title: Purification, characterization, and application of a thermostable dextranase from Talaromyces pinophilus.
abstract: Dextranase can hydrolyze dextran to low-molecular-weight polysaccharides, which have important medical applications. In the study, dextranase-producing strains were screened from various soil sources. The strain H6 was identified as Talaromyces pinophilus by a standard ITS rDNA analysis. Crude dextranase was purified by ammonium sulfate fractionation and Sepharose 6B chromatography, which resulted in a 6.69-fold increase in the specific activity and an 11.27% recovery. The enzyme was 58 kDa, lower than most dextranase, with an optimum temperature of 45 °C and an optimum pH of 6.0, and identified as an endodextranase. It was steady over a pH range from 3.0 to 10.0 and had reasonable thermal stability. The dextranase activity was increased by urea, which enhanced its activity to 115.35% and was conducive to clinical dextran production. Therefore, T. pinophilus H6 dextranase could show its superiority in practical applications.
authors.affiliation: Department of Pharmaceutical Engineering, School of Biological and Medical Engineering, Hefei University of Technology, Hefei, 230009, People's Republic of China.
authors.forename: Yu-Qi
authors.initials: YQ
authors.lastname: Zhang
authors.affiliation: Department of Pharmaceutical Engineering, School of Biological and Medical Engineering, Hefei University of Technology, Hefei, 230009, People's Republic of China.
authors.forename: Ruo-Han
authors.initials: RH
authors.lastname: Li
authors.affiliation: Department of Pharmaceutical Engineering, School of Biological and Medical Engineering, Hefei University of Technology, Hefei, 230009, People's Republic of China. hbzhang@hfut.edu.cn.
authors.forename: Hong-Bin
authors.initials: HB
authors.lastname: Zhang
authors.affiliation: Department of Pharmaceutical Engineering, School of Biological and Medical Engineering, Hefei University of Technology, Hefei, 230009, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Wu
authors.affiliation: Department of Pharmaceutical Engineering, School of Biological and Medical Engineering, Hefei University of Technology, Hefei, 230009, People's Republic of China.
authors.forename: Xue-Qin
authors.initials: XQ
authors.lastname: Hu
mesh_terms: D003470:Culture Media; D003910:Dextranase / Q000096:biosynthesis*; D003911:Dextrans / Q000737:chemistry; D005936:Glucans / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007218:Industrial Microbiology; D008970:Molecular Weight; D012988:Soil Microbiology; D032901:Talaromyces / Q000201:enzymology*
chemical_list: D003470:Culture Media; D003911:Dextrans; D005936:Glucans; D003910:Dextranase
keywords: Characterization; Dextranase; Purification; Talaromyces pinophilus; α-Glucan degradation