The MTT method is a quantitative colorimetric toxicity

test, based Savolitinib on the transformation of yellow, soluble tetrazolium salts (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) to purple-blue insoluble formazane. This process occurs naturally in mitochondria of living cells. After 48 h incubation with compounds, cell cultures were supplemented with 10 μl of 5 mg ml−1 MTT solution per well, and further incubated for 4 h at 37 °C. Afterwards, 100 μl of water solution, including 50 % dimethylformamide and 20 % SDS, per well was added and after the all-night incubation the absorbance was measured by the 96-well plastic plate reader (Organon Teknika) at wavelengths of λ = 540 and 620 nm. The medium with

DMSO at tested concentration range without the tested compound served as control––it was not toxic to vero cells line. The experiments were carried out in duplicates. Open AccessThis article is distributed under the terms of the Creative Commons Attribution License which this website permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited. References Agrawal GS-9973 concentration A, Murphy TF (2011) Haemophilus influenzae infections in the H. influenzae type b conjugate vaccine era. J Clin Microbiol 49:3728–3732PubMedCentralPubMedCrossRef Amer FAA, El-Behedy EM, Mohtady HA (2008) New targets for antibacterial agents. Biol Rev Camb Philos Soc 3:46–57 Armbruster CE, Hong W, Pang B, Dew KE, Juneau RA, Byrd MS, Love CF, Kock ND, Swords EW (2009) LuxS promotes biofilm maturation and persistence of nontypeable Haemophilus influenzae in vivo via modulation of

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