Screening of Effective Medium Composition for the Cultivation of Lactobacillus plantarum and Lactobacillus reuteri Using Statistical Methods

This study was conducted to develop an economical optimum medium composition for the mass production of $Lactobacillus$ $plantarum$ and $Lactobacillus$ $reuteri$, livestock probiotics. Medium ingredient factors were selected on the basis of MRS broth composition, and the 15 ingredient variables were as follows: sucrose, glucose, molasses, yeast extract, corn steep liquor, soy peptone, dipotassium phosphate, manganese chloride, magnesium chloride, tween 80, sodium chloride, sodium acetate, ammonium citrate, sodium sulphate, and ferrous sulphate. The Plackett Burman design, consisting of 20 runs, was employed for the analysis of ingredient effects on cell growth of $L.$ $plantarum$ and $L.$ $reuteri$. As a result, sucrose, glucose, molasses, yeast extract, corn steep liquor, soy peptone, sodium acetate, and ammonium citrate positively influenced the growth of $L.$ $plantarum$. Additionally, yeast extract, soy peptone, $K_2PHO_4$, and tween 80 positively influenced the growth of $L.$ $reuteri$. Positive effects were found from sucrose, yeast extract, and soy peptone in the integrated analysis of the effects of both $L.$ $plantarum$ and $L.$ $reuteri$. Finally, effective medium components for both strains were found as follows: sucrose (20.0 g/l), glucose (5.0 g/l), soy peptone (11.0 g/l), yeast extract (5.0 g/l), $K_2PHO_4$ (0.2 g/l), $CH_3COONa$ (2 g/l), and $MgCl_2$ (0.02 g/l).

통계적 방법을 이용한 Lactobacillus plantarum과 Lactobacillus reuteri 의 유효 배지 성분의 탐색

본 연구는 가축용 생균제로서 이용성이 우수한 $Lactobacillus$ $plantarum$과 $Lactobacillus$ $reuteri$의 대량생산을 위한 경제적 최적 배지조성을 도출하기 위하여 수행되었다. 두 균주의 배양을 위한 배지성분 요인들은 유산균 배지로 알려진 MRS broth를 기준으로 하여, sucrose, glucose, molasses, yeast extract, corn steep liquor, soy peptone, dipotassium phosphate, manganese chloride, magnesium chloride, tween 80, sodium chloride, sodium acetate, ammonium citrate, sodium sulphate 및 ferrous sulphate 등 총 15가지를 선택하였다. 각 배지성분들이 각 균주들의 세포성장에 미치는 요인분석은 20개의 실험으로 구성된 Plackett-Burman design 방법을 이용하여 분석하였다. 그 결과 $L.$ $plantarum$의 성장에 있어서는 sucrose, glucose, molasses, yeast extract, corn steep liquor, soy peptone, sodium acetate, ammonium citrate 등이 긍정적인 효과(positive effect)를 나타내었다. $L.$ $reuteri$의 경우, yeast extract, soy peptone, $K_2PHO_4$, tween 80에서 수준간의 격차가 큰 긍정적인 효과가 나타났다. 두 가지 균주들에서 얻어진 표준화된 통합적 효과의 주 효과를 분석한 결과, sucrose, yeast extract, soy peptone에서 긍정적인 효과가 나타났다. 최종적으로 $L.$ $plantarum$과 $L.$ $reuteri$ 두 균주에 공통적으로 적용할 수 있는 유효 배지 성분들로 sucrose (20.0 g/l), glucose (5.0 g/l), soy peptone (11.0 g/l), yeast extract (5.0 g/l), $K_2PHO_4$ (0.2 g/l), $CH_3COONa$ (2 g/l) 및 $MgCl_2$ (0.02 g/l)를 선택하였다.