Fresh petals of each species were extracted using 5% HCOOH in MeOH. After removing solvents by evaporation, each extract was applied to column chromatography using Diaion HP-20SS (Mitsubishi Chemical Co., Japan) and eluted with 0.5% TFA (trifluoroacetic acid), 10% MeCN containing 0.5% TFA and 25% MeCN containing 0.5% TFA. The fractions were chromatographed on a Sephadex LH-20 gel, eluenting with MeOH/H 2 O/HCOOH (70:25:5). The mixtures were applied to preparative HPLC using a Shimadzu HPLC system equipped with an Inertsil ODS-4 column (I.D. 10 × 250 mm, GL Sciences Inc., Japan) under the following conditions. The eluent was 10% MeCN containing 5% HCOOH to 20% MeCN containing 5% HCOOH at a flow rate of 3 -3.5 mL min -1 .
Three anthocyanins (1-3), four flavonols (4-7), and three flavones (8-10) were isolated from P. coerulea var. The MS was performed on a Shimadzu LC/MS system using an Inertsil ODS-4 column (I.D. 10×250 mm, GL Sciences Inc., Tokyo) equipped with a PDA detector (4.5 kV for ESI + and 3.5 kV for ESI -; interface temperature as 250°C).
NMR spectroscopy was recorded on a Bruker AVANCE III HD 800 spectrometer equipped with a 5-mm TCI cryogenic probe and Z-axis gradient (Bruker Biospin AG, Switzerland). All spectra were obtained in 0.
Three anthocyanins (1-3), four flavonols (4-7), and three flavones (8-10) were isolated from P. coerulea var. The MS was performed on a Shimadzu LC/MS system using an Inertsil ODS-4 column (I.D. 10×250 mm, GL Sciences Inc., Tokyo) equipped with a PDA detector (4.5 kV for ESI + and 3.5 kV for ESI -; interface temperature as 250°C).
NMR spectroscopy was recorded on a Bruker AVANCE III HD 800 spectrometer equipped with a 5-mm TCI cryogenic probe and Z-axis gradient (Bruker Biospin AG, Switzerland). All spectra were obtained in 0.