Fig. 2

HPLC chromatogram of 1 ml standard mixture of polyphenolic compounds. Peaks: 1, arbutin (5 µg); 2, gallic acid (4 µg); 3, hydroquinone (4 µg); 4, (+)-catechin hydrate (10 µg); 5, vanillic acid (4 µg); 6, caffeic acid (3 µg); 7, syringic acid (3 µg); 8, (–)-epicatechin (5 µg); 9, vanillin (3 µg); 10, p-coumaric acid (2 µg); 11, trans-ferulic acid (3 µg); 12, rutin hydrate (6 µg); 13, ellagic acid (10 µg); 14, benzoic acid (8 µg); 15, rosmarinic acid (4 µg); 16, myricetin (4 µg); 17, quercetin (2 µg); 18, trans-cinnamic acid (1 µg); 19, kaempferol (2 µg)