Crude extract yield, total phenolics, and total flavonoids from the ink of sea hare (Dolabella auricularia)

Abstract

The crude extract yield, total phenolics and total flavonoids of the ethanol and water extracts of sea hare (Dolabella auricularia) were evaluated. The crude extract yield was determined gravimetrically while Folin-Ciocalteau and Aluminum chloride methods were used for the determination of the total phenolics and total flavonoids, respectively. The results showed that the crude extract yield for the ethanol fraction was higher (7.657 x 10 3 mg/ 100 mL of fresh ink sample) compared to water (2.937 x 10 3 mg/ 100 mL of fresh ink sample). The same pattern was also exhibited for both total phenolics and total flavonoids where a significant difference was observed at p<0.05. The total phenolics of the ethanol extract were higher at 2.77 mg gallic acid / mL compared to that of the water extract at only 0.75 mg gallic acid/ mL. While the total flavonoids of the ethanol extract was 32.75 mg quercetin/mL against that of the water extract which was only 9.42 mg quercetin/ mL. The results indicate that ethanol is a better solvent than water for the extraction of the phenolics, flavonoids and other components. Furthermore, the presence of phenolics and flavonoids in considerable quantity suggests that ink of sea hare is a potential source of bioactive compounds that have antioxidant activity which can be developed for nutritional or pharmacological use.