Potent In Vitro Activity of Citrus aurantium Essential Oil and Vitis vinifera Hydrolate Against Gut Yeast Isolates from Irritable Bowel Syndrome Patients-The Right Mix for Potential Therapeutic Use

Irritable bowel syndrome (IBS) is a functional disorder without any pathological alteration, in which the alterations of the / s ratio of the gut microbiota, the balance of pro and anti-inflammatory cytokines and the brain-gut-microbiome axis are important for the development and progression of IBS. The aim of the study was to identify natural products, including essential oils or hydrolates, which were contextually harmless for the gut beneficial strains (e.g. spp.) but inhibitory for the pathogenic ones ( spp.). The effectiveness of 6 essential oils and 2 hydrolates was evaluated using microbiological tests, carried out on 50 clinical isolates ( , and species) and 9 probiotic strains ( , , and ) and immunological and antioxidant assays. The study led to a mixture based on a 1/100 ratio of var. essential oil / cv Italia hydrolate able to contextually reduce, in a concentration-dependent manner, the ability of species to form hyphal filaments and have an interesting immunomodulatory and anti-oxidant action. This mixture can potentially be useful in the IBS treatment promoting the restoration of the intestinal microbial and immunological balance.