This study tested whether chemically modified versions of tyrosol, a natural compound found in olives and red wine, could boost beneficial gut bacteria better than the original form. Researchers gave mice three different versions: plain tyrosol, natural salidroside (tyrosol with glucose attached), and a lab-created version with galactose attached instead. The galactose version worked best, promoting the most beneficial bacteria like Bifidobacteria and reducing harmful bacteria, potentially offering health benefits similar to prebiotic supplements.