title: Production and characterization of an intracellular bioflocculant by Chryseobacterium daeguense W6 cultured in low nutrition medium.
abstract: A novel intracellular bioflocculant (named MBF-W6) produced by Chryseobacterium daeguense W6 cultured in low nutrition medium was investigated in this study. The effects of carbon source, nitrogen source, C/N ratio, initial pH, inoculum size, culture temperature and shaking speed on MBF-W6 production were studied. Chemical analysis showed that the purified MBF-W6 was mainly composed of 32.4% protein, 13.1% polysaccharide and 6.8% nucleic acid. Fourier-transform infrared (FTIR) spectroscopy indicated the presence of carboxyl, hydroxyl, and methoxyl groups. The elemental analysis of purified MBF-W6 revealed that the mass proportion of C, H, O, N and S was 40.92:6.53:44.01:8.53:1.01 (w/w) correspondingly. MBF-W6 had good flocculating rate in Kaolin suspension without any cation addition. The highest flocculating rate of 96.9% was achieved under the optimal conditions (bioflocculant dosage 1.2 mg l(-1), pH 5.6 and temperature 15 degrees C).
authors.affiliation: State Key Lab for Agrobiotechnology, Center of Biomass Engineering, Key Laboratory of Agro-Microbial Resource and Application, Ministry of Agriculture, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: WeiJie
authors.initials: W
authors.lastname: Liu
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
authors.forename: BaoZhen
authors.initials: B
authors.lastname: Li
authors.forename: HongLi
authors.initials: H
authors.lastname: Yuan
authors.forename: JinShui
authors.initials: J
authors.lastname: Yang
mesh_terms: D019149:Bioreactors; D002244:Carbon / Q000737:chemistry; D045247:Chryseobacterium / Q000201:enzymology*; D003470:Culture Media; D005285:Fermentation; D006859:Hydrogen / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007477:Ions; D008670:Metals / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D013455:Sulfur / Q000737:chemistry; D013696:Temperature; D018508:Water Purification / Q000379:methods
chemical_list: D003470:Culture Media; D007477:Ions; D008670:Metals; D011108:Polymers; D011134:Polysaccharides; D013455:Sulfur; D002244:Carbon; D006859:Hydrogen; D009584:Nitrogen; D010100:Oxygen