Journal of Pure and Applied MicrobiologyVol. 4 No. 2

Optimization of Fermentation Parameters for Vitamin B12 Production using Propionibacterium freudenreichii sub sp. shermanii OLP-5 by Taguchi Method

Swarupa Rani Chiliveri, Thirupathaiah Yeruva, Smita Hasini Panda and Venkateswar Rao Linga

Department of Microbiology, Osmania University, Hyderabad- 500 007, India.

Received on 16 April 2010 and accepted on 30 May 2010



Vitamin B12 production by Propionibacterium freudenreichii sub sp. Shermanii was optimized using Taguchi orthogonal array (OA) design of experiment (DOE). An OA layout of L18 (21 x 37) was constructed with eight most influencing factors on vitamin B12 production, six factors like carbon, nitrogen, phosphate source, metal ion (Fe, Co) and inoculum size were selected based on ‘’one variable at a time approach’’ along with two other factors such as glucose (substrate) and DMBI (precursor). All the above factors except FeSO4. 7H2O (two level) were taken at three levels for proposed experimental design. Analysis was done by using Qualitek-4 software at bigger is better as quality character and obtained a predicted vitamin B12 yield of 24.662 mg/L with a specific combination of factors. The optimal levels of factors (FeSO4.7H2O,12.5 mg/L; Inoculum size,10%; (NH4)2HPO4, 0.1%; Glucose, 10%; DMBI, 0.025 g/L; Yeast extract, 1%, Sodium lactate, 1%; CoCl2.6H2O, 10 mg/L) obtained from designed methodology was further validated by confirmation experiment and the enhanced vitamin B12 (16.2 mg/L to 23.1 mg/L) was obtained from its unoptimized condition. Taguchi approach of DOE methodology proved to be efficient in evaluating the interaction of each factor individually and in combination.

Keywords : Orthogonal array, Propionibacterium freudenreichii sub sp. Shermanii, Taguchi DOE, Vitamin B12.