Extracts from egg strings of sea hare (Dolabella auricularia): Yield, antioxidant activity, zoochemical profile, and toxicity

Abstract

This study aimed to evaluate the crude extract yield, secondary metabolites, antioxidant and cytotoxic activities of the different crude extracts of egg strings from sea hare (Dolabella auricularia) taken from Guang-guang, Pujada Bay, Davao Oriental. The 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method showed that the antioxidant activity of the crude extract of ethanol was greater than ethyl acetate and hexane in a dose-dependent manner. Ethanolic extract with a yield of 28.96 mg/g showed the highest percentage inhibition of 24.86% at 1000 µg/mL. The antioxidant activity may be attributed to known antioxidant metabolites, especially the phenolic substances, and some forms of synergism. The result also revealed the presence of alkaloids, saponins, steroids, tannins, and terpeneoids. On the other hand, the brine shrimp assay for all extracts gave LC50 > 1,000 µg/mL which indicated the absence of potential cytotoxic substances. The result of this study increases the nutritional potential values and provide baseline information for another possible source of future novel antioxidants that can be used in food and pharmaceutical industries. However, further investigations must be conducted to explore other biological activities of the extracts.