Phytochemicals content, screening and antioxidant/pro-oxidant activities of Carapa procera (barks) (Meliaceae)

Abstract Total phenolic, flavonoid and tannin contents together with antioxidant and pro-oxidant activities of Carapa procera were investigated. The antioxidant activity of Carapa procera was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, ferric reducing/ antioxidant power (FRAP) method and 2,2′-azino bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) assay. The study of pro-oxidant activity was based on the power producing of iron ion in the Fenton reaction. The total phenolic content (TPC) of the extract was exhibiting high value of 8.2 mg gallic acid equivalents (GAE)/ g of dried Carapa. The study revealed a low percentage of flavonoids 0.04% in the extract and 0.24 mg of tannic acid equivalents (TAE)/g of dried Carapa for the tannin content (TC). Proanthocyanidins were less represented among the tannins 6.80% of the extract. The chromatographic fingerprints showed the presence of tannins and acid, like (+)-catechin, epicatechin, trans-4-hyroxicinnamic, 3,4-dihydroxicinnamic and acid chlorogenic. Carapa procera exhibited high antioxidant activity in the both DPPH and ABTS assays, being 10.45 mg Vitamin C equivalents/g of dried Carapa and 500 µmol Trolox/g of dried Carapa, respectively. The FRAP gave a good result 2.45 mg Vitamin C equivalents /g of dried Carapa. The pro-oxidant activity was 24.25 µg/ml of Carapa extract. The phytochemical screening was the subject of intensive investigations in order to identify the chemical constituents present in medicinal plants, such as Carapa procera and to evaluate their potential biological activities.