Effects of prebiotics on the growth capability of lactobacillus plantarum L5 / Sayyidatus Solehah Rahim

This study using Box-Behnken design under response surface methodology with 15 experiments to optimize growth factors of Lactobacillus plantarum LS (L. plantarum LS) in de Man, Rogosa and Sharpe (MRS) carbohydrate-free medium supplemented with three different concentrations 0.5, 2.5, 4.5% (w/v) each of two prebiotics, namely corn starch and gum Arabic and a nonprebiotic, namely glucose in order to determined the effects of prebiotics on viability growth characteristics of L. plantarum LS. The cultivation of L. plantarum LS toward corn starch and gum Arabic were done anaerobically at 1 % inoculum in a temperature controlled incubator shaker (Lab-Line, USA) operated at 150 rpm for up to 24 h incubation in the shake flask. Based on cultivation of L. plantarum in MRS carbohydrate-free enriched with three substrates (corn starch, gum arabic and glucose) in difference concentrations (0.5, 2.5, 4.5% (w/v)) exhibited that there is a main significant effect toward the maximum measurement growth (OD620) and specific growth rates (µ) only on corn starch alone with p < 0.05 and p > 0.05 respectively based on ANOVA result and Pareto chart, while, the interaction effect in combination of substrates did not showed any significant different. In contrast with mean doubling time, there were no substrates showed significant result for the main and interaction effect. The optimum amount of substrates to achieve a predicted maximum 00620 of 1.4A, were found to be as follows: corn starch 0% (w/v); gum Arabic 3.25 % (w/v); and glucose 5 % (w/v). Similar as OD620 value, in presence of both glucose (2.5% (w/v)) and gum Arabic (2.5% (w/v)) with absence of corn starch (0% (w/v)), L.plantarum LS demonstrated the shortest mean doubling time (-5 minutes). However, L.plantarum LS has the highest specific growth rates (0.75 µ) with absence of corn starch (0% (w/v)) and gum Arabic (0% (w/v)) with presence of glucose (2.5% (w/v)). Thus, these results indicated that corn starch had significant effect when supplemented alone, however gum Arabic is more preferred prebiotic for the viability and growth of L. plantarum LS than corn starch. Thus, gum Arabic could be a potential to be as a prebiotic for L. plantarum LS for future synbiotic combination study.