title: Removing Bacillus subtilis from fermentation broth using alumina nanoparticles.
abstract: In this study, an efficient separation technology using Al2O3 nanoparticles (NPs) was developed for removing Bacillus subtilis from fermentation broth. The dosage of alumina nanoparticles used for separating B. subtilis increased during the culture process and remained stable in the stationary phase of the culture process. The pH of the culture-broth was also investigated for its effects on flocculation efficiency, and showed an acidic pH could enhance the flocculation efficiency. The attachment mechanisms of Al2O3 NPs to the B. subtilis surface were investigated, and the zeta potential analysis showed that Al2O3 NPs could attach to B. subtilis via electrostatic attachment. Finally, the metabolite content and the antibacterial effect of the fermentation supernatants were detected and did not significantly differ between alumina nanoparticle separation and centrifugation separation. Together, these results indicate a great potential for a highly efficient and economical method for removing B. subtilis from fermentation broth using alumina nanoparticles.
authors.affiliation: State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China; College of Marine Science, Shandong University (Weihai), Weihai 264209, PR China.
authors.forename: Dashuai
authors.initials: D
authors.lastname: Mu
authors.affiliation: College of Marine Science, Shandong University (Weihai), Weihai 264209, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Mu
authors.affiliation: College of Marine Science, Shandong University (Weihai), Weihai 264209, PR China.
authors.forename: Zhenxing
authors.initials: Z
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China; College of Marine Science, Shandong University (Weihai), Weihai 264209, PR China.
authors.forename: Zongjun
authors.initials: Z
authors.lastname: Du
authors.affiliation: State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China; College of Marine Science, Shandong University (Weihai), Weihai 264209, PR China. Electronic address: guanjun@sdu.edu.cn.
authors.forename: Guanjun
authors.initials: G
authors.lastname: Chen
mesh_terms: D000537:Aluminum Oxide; D000890:Anti-Infective Agents / Q000494:pharmacology; D001412:Bacillus subtilis / Q000302:isolation & purification*; D001709:Biotechnology / Q000295:instrumentation / Q000379:methods*; D003470:Culture Media / Q000494:pharmacology; D005285:Fermentation; D005427:Flocculation; D006863:Hydrogen-Ion Concentration; D053758:Nanoparticles / Q000737:chemistry*; D011506:Proteins / Q000032:analysis
chemical_list: D000890:Anti-Infective Agents; D003470:Culture Media; D011506:Proteins; D000537:Aluminum Oxide
keywords: Alumina nanoparticles; Bacillus subtilis; Flocculation; Removing bacteria