Antioxidant and Cytotoxic Activities of Ethanolic Extracts of Mammea siamensis Flower

Abstract

In this work, the phytochemical content, antioxidant and cytotoxic activities of flower-derived ethanolic extracts of Mammea siamensis were examined. The yield crude of the semi-solid yellowish-brown extract was 11.13±0.11% w/w with a characteristic odor. Total phenolic content was determined as 115.27±0.003 μg GAE/mg dry weight and indicated that the extract was very rich in bioactive phenolics. However, moderate antioxidant activity was observed on DPPH radical scavenging (IC₅₀=35.92±1.127 μg/ml) being seven times weaker than that of ascorbic acid and also weak nitric oxide scavenging (IC₅₀=493±1.033 μg/ml). The cytotoxicity tests showed a dose-dependent toxicity in lesion fibroblasts, HaCaT and B16F1 melanoma cells, with fibroblasts being the less sensitive. Cytotoxicity was dramatic at concentrations ≥ 50 μg/ml for all cell lines and quasi-extinction was observed for concentrations included between 500 to 1000μg/ml. These results suggest that the flowers of Mammea siamensis can be a source of phenolic antioxidants with selective cytotoxicity and could be employed in pharmaceutical or cosmeceutical formulations.