Publications (2)3.68 Total impact
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Article: A typical endo-xylanase from Streptomyces rameus L2001 and its unique characteristics in xylooligosaccharide production.
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ABSTRACT: The activity of the extracellular xylanase produced by Streptomyces rameus L2001 against different xylans and xylooligosaccharides (XOS) was investigated. The main products of hydrolysis of birchwood xylan and oat-spelt xylan by the S. rameus L2001 xylanase were xylobiose (X2) and xylotriose (X3), suggesting that this is an endo-acting xylanase. This was confirmed by analysis of XOS degradation products. The enzyme hardly hydrolyzed X2 and X3, but hydrolyzed xylotetraose (X4) and xylopentaose (X5) producing mainly X2 and X3 through transglycosylation. Depending on the substrate, different quantities of reducing sugars were produced by the xylanase: 150 mg/g from corncob, 105 mg/g from bean culms, and 133 mg/g from bagasse. With the bagasse substrate, the xylanase yielded 2.36, 2.76, 2.03, and 2.17 mg/mL of X2, X3, X4, and X5, respectively. The structure of xylobiose and xylotriose from the hydrolysis of corncob xylan was identified by MS and NMR. The production of XOS from various agricultural wastes has potential industrial applications. This is the first report of XOS production by S. rameus L2001.Carbohydrate research 10/2012; 359:30-6. · 2.03 Impact Factor -
Article: Properties of an Alkaline-Tolerant, Thermostable Xylanase from Streptomyces chartreusis L1105, Suitable for Xylooligosaccharide Production.
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ABSTRACT: An extracellular xylanase was purified to homogeneity from a culture of Streptomyces chartreusis L1105 by a 2-step method of ammonium sulfate precipitation and carboxymethyl sepharose fast-flow chromatography (CMSFF). The xylanase was purified by 6.86-fold, with a recovery yield of 31.96%. The purified xylanase appeared as a single protein band on SDS-PAGE with a molecular mass of about 34.2 kDa. The optimum temperature and pH of the purified xylanase activity were 70 °C and 7.2 respectively. The xylanase was more stable under alkaline conditions and retained more than 80% activity after 30 min incubation at pH 6 to 10. It also showed specific activity towards different xylans. Hydrolysis of oat-spelt and corn-cob xylans by the xylanase yielded xylobiose and xylotriose as principle products without the formation of xylose. These properties indicate that the purified xylanase may potentially be useful in biotechnological applications, such as xylooligosaccharide preparation. This is the first report about the purification and characterization of a xylanase from S. chartreusis.Journal of Food Science 04/2012; · 1.66 Impact Factor
