Adhesion Properties of Lactobacillus plantarum Dad-13 and Lactobacillus plantarum Mut-7 on Sprague Dawley Rat Intestine

Abstract

Adhesion capacity is considered one of the selection criteria for probiotic strains. The purpose of this study was to determine the adhesion properties of two candidate probiotics, <i>Lactobacillus plantarum</i> Dad-13 and <i>Lactobacillus plantarum</i> Mut-7. The evaluation included the hydrophobicity of the cell surface using microbial adhesion to hydrocarbons (MATH), autoaggregation, and the adhesion of <i>L. plantarum</i> Dad-13 and <i>L. plantarum</i> Mut-7 to the intestinal mucosa of Sprague Dawley rat, followed by genomic analysis of the two <i>L. plantarum</i> strains. <i>L. plantarum</i> Dad-13 and <i>L. plantarum</i> Mut-7 showed a high surface hydrophobicity (78.9% and 83.5%) and medium autoaggregation ability (40.9% and 57.5%, respectively). The exposure of both isolates to the surface of the rat intestine increased the total number of lactic acid bacteria on the colon compartment, from 2.9 log CFU/cm² to 4.4 log CFU/cm² in <i>L. plantarum</i> Dad-13 treatment and to 3.86 log CFU/cm² in <i>L. plantarum</i> Mut-7 treatment. The results indicate the ability of two <i>L. plantarum</i> to attach to the surface of the rat intestine. The number of indigenous <i>E. coli</i> in the colon also decreased when the compartment was exposed to <i>L. plantarum</i> Dad-13 and Mut-7, from 2.9 log CFU/cm² to 1 log CFU/cm². Genomic analysis revealed that both strains have genes related to adhesion properties that could play an important role in increasing the adherence of probiotics to the intestinal mucosa such as gene encoding fibronectin-binding protein, chaperonin heat shock protein 33 (Hsp33)<b>,</b> and genes related to the capsule and cell wall biosynthesis. Based on these findings, we believe that <i>L. plantarum</i> Dad-13 and <i>L. plantarum</i> Mut-7 have adhesion properties to the intestinal mucosa in the rat intestine model system. The present research will be essential to elucidate the molecular mechanism associated with adhesion in our two probiotic strains.