Antioxidant activity and zebrafish teratogenicity of hydroalcoholic Moringa oleifera L. leaf extracts

Abstract

PurposeMoringa oleifera (MO) is a herbal remedy that is rich in essential amino acids and phytochemicals in the leaves, seeds and pods. It is becoming a famous food in various ethnic groups, and the consumption is increasing worldwide. However, there is no safety profile of the hydroalcoholic MO leaf extracts, or documented teratogenicity aspect. This study was sought to compare the antioxidant activity and the teratogenicity of hydroalcoholic MO leaf extracts in the zebrafish embryo.Design/methodology/approachMO leaves were extracted with aqueous alcohols (ethanol or methanol: water, 80:20 v/v) using the Soxhlet method. The antioxidant capacity was determined using DPPH assay. The concentrations of extracts ranging from 3 to 1,000 µg/mL were used to examine the toxicity and teratogenicity on the zebrafish embryo.FindingsBoth hydroalcoholic MO leaf extracts were positive for alkaloids, terpenoids, steroids, tannins, flavonoids, phenols, coumarins, quinones and glycosides, except saponins only absent in aqueous methanol extract. The antioxidant capacity based on lC50, was 15.92 ± 3.62 mg/mL for aqueous methanolic and 25.28 ± 2.89 mg/mL for aqueous ethanolic extract. For acute toxicity, the aqueous methanolic extract has lower LC50 (163.87 ± 12.88 µg/mL) compared to aqueous ethanolic extract (337.48 ± 30.04 µg/mL). The embryo treated with aqueous methanolic extract showed phenotypic defect but not on the aqueous ethanolic extract.Originality/valueThis study suggests that aqueous methanol of MO leaves extract has better antioxidant capacity compared to ethanol, and ethanolic leaf extract is safer (higher LC50 and no teratogenicity) than methanolic extract.