Roseburia intestinalis, a promising candidate for the development of next-generation probiotics, is a strictly anaerobic gut bacterium. Its sensitivity to oxygen primarily hinders large-scale production and the development and formulation of probiotic preparations. The addition of antioxidants could improve bacterial survival and stability in such formulations, but their direct effects on growth, metabolic activity and cell membranes remain poorly understood. In the experimental part of this thesis, we evaluated the response of the Roseburia intestinalis L1-952 strain to selected antioxidants under anaerobic conditions. Growth was monitored by measuring optical density at 654 nm, while metabolic responses were assessed by determining the proportions of H2 and CO2 in the gas phase and the concentrations of acetate, butyrate, lactate, and succinate. In addition, under selected conditions, potential changes in cell membranes were evaluated by analysing the profile of long-chain fatty acid methyl esters (FAMEs). The effects of the selected antioxidants on growth, the concentrations of metabolites produced, and changes in cell membrane composition reflected the chemical structure and concentration of the antioxidant compound. Propyl gallate and ferulic acid promoted growth at certain concentrations, while ascorbic acid slowed it down. Butyrate production was maintained for most antioxidants, while reduced production was observed at higher concentrations of curcumin. The long chain fatty acids analysis revealed compound-specific changes: ascorbic acid and curcumin increased the proportion of saturated fatty acids, while ferulic acid caused the smallest deviations from the control profile. Since all experiments were conducted under anaerobic conditions, the effects of the selected antioxidants on bacterial survival during oxygen exposure remain to be evaluated directly.
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