Sugar alcohol chain length governs membrane permeability: structural disruption and osmotic consequences

Sugar alcohols are a class of low digestible carbohydrates that are commonly used as sweeteners and humectants in foods. Sugar alcohols of different chain lengths may have different effects on the structure and function of cell membranes, but their specific mechanisms of action and their relationship with osmosis have not been systematically studied. In this study, the effects of three sugar alcohols with different chain lengths, erythritol (Ery), xylitol (Xyl) and sorbitol (Sor), on the permeability of cell membranes were investigated using living cell membranes and artificial multilamellar vesicle (MLV) models. The results of fluorescence microscopy showed that Ery had the greatest effect on the structure of MLVs, resulting in significant deformation of MLVs. This was closely followed by Xyl and Sor, which had relatively little effect on the vesicle structure. In addition, cellular experiments showed that Ery failed to significantly increase intracellular reactive oxygen species (ROS) levels as well as maintain the cell membrane potential at the same concentration compared to Xyl and Sor, which enhanced membrane adsorption and slowed down the decrease of the membrane potential. These results suggest that sugar alcohols with different chain lengths have different permeation effects on biological membranes and provide a theoretical basis for understanding their functions in physiological environments.