Probiotic bacteria exhibiting antagonistic activities against pathogenic bacteria are widely considered as potential options for the prevention and treatment of various infectious diseases and represent potential substitutes of antibiotics. Here we show that the L. plantarum AG10 strain represses the growth of Staphylococcus aureus and Escherichia coli in vitro and diminishes their negative effects in vivo in a Drosophila melanogaster model of survival on embryonic (larvae) and pupa stages. In an agar drop diffusion test, L. plantarum AG10 exhibited antagonistic properties against Escherichia coli, Staphylococcus aureus, Serratia marcescens and Pseudomonas aeruginosa, and repressed the growth of E. coli and S. aureus during milk fermentation. In a Drosophila melanogaster model, L. plantarum AG10 alone did not provide any significant effect, either during the embryonic stage or during further development of the flies. Despite this, it was able to restore the viability of groups infected with either E. coli and S. aureus, almost to the level of non-treated control at all stages of development (larvae, pupa and adult). Moreover, in the presence of L. plantarum AG10, pathogens-induced mutation rates and recombination events reduced 1.5–2-fold. The genome of L. plantarum AG10 was sequenced and deposited at NCBI under the accession number PRJNA953814 and consists of annotated genome and raw sequence data. It consists of 109 contigs and is 3,479,919 bp in length with a GC content of 44.5%. The analysis of the genome has revealed considerably few putative virulence factors and three genes responsible for the biosynthesis of putative antimicrobial peptides, with one of them exhibiting a high probability of antimicrobial properties. Taken together, these data allow the suggestion that the L. plantarum AG10 strain is promising for use in both dairy production and probiotics as a preservative from foodborne infections.
Currently, in the diagnosis of diseases, a decisive place is given to laboratory methods, which should be informative, relatively simple to perform and rapid. The article describes the approbation of a method for rapid detection of Escherichia coli and bacteria of Escherichia coli group in the oral cavity. Research involved 44 volunteers, who were sampled from the oral cavity, followed by incubation in Koda’s medium. The study used oral (n=11) and gingival fluids (n=11); smears-prints from the oral mucosa (n=11); dental biofilm (n=11). After 24 hours, the change in color and transparency of the medium was assessed. The preservation of the initial green color and transparency by the medium meant the absence of E. coli and bacteria of Escherichia coli group in the sample. A change in the color of the medium to yellow, turbidity and / or the formation of bubbles indicated the presence of E. coli and bacteria of Escherichia coli group. In parallel, the material was inoculated onto Endo agar, followed by identification of strains to species. As a result of the study, a complete coincidence of the results of the classical bacteriological method and the method using Koda medium was shown. In the latter case, a significant advantage is the speed of obtaining the result (18-20 hours), in contrast to the classical method, the interpretation of the results of which is available only after 72 hours or more. All of this is in line with the state of the art in clinical microbiology and rapid diagnosis based on «point-of-care testing / doctor’s office» diagnostic principle. The presented method can be successfully applied in clinical practice for topical diagnosis of microorganisms E. coli and bacteria of Escherichia coli group in the oral cavity.
It is known that the concentration of alpha-amylase in saliva can determine its catalytic activity, the decrease of which occurs during various pathological processes in the oral cavity. The overwhelming number of methods for determining the catalytic activity of enzymes involve the use of a large volume of reagents and samples, which makes it difficult to study saliva in large groups. The purpose of the study is to evaluate the possibility of using the microvariation of the reaction to determine the activity of saliva alpha-amylase, as well as to analyze the dependence of the enzyme activity on its concentration. Materials and methods. Saliva was obtained from 15 people with intact periodontal disease and the dentition, without somatic pathology. For in vitro studies, alpha-amylase solutions were prepared with an enzyme concentration of 10; five; 2.5; one; 0.5 and 0.25 mg / ml ex tempore. To save samples and reagents, the volume of the reaction participants was proportionally reduced. The further analysis procedure was carried out according to the instructions of the manufacturer of the «AMYLASE-VITAL» reagent kit to determine the activity of alpha-amylase. Statistical analysis of the results was performed using the Student’s t-test in the program Statistica 7.0. Results. The comparability of the results of determining the activity of alpha-amylase using the classical and microplate variants of the reaction is shown. With an increase in alpha-amylase concentration from 0 to 2.5 mg / ml, a directly proportional increase in enzyme activity is observed. In the case of an increase in the concentration of alpha-amylase above 2.5 mg / ml, a decrease in its activity is shown, which may be due to the precipitation of a part of the enzyme. The activity of the enzyme in saliva of practically healthy individuals using the microvariation of the reaction was 528.6 ± 2.4 U / l. In conclusion the use of a microvariant of the reaction for determining the activity of alpha-amylase may be justified for a large number of subjects. A linear dependence of the enzyme activity on its concentration in the range of 0-2.5 mg / ml is shown.
The paper deals with historical information on the formation and development of the Department of Therapeutic Stomatology of Academician Ye. A Vagner Perm State Medical University – “Alma-mater” for several generations of dentists. It is the history not only in figures and factors but regards people, who contributed to the development of native stomatology in the Ural region.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.