Green Tea Characterization of Material Experiment CSV JSON

Characterization of Material Study


Quantities are reported as mass of consistent per mass of green tea leaves.

Sample Compound measured Value Measurement Study sequence Additional information N replicates

Experimental Conditions

Material Preparation

200 mg

20 mL


20 mL


For product extraction, 200 mg of sample and 20 mL methanol were added to a 20 mL scintillation vial. Mixtures were shaken overnight at room temperature, filtered, and dried under reduced pressure and stored at -80°C until analysis.

NMR Analysis

JEOL ECA-400 spectrometer

<sup>1</sup>H (proton)

400 MHz

Methanol-d<sub>4</sub> (CD<sub>3</sub>OD)

10 mg/mL

Each sample was resuspended in CD3OD to a concentration of 10 mg/mL. NMR spectra were acquired with a JEOL ECA-400 spectrometer equipped with a high-sensitivity JEOL Royal probe and a 24-slot autosampler. NMR chemical shift values were referenced to residual solvent signals for CD3OD (δH 3.31 ppm).

Mass Spectrometry Analysis

Q Exactive Plus quadrupole-orbitrap mass spectrometer

1 mg/mL

Full scan, high resolution

Electrospray ionization (ESI)

Positive/Negative switching

Waters Acquity UPLC

Water:Acetonitrile (A:B)

95:5 (A:B) for 1 min, then gradient to 0:100 over 20 minutes, holding for 1 min at 0:100

0.3 mL/min

Waters Acquity UPLC BEH C18 1.7 μm, 2.1 × 50 mm

The mass spectrometer was operated in the positive/negative switching ionization mode over a full scan range of m/z 150-2000 with the following settings: capillary voltage, 5 V; capillary temperature, 300 °C; tube lens offset, 35 V; spray voltage, 3.80 kV; sheath gas flow 35 and auxiliary gas flow 20.

Metabolite Quantification




0.1-200 µg/mL



Quantification of the major catechin, phenolic acid, and flavonoid components of the green tea products used 15 calibration standards. LC-MS analysis was conducted as described. Standards were prepared in spectrometric-grade MeOH and diluted in a two-fold dilution series ranging from 0.1-200 μg/mL before injection. A calibration curve was constructed by plotting the area of the selected ion chromatogram for each standard versus nominal concentration. Concentrations of each standard in the extracts were determined by 1/x2 weighted least-squares linear regression.