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

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.

The promises and risks of probiotic Bacillus species.

Supplementing the human microbiome with probiotic microorganisms is a proposed solution for civilization syndromes such as dysbiosis and gastrointestinal tract (GIT) disorders. Bimodal probiotic strains of the Bacillus genus constitute the microbiota of the human environment, and are typically found in soil, water, a number of non-dairy fermented foods, as well as in human and animal GIT. Probiotic Bacillus sp. are Gram positive rods, with the ability of sporulation to survive environmental stress and preparation conditions. In vitro models of the human stomach and human studies with probiotic Bacillus reveal the mechanisms of its life cycle and sporulation. The Bacillus sp. probiotic biofilm introduces biochemical effects such as antimicrobial and enzymatic activity, thus contributing to protection from GIT and other infections. Despite the beneficial activity of Bacillus strains belonging to the safety group 1, a number of strains can pose a substantial health risk, carrying genes for various toxins or antibiotic resistance. Commercially available Bacillus probiotic preparations include strains from the subtilis and other closely related phylogenetic clades. Those intended for oral administration in humans, often encapsulated with appropriate supporting materials, still tend to be mislabeled or poorly characterized. Bacillus sp. MALDI-TOF analysis, combined with sequencing of characteristic 16S rRNA or enzyme coding genes, may provide accurate identification. A promising future application of the probiotic Bacillus sp. might be the microflora biocontrol in the human body and the closest human environment. Environmental probiotic Bacillus species display the potential to support human microflora, however controversies regarding the safety of certain strains is a key factor in their still limited application.