title: Superparamagnetic poly(methyl methacrylate) beads for nattokinase purification from fermentation broth.
abstract: An effective method for purification of nattokinase from fermentation broth using magnetic poly(methyl methacrylate) (PMMA) beads immobilized with p-aminobenzamidine was proposed in this study. Firstly, magnetic PMMA beads with a narrow size distribution were prepared by spraying suspension polymerization. Then, they were highly functionalized via transesterification reaction with polyethylene glycol. The surface hydroxyl-modified magnetic beads obtained were further modified with chloroethylamine to transfer the surface amino-modified magnetic functional beads. The morphology and surface functionality of the magnetic beads were examined by scanning electron microscopy and Fourier transform infrared. An affinity ligand, p-aminobenzamidine was covalently immobilized to the amino-modified magnetic beads by the glutaraldehyde method for nattokinase purification directly from the fermentation broth. The purification factor and the recovery of the enzyme activity were found to be 8.7 and 85%, respectively. The purification of nattokinase from fermentation broth by magnetic beads only took 40 min, which shows a very fast purification of nattokinase compared to traditional purification methods.
authors.affiliation: Laboratory of Separation Science and Engineering, State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, P.O. Box 353, Beijing 100080, People's Republic of China.
authors.forename: Chengli
authors.initials: C
authors.lastname: Yang
authors.forename: Jianmin
authors.initials: J
authors.lastname: Xing
authors.forename: Yueping
authors.initials: Y
authors.lastname: Guan
authors.forename: Huizhou
authors.initials: H
authors.lastname: Liu
mesh_terms: D001550:Benzamidines / Q000378:metabolism; D005285:Fermentation; D005290:Ferric Compounds / Q000737:chemistry / Q000378:metabolism; D008280:Magnetics; D053758:Nanoparticles / Q000737:chemistry; D019904:Polymethyl Methacrylate / Q000737:chemistry* / Q000378:metabolism; D013381:Subtilisins / Q000302:isolation & purification*
chemical_list: D001550:Benzamidines; D005290:Ferric Compounds; C000499:ferric oxide; C006500:4-aminobenzamidine; D019904:Polymethyl Methacrylate; D013381:Subtilisins; C053771:nattokinase