Conversion of Wheat Bran to Xylanases and Dye Adsorbent by .

Agro-byproducts can be utilized as effective and low-cost nutrient sources for microbial fermentation to produce a variety of usable products. In this study, wheat bran powder (WBP) was found to be the most effective carbon source for xylanase production by TKU045. The optimal media for xylanase production was 2% () WBP, 1.50% () KNO, 0.05% () MgSO, and 0.10% () KHPO, and the optimal culture conditions were 50 mL (in a 250 mL-volume Erlenmeyer flask), initial pH 9.0, 37 °C, 125 rpm, and 48 h. Accordingly, the highest xylanase activity was 6.393 ± 0.130 U/mL, 6.9-fold higher than that from un-optimized conditions. TKU045 secreted at least four xylanases with the molecular weights of >180, 36, 29, and 27 kDa when cultured on the WBP-containing medium. The enzyme cocktail produced by TKU045 was optimally active over a broad range of temperature and pH (40-70 °C and pH 5-8, respectively) and could hydrolyze birchwood xylan to produce xylobiose as the major product. The obtained xylose oligosaccharide (XOS) were investigated for 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and the growth effect of lactic acid bacteria. Finally, the solid waste from the WBP fermentation using TKU045 revealed the high adsorption of Congo red, Red 7, and Methyl blue. Thus, TKU045 could be a potential strain to utilize wheat bran to produce xylanases for XOS preparation and dye adsorbent.