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Promoting general health in terms of obesity and diabetes prevention is recommended by health care systems. The objectives of this study were to isolate an efficient glucose-converting Komagataeibacter xylinus to cellulose and to evaluate the safety of the selected strain as a new generation of probiotics in the fight against obesity. Of the 97 samples, 43 K xylinus strains were isolated and evaluated for their glucose conversion rate and 5 strains were examined for probiotic activities by in vitro assays. A strain with significant performance was fed to rats in order to determine its safety status in vivo. The results revealed that the strain K.X.1 had high level of glucose conversion rate and significant survival rate in acidic pH and bile salt. No adverse clinical signs and bacterial translocation to rats’ organs were observed. The results showed that the strain of K. xylinus K.X.1 has suitable probiotic properties.

Background and Objectives: Acetic acid bacteria (AAB) are one of the major interests of researchers. Traditional vinegars are suitable sources of AAB because they are not undergone industrial process like filtering and adding preservatives. Komagataeibacter xylinus as a member of AAB is known as the main cellulose producer among other bacteria. The purpose of the current study was to isolate the bacteria from traditional vinegars and its molecular analyses. Materials and Methods: Vinegar samples were collected. Well-organized bacteriological tests were carried out to differentiate isolated bacteria from other cellulose producers and to identify K. xylinus. NaOH treatment and Calcofluor white staining were used for detecting cellulose. Chromosomal DNA of each strain was extracted via three methods of boiling, phenol-chloroform and sonication. Molecular analyses were performed on the basis of 16S rRNA sequences and cellulose synthase catalytic subunit gene (bcsA) for further confirmation. Phylogenetic tree was constructed for more characterization. Two housekeeping genes were studied including phenylalanyl-tRNA synthase alpha subunit (pheS) and RNA polymerase alpha subunit (rpoA). Results: Of the 97 samples, 43 K. xylinus strains were isolated. They were identified via bacteriological and molecular techniques. 16S rDNA sequence showed 99% similarity with registered sequences of the bacteria. Biodiversity of the genome confirmed by analyzing bcsA, pheS and rpoA genes. Conclusion: K. xylinus can be isolated from traditional vinegars. Screening tests ought to include the classical methods and molecular techniques. Different molecular techniques and more genomic research should be developed to expand our knowledge for distinguishing isolated bacteria especially in the fields of AAB.