Antioxidant and anti-inflammatory activities of Arbutus unedo aqueous extract
Objective: To evaluate the antioxidant and anti-inflammatory activities of aqueous extract of Arbutus unedo (A. unedo) leaves. Methods: In this context, the in vitro antioxidant activity was demonstrated by 2,2- diphenyl-1-picrylhydrazyl, hydroxyl radical and H2O2 radical scavenging, ferrous ion chelating, ferric reducing power, total antioxidant capacity and by the protection against peroxidation of β-carotene-linoleic acid in emulsion. The anti-inflammatory activity was evaluated first by studying the membrane of human red blood cells against different hypotonic concentrations of NaCl and against heat, inhibiting the denaturation of albumin. Results: Total phenolic and flavonoid content were found respectively [(207.84 ± 15.03) mg gallic acid equivalent/g, and (13.070 ± 0.096) mg quercetin equivalent/g]. The extract displayed significant scavenging activity of some radicals such as 2,2-diphenyl-1- picrylhydrazyl [IC50 at (7.956 ± 0.278) μg/mL], ˙OH [IC50 = (1 015.74 ± 46.35 μg/ mL)], H2O2 [IC50 = (114.77 ± 16.86) μg/mL] and showed a good antioxidant activity through ferrous ion chelating activity [IC50 = (1 014.30 ± 36.21) μg/mL], ferric reducing power [IC50 = (156.55 ± 17.40) μg/mL], total antioxidant capacity [IC50 = (461.67 ± 4.16) μg/mL] and β-carotene-linoleic acid protection against peroxidation [I % = (87.04 ± 1.21)% at 1 000 μg/mL]. Conclusions: A. unedo showed in vitro anti-inflammatory activity by inhibiting the heat induced albumin denaturation and red blood cells membrane stabilization. Our results show that aqueous leaf extract of A. unedo has good antioxidant activity and interesting anti-inflammatory properties. A. unedo aqueous extract can be used to prevent oxidative and inflammatory processes.
Supported by University Hospital Nedir Mohamed of Tizi-Ouzou (Grant No. cnp-um/8819-136/2014) and Laboratory Analytical Biochemistry & Biotechnology Research (LABAB), Faculty of Biological Sciences and Agricultural Sciences, Mouloud Mammeri University of Tizi-Ouzou, Algeria (Grant No. bn- 001375-14-993).