Xylanase production using inexpensive agricultural wastes and its partial characterization from a halophilic Chromohalobacter sp. TPSV 101

Abstract

A halophilic and alkali-tolerant Chromohalobacter sp. TPSV 101 with an ability to produce extracellular halophilic, alkali-tolerant and moderately thermostable xylanase was isolated from solar salterns. Identification of the bacterium was done based upon biochemical tests and 16S rRNA sequence. The culture conditions for higher xylanase production were optimized with respect to NaCl, pH, temperature, substrates and metal ions and additives. Maximum xylanase production was achieved in the medium with 20% NaCl, pH-9.0 at 40°C supplemented with 1% (w/v) sugarcane bagasse and 0.5% feather hydrolysate as carbon and nitrogen sources. Sugarcane bagasse (250 U/ ml) and wheat bran (190 U/ml) were the best inducer of xylanase when used as carbon source as compared to xylan (61 U/ml). The xylanase that was partially purified by protein concentrator had a molecular mass of 15 kDa approximately. The xylanase from Chromohalobacter sp. TPSV 101 was active at pH 9.0 and required 20% NaCl for optimal xylanolytic activity and was active over a broad range of temperature 40-80°C with 65°C as optimum. The early stage hydrolysis products of sugarcane bagasse were xylose and xylobiose, after longer periods of incubation only xylose was detected.

Investigation on lignocellulosic saccharification and characterization of haloalkaline solvent tolerant endo-1,4 β-d-xylanase from Halomonas meridiana APCMST-KS4

“…Likewise, Chromohalobacter sp. TPSV 101 isolated from the solar salt pans showed the optimum xylanase activity even at 20% NaCl concentration (Prakash et al, 2009). It was reported that metal ions are activators of enzymes.…”

“…Hpl-002 , Bacillus halodurans (Kumar and Satyanarayana, 2011) B. pumilus GESF-1 (Menon et al, 2010), B. subtilis ASH (Sanghi et al, 2010), Chromohalobacter sp. TPSV (Prakash et al, 2009), Bacillus sp. GRE7 (Kiddinamoorthy et al, 2008), Cellulomonas xavigena (Santiago-Hernández et al, 2007), Enterobacter sp.…”

Halophilic bacteria are colonizing the exhibition areas of the Capuchin Catacombs in Palermo, Italy

“…Species of these two genera have already been identified for the capability to degrade hemicelluloses (Govender et al 2009; Kui et al 2010; Prakash et al 2009). The strains phylogenetically most related to an uncultured clone from the microbiome showed an individual variation, some being positive and some negative in the cellulolytic test (Table 1).…”

Systematics of haloarchaea and biotechnological potential of their hydrolytic enzymes

“…b-xylanases (bÀ1,4-D-xylan xylanohydrolase, EC 3.2.1.8) and b-xylosidases (1,4-b-D-xylan xylohydrolase, EC 3.3.1.37) are involved in the hydrolysis of the xylan [241]. Xylanases hydrolyze xylans to produce mixtures of xylooligosaccharides which can be the substrates for bxylosidases for further hydrolysis [242].…”