Nanodrop lite plus spectrophotometer

The extraction of the genomic DNA of L. monocytogenes F2365 was carried out using a QIAamp^® DNA Mini Kit (QIAGEN Sciences, Germantown, MD, USA). The ratio of OD₂₆₀/OD₂₈₀ (1.8 ≤ OD₂₆₀/OD₂₈₀ ≤ 2.0) and optical density at 260 nm (OD₂₆₀), respectively, was measured with the aid of a NanoDrop Lite Plus Spectrophotometer (Thermo Fisher Scientific, Wilmington, DE, USA). The genomic DNA was diluted with 10 mM of a Tris-HCl buffer (pH 7.2) to obtain a final DNA concentration of 40 µg/mL. Additionally, the COS-EGCG conjugate was diluted with the same buffer to gain the various concentrations (0, MIC, 2 × MIC, and 4 × MIC). The treated DNA with the COS-EGCG conjugate at various concentrations and untreated DNA were measured on 0.8% agarose gel [23 (link)]. The quantitative measurement of DNA bands was done using ImageJ software and calculated as the percentage of band intensity, compared with the band of untreated DNA.

Samples were collected for clinical testing. DNA was extracted using QIAamp DNA Blood Mini Kit (Qiagen, Germantown, Maryland) following the manufacturer's instructions. RNA was extracted using NucleoSpin RNA Blood Midi Kit (Takara Bio Inc, Shiga, Japan), following the manufacturer's instructions. Nucleic acid was quantified using NanoDrop Lite Plus Spectrophotometer (Thermo Fisher Scientific Inc.)