Solvents for Extraction of Antidiabetic, Iron Chelating, and Antioxidative Properties from Bottle Gourd Fruit

Abstract

Bottle Gourd, Lagenaria siceraria (Molina) Standley (LS), fruit contain antidiabetic and antioxidant properties. The effect of solvents on extraction of bioactive components has not been studied. The choice of solvent is a major factor for extraction of natural products. The research compared alpha-amylase, alpha-glucosidase, and beta-carotene bleaching inhibitory and iron chelating potential of LS fruit extracts in the solvents water, acetone, ethanol, ethyl acetate, chloroform, and methanol and their ability to extract phenolics and flavonoids from the fruit. The methanolic extract was further fractionated into solvents of increasing polarity to separate phytochemicals based on their polarity. Ethyl acetate proved to be the best solvent to extract phenolics; acetone was best to extract flavonoids. The aqueous decoction was the most potent alpha-glucosidase inhibitor (IC50 0.28 mg∙mL−1) and ethyl acetate extract was the most effective alpha-amylase inhibitor (IC50 0.2 mg∙mL−1) and had the highest beta-carotene bleaching inhibitory potential (IC50 3.16 mg∙mL−1). The iron chelating potential of the ethyl acetate extract was second to the chloroform extract (IC50 82.11 and 199.2 µg∙m−1, respectively). The alpha-glucosidase inhibitory activities of the ether and ethyl acetate fractions were IC50 0.32 and 0.33 mg∙mL−1, respectively. The ethyl acetate fraction had IC50 0.26 mg∙mL−1 in alpha-amylase inhibitory activity compared to acarbose with IC50 0.23 mg∙mL−1. The ethyl acetate extract and aqueous decoction exhibited the best antidiabetic and antioxidative activities indicating the effectiveness of these solvents for extraction of bioactive substances.