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The primary purpose of these researches was to optimize single-cell protein (SCP) production process using Saccharomyces cerevisiae NCAIM Y.00200 and Kluyveromyces marxianus DSM 4908 strain, and then to analyse the changes in yield of single-cell protein final product using vitamin supplementation. To determine these values, the total sugar content of the fermentation medium, and the protein content of the yeast was determined. During our work, a particular attention was paid to the change of sugar content and yeast protein quantity. Besides, yield (Yx/s) values, typical of the whole fermentation, were also measured. Protein yield, as the final product of fermentation, featured the efficiency of our work. The results of our optimized trial settings that were considered as control, using S. cerevisiae NCAIM Y.00200 and K. marxianus DSM 4908 strains, were compared with the results of vitamin-supplemented fermentation processes. On this basis, we can say that during our trials vitamin supplementation did not influence the final product yield of processes. The counted protein yields during fermentation were between 0.4–0.7 g g−1.

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Six strains (Bi11, Bi30, Bi36, Bi50, Bi52 and Bi55) isolated from bio-yoghurts and two strains (KD10 and KD11) derived from human faeces were identified by genus- and species specific polymerase chain reaction (PCR) with reference to the type strains of B. animalis subsp. lactis DSM 10140 and B. animalis subsp. animalis DSM 20104. The isolates were differentiated by using Bcu I ( Spe I), Xba I and Dra I endonucleases for subsequent pulsed field gel electrophoresis (PFGE) technique and by API 50 CHL tests.All the isolates tested were classified to B. animalis subsp. lactis species. The reliable identification as B. animalis subsp. lactis (by PCR with Bflact2/Bflact5 primers), however, required confirmation by a negative result of B. animalis subsp. animalis -specific PCR.Differentiation of the B. animalis subsp. lactis isolates with PFGE method enabled to distinguish KD11 strain with all the restriction enzymes applied, and Bi11 and Bi30 — exclusively with Dra I and Spe I enzymes, respectively. The biochemical tests, however, revealed that all the strains tested were characterised by a unique fermentation pattern. It was concluded that differentiation of the B. animalis subsp. lactis strains should be carried out on the basis of both genetic and phenotypic features.

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Adhesion of Lactobacillus casei subsp. pseudoplantarum 2750, Lactobacillus sakei DSM 20017 and Bifidobacterium bifidum B3.2 to Caco-2 cell line was investigated in vitro. The adhesion ability of the tested strains was quantified with three methods: fluorescent-labelling, Gram-staining — followed by cell counting and image analysis — and plate count enumeration in order to compare the different detection methods. Results were in good correlation in terms of number of adhered bacteria, however, aggregate formation resulted in a significantly lower result with plate count enumeration in case of L. casei subsp. pseudoplantarum 2750. Percent coverage was found to be an appropriate method to compare adhesion ability of the strains, provided the cell sizes are similar. Gram-staining gives satisfactory results, however, fluorescent staining was not a suitable method in this study, since fluorescent dye hexidium iodide also labelled the intestinal cells.

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The aim of this study was to adapt MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] colorimetric assay (MCA) (Wang et al., 2010) for determination of lactic acid bacteria cell count. Our study is helpful in developing protocols for measuring the viability of other lactic acid bacteria. We determined the cell concentration range which gives linear regression of CFU (colony forming units) and formazan production. In our experiment three authentic lactic acid bacteria strains were investigated: Lactobacillus rhamnosus VT1, L. plantarum 2142, and L. sakei DSM 2001. As data show beside the strain also the growth medium has influence on the MTT reduction activity, this means that for each special case separate calibration curve has to be prepared. Based on MTT reduction we also developed an improved microtiter plate assay which proved to be reliable for a rapid cell count determination. So our methods are only applicable for estimate cell number with fixed parameters, but under given circumstances they are fast and sensitive methods. With the modified methods we can rapidly measure the dehydrogenase enzyme activity of the lactic acid bacteria cells. With the microplate assay we can measure many conditions and strains at the same time.

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372 378 Leder, S., Hartmeier, W. & Marx, S. P. (1999): α-Galactosidase of Bifidobacterium adolescentis DSM 20083. Curr. Microbiol. , 38 , 101

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visited 1 March 2018). [15] LIDAR Composite DSM -1m, https://data.gov.uk/dataset/lidar-composite-dsm-1m1, (last visited 1 March 2018). [16] Opengeodata, https

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] Khan A. R. , Mahmood , A. , Safdar , A. , Khan , Z. A. , Khan N. A. Load forecasting, dynamic pricing and DSM in smart grid: a review , Renewable and Sustainable Energy Reviews , Vol. 54 , 2016 , pp

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DSM 7T and FZB42T: a proposal for Bacillus amyloliquefaciens subsp. amyloliquefaciens subsp. nov. and Bacillus amyloliquefaciens subsp. plantarum subsp. nov. based on complete genome sequence comparisons . Int. J. Syst. Evol. Micr. , 61 , 1786

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. González-Vara , Y.R.A. , Vaccari , G. , Dosi E , Trilli , A. , Rossi , M. & Matteuzzi , D. ( 2000 ): Enhanced production of L-(+)-lactic acid in chemostat by Lactobacillus casei DSM 20011 using ion-exchange resins and cross

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.039 1 t330 seg , sei Vegetables SA-46 Fresh salad mix 2.525 1 t330 - SA-27 Carrot paste 2.421 1 t091 selp * 1: S. aureus subsp. aureus DSM 799; 2: S. aureus subsp. aureus DSM 20231T; 3: S. aureus ATCC 33862 THL. Based on the presence of the

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