Lactobacillus paracasei-enriched vegetables containing health promoting molecules

It is currently recognized that the human microbiota, in particular microorganisms inhabiting the gastrointestinal (GI) tract, has a deep impact on normal physiology and health. Alteration of GI microbiota (dysbiosis) has been associated with the occurrence of a number of diseases, not only of the GI tract itself. Therefore, manipulation of the GI microbiota is considered a potentially suitable approach for maintaining health and preventing and/or treating relevant diseases. In this regard, a marked research and commercial interest has been increasing in the last decades for the development of products containing live probiotic microorganisms which have been defined by FAO and WHO as "live micro-organisms which, when administered in adequate amounts, confer a health benefit on the host" (FAO/WHO, 2001, 2002). Many commercial products, including fermented foods, food complements, and pharmaceutical preparations, contain bacterial strains belonging to Bifidobacterium and Lactobacillus species which are widely used as probiotics. Health benefits which have been claimed for probiotics include, for example, alleviation of intestinal bowel disease symptoms (Orel and Kamhi Trop, 2014), improvement of the normal microflora composition (Cha et al., 2012), pathogen inhibition by producing bactericidal substances and competing with pathogens for adherence to the intestinal epithelium (Liévin-Le Moal and Servin, 2014), reduction of serum cholesterol (Mistry, 2014), prevention of allergies (Enomoto et al., 2014), stabilization and enhancement of the gut mucosal and epithelial barrier function (Rao and Samak, 2013), improvement in the digestion of lactose in intolerant hosts (de Vrese et al., 2001), reduction of constipation symptoms (Yang et al., 2008), and most importantly, modulation of the immune system which can be considered as one of the most important mechanisms responsible for the beneficial effects of probiotic bacteria on human health (Borchers et al., 2009). Finally, an anticarcinogenic activity has also been attributed to probiotics (Kumar et al., 2010); in fact, for example, the regular consumption of probiotics has been associated with the reduction in specific fecal enzymatic activities, including that of ?-glucuronidase and ?-glucosidase involved in the generation of potentially carcinogenic metabolites in the colon. The chapter presents an overview of the latest information regarding the use of probiotic/protechnological Lactobacillus paracasei in vegetable foods containing bioactive molecules.