The species identification was conducted using standardized ident

The species identification was conducted using standardized identification system API 20E (bioMérieux Italia);   3) Enterococcus spp.: 250 mL of each sample was filtered through a 0,45 μm cellulose membrane filter, placed on Slanetz-Bartley agar (bioMérieux Italia), and Staurosporine purchase plates were incubated at 37°C for 48 hours. If typical colonies (red/brown/pink) were present, the membrane was transferred on pre-warmed (44°C) plates of Bile Aesculina Azide agar (bioMérieux Italia) and incubated at 44°C for 2 hours

(ISO 7899-2). Typical brown/black colonies were identified as Enterococcus spp. using standardized identification system API BAY 11-7082 chemical structure 20 Strep (bioMérieux Italia);   4) Pseudomonas spp.: 250 mL of each sample was filtered through a 0,45 μm cellulose membrane filter, placed on Pseudomonas CN agar (Cetrimide-Nalidixic Acid, bioMérieux Italia), and plates were incubated

at 37°C for 48 hours, blue/green colonies were isolated on Plate Count agar (bioMérieux Italia) at 37°C for 24 hours, and after the oxydase test (bioMérieux Italia), the species identification was conducted using standardized identification system API 20NE (bioMérieux Italia) (prEN ISO 12780);   5) Other microorganisms: singles colonies growing on Tergitol 7 TTC agar (bioMérieux Italia) were transferred on McConkey agar (bioMérieux Italia), and plates were incubated at 37°C for 3-oxoacyl-(acyl-carrier-protein) reductase 24-48 hours; after the oxydase test (bioMérieux Italia), the species identification was conducted using standardized identification systems API 20E/20NE (bioMérieux Italia).   Chemical analyses pH The Ulixertinib mouse pH was determined electrometrically by using the technique recommended in the Standard Methods [13]. Residual free chlorine The residual free chlorine content was measured using the N,N-diethyl-p-phenylenediamine (DPD) colorimetric method at the time of sample collection (colorimetric DPD method; Microquant; Merck, Darmstadt, Germany) [13]. Ammonium For ammonium ions determination,

50 mL of the water sample and the calibration samples were mixed with 1 mL of a potassium tetraiodiomercurate solution. After 20 minutes reaction time at room temperature in NH3-free atmosphere, the solution was examined photometrically at a wavelength of 420 nm in cuvettes of appropriate path length (IRSA-CNR, Rome, Italy). Nitrite For nitrite ion determination, 50 mL of the water sample and the calibration samples were mixed with 2 mL of a freshly prepared mixture of equal parts of sulphanilic acid solution and 1-naphthylamine solution. After 2 hours at 20°C in darkness the extinction at 530 nm was measured [14]. Statistical analysis Basic descriptive summaries were used to describe measures of central tendencies and dispersion of water characteristics and microbial concentrations.

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