TM) 1000. The synergistic role of beta-glucosidase in lichenan hydrolysis was demonstrated by the exogenous addition of beta-glucosidase to Thermomonospora lichenase which resulted in complete hydrolysis. The hydrolysates of lichenan obtained using Accellerase or a cocktail of Thermomonospora lichenase and beta-glucosidase when fermented with free cells of Saccharomyces at 40 degrees C produced an ethanol yield of 0.45 g/g-0.48 g/g with theoretical conversion efficiencies of 93\%-96\%. The Ca-alginate immobilized yeast cells were reused eight times at 40 degrees C with 100\% fermentation efficiency. (C) 2010 Elsevier B.V. All rights reserved.

}, keywords = {Ethanol, Hydrolysis, Lichenan, Lichenase, Synergism, Thermotolerant yeast}, issn = {0378-3820}, doi = {10.1016/j.fuproc.2010.10.001}, author = {Menon, Vishnu and Divate, Rupesh and Rao, Mala} } @article { ISI:000319545800013, title = {Approach towards biocatalytic valorisation of barley beta-glucan for bioethanol production using 1,3-1,4 beta-glucanase and thermotolerant yeast}, journal = {International Biodeterioration \& Biodegradation}, volume = {82}, year = {2013}, month = {AUG}, pages = {81-86}, publisher = {ELSEVIER SCI LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

The exploitation of renewable resource containing polymers other than cellulose and hemicellulose are critically important for the feasibility of biofuel production. The potential of 1,3-1,4 glucan 4-gluconohydrolyase mediated saccharification of barley beta-glucan (BG) was investigated for ethanol production using thermotolerant Saccharomyces sp. A maximum hydrolysis of 71\% was obtained in 24 h using in-house produced 1,3-1,4 beta-glucanase from an alkalothermophilic Thermomonospora sp. whereas the hydrolysis was 100\% with Accellerase (TM) 1000. The synergistic effect of beta-glucosidase and 1,3-1,4 beta-glucanase was demonstrated by the exogenous addition of beta-glucosidase to Thermomonospora 1,3-1,4 beta-glucanase which resulted in complete hydrolysis of BG. The hydrolysates of BG obtained using Accellerase or a cocktail of Thermomonospora 1,3-1,4 beta-glucanase and beta-glucosidase when fermented with free cells of Saccharomyces at 40 degrees C produced an ethanol yield of 0.44 g g(-1) and 0.46 g g(-1) respectively and when fermented with immobilized cells produced a yield of 0.49 g g(-1). The Ca-alginate immobilized yeast cells were reused nine times at 40 degrees C with 100\% fermentation efficiency. The economics of barley-to-fuel ethanol program will ameliorate if in addition to barley starch, beta-glucan is also utilized. (c) 2013 Elsevier Ltd. All rights reserved.

}, keywords = {1, 3-1, 4 Glucan 4-gluconohydrolyase, Barley beta-glucan, Ethanol, Hydrolysis, Synergism, Thermotolerant yeast}, issn = {0964-8305}, doi = {10.1016/j.ibiod.2013.03.002}, author = {Divate, Rupesh and Menon, Vishnu and Rao, Mala} }