Comparative studies on antioxidant activities of extracts from the leaf, stem and berry of Myrtus communis L

Myrtle (Myrtus communis L.) leaf, stem and berry extracts were prepared to examine the total phenolics, flavonoids and condensed tannins contents. The antioxidant activities of crude extracts, ethyl acetate fraction, butanolic fraction, tannins and anthocyanins from these parts of plant were evaluated in vitro using reducing power and DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging tests. The total phenol contents varied between different myrtle parts: leaf extract had higher total phenol content expressed as gallic acid equivalents (GAE)/g dry matter (119.23 ± 0.77 mg/g) than stem (112.96 ± 0.53 mg/g) and berry (70.26 ± 0.71 mg/g) extracts. The highest contents of total flavonoids and condensed tannins expressed as catechin equivalents (CE)/g dry matter were observed in leaf (6.56 ± 0.57 mg/g) and berry extracts (27.20 ± 0.25 mg/g), respectively. The ethyl acetate fraction of leaf exerted greater antioxidant activity followed by leaf butanolic fraction and berry anthocyanins extracts. The efficient concentrations (EC50) of this fraction were 0.09 ± 0.002 mg/mL for reducing power and 0.26 ± 0.004 mg/mL for scavenging DPPH radical. This better activity was confirmed by thin layer chromatography (TLC), where we identified the presence of gallic acid in all parts of plant, catechin in leaf and quercetin in berry.