Twenty Korean barley cultivars (Geongang, Gwangan, Nackyoung, Dahyang, Daejin, Saegang, Boanchal, Keunal, Saessal, Saechalssal, Sujung, and Boanchalssal) were selected in this research. All the cultivars were developed by the National Institute of Crop Science (NICS), Rural Development Administration (RDA), Korea and were grown during 2013 in the experimental fields of the NICS, Milyang, Gyeongnam. After harvesting, barley leaves were immediately washed with clean sterile water and then air-dried for 2 days at room temperature. The collected leaves (Fig. 1) were freeze-dried immediately after sampling (harvest dates:30th March, 10th April, 28th April, and 12th May, 2013) and stored at –40 ºC prior to analysis.
[Insert Figure 1]
Analytical grade water, acetonitrile, and TFA were purchased for UPLC analysis from J.T. Baker (Phillipsburg, NJ, USA). For quantitative analysis, phenolic compounds used for the standards were isolated from barley leaves, as reported in earlier method (Park et al., 2014). DPPH, ABTS, BHT, Trolox, and potassium persulphate, Sephadex LH-20, acetic acid, formic acid, and DMSO-d6 were obtained from …show more content…
The pulverized sample (1.0 g, 60 mesh) was extracted with 20 mL of the 80% methanol for 24 h in a shaking incubator at 25 °C. The crude extract was filtered through a PTEE syringe filter before UPLC analysis. for the calibration curve, the peak area of the isolated phenolic compounds was integrated with the UPLC chromatogram at 335 nm and plotted against the concentration to create a linear curve. The stock solution was prepared in MeOH to obtain a 1 mg/mL concentration. Ten curves were obtained by diluting the individual stock solutions in MeOH to six different concentrations including 0.5, 1, 2.5, 5, 50, and 100 μg/mL. The correlation coefficients (r2) of each curve were observed higher than
[Insert Figure 1]
Analytical grade water, acetonitrile, and TFA were purchased for UPLC analysis from J.T. Baker (Phillipsburg, NJ, USA). For quantitative analysis, phenolic compounds used for the standards were isolated from barley leaves, as reported in earlier method (Park et al., 2014). DPPH, ABTS, BHT, Trolox, and potassium persulphate, Sephadex LH-20, acetic acid, formic acid, and DMSO-d6 were obtained from …show more content…
The pulverized sample (1.0 g, 60 mesh) was extracted with 20 mL of the 80% methanol for 24 h in a shaking incubator at 25 °C. The crude extract was filtered through a PTEE syringe filter before UPLC analysis. for the calibration curve, the peak area of the isolated phenolic compounds was integrated with the UPLC chromatogram at 335 nm and plotted against the concentration to create a linear curve. The stock solution was prepared in MeOH to obtain a 1 mg/mL concentration. Ten curves were obtained by diluting the individual stock solutions in MeOH to six different concentrations including 0.5, 1, 2.5, 5, 50, and 100 μg/mL. The correlation coefficients (r2) of each curve were observed higher than