Influence of cell-free extracts of Bifidobacterium bifidum and Lactobacillus reuteri on proliferation and biofilm formation by Escherichia coli and Pseudomonas aeruginosa

  • O. V. Knysh I. I. Mechnikov Institute of Microbiology and Immunology of National Academy of Medical Sciences of Ukraine
  • O. Y. Isayenko I. I. Mechnikov Institute of Microbiology and Immunology of National Academy of Medical Sciences of Ukraine
  • Y. V. Voyda Kharkiv Medical Academy of Postgraduate Education
  • O. O. Kizimenko Ukrainian Medical Stomatological Academy
  • Y. M. Babych I. I. Mechnikov Institute of Microbiology and Immunology of National Academy of Medical Sciences of Ukraine
Keywords: probiotic derivatives; lactic acid bacteria; gram-negative bacteria; metabiotics.

Abstract

The development of new effective preparations for the correction of microecological disorders based on probiotic derivatives requires a comprehensive study of the biological activity of the latter. We studied the proliferative activity and biofilm formation by clinical isolates: Escherichia coli and Pseudomonas aeruginosa under the influence of cell-free extracts containing structural components and metabolites of the Bifidobacterium bifidum and Lactobacillus reuteri probiotic strains. Cell-free extracts were obtained from disintegrates and cultures of probiotics. Disintegrates were prepared by cyclic freezing-thawing of probiotic cell suspensions. The cultures were obtained by cultivating probiotic microorganisms in their own disintegrates. The obtained disintegrates and cultures were filtered. The proliferative activity of the test cultures was studied using the spectrophotometric microtiter plate method after an hour-long exposure in undiluted cell-free extracts and subsequent cultivation in a nutrient medium containing 30%vol of the studied extracts at 37 °C for 24 hours. The biofilm formation of the test cultures was studied with 30% vol content of cell-free extracts in the cultivation medium using the spectrophotometric microtiter plate method. All the studied extracts exerted a similar effect on the proliferative activity and biofilm formation by E. coli and P. aeruginosa. Exposure of the test cultures in all undiluted extracts during an hour led to a significant decrease in the optical density of the test samples: optical density of the test wells ranged from 36.5% to 49.8% of the control wells. The test cultures that were exposed to the extracts: filtrate of L. reuteri disintegrate (L), filtrate of В. bifidum disintegrate (B) and filtrate of В. bifidum culture, grown in В. bifidum disintegrate (MB) after dilution and subsequent cultivation over the next 24 hours completely restored the ability to proliferate. The proliferative activity of the test cultures that were exposed to the extracts: filtrate of L. reuteri culture, grown in L. reuteri disintegrate (ML) and filtrate of L. reuteri culture, grown in L. reuteri disintegrate supplemented with 0.8 M glycerol and 0.4 M glucose (MLG), was significantly inhibited after dilution and subsequent cultivation. The inhibition indices calculated for the ML extract were: 25.9% (E. coli) and 53.0% (P. aeruginosa). Inhibition indices calculated for the MLG extract were: 62.0% (E. coli) and 96.9% (P. aeruginosa). MLG extract had more pronounced inhibitory effect on the proliferation of the test cultures than ML extract. All the studied extracts exerted significant inhibitory effect on the biofilm formation of the test cultures. Analysis of the results of the study shows that cell-free extracts of L. reuteri culture grown in its disintegrate without supplementation or supplemented with glycerol and glucose have the highest antimicrobial activity and can be used as metabiotics to prevent overgrowth of potentially pathogenic bacteria, as well as inoculation and proliferation of pathogenic gram-negative bacteria in the gastrointestinal tract. They can be used alone or in combination with cellular probiotics to enhance their probiotic action. This study encourages further careful investigation of the biochemical composition of cell-free extracts and clarifying the mechanism of their action.

References

Bitto, N., & Kaparakis-Liaskos, M. (2017). The therapeutic benefit of bacterial membrane vesicles. International Journal of Molecular Sciences, 18(6), 1287.

Britton, R. A. (2017). Lactobacillus reuteri. In: Floch, M., Ringel, Y., & Walker, W. (Eds.). The microbiota in gastrointestinal pathophysiology: Implications for human health, prebiotics, probiotics, and dysbiosis. Academic Press, London. Pp. 89–97.

Carding, S., Verbeke, K., Vipond, D. T., Corfe, B. M., & Owen, L. J. (2015). Dysbiosis of the gut microbiota in disease. Microbial Ecology in Health and Disease, 26(1), 26191.

De Freitas, M. B., Moreira, E. A. M., Tomio, C., Moreno, Y. M. F., Daltoe, F. P., Barbosa, E., Neto, N. L., Buccigrossi, V., & Guarino, A. (2018). Altered intestinal microbiota composition, antibiotic therapy and intestinal inflammation in children and adolescents with cystic fibrosis. PLoS One, 13(6), e0198457.

Fuentes, S., & de Vos, W. M. (2016). How to manipulate the microbiota: Fecal microbiota transplantation. In: Microbiota of the human body. Advances in experimental medicine and biology. Springer, Cham. Pp. 143–153.

Gladysheva, I. V. (2014). Antagonisticheskaia aktivnost korinebakterii [Antagonistic activity of corynebacteria]. Vestnik OGU, 174, 16–19 (in Russian).

Gomaa, E. Z. (2013). Antimicrobial and anti-adhesive properties of biosurfactant produced by lactobacilli isolates, biofilm formation and aggregation ability. The Journal of General and Applied Microbiology, 59(6), 425–436.

Gomes, T. A. T., Elias, W. P., Scaletsky, I. C. A., Guth, B. E. C., Rodrigues, J. F., Piazza, R. M. F., Ferreira, L. C. S., & Martinez, M. B. (2016). Diarrheagenic Escherichia coli. Brazilian Journal of Microbiology, 47, 3–30.

Greifová, G., Májeková, H., Greif, G., Body, P., Greifová, M., & Dubničková, M. (2017). Analysis of antimicrobial and immunomodulatory substances produced by heterofermentative Lactobacillus reuteri. Folia Microbiologica, 62(6), 515–524.

Halmos, T., & Suba, I. (2016). Physiological patterns of intestinal microbiota. (The role of dysbacteriosis in obesity, insulin resistance, diabetes and metabolic syndrome). Orvosi Hetilap, 157(1), 13–22.

Harmsen, H. J. M., & de Goffau, M. C. (2016). The human gut microbiota. In: Schwiertz, A. (Ed.). Microbiota of the human body. Advances in experimental medicine and biology. Springer, Cham. 902, 95–108.

Hesari, M. R., Darsanaki, R. K., & Salehzadeh, A. (2017). Antagonistic activity of probiotic bacteria isolated from traditional dairy products against E. coli O157: H7. Journal of Medical Bacteriology, 6(3–4), 23–30.

In Lee, S. H., Barancelli, G. V., de Camargo, T. M., Corassin, C. H., Rosim, R. E., da Cruz, A. G., Cappato, L. P., & de Oliveira, C. A. F. (2017). Biofilm-producing ability of Listeria monocytogenes isolates from Brazilian cheese processing plants. Food Research International, 91, 88–91.

Jorgensen, M. R., Kragelund, C., Jensen, P. O., Keller, M. K., & Twetman, S. (2017). Probiotic Lactobacillus reuteri has antifungal effects on oral Candida species in vitro. Journal of Oral Microbiology, 9(1), 1274582.

Karimi, S., Rashidian, E., Birjandi, M., & Mahmoodnia, L. (2018). Antagonistic effect of isolated probiotic bacteria from natural sources against intestinal Escherichia coli pathotypes. Electronic Physician, 10(3), 6534–6539.

Khodaii, Z., Ghaderian, S. M. H., & Natanzi, M. M. (2017). Probiotic bacteria and their supernatants protect enterocyte cell lines from enteroinvasive Escherichia coli (EIEC) invasion. International Journal of Molecular and Cellular Medicine, 6(3), 183.

Kiymaci, M. E., Altanlar, N., Gumustas, M., Ozkan, S. A., & Akin, A. (2018). Quorum sensing signals and related virulence inhibition of Pseudomonas aeruginosa by a potential probiotic strain's organic acid. Microbial Pathogenesis, 121, 190–197.

Knysh, O. V. (2019). Bifidogenic properties of cell-free extracts derived from probiotic strains of Bifidobacterium bifidum and Lactobacillus reuteri. Regulatory Mechanisms in Biosystems, 10(1), 124–128.

Knysh, O. V., Isajenko, O. J., Babych, J. M., Poljans'ka, V. P., Zachepylo, S. V., Kompanijec', A. M., & Gorbach, T. V. (2018). Sposib oderzhannja biologichno aktyvnyh deryvativ bakterij probiotychnyh shtamiv [Method for obtaining biologically active derivatives of bacteria of probiotic strains]. Patent of Ukraine for useful model No 122859. Derzhavne Patentne Vidomstvo Ukrainy, Kyiv (in Ukrainian).

Lebeer, S., Vanderleyden, J., & De Keersmaecker, S. C. J. (2008). Genes and molecules of lactobacilli supporting probiotic action. Microbiology and Molecular Biology Reviews, 72(4), 728–764.

Lin, L., & Zhang, J. (2017). Role of intestinal microbiota and metabolites on gut homeostasis and human diseases. BMC Immunology, 18, 1.

Lindquist, J. A., & Mertens, P. R. (2018). Cold shock proteins: from cellular mechanisms to pathophysiology and disease. Cell Communication and Signaling, 16, 1.

Litvak, Y., Byndloss, M. X., Tsolis, R. M., & Bäumler, A. J. (2017). Dysbiotic Proteobacteria expansion: A microbial signature of epithelial dysfunction. Current Opinion in Microbiology, 39, 1–6.

Martinez de la Peña, C. F., Armstrong, G. D., Arenas-Hernández, M. M. P., & Cieza, R. J. (2016). Homeostasis vs. dysbiosis: Role of commensal Escherichia coli in disease. In: Torres, A. G. (Ed.). Escherichia coli in the Americas. Springer, Cham. Pp. 281–299.

Matamouros, S., Hayden, H. S., Hager, K. R., Brittnacher, M. J., Lachance, K., Weiss, E. J., Pope, C. E., Imhaus, A.-F., McNally, C. P., Borenstein, E., Hoffman, L. R., & Miller, S. I. (2018). Adaptation of commensal proliferating Escherichia coli to the intestinal tract of young children with cystic fibrosis. Proceedings of the National Academy of Sciences, 115(7), 1605–1610.

McCarville, J. L., Caminero, A., & Verdu, E. F. (2016). Novel perspectives on therapeutic modulation of the gut microbiota. Therapeutic Advances in Gastroenterology, 9(4), 580–593.

Miquel, S., Lagrafeuille, R., Souweine, B., & Forestier, C. (2016). Anti-biofilm activity as a health issue. Frontiers in Microbiology, 7, 592.

Mokoena, M. P. (2017). Lactic acid bacteria and their bacteriocins: Classification, biosynthesis and applications against uropathogens: A mini-review. Molecules, 22(8), 1255.

Peh, K. K., Pyar, H., & Liong, M.-T. (2011). Inhibitory effect of metabolites from probiotics Lactobacillus acidophilus strains on growth of pathogenic bacteria. Journal of Pharmacology and Toxicology, 6(5), 533–540.

Sarkar, A., & Mandal, S. (2016). Bifidobacteria – insight into clinical outcomes and mechanisms of its probiotic action. Microbiological Research, 192, 159–171.

Scales, B. S., Dickson, R. P., & Huffnagle, G. B. (2016). A tale of two sites: How inflammation can reshape the microbiomes of the gut and lungs. Journal of Leukocyte Biology, 100(5), 943–950.

Sharma, V., Harjai, K., & Shukla, G. (2017). Effect of bacteriocin and exopolysaccharides isolated from probiotic on P. aeruginosa PAO1 biofilm. Folia Microbiologica, 63(2), 181–190.

Shenderov, B. A. (2013). Metabiotics: Novel idea or natural development of probiotic conception. Microbial Ecology in Health and Disease, 24(1), 20399.

Singh, A., Vishwakarma, V., & Singhal, B. (2018). Metabiotics: The functional metabolic signatures of probiotics: Current state-of-art and future research priorities. Metabiotics: Probiotics effector molecules. Advances in Bioscience and Biotechnology, 9(4), 147–189.

Spinler, J. K., Auchtung, J., Brown, A., Boonma, P., Oezguen, N., Ross, C. L., Luna, R. A., Runge, J., Versalovic, J., Peniche, A., Dann, S. M., Britton, R. A., Haaga, A., & Savidge, T. C. (2017). Next-generation probiotics targeting Clostridium difficile through precursor-directed antimicrobial biosynthesis. Infection and Immunity, 85, 10.

Stecher, B. (2015). The roles of inflammation, nutrient availability and the commensal microbiota in enteric pathogen infection. Microbiology Spectrum, 3, 3.

Stepanović, S., Vuković, D., Hola, V., Bonaventura, G. D., Djukić, S., Ćirković, I., & Ruzicka, F. (2007). Quantification of biofilm in microtiter plates: Overview of testing conditions and practical recommendations for assessment of biofilm production by staphylococci. APMIS, 115(8), 891–899.

Tachedjian, G., Aldunate, M., Bradshaw, C. S., & Cone, R. A. (2017). The role of lactic acid production by probiotic Lactobacillus species in vaginal health. Research in Microbiology, 168(9–10), 782–792.

Valdes, A. M., Walter, J., Segal, E., & Spector, T. D. (2018). Role of the gut microbiota in nutrition and health. British Medical Journal, 361, k2179.

Winter, S. E., & Bäumler, A. J. (2014). Dysbiosis in the inflamed intestine: Chance favors the prepared microbe. Gut Microbes, 5(1), 71–73.

Yu, L. C. H. (2018). Microbiota dysbiosis and barrier dysfunction in inflammatory bowel disease and colorectal cancers: Exploring a common ground hypothesis. Journal of Biomedical Science, 25(1), 79.

Ali, M. A. E., Janson, J.-C., & Ali, E. (2012). Antimicrobial potential of Saccharomyces boulardii extracts and fractions. Journal of Applied Sciences Research, 8(8), 4537–4543.

Allonsius, C. N., van den Broek, M. F. L., De Boeck, I., Kiekens, S., Oerlemans, E. F. M., Kenn, F., Vandenheuvel, D., Cos, P., Delputte, P., & Lebeer, S. (2017). Interplay between Lactobacillus rhamnosus GG and Candida and the involvement of exopolysaccharides. Microbial Biotechnology, 10(6), 1753–1763.

Al-Malkey, M. K., Munira, C. I., Abo Al-Hur, F. J., Mohammed, S. W., & Nayyefa, H. J. (2017). Antimicrobial effect of probiotic Lactobacillus spp. on Pseudomonas aeruginosa. Journal of Contemporary Medical Sciences, 3(10), 218–223.

Alokomi, H. L., Skytta, E., Saarela, M., Mattila-Sandholm, T., Latva-Kala, K., & Helander, I. M. (2000). Lactic acid permeabilizes gram-negative bacteria by disrupting the outer membrane. Applied and Environmental Microbiology, 66, 2001–2005.

Ambalam, P. S., Prajapati, J. B., Dave, J. M., Baboo, M. N., Ljungh, Å., & Vyas, B. R. M. (2009). Isolation and characterization of antimicrobial proteins produced by a potential probiotic strain of human Lactobacillus rhamnosus 231 and its effect on selected human pathogens and food spoilage organisms. Microbial Ecology in Health and Disease, 21, 211–220.

Arcilla, M. S., Hattem, J. M., Haverkate, M. R., Bootsma, M. C. J., van Genderen, P. J. J., Goorhuis, A., Grobusch, M. P., Lashof, A. M. O., Molhoek, N., Schultsz, C., Stobberingh, E. E., Verbrugh, H. A., Jong, M. D., Melles, D. C., & Penders, J. (2017). Import and spread of extended-spectrum β-lactamase-producing Enterobacteriaceae by international travellers (COMBAT study): A prospective, multicentre cohort study. Lancet Infectious Diseases, 17(1), 78–85.

Badaoui Najjar, M., Kashtanov, D., & Chikindas, M. L. (2009). Natural Antimicrobials ε-poly-L-lysine and nisin A for control of oral microflora. Probiotics and Antimicrobial Proteins, 1(2), 143.

Bai, A., Weaver, M., Bao, F., Chan, E. D., & Bai, X. (2016). Saccharomyces boulardii produces a factor that inhibits Mycobacterium intracellular burden in human macrophages. Advances in Microbiology, 6(13), 965–974.

Bechinger, B., & Gorr, S. U. (2016). Antimicrobial peptides: Mechanisms of action and resistance. Journal of Dental Research, 96, 3.

Beyer, G., Hiemer-Bau, M., Ziege, S., Edlund, C., Lode, H., & Nord, C. E. (2000). Impact of moxifloxacin versus claritromycin on normal oropharyngeal microflora. European Journal of Clinical Microbiology and Infectious Diseases, 19(7), 548–550.

Brzozowski, B., Bednarski, W., & Gołek, P. (2011). The adhesive capability of two Lactobacillus strains and physicochemical properties of their synthesized biosurfactants. Food Technology and Biotechnology, 49, 177–186.

Buharin, O. V. (1999). Persistencija patogennyh bakterij [Persistence of pathogennic bacteria]. Medicina, Moscow (in Russian).

Daba, H., & Saidi, S. (2015). Detection of bacteriocin-producing lactic acid bacteria from milk in various farms in north-east Algeria by a new procedure. Agronomy Research, 13(4), 907–918.

Dorofeev, J. J., Koljado, E. V., Koljado, V. B., & Beskrovnaja, E. V. (2017). Dinamika smertnosti ot infekcionnyh i parazitarnyh zabolevanij v Altajskom krae [Dynamics of mortality from infectious and parasitic diseases in the Altai Territory]. Medicina v Kuzbasse, 16(4), 91–95 (in Russian).

Ebbensgaard, A., Mordhorst, H., Aarestrup, F. M., & Hansen, E. B. (2018). The role of outer membrane proteins and lipopolysaccharides for the sensitivity of Escherichia coli to antimicrobial peptides. Frontiers in Microbiology, 9, 2153.

El-Halfawy, O. M., & Valvano, M. A. (2013). Chemical communication of antibiotic resistance by a highly resistant subpopulation of bacterial cells. PLoS One, 8(7), e68874.

Forestier, C., Champs, C. D., Vatoux, C., & Joly, B. (2001). Probiotic activities of Lactobacillus casei rhamnosus: In vitro adherence to intestinal cells and antimicrobial properties. Research in Microbiology, 152, 167–173.

Frickmann, H. (2018). Influence of probiotic culture supernatants on in vitro biofilm formation of staphylococci. European Journal of Microbiology and Immunology, 2018, 38.

Gupta, R., & Srivastava, S. (2014). Antifungal effect of antimicrobial peptides (AMPs LR14) derived from Lactobacillus plantarum strain LR/14 and their applications in prevention of grain spoilage. Food Microbiology, 42, 1–7.

Isayenko, O. Y., Knysh, O. V., Babych, Y. M., Ryzhkova, T. N., & Dyukareva, G. I. (2019). Effect of disintegrates and metabolites of Lactobacillus rhamnosus and Saccharomyces boulardii on biofilms of antibiotic resistant conditionally pathogenic and pathogenic bacteria. Regulatory Mechanisms in Biosystems, 10(1), 3–8.

Jakovlev, S. A. (2017). Infekcionnye zabolevanija kak global'naja problema sovremennosti [Infectious diseases as a global problem of our time]. Territorija Nauki, 1, 20–25 (in Russian).

Kaktcham, P. M., Zambou, N. F., Fonteh, A. F., Sieladie, D. V., & Tchouanguep, M. F. (2011). Characterization of bacteriocin produced by Lactobacillus rhamnosus 1K isolated from traditionally fermented milk in the western highlands region of Cameroon. New York Science Journal, 4(8), 121–128.

Kraker, M. E. A., Stewardson, A. J., & Harbarth, S. (2016). Will 10 million people die a year due to antimicrobial resistance by 2050? PLoS Medicine, 13(11), e1002184.

Liévin-Le, M. V., & Servin, A. L. (2014). Anti-infective activities of Lactobacillus strains in the human intestinal microbiota: From probiotics to gastrointestinal anti-infectious biotherapeutic agents. Clinical Microbiology Reviews, 27(2), 167–199.

Lupo, A., Haenni, M., & Madec, J. Y. (2018). Antimicrobial resistance in Acinetobacter spp. and Pseudomonas spp. Microbiology Spectrum, 2018, 6, 3.

Malanovic, N., & Lohner, K. (2016). Gram-positive bacterial cell envelopes: The impact on the activity of antimicrobial peptides. Biochimica et Biophysica Acta, 1858(5), 936–946.

Mančušková, T., Medveďová, A., & Valík, Ľ. (2017). Antimicrobial potential of probiotics in combination with start er lactic acid bacteria. Scientia Agriculturae Bohemica, 48(4), 208–215.

Mirnejad, R., Vahdati, A. R., Rashidiani, J., Erfani, M., & Piranfar, V. (2013). The antimicrobial effect of Lactobacillus casei culture supernatant against multiple drug resistant clinical isolates of Shigella sonnei and Shigella flexneri in vitro. Iranian Red Crescent Medical Journal, 15(2), 122–126.

Mitsakakis, K., Kaman, W. E., Elshout, G., Specht, M., & Hays, J. P. (2018). Challenges in identifying antibiotic resistance targets for point-of-care diagnostics in general practice. Future Microbiology. 13(10), 1157–1164.

Nes, I. F., & Holo, H. (2000). Class II antimicrobial peptides from lactic acid bacteria. Biopolymers, 55(1), 50–61.

Nikaido, H. (2011). Structure and mechanism of RND-type multidrug efflux pumps. Enzymology and Related Areas of Molecular Biology, 77, 1–60.

Nomoto, K. (2005). Prevention of infections by probiotics. Journal of Bioscience and Bioengineering, 100(6), 583–592.

Oliveira, L. C., Silveira, A. M. M., Monteiro, A. S., Dos Santos, V. L., Nicoli, J. R., Azevedo, V. A. C., Soares, S. C., Dias-Souza, M. V., & Nardi R. M. D. (2017). In silico prediction, in vitro antibacterial spectrum, and physicochemical properties of a putative bacteriocin produced by Lactobacillus rhamnosus Strain L156.4. Frontiers in Microbiology, 8, 876.

Östholm, B. Å., Tärnberg, M., Nilsson, M., Nilsson, L. E., Hanberger, H., Hällgren, A., & Southeast Sweden Travel Study Group (2018). Duration of travel-associated faecal colonisation with ESBL-producing Enterobacteriaceae – A one year follow-up study. PLoS One, 13(10), e0205504.

Ponomarev, S. I., & Jakovlev, S. A. (2017). Infekcionnye zabolevanija kak mediko-socialnaja problema [Infectious diseases as a medical and social problem]. Sinergija, 1, 110–119 (in Russian).

Portella, A. C. F., Karp, S., Scheidt, G. N., Woiciechwski, A. L., Parada, J. L., & Soccol, C. R. (2009). Modelling antagonic effect of lactic acid bacteria supernatants on some pathogenic bacteria. Brazilian Archives of Biology and Technology, 52, 29–36.

Ramsamy, Y., Essack, S. Y., Sartorius, B., Patel, M., & Mlisana, K. P. (2018). Antibiotic resistance trends of ESKAPE pathogens in Kwazulu-Natal, South Africa: A five-year retrospective analysis. African Journal of Laboratory Medicine, 7(2), 887.

Richter, M. F., & Hergenrother, P. J. (2019). The challenge of converting Gram-positive-only compounds into broad-spectrum antibiotics. Annals of the New York Academy of Sciences, 1435(1), 18–38.

Sahib, F. H., Aldujaili, N. H., & Alrufae, M. M. (2017). Biosynthesis of silver nanoparticles using Saccharomyces boulardii and study their biological activities. European Journal of Pharmaceutical and Medical Research, 4(9), 65–74.

Sambanthamoorthy, K., Feng, X., Patel, R., Patel, S., & Paranavitana, C. (2014). Antimicrobial and antibiofilm potential of biosurfactants isolated from lactobacilli against multi-drug-resistant pathogens. BMC Microbiology, 14, 197.

Santajit, S., & Indrawattana, N. (2016). Mechanisms of antimicrobial resistance in ESKAPE pathogens. Biomed Research International, 2016, 2475067.

Sarika, A. R., Lipton, A. P., & Aishwarya, M. S. (2010). Bacteriocin production by a new isolate of Lactobacillus rhamnosus GP1 under different culture conditions. Food Science and Technology, 2(5), 291–297.

Stefania, D. M., Miranda, P., Diana, M., Claudia, Z., & Rita, P. (2017). Antibiofilm and antiadhesive activities of different synbiotics. Journal of Probiotics and Health, 5, 182.

Stier, H., & Bischoff, S. (2016). Influence of Saccharomyces boulardii CNCM I-745 on the gut-associated immune system. Clinical and Experimental Gastroenterology, 9, 269–279.

Tsutsui, А., & Suzuki, S. (2018). Japan nosocomial infections surveillance (JANIS): A model of sustainable national antimicrobial resistance surveillance based on hospital diagnostic microbiology laboratories. BMC Health Services Research, 18, 799.

Ursova, N. I. (2013). Aktualnye problemy i nereshennye problemy probiotikoterapii [Relevant problems and unsolved problems of probiotic therapy]. Lechashhij Vrach, 8, 60–65 (in Russian).

Wald, E. R. (2011). Acute otitis media and acute bacterial sinusitis. Clinical Infectious Diseases, 52(4), 277–283.

Wang, Z., Shen, Y., & Haapasalo, M. (2017). Antibiofilm peptides against oral biofilms. Journal of Oral Microbiology, 9(1), 1327308.

Published
2019-04-17
How to Cite
Knysh, O. V., Isayenko, O. Y., Voyda, Y. V., Kizimenko, O. O., & Babych, Y. M. (2019). Influence of cell-free extracts of Bifidobacterium bifidum and Lactobacillus reuteri on proliferation and biofilm formation by Escherichia coli and Pseudomonas aeruginosa . Regulatory Mechanisms in Biosystems, 10(2), 251-256. https://doi.org/10.15421/021938