Figure 1. Result of HPLC using trans-cinnamaldehyde as internal control. The mobile phase consisted of a linear gradient of 0.1 % phosphoric acid in water and acetonitrile. The flow rate of the mobile phase was 1.0 ml/min. The injection volume of standard (A) and sample solutions (B) was 10 μL. The UV/Vis spectra were recorded at 265 nm. The peak areas of the samples were correlated with the concentrations according to the standard calibration curve.
