Ethanol Production from Lignocelluloses by Native Strain Klebsiella oxytoca THLC0409

Abstract

The native strain Klebsiella oxytoca THLC0409 was isolated from a lignocelluloses-degrading microflora. Preliminary investigations were conducted to obtain the optimal growth conditions of the strain. Batch operations were applied for producing ethanol from various lignocelluloses via direct microbial conversion (DMC). The strain THLC0409 was a naturally-occurring cellulolytic microorganism having high capability of utilizing celluloses (avicel, a-cellulose) and natural lignocelluloses (corncob, Napiergrass, purified bamboo, raw bamboo, rice straw). However, THLC0409 is an enteric bacterium lacking cellulase and xylanase activity. The ethanol productions varied depending on the compositions of substrate lignocelluloses. Under the optimal conditions, ethanol yields on corncob and Napiergrass reached 0.0623 and 0.0475 g g -1 , respectively, which were far higher than those on avicel (0.019 g g -1 ), a-cellulose (0.02 g g -1 ), purified bamboo (0.02 g g -1 ), raw bamboo (0.018 g g -1 ), and rice straw (0.016 g g -1 ). Moreover, ethanol yields on oat-extracted xylan and corncob-extracted xylan were 0.15 and 0.04 g g -1 , respectively.

Fungal-mediated consolidated bioprocessing: the potential of Fusarium oxysporum for the lignocellulosic ethanol industry

“…Efforts have so far been focused mainly on the second approach. The bacteria Z. mobilis (Linger et al 2010 ; Luo and Bao 2015 ), Escherichia coli (Ingram et al 1999 ; Tao et al 2001 ; Ko et al 2013 ) and Klebsiella oxytoca (Tran et al 2011 ; Wood et al 2005 ), and the yeasts S. Cerevisiae (Hong et al 2014 ; Xu et al 2014 ; van Zyl et al 2007 ), Pachysolen tannophilus (Slininger et al 1987 ), Pichia stipitis and Candida shehatae (Prior et al 1989 ) have been modified in order to improve their performance in CBP. But there are various difficulties and challenges in the conversion of a candidate microorganism using gene transfer technology.…”

A panoramic view of technological landscape for bioethanol production from various generations of feedstocks

“…It also can directly use cellobiose and cellotriose along with C5 and C6 sugars, thereby eliminating the use of β-glucosidase and xylosidase. Compared to Z. mobilis , and E. coli , K. oxytoca has a more comprehensive range of substrate utility [ 158 ].…”

Simultaneous Sachharification and Fermentation of Rice Residues and its Comparative Analysis for Bioethanol Production

“…Ethanol yield is a parameter that is calculated as the amount of ethanol produced per unit of substrate utilisation. Ethanol productivity is estimated as the amount of ethanol produced per unit of substrate utilised in one unit of time 16 .…”