title: Investigation of Cr(VI) reduction and Cr(III) immobilization mechanism by planktonic cells and biofilms of Bacillus subtilis ATCC-6633.
abstract: In this study, we investigated the Cr(VI) uptake mechanism of planktonic cells and biofilms of Bacillus subtilis (B. subtilis) ATCC-6633. Data showed that the effect of planktonic cells on the Cr(VI) uptake was quite different from that of biofilms. Planktonic cells had strong ability of Cr(VI) reduction, while biofilms possessed a great potential of Cr(III) immobilization. For planktonic cells, 100 mg/L Cr(VI) could be completely reduced. Both exopolymeric substances and cytoplasmic extracts contributed to high capacity of Cr(VI) reduction. After the reduction, noticeable Cr(III) precipitates were accumulated on bacterial surfaces, but 37.5% Cr(III) still remained in the supernatant. For biofilms, the biofilm debris became the main active ingredient of the Cr(VI) reduction. However, only 20 mg/L Cr(VI) could be reduced probably because of unavailability of reducing active sites during the biofilm formation. Further studies showed that biofilms had a better Cr(III) immobilization capacity than planktonic cells with 100% Cr(III) immobilized. Moreover, for the first time, we proposed a strategy combining the advantages of both planktonic cells and biofilms, and a successful Cr(VI) removal from typical Cr(VI)-containing plating wastewater was achieved through a 10-L pilot-scale experiment.
authors.affiliation: Key Lab of Biopesticide and Chemical Biology, Fujian Agriculture and Forestry University, Ministry of Education, Fuzhou, Fujian 350002, PR China; State Key Lab of Structural Chemistry, Fujian Institute of Research on The Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Pan
authors.affiliation: State Key Lab of Structural Chemistry, Fujian Institute of Research on The Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China.
authors.forename: Zunjing
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Key Lab of Biopesticide and Chemical Biology, Fujian Agriculture and Forestry University, Ministry of Education, Fuzhou, Fujian 350002, PR China; State Key Lab of Structural Chemistry, Fujian Institute of Research on The Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Chen
authors.affiliation: State Key Lab of Structural Chemistry, Fujian Institute of Research on The Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China.
authors.forename: Yangjian
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: State Key Lab of Structural Chemistry, Fujian Institute of Research on The Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China.
authors.forename: Danmei
authors.initials: D
authors.lastname: Pan
authors.affiliation: Fuzhou No. 3 Middle School, Fuzhou, Fujian 350003, PR China.
authors.forename: Jiening
authors.initials: J
authors.lastname: Shao
authors.affiliation: State Key Lab of Structural Chemistry, Fujian Institute of Research on The Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China. Electronic address: zlin@fjirsm.ac.cn.
authors.forename: Zhang
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Key Lab of Biopesticide and Chemical Biology, Fujian Agriculture and Forestry University, Ministry of Education, Fuzhou, Fujian 350002, PR China. Electronic address: guanxfafu@126.com.
authors.forename: Xiong
authors.initials: X
authors.lastname: Guan
mesh_terms: D001412:Bacillus subtilis / Q000378:metabolism*; D001673:Biodegradation, Environmental; D018441:Biofilms / Q000254:growth & development*; D002857:Chromium / Q000378:metabolism*; D010933:Plankton / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D014874:Water Pollutants, Chemical; D002857:Chromium; C074702:chromium hexavalent ion
keywords: Bacillus subtilis; Biofilm; Chromium; Immobilization; Reduction