The aim of the project is selection and research of probiotic microorganisms and natural bioactive substances and their combinations aimed at studying their beneficial effects in health promotion and in the prevention of chronic diseases, especially cancer and cardiovascular diseases, metabolic syndrome and obesity based on demonstration of their modulation effect on intestinal microbiota, their anticarcinogenic, anti-atherosclerotic and immunomodulatory effects in experimental conditions in vitro and in vivo. Based on the results achieved, probiotic micro-organisms and biomodulating substances in kind will be selected, which could, as part of functional foods, be used to promote health and prevent diseases through the treatment of intestinal microbiota. The activities carried out within the project will allow the selection of the most effective substances of biotechnological and natural origin acting individually as well as in combinations with each other, supporting the concept of potentiated probiotics. It will pave the way for the development of more effective functional foods in preventing the emergence of new diseases, as well as the development of new practices at the level of society. The new knowledge gained will be applied in practice, minimising the negative effects of synthetic substances on the body and contributing to the reduction of health risks due to chronic diseases. The place of implementation of the project will be Pavol Jozef Šafárik University in Košice. The implementation of the project will create new jobs for the project, 1 patent application will be filed, 6 publications issued, and measures will be put in place to step up university-business cooperation. The number of existing researchers working in the R & D activities of the project will be 3.5. 1 foreign expert will participate in the project activities, who will work on the applicant’s project tasks. 1 research institution will be supported.