Fig. 6.
HPLC profiles of solutions of in-laboratory and commercial VA extracts obtained by direct extraction with 85 % ethanol. Hypersil ODS C18 column (4.6 mm × 250 mm, 5µm, Hypersil) at room temperature. Mobile phase: 10 % methanol for 40 min in 90 % water, flow rate 0.6 ml/min. Detection was set at 431 nm and 664 nm.