During growth on xylan and xylose Thermoanaerobacterium saccharolyticum B6A-RI produced endoxylanase, beta-xylosidase, arabinofuranosidase, and acetyl esterase, and the first three activities appeared to be produced coordinately. During nonlimiting growth on xylan, these enzyme activities were predominantly cell associated; however, during growth on limiting concentrations of xylan, the majorit...

Thermomonospora fusca BD25 produces relatively high levels of activity of endoxylanases. Only oat spelt xylan, RBB-xylan and birchwood xylan reacted with endoxylanases with the maximum specific activity of 47.65 U mg-1 protein on birchwood xylan. The endoxylanase remained stable up to 70 °C. At 60 °C endoxylanase activity showed stability (92 %) for 16 h, however it showed a half-life of 8 h at...

Cereal bran is one of the most common ingredients used for increasing the dietary fibre content of foods due to its low cost, availability, familiarity, functionality and acceptable sensory characteristics. Oat and rice bran were treated with different levels (0, 70 and 700 ppm) of an endoxylanase enzyme and added to cakes on 30% flour weight basis. Endoxylanase treatment significantly (P<0.05)...

A xylanolytic bacterium was isolated from the sediment of an aquarium. Based on the 16S rDNA sequence as well as morphological and biochemical properties the isolate was identified and denoted as Bacillus subtilis (B. subtilis) AQ1 strain. An endoxylanase-encoding gene along with its indigenous promoter was PCR amplified and after cloning expressed in E. coli. In E. coli the recombinant enzyme ...

The effect of substrate concentration, pH and cultivation time on the production of endoxylanase from Aspergillus awamori ZH-26 were optimized by statistical analysis using response surface methodology (RSM). Endoxylanase production was optimized by central composite rotary design. Statistical analysis of the results showed that the linear and quadratic terms of these three variables had signif...

Arabinoxylan (AX) is a major dietary fibre component found in a variety of cereals. Numerous health benefits of arabinoxylans have been reported to be associated with their solubility and molecular features. The current study reports the development of a functional bread using a combination of AX-enriched material (AEM) and optimal commercial endoxylanase. The total AX content of bread was incr...

Alkalophilic Bacillus sp. strain NG-27 produces a 42-kDa endoxylanase active at 70 degrees C and at a pH of 8.4. The gene for this endoxylanase was cloned and sequenced. The gene contained one open reading frame of 1,215 bases. An active site characteristic of the family 10 beta-glycanases was recognized between amino acids 303 and 313, with the active glutamate at position 310. Though highly t...

Direct bacterial conversion of the hemicellulose fraction of hardwoods and crop residues to biobased products depends upon extracellular depolymerization of methylglucuronoxylan (MeGAX(n)), followed by assimilation and intracellular conversion of aldouronates and xylooligosaccharides to fermentable xylose. Paenibacillus sp. strain JDR-2, an aggressively xylanolytic bacterium, secretes a multimo...

The economical production of fuels and commodity chemicals from lignocellulose requires the utilization of both the cellulose and hemicellulose fractions. Xylanase enzymes allow greater utilization of hemicellulose while also increasing cellulose hydrolysis. Recent metabolic engineering efforts have resulted in a strain of Thermoanaerobacterium saccharolyticum that can convert C(5) and C(6) sug...

An endoxylanase gene (PoxynA) that belongs to the glycoside hydrolase (GH) family 11 was cloned from a xylanolytic strain, Penicillium oxalicum B3-11(2). PoxynA was overexpressed in Trichoderma reesei QM9414 by using a constitutive strong promoter of the encoding pyruvate decarboxylase (pdc). The high extracellular xylanase activities in the fermentation liquid of the transformants were maintai...