Effects of a Saccharomyces uvarum Cell-Based Preparation on Gut Microbial Ecology and Metabolic Activity in Adults Without Diagnosed Gastrointestinal Disease: A Randomized Placebo-Controlled Crossover Pilot Study

Background/Objectives: Yeast-based probiotic candidates are increasingly investigated as potential modulators of gut ecology, although evidence in healthy individuals remains limited. This randomized, single-blind, crossover study primarily evaluated the tolerability of ATECREM Serius containing Saccharomyces uvarum SERIUS strain (>1010 CFU/g) and explored its effect on human gut microbiota.