[Methods] Once faecal microbiota was inoculated and stabilized in the simgi®, a first digestion of extract (800 mg, equivalent to 522 mg of gallic acid) was carried out. After this, the system was washed, and then it was daily fed with L. plantarum CLC17 (6*1010 CFU/day). After 14 days, a second digestion of the grape extract (800 mg) was carried out. This experimental sequence was repeated twice. Metabolic activity was monitored by determining microbial-derived phenolic metabolites and ammonium production. In addition, microbial diversity measures such as bacterial richness and diversity index were calculated.

[Results] Feeding the simgi® with the extract activated the colonic metabolism leading to a battery of phenolic metabolites such as gallic acid, protocatechuic acid, 3-O-methylgallic acid, syringic acid, catechol and 3,4-dihydroxyphenylacetic acid, among others. In terms of microbial metabolism, the inclusion of L. plantarum caused a slight increase in the phenolic metabolism, especially in compounds of higher degree of polymerization, as well as, in the ammonium ion content. In addition, supplementation with L. plantarum CLC17 did not cause differences in bacterial diversity.

[Introduction] Human gut microbiota influences the bioavailability of dietary polyphenols, as intestinal microbes metabolize them into active phenolic metabolites. On the other hand, certain probiotic strains (i.e. Lactobacillus plantarum CLC17) have been shown to metabolize polyphenols in culture studies. Therefore, administration of these probiotics could be proposed as a nutritional strategy to improve the gut metabolism of polyphenols and enhance their health effects.

Resumen del trabajo presentado al IX Workshop on Probiotics, Prebiotics of the Spanish Society of Probiotics and Prebiotics (Sociedad Española de Probióticos y Prebióticos, SEPyP), celebrado en Zaragoza (España) del 15 al 16 de febrero de 2018.

[Objectives] To stabilize the probiotic strain L. plantarum CLC17 in the dynamic gastrointestinal simulator (simgi®), and to study its impact in the microbial metabolism of a commercial polyphenol extract from red grapes.

[Conclusions] These results open the possibilities of using the probiotic strain L. plantarum CLC17 as a food ingredient to improve the metabolism of dietary polyphenols

Peer reviewed