Effect of the gastrointestinal environment on pH homeostasis of Lactobacillus plantarum and Lactobacillus brevis cells as measured by real-time fluorescence ratio-imaging microscopy

This study is the first to produce an in vitro GIT model enabling real-time monitoring of pH homeostasis of single cells in response to the wide range of pHex of the GIT. Furthermore, it was possible to observe the heterogeneous response of single cells. The technique can be used to determine the survival and physiological conditions of potential probiotics and other microorganisms during passage through the GIT.