Optimization of an Industrial Medium and Culture Conditions for Probiotic <i>Weissella cibaria</i> JW15 Biomass Using the Plackett-Burman Design and Response Surface Methodology
Hyung‐Seok Yu, Na‐Kyoung Lee, Won‐Ju Kim, Do-Un Lee, Jongha Kim, Hyun‐Dong Paik
Abstract
The objective of this study was to optimize industrial-grade media for improving the biomass production of Weissella cibaria JW15 (JW15) using a statistical approach. Eleven variables comprising three carbon sources (glucose, fructose, and sucrose), three nitrogen sources (protease peptone, yeast extract, and soy peptone), and five mineral sources (K 2 HPO 4 , potassium citrate, Lcysteine phosphate, MgSO 4 , and MnSO 4 ) were screened by using the Plackett-Burman design. Consequently, glucose, sucrose, and soy peptone were used as significant variables in response surface methodology (RSM). The composition of the optimal medium (OM) was 22.35 g/l glucose, 15.57 g/l sucrose, and 10.05 g/l soy peptone, 2.0 g/l K 2 HPO 4 , 5.0 g/l sodium acetate, 0.1 g/l MgSO 4 7H 2 O, 0.05 g/l MnSO 4 H 2 O, and 1.0 g/l Tween 80. The OM significantly improved the biomass production of JW15 over an established commercial medium (MRS). After fermenting OM, the dry cell weight of JW15 was 4.89 g/l, which was comparable to the predicted value (4.77 g/l), and 1.67 times higher than that of the MRS medium (3.02 g/l). Correspondingly, JW15 showed a rapid and increased production of lactic and acetic acid in the OM. To perform a scale-up validation, batch fermentation was executed in a 5-l bioreactor at 37C with or without a pH control at 6.0 0.1. The biomass production of JW15 significantly improved (1.98 times higher) under the pH control, and the cost of OM was reduced by two-thirds compared to that in the MRS medium. In conclusion, OM may be utilized for mass producing JW15 for industrial use.