Characterization of functional properties of Enteroccoccus feacium strains isolated from human gut

The aim of this work was to characterize the functional properties of Enterococcus faecium strains identified after isolation from human faeces. Of these isolates strain R13 showed the best resistance to low pH, bile salts and survival in the simulated in vitro digestion assay and demonstrated an important level of adhesion to hexadecane as a potential probiotic candidate. Analysis of the antibiotic resistance of E. faecium strains indicated that in general these isolates were sensitive to the tested antibiotics and no strain appeared to be resistant to vancomycin. Examination of the virulence determinants for E. faecium strains demonstrated that all strains contained the virulence genes common in gut and food originated enterococci and strain R13 harboured the lowest number of virulence genes. Additionally no strain contained the genes related with the cytolysin metabolism and showed hemolytic activity. The antimicrobial role of E. faecium strains were tested against several pathogens in which different levels of inhibitory effects were observed and strain R13 was inhibitory to all tested pathogens. The PCR screening of genes encoding enterocin A and B indicated the presence of these genes in E. faecium strains. Preliminary characterization of bacteriocins revealed that their activity was lost after proteolytic enzyme treatments but no alteration in antimicrobial activity was observed at different pHs (3.5 to 9.5) and after heat treatments. In conclusion this study revealed the functional characteristics of E. faecium R13 as a gut isolate and this strain could be developed as a new probiotic after further tests.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Characterization of Bee Bread Produced with Defined Starter Cultures Mimicking the Natural Fermentation Process

Bee bread is a product with unique properties for humans and bees that is produced through the fermentation of pollen in the honeycomb, mainly caused by lactic acid bacteria (LAB) and yeast strains present in the environment. It is a rich source of nutrients such as proteins, polyphenols and vitamins. Despite the potential nutritional value of bee bread, it is consumed at low levels, as harvesting bee bread from the hives is costly and difficult. This study aimed to produce a standard bee bread by using different strains of the fructophilic lactic acid bacteria (FLAB) Lactobacillus kunkeei and the yeasts Starmeralla magnolia MP-2 and Zygosaccharomyces siamensis MP-14, previously isolated from bee products. In this context, bee bread was produced from pollen by solid-state fermentation using selected FLAB and yeast species, which were then compared with spontaneously developed and commercially available bee bread in terms of microbial stability, physicochemical properties, total phenolic component amounts, in vitro digestibility and amino acid profiles. As a result, it was determined that bee bread made from bee pollen fermented with starter cultures showed improved characteristics than commercial bee bread and was more advantageous in terms of absorption as well as production processes

TAM SAYILI PROGRAMLAMA MODELİ İLE OTOBÜS ÇİZELGELEME OPTİMİZASYONU VE UYGULAMASI

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