title: Production and characterization of fengycin by indigenous Bacillus subtilis F29-3 originating from a potato farm.
abstract: Fengycin, a lipopeptide biosurfactant, was produced by indigenous Bacillus subtilis F29-3 isolated from a potato farm. Although inhibiting the growth of filamentous fungi, the fengycin is ineffective against yeast and bacteria. In this study, fengycin was isolated from fermentation broth of B. subtilis F29-3 via acidic precipitation (pH 2.0 with 5 N HCl) followed by purification using ultrafiltration and nanofiltration. The purified fengycin product was characterized qualitatively by using fast atom bombardment-mass spectrometer, Fourier transform infrared spectrometer, ultraviolet-visible spectrophotometer, (13)C-nuclear magnetic resonance spectrometer and matrix assisted laser desorption ionization-time of flight, followed by quantitative analysis using reversed-phase HPLC system. This study also attempted to increase fengycin production by B. subtilis F29-3 in order to optimize the fermentation medium constituents. The fermentation medium composition was optimized using response surface methodology (RSM) to increase fengycin production from B. subtilis F29-3. According to results of the five-level four-factor central composite design, the composition of soybean meal, NaNO(3), MnSO(4)·4H(2)O, mannitol-mannitol, soybean meal-mannitol, soybean meal-soybean meal, NaNO(3)-NaNO(3) and MnSO(4)·4H(2)O-MnSO(4)·4H(2)O significantly affected production. The simulation model produced a coefficient of determination (R(2)) of 0.9043, capable of accounting for 90.43% variability of the data. Results of the steepest ascent and central composite design indicated that 26.2 g/L of mannitol, 21.9 g/L of soybean meal, 3.1 g/L of NaNO(3) and 0.2 g/L of MnSO(4)·4H(2)O represented the optimal medium composition, leading to the highest production of fengycin. Furthermore, the optimization strategy increased the fengycin production from 1.2 g/L to 3.5 g/L.
authors.affiliation: Graduate School of Biotechnology and Bioengineering, Yuan Ze University, Chung-Li, Taoyuan 320, Taiwan; E-Mails: e6501257@yahoo.com.tw (L.-C.W.); itispay@gmail.com (W.-C.C.); chensy@saturn.yzu.edu.tw (S.-Y.C.).
authors.forename: Yu-Hong
authors.initials: YH
authors.lastname: Wei
authors.forename: Li-Chuan
authors.initials: LC
authors.lastname: Wang
authors.forename: Wei-Chuan
authors.initials: WC
authors.lastname: Chen
authors.forename: Shan-Yu
authors.initials: SY
authors.lastname: Chen
mesh_terms: D001412:Bacillus subtilis / Q000254:growth & development / Q000378:metabolism*; D001709:Biotechnology / Q000379:methods; D003470:Culture Media / Q000737:chemistry; D005285:Fermentation; D055666:Lipopeptides / Q000096:biosynthesis / Q000737:chemistry*
chemical_list: D003470:Culture Media; D055666:Lipopeptides; C049972:fengycin