Fructooligosaccharides fos

Resistance to gastric acid and bile was determined using a published method (Jawan et al. 2019 ). Log-phase bacterial cultures were incubated in PBS at pH 1.5, 3.0 and in MRSc broth with porcine bile (Sigma-Aldrich, USA) for 3 h at 37 °C. Bacterial growth was determined by measuring OD_{630 nm} every 3 h for 9 h on a SpectraMax Plus 384 microplate reader. The phenol resistance of lactobacilli was quantified by inoculating log-phase bacterial cultures at an OD_{630 nm} of 0.1 into new MRS containing 0 to 0.4% w/v phenol (Merck, Germany) and measuring OD_{630 nm} every 30 min for 12 h using a SpectraMax Plus 384 microplate reader (Jawan et al. 2019 ). For prebiotic utilization ability, three commercially available prebiotics, namely Inulin (Alfa Aesar, Germany), Fructooligosaccharides (FOS), and Maltodextrin (Sigma-Aldrich, USA) were evaluated using an established protocol (Zago et al. 2011 (link)). Dextrose (Daejung, South Korea) was used as a positive control.