Optimization of lactobacillus plantarum L5 with gum arabic : statistical approach / Nor Liyana Mohamad Nor

Statistical approach using full-factorial design (32) and response surface methodology (RSM) analysis were used to study the main interaction effect between L. plantarum L5 and gum Arabic, a probiotic and prebiotic respectively. Three level concentration of L. plantarum L5 and gum Arabic were designed using design of experiment (DOE) with 5, 10 and 15% (w/v) and 1, 3 and 5% (w/v) respectively and supplemented in de Man Rogosa and Sharpe (MRS) carbohydrate-free medium. The experiment was conducted in different runs and anaerobically cultivated in 150 mL at 37°C for 24 hours. Only L. plantarum L5 concentrations has significant effect toward maximum cfu. Others responses such as specific growth rate (µ) and mean doubling time (Td) gave no significant effect either by concentrations of L. plantarum L5 or gum Arabic. Even the factors have no significant effect, but at maximum level of cfu, specific growth rate and doubling time give the optimal value of concentration of gum Arabic and L. plantarum L5 which are 2.01E+08 cfu/mL, 1.0 per hour and 0.68 minutes respectively.