d(GC) - Association of Biotechnology and Pharmacy
d(GC) - Association of Biotechnology and Pharmacy
d(GC) - Association of Biotechnology and Pharmacy
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Current Trends in <strong>Biotechnology</strong> <strong>and</strong> <strong>Pharmacy</strong><br />
Vol. 6 (2) 190-195 April 2012, ISSN 0973-8916 (Print), 2230-7303 (Online)<br />
Optimization <strong>of</strong> Xylanase Secretion from Paenibacillus<br />
macquariensis<br />
Meeta Sharma <strong>and</strong> Anil Kumar*<br />
School <strong>of</strong> <strong>Biotechnology</strong>, Devi Ahilya University, Kh<strong>and</strong>wa Rd., Indore-452001, India<br />
*For Correspondence - ak_sbt@yahoo.com<br />
Abstract<br />
A sporulating bacteria having potential to<br />
produce xylanase has been isolated from the soil<br />
mixed with petroleum products. The isolated<br />
bacteria retained violet color upon gram straining<br />
revealing its Gram positive nature. This strain<br />
was identified as Paenibacillus macquariensis<br />
based on biochemical characterization <strong>and</strong><br />
deposited in MTCC with an accession number<br />
RC1819. The bacteria showed growth at wide<br />
variability <strong>of</strong> pH ranging from pH 5.2 to 10.0 <strong>and</strong><br />
the temperature ranging from 25 to 37 o C. The<br />
optimum pH for xylanase production has been<br />
found to be in the range <strong>of</strong> pH 8.2 to 8.6 <strong>and</strong> the<br />
optimum temperature for xylanase production is<br />
found to be 37°C. It secreted xylanase in the<br />
culture medium (extra-cellular xylanase) in the<br />
presence <strong>of</strong> 2% xylan. It secreted nearly 4.50<br />
units <strong>of</strong> xylanase per ml <strong>of</strong> culture medium. The<br />
data revealed that Paenibacillus macquariensis<br />
has high potential for xylanase secretion <strong>and</strong> can<br />
be used for industrial applications.<br />
Introduction<br />
Plant cell wall is mainly composed <strong>of</strong><br />
cellulose <strong>and</strong> hemicelluloses <strong>and</strong> provides a<br />
protective barrier against the enzymatic attack<br />
<strong>of</strong> cellulases <strong>and</strong> xylanases (1). Xylan is a<br />
heterogeneous polymer composed <strong>of</strong> 1,4 linked<br />
β-D xylosyl residues. It is much abundant in<br />
nature being the major component <strong>of</strong><br />
hemicelluloses <strong>of</strong> monocotyledonous cell walls.<br />
The complete degradation <strong>of</strong> system requires a<br />
multi-step process involving xylanases <strong>and</strong><br />
190<br />
various xylan debranching enzymes viz. βxylosidase,<br />
acetylxylan-esterase, α-glucuronidase<br />
<strong>and</strong> α-arabino-furanosidase (2,3).<br />
Xylanases in conjunction with other<br />
enzymes viz. cellulases, glucanases <strong>and</strong><br />
proteases, are widely used in animal feed,<br />
brewing, food processing <strong>and</strong> waste treatment<br />
as well as in paper <strong>and</strong> pulp industries (4-6).<br />
Combined application <strong>of</strong> xylanase, β-1,3 <strong>and</strong> 1,4glucanases<br />
can reduce the intestinal viscosity <strong>of</strong><br />
feed for higher nutrition availability <strong>and</strong> improve<br />
the filtration rate <strong>and</strong> extraction yield in the<br />
brewing industry (7,8).<br />
Xylanase (EC 3.2.1.8) acts on β-1,4 xylan<br />
<strong>and</strong> splits β-1,4 glycosidic linkage r<strong>and</strong>omly (4,9).<br />
The products are xylose, xylobiose <strong>and</strong> xylooligosaccharides<br />
<strong>and</strong> these products are used<br />
as feedstock for food <strong>and</strong> fine chemicals (10). It<br />
is an industrially important enzyme having<br />
applications in paper industry for brightening the<br />
pulp, clarification <strong>of</strong> fruit juices (9,11-12). Use <strong>of</strong><br />
xylanase in paper industry is eco-friendly since<br />
chemicals used in paper industry cause pollution<br />
(13-15). Here, we reported isolation <strong>of</strong> a bacteria<br />
which has been identified as Paenibacillus<br />
macquariensis <strong>and</strong> has been given accession<br />
number RC-1219 by the MTCC, Ch<strong>and</strong>igarh. We<br />
also optimized the conditions for xylanase<br />
production by this bacteria.<br />
Materials <strong>and</strong> Methods<br />
Collection <strong>of</strong> samples: Soil samples were<br />
collected from different places <strong>of</strong> Indore (Madhya<br />
Optimization <strong>of</strong> Xylanase Secretion from Paenibacillus macquariensis