Determination of arbutin, rutin, total content of phenols and antioxidant capacity in fruits and leaves of lingonberry, Vaccinium vitis-idaea L. (Ericaceae)

The aim of this study was to determine arbutin, rutin, total phenols content (TCP) and total antioxidant capacity (AC) in the fruits and leaves of lingonberry, Vaccinium vitis-idaea L. (Ericaceae). Dry fruits and leaves of lingonberry were collected in Bosnia. For determination of AC was used Oxygen Radical Absorbance Capacity (ORAC) assay with trolox, a water soluble analogue of vitamin E, as a standard. The TCP was estimated by photometric method with Folin-Ciocalteau reagent at 765nm, with gallic acid as a standard. Arbutin and rutin determined using High Pressure Liquid Chromatography with electrochemical detection (HPLC-ED). As mobile phase it was used a mixture of water, methanol, acetonitrile, formic acid and isopropyl alcohol in proper proportion: 75.5: 12:6:5:1.5. Performance was done at 25° C with flow rate of 0.5ml/min and potential of 0.750 V. The TCP, expressed in milligramms of phenols per gramme of dry weight (mg/g_d.w.) was 12.7 in fruits, and 164.4 in leaves. The content of arbutin was 0.51mg/g_d.w. in leaves, and 0.04mg/g_d.w. in fruits. The content of rutin was 2.54mg/g_d.w. in leaves, and 0.06mg/g_d.w. in fruits. The values of AC, expressed as mmol trolox equivalents per gramme of dry weight (mM_TE/g_d.w.), were 46.45 mM_TE/g_d.w. in fruits, and 235.23 mM_TE/g_d.w. in leaves. The analysis has shown the higher content of phenols, arbutin and rutin in the leaves of lingonberry in comparison with fruits and higher AC in leaves. The higher AC in leaves correspond to the higher values of phenolic compounds.