Enhanced vanillin production from eugenol by Bacillus cereus NCIM-5727.

Biovanillin production by a wild strain of Bacillus cereus NCIM-5727 is studied using eugenol as the precursor aiming to achieve maximum vanillin productivity. Based on shake flask optimization, molar yield and global volumetric productivity of vanillin reached up to 71.2% (6.6 gL-1) and 0.18 g(Lh)-1, respectively, at 36 h by resting cells of B. cereus NCIM-5727 at the optimum cell concentration of 3 gL-1 using eugenol concentration of 10 gL-1 at 37 ºC, buffer pH 7.0, buffer volume 10%, and shaking speed 180 rpm. Furthermore, small-scale optimization in a bioreactor at the controlled aeration rate of 0.5 Lmin-1, agitation rate of 210 rpm, and pH 7.0 enhanced the global volumetric productivity of vanillin up to 0.28 g(Lh)-1 at 25 h of bioconversion. The highest vanillin molar yield (75.2%) is reported using resting cells of B. cereus NCIM-5727 upon eugenol biotransformation and found stable for 10 h.