title: Production of xylobiose from the autohydrolysis explosion liquor of corncob using Thermotoga maritima xylanase B (XynB) immobilized on nickel-chelated Eupergit C.
abstract: In this study, a thermostable recombinant xylanase B (XynB) from Thermotoga maritima MSB8 was immobilized on nickel-chelated Eupergit C 250L. This immobilized XynB was then used to hydrolyze the autohydrolysis explosion liquor of corncob (AELC) in a packed-bed enzyme reactor for continuous production of xylooligosaccharides, especially xylobiose. When tested in batch hydrolysis of AELC, the immobilized XynB still retained its relative activity of 92.5% after 10 cycles of hydrolysis at 90 degrees C. The immobilized XynB retained 83.6% of its initial hydrolysis activity even after 168 h of hydrolysis reaction at 90 degrees C and demonstrated a half-life time of 577.6 h (24 days) for continuous hydrolysis. HPLC showed that xylobiose (49.8%) and xylose (22.6%) were the main hydrolysis products yielded during continuous hydrolysis. Xylobiose was adsorbed on an activated charcoal column and eluted with a linear gradient of 15% (v/v) ethanol to yield xylobiose with 84.7% of recovery. Also, the purity of xylobiose was up to 97.2% as determined by HPLC. Therefore, the immobilized XynB was suitable for the efficient production of xylobiose from AELC. This is the first report on the immobilization of xylanase for xylobiose production.
authors.affiliation: Department of Biotechnology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
authors.forename: S S
authors.initials: SS
authors.lastname: Tan
authors.forename: D Y
authors.initials: DY
authors.lastname: Li
authors.forename: Z Q
authors.initials: ZQ
authors.lastname: Jiang
authors.forename: Y P
authors.initials: YP
authors.lastname: Zhu
authors.forename: B
authors.initials: B
authors.lastname: Shi
authors.forename: L T
authors.initials: LT
authors.lastname: Li
mesh_terms: D019149:Bioreactors / Q000382:microbiology; D002614:Chelating Agents / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D004187:Disaccharides / Q000096:biosynthesis* / Q000302:isolation & purification; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry; D005798:Genes, Bacterial; D006207:Half-Life; D006868:Hydrolysis; D009532:Nickel / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013696:Temperature; D020124:Thermotoga maritima / Q000201:enzymology* / Q000235:genetics; D013997:Time Factors; D014994:Xylose / Q000737:chemistry; D003313:Zea mays / Q000737:chemistry* / Q000382:microbiology
chemical_list: D002614:Chelating Agents; D004187:Disaccharides; D004800:Enzymes, Immobilized; D011108:Polymers; D011993:Recombinant Fusion Proteins; D009532:Nickel; C065843:Eupergit C; D014994:Xylose; D043364:Endo-1,4-beta Xylanases; C004173:xylobiose