title: Mandelic acid chiral separation utilizing a two-phase partitioning bioreactor built by polysulfone microspheres and immobilized enzymes.
abstract: A novel two-phase partitioning bioreactor (TPPB) modified by polysulfone (PSF) microspheres and immobilized enzyme (novozym-435) was formed, and the resulting TPPB was applied into mandelic acid chiral separation. The PSF microspheres containing n-hexanol (named PSF/hexanol microspheres) was prepared by using the phase inversion method, which was used as the organic phase. Meanwhile, the immobilized enzyme novozym-435 was used as a biocatalyst. The water phase was composed of the phosphate buffer solution (PBS). (R, S)-Methyl mandelate was selected as the substrate to study enzymatic properties. Different reaction factors have been researched, such as pH, reaction time, temperature and the quantity of biocatalyst and PSF/hexanol microspheres added in. Finally, (S)-mandelic acid was obtained with an 80 % optical purity after 24 h in the two-phase partitioning bioreactor. The enantiomeric excess (eep) values were very low in the water phase, in which the highest eep value was only 46 %. The eep of the two-phase partitioning bioreactor had been enhanced more obviously than that catalyzed in the water phase.
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, Institute of Biochemical Engineering and Environmental Technology, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China, wangxy08@lzu.cn.
authors.forename: Xinyu
authors.initials: X
authors.lastname: Wang
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Cui
authors.forename: Xia
authors.initials: X
authors.lastname: Chen
authors.forename: Hao
authors.initials: H
authors.lastname: Zhu
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhu
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Li
mesh_terms: D019149:Bioreactors; D004800:Enzymes, Immobilized / Q000737:chemistry*; D005656:Fungal Proteins; D008049:Lipase / Q000737:chemistry*; D008333:Mandelic Acids / Q000737:chemistry / Q000302:isolation & purification*; D008863:Microspheres; D011108:Polymers; D013237:Stereoisomerism; D013450:Sulfones
chemical_list: D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D008333:Mandelic Acids; D011108:Polymers; D013450:Sulfones; C017662:polysulfone P 1700; C093667:Novozyme 435; D008049:Lipase; C037938:mandelic acid