In vitro toxicity and antioxidant activities of Hedychium gardnerianum from S. Miguel (Azores)

There is an increasing interest in antioxidants, particularly in those intended to prevent the presumed deleterious effects of free radicals in the human body, and to prevent the deterioration of fats and other constituents of foodstuffs. In both cases, there is a preference for antioxidants from natural rather than from synthetic sources. Numerous studies on essential oils have been performed in order to investigate the effects of these fragrances on many biological systems. Hedychium gardnerianum, an infestant plant in the Azores (Portugal) is used in many popular applications but not as natural medicinal drug. Therefore, essential oils from the leaves of three different places in S. Miguel Island were extracted by hydrodistillation and assayed for their antioxidant and toxicity properties, using the stable free radical diphenylpicrylhydrazyl test. [1] and Artemia salina cytotoxicity assay [2], respectively. All the fractions assayed show high antioxidant activity with EC50 values between 8.46 and 28.76µg/mL with the essential oil from Furnas the most active. A. salina LC50 toxicity values are within the range 300.1 and 379.2µg/mL with the essential oil from Fogo with the higher toxic effect. Our results indicate that the higher antioxidant activity the lower the toxicity in A. salina. These results are a very good preliminary approach for the antitumor and pesticidal activity of these samples. However, further studies must be performed in order to elucidate the mechanism of action of these essential oils on cytotoxicity tests.

References: 1. Molyneux P (2004). Songklanakarin J. Sci. Technol. 26(2).

2. Solis P, Wright C, Anderson M, Gupta M, Phillipson D (1993). Planta Med. 59:250–252.