Figure 4.
UHPLC profiles of different hawthorn extracts obtained from different extraction modes for 1 mm ground hawthorn flowering tops (left) and from the infusion of different parts (flowering tops vs. flowers) or different states (fresh vs. dry) of hawthorn (right), as indicated in the figure (see experimental part for the different extraction protocols). Experimental conditions: Luna® Omega polar C18 column (1.6 μm, 100 × 2.1 mm), binary solvent system: water/formic acid (1‰, v/v) as solvent A and acetonitrile/formic acid (1‰, v/v) as solvent B. Gradient program: 5% B, then increase of B to 100% in 30 min with a convex increase, flow rate: 0.4 mL.min−1, injection volume: 4 μL. Column temperature: 35 °C. UV monitoring at 273 nm. UV–Vis spectra recorded between 200 and 550 nm. Lot number for raw and ground flowering tops materials: 20335. Lot number for flowers: 20334. Fresh flowering tops: harvested in 2017 and extracted one week after (fresh) or one year after (fresh after one year). Peak identification: 1 = cyanidin, 2 = 5-O-caffeoylquinic acid, 3 = chlorogenic acid, 4 = procyanidin B2, 5 = epicatechin, 6 = procyanidin C1, 7 = cinnamtannin A2, 8 = vitexin-2-O-rhamnoside, 9 = hyperoside, 11 = isoquercetin, 12 = apigenin C-hexoside.