title: Bacillus amyloliquefaciens biofilm as a novel biosorbent for the removal of crystal violet from solution.
abstract: Bacillus amyloliquefaciens biofilm shows promise for use in the control of soil-borne pathogens; however, it has never been used to treat dye-polluted wastewaters. Here, we propose the novel idea of using B. amyloliquefaciens biofilm for the adsorption of crystal violet (CV) from liquids. The relative contents of three main elements (C1s, O1s, and N1s) in the biofilm were 65.55%, 21.21%, and 13.24%, respectively. The results of Fourier transform infrared (FTIR) spectra and X-ray photoelectron spectroscopy revealed that the biofilm contained β-type heteropolysaccharide and proteins. The ruggedness of the biofilm surface due to embedded bacterial cells suggested potential adsorption sites for CV molecules. The maximum capacity for CV adsorption was 582.41mg/g, which is the largest value reported to date for any CV adsorbent. Blueshift occurred in the FTIR spectrum of CV-loaded biofilm as compared to that of virgin biofilm, confirming a physical adsorption process. We found that CV adsorption by biofilm was complex and resulted from intraparticle diffusion as well as surface adsorption. Our data also suggested that the process is exothermal and spontaneous, with micropore diffusion as the rate-limiting step. These findings provide a basis for using B. amyloliquefaciens biofilm as an efficient adsorbent for treating CV-polluted wastewaters.
authors.affiliation: College of Life Sciences, Zhejiang University, 310058 Hangzhou, Zhejiang, PR China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Sun
authors.affiliation: College of Life Sciences, Zhejiang University, 310058 Hangzhou, Zhejiang, PR China.
authors.forename: Cai
authors.initials: C
authors.lastname: Hui
authors.affiliation: College of Life Sciences, Zhejiang University, 310058 Hangzhou, Zhejiang, PR China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Chemical and Biomolecular Engineering, Vanderbilt University, 37235-1604 Nashville, TN, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Wan
authors.affiliation: School of Forestry and Biotechnology, Zhejiang Agriculture and Forestry University, 311300 Lin'an, Zhejiang, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhang
authors.affiliation: College of Life Sciences, Zhejiang University, 310058 Hangzhou, Zhejiang, PR China. Electronic address: yhzhao225@zju.edu.cn.
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000327:Adsorption; D001407:Bacillus / Q000737:chemistry* / Q000502:physiology; D001426:Bacterial Proteins / Q000737:chemistry; D018441:Biofilms; D004058:Diffusion; D005840:Gentian Violet / Q000302:isolation & purification*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D011135:Polysaccharides, Bacterial / Q000737:chemistry; D013816:Thermodynamics; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D001426:Bacterial Proteins; D005840:Gentian Violet; D011135:Polysaccharides, Bacterial; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Adsorption behaviors; Bacillus amyloliquefaciens; Biofilm; Crystal violet; Mechanism