Phytochemical analysis, antioxidant and anti-inflammatory activities of Helichrysum stoechas (L.) Moench extracts

This work aimed at investigating the phenolic composition, antioxidant and anti-inflammatory activities of ethyl acetate (EAE) and butanolic (BuE) extracts obtained from the aerial parts of Helichrysum stoechas (L.) Moench. EAE extract showed the highest levels of polyphenols (589.65 +/- 35.58 mg GAE/g extract) and flavonoids (84.78 +/- 8.07 mg QE/g extract). The LC-ESI-MS results indicate various vital phenolics, including isoquercitrin, rutin, ferulic acid and chlorogenic acid. The EAE and BuE extracts (2 mg/ear) exhibited a significant inhibition (p < 0.001) of croton oil-induced ear aedema by 86% and 64%, respectively, and they reduced significantly (p < 0.001) the number of infiltrating leukocytes by 84% and 66% of inhibition, respectively. These extracts inhibited significantly (p < 0.001) the protein denaturation and stabilised the erythrocytes membrane. Besides, both extracts exerted antioxidant effect by scavenging hydrogen peroxide, hydroxyl radicals and superoxide anion radicals. Moreover, they exerted a significant protective effect (p < 0.001) against AAPH-induced erythrocyte hemolysis. At 40 mu g/mL, the half hemolysis times were 185.58 +/- 7.45 and 138.50 +/- 1.57 min, respectively. These values are better than those obtained with Trolox (115.47 +/- 0.41 min), used as a reference. Results from this study suggest that H. stoechas may represent a prospective source of natural antioxidants and anti-inflammatory agents.