ORIGINAL PAPER Evaluation of adhesion properties of lactobacilli probiotic candidates Hana Kin ˇ ova ´ Sepova ´ 1 • Blanka Florova ´ 2 • Andrea Bilkova ´ 1 • Eva Drobna ´ 1 • Vı ´te ˇ zslav Br ˇezina 3 Received: 24 October 2017 / Accepted: 28 December 2017 / Published online: 13 February 2018 Ó Springer-Verlag GmbH Austria, part of Springer Nature 2018 Abstract Bacterial adhesion is a complex phenomenon implicated in the host-bacterial interaction that is pivotal for probiotic activity. Eight probiotic lactobacilli candidates (Lactobacillus reuteri, L. plantarum, L. mucosae, L. murinus) were screened for their ability to adhere to abiotic and biotic surfaces in vitro. Adhesion to hydrocarbons was used for hydrophobicity assessment. Three strains of L. reuteri and L. murinus C were evaluated as hydrophobic, others as intermediate. All tested strains were able to form the biofilm on polystyrene. L. mucosae D and L. reuteri E were tested for adhesion to epithelial cell lines (HeLa and Caco-2). Both were more adherent to HeLa than to Caco-2. The adhesivity degree in HeLa reached the highest value after 8 h of co-cultivation in both lactobacilli tested, then decreased. In Caco-2, adhesion was increased within 24 h from the beginning of the co-cultivation. Mucus-binding protein gene, implicated in adhesion, was detected in L. mucosae D. Therefore, the involvement of proteinaceous substances in binding process was investigated. Cells of L. mucosae D were digested by three proteolytic enzymes (proteinase K, pronase E, trypsin) and evaluated for time-dependent adhesivity changes to HeLa, Caco-2, and L929 cell lines. Results confirmed that proteins are most likely to play an important role in binding of lactobacilli to eukaryotic cells. One hour after treatment, L. mucosae D was able to overcome the effect of proteolytic cleavage. We assume that it was due to the restoration of its cell-surface binding structures. Co-cultivation of HeLa and L. mucosae D led to protuberance and communication channels formation in eukaryotic cells. Graphical abstract Keywords Lactobacillus Á Adherence Á Mucus-binding protein Á Electron microscopy Á Hydrocarbons Á Monolayers Introduction Bacterial adherence to the host mucosa and epithelial cells (ECs) is one of the most important prerequisites of probi- otic strains for host colonization [1]. It leads to direct interactions that may result in the competitive exclusion of pathogens and host immune response modulation. The adherence is a complex process of binding between the & Hana Kin ˇova ´ Sepova ´ kinovasepova@fpharm.uniba.sk 1 Department of Cell and Molecular Biology of Drugs, Faculty of Pharmacy, Comenius University in Bratislava, Bratislava, Slovakia 2 Faculty of Medicine in Pilsen, Biomedical Center, Charles University in Prague, Plzen ˇ, Czech Republic 3 Faculty of Fisheries and Protection of Waters, Institute of Complex Systems, University of South Bohemia in C ˇ eske ´ Bude ˇjovice, Nove ´ Hrady, Czech Republic 123 Monatshefte für Chemie - Chemical Monthly (2018) 149:893–899 https://doi.org/10.1007/s00706-017-2135-1