Identification of bacterial species in probiotic consortiums in selected commercial cleaning preparations

Abstract

The role of environmentally coexisting microflora that often comprises human commensal microbiome is still underestimated. Modern lifestyle changes include hygienic practices, food preparation and eradication of many contagious diseases. In this context, probiotic microorganisms are biocontrol remedies still under development, solving a number of gastrointestinal and immunological issues, while fighting hazardous microbiological biofilms on different surfaces. Probiotics are mainly associated with Lactic Acid Bacteria, however environmental, non-dairy sources are promising ecological niches of probiotic spore-forming Bacillus species. Industrial applications of these “unconventional” probiotics take an advantage of their sporulating activity which greatly enhances their compatibility with chemical formulations used in the household, cosmetic or pharmaceutical chemistry. We have analysed 14 commercially available chemical products, labelled or described to contain a probiotic or biologically active component. It was determined that in the most part they relay on consortiums of spore-forming, very closely related Bacillus species, exhibiting bimodal existence in the environment and the gastrointestinal tract (GIT). In addition, we have found a number of non-sporulating species. Overall, the microorganisms found included: Bacillus licheniformis, Bacillus subtilis, Bacillus pumilus, Citrobacter freundii, Klebsiella oxytoca, Stenotrophomonas malthophila, Serratia liquefaciens, Bacillus altitudinis, Lactobacillus gastricus, Bacillus megaterium, Lactobacillus nagelii, Aromatoleum buckelii, Trichosporon mucoides, Clostridium novyi, Bacteroides uniformis. As some of the listed species may become opportunistic pathogens, this raises an important question concerning general safety of probiotics, as apparently the manufacturing procedures do not always lead to microbiologically defined or sufficiently controlled microorganism consortiums.