Acute toxicity of aqueous extract of Curcuma longa L. on Artemia salina L.

Abstract

Curcuma longa is a plant of medicinal value, popularly known as saffron or turmeric. The rhizomes of this plant are rich in curcuminoids, compounds responsible for pharmacological activity. Due to the increase in consumption of this plant in the general population, this study aimed to evaluate the toxic potential of the aqueous extract obtained from the rhizomes of Curcuma longa, using the bioassay with Artemia salina. The cysts of Artemia salina were incubated for a period of 30 hours, followed by the collection of the nauplii which were subsequently exposed to different concentrations of the extract obtained through decoction (50, 100, 200, 400 and 800 μg/mL-1). For each treatment, four replicates were used. The nauplii (10 per repetition) were kept in contact with the solution for 48 hours, and the survival rate was evaluated every 24 hours. After 24 hours of exposure to the aqueous extract, no significant mortality was observed at any of the evaluated concentrations. However, after 48 hours of exposure, there was significant mortality from the concentration of 100 μg/mL-1, resulting in a mortality rate of 32.35%. At the intermediate concentration (400 μg/mL-1), a mortality rate of 61.76% was observed, while at the highest concentration (800 μg/mL-1), 100% mortality of exposed organisms was recorded. The mean lethal concentration (LC50) obtained was 186.5 μg/mL-1, thus classifying the aqueous extract as moderately toxic. Therefore, caution is recommended when using tea from this plant, since the aqueous extract has shown toxicity in relation to Artemia salina.