Probiotics are the live microorganisms which when ingested in adequate amounts confer health benefits. The strains most frequently used as probiotics include Lactic acid bacteria, bifidobacteria and yeast Saccharomyces boulardii. However, several other bacterial strains are being investigated for potential probiotic value viz. Enterococcus, Streptococcus, Bacillus, among others. Significant therapeutic potential of probiotics has been demonstrated in several in vitro studies and that involving animal models and humans. Despite intense focus on probiotics research the mechanisms responsible for health benefits are not yet completely understood. Several important mechanisms have been proposed such as improvement of gut epithelial barrier function, Immunomodulatory effects, degradation of toxin receptors, competition for nutrients, production of inhibitory substances, antiproliferative effects, blocking of adhesion sites and modulation of gut microbiota. Bacterial cell components such as DNA or peptidoglycan may also be involved in functional mechanism of probiotics. Effectiveness of a probiotic for potential application as prophylactic or treatment agent for certain ailment is determined by its ability to possess all or most of these characteristic features. The current article describes the general functional mechanisms of probiotics.
Probiotics, health benefits, functional mechanisms