Figure 4. HPLC chromatograms of crude water extract of FDB in acid (A), alkaline (B) hydrolysis and standard solution mixture (C). (D) UV-spectra of peak 3 and 4 corresponding to p-coumaric acid and vitexin.

These compounds were detected at a total run of 9 min by using two different wavelength at 280 and 335 nm. Standard solution mixture consists of gallic acid (1), catechin (2), p-coumaric acid (3) and vitexin (4).