Exploring the therapeutic potential of leaf extract of Nephrolepis brownii (Desv.) Hovenkamp & Miyam.: An integrative study on antioxidant and anti-diabetic activities

Diabetes mellitus is a major worldwide health problem that is frequently associated to elevated oxidative stress. Medicinal herbs, recognized for their high antioxidant content, provide a potential approach to diabetes therapy. Despite their long history of usage in traditional medicine, ferns such as Nephrolepis brownii have received little attention in terms of therapeutic potential. Hence, the current study investigates the antioxidant activity of N. brownii leaf extract in water using the DPPH radical scavenging assay. The anti-diabetic activities of the leaf extract are evaluated using α-amylase and α-glucosidase inhibition tests, with effectiveness compared to the standard medication acarbose. The results reveal substantial antioxidant potential in N. brownii leaf extract in water (70.0 % inhibition at 1000 μg/mL), comparable to the antioxidant activity of ascorbic acid. The extract showed a concentration-dependent inhibition of α-amylase (IC50: 67.70 μg/mL) and α-glucosidase (IC50: 76.37 μg/mL), albeit slightly less potent than acarbose. These findings highlight the potential N. brownii as a natural antioxidant and anti-diabetic agent and this is the first report on this plant. This work contributes valuable insights into the diverse therapeutic properties of N. brownii, indicating its potential as a natural source of antioxidants and a subject for further investigation in anti-diabetic research.