Optimization of
medium composition by response surface methodology for improving biomass yield of
Tetragenococcus halophilus CH6-2
Vu Oanh Thi-Kieu, Le Tuan and Le Thanh Ha
Res. J. Biotech.; Vol. 21(1); 143-153;
doi: https://doi.org/10.25303/211rjbt1430153; (2026)
Abstract
Tetragenococcus halophilus CH6-2 was proven to positively affect the sensory characteristics
of fish sauce. This study aims to optimize the medium components for enhancing the
biomass of T. halophilus CH6-2 for starter culture production using a statistical
method. A minimum-run resolution IV factorial design was used to screen the medium
component that significantly affected biomass yield. Three components, MgSO4, K2HPO4
and glucose, were selected for further optimization study using Box-Behnken design.
The optimal concentration after optimization was 2.58 g/L MgSO4.7H2O, 6.09 g/L K2HPO4
and 12.4 g/L glucose.
The obtained OD600 and cell dry weight on the optimized medium were 1.87- and 2.51-fold
increased, reaching 3.993 ± 0.034 and 1.450 ± 0.018 mg/mL respectively. The viable
cell counts in the optimized medium reached 11.56 log CFU/mL in 24 hours of cultivation
which was a two-log increase compared with 9.55 log CFU/mL after 48 hours in the
MRS medium. In conclusion, higher biomass could be obtained in a shorter time in
the optimized medium than in the MRS medium.
