title: Cyclic utilization of HP-β-CD in the bioconversion of cortisone acetate by Arthrobacter simplex.
abstract: OBJECTIVE
  To establish a method for the recovery and reutilization of hydroxypropyl-β-cyclodextrin (HP-β-CD) to lower the cost of its industrial application in cortisone acetate bioconversion.
  
  
  RESULTS
  HP-β-CD is not degraded by Arthrobacter simplex CPCC140451 (ASP) resting cells and 96.4 % HP-β-CD could be recovered by isobutyl acetate extraction. Moreover, the inclusion ability of recovered HP-β-CD barely decreased. The saccharide metabolic and catalytic activities of ASP were greater in the aqueous phase after extracting with isobutyl acetate than other organic solvents. Cyclic utilization tests showed that cortisone acetate conversion ratio was 91.0 % after eight cycles and reached 95.7 % with 0.2-0.6 mM HP-β-CD. Furthermore, >90 % conversion ratio was reached per cycle through a co-cyclic-utilization method with HP-β-CD and immobilized ASP.
  
  
  CONCLUSIONS
  Cortisone acetate conversion ratio in the HP-β-CD cyclic-utilization method is promising for industrial applications. The method can also be expanded to other CDs and other hydrophobic compounds bioconversion.
authors.affiliation: Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, People's Republic of China.
authors.forename: Yanbing
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, People's Republic of China.
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.affiliation: Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, People's Republic of China.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, People's Republic of China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, People's Republic of China. minw@tust.edu.cn.
authors.forename: Min
authors.initials: M
authors.lastname: Wang
mesh_terms: D000073738:2-Hydroxypropyl-beta-cyclodextrin; D001173:Arthrobacter / Q000201:enzymology* / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism; D055162:Biocatalysis; D003348:Cortisone / Q000031:analogs & derivatives* / Q000096:biosynthesis; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D047392:beta-Cyclodextrins; D000073738:2-Hydroxypropyl-beta-cyclodextrin; D003348:Cortisone
keywords: Arthrobacter simplex; Bioconversion; Cortisone acetate; Cyclic-utilization; Hydroxypropyl-β-cyclodextrin