Antioxidant, Antibacterial, and Antidiabetic Activities of Aleuritopteris bicolor From Nepal: A LC-MS, In Vitro, and In Silico Investigations to Establish Its Potential as a Therapeutic Candidate

Abstract

Aleuritopteris bicolor (Family: Pteridaceae; Nepalese name: Raani Sinka) is an edible fern native to Nepal, India, China, Bangladesh, Sri Lanka, and Pakistan. Ethnomedicinal practitioners from various ethnic tribes in Nepal have traditionally prescribed it to heal wounds, diarrhea, dysentery, and gastritis. However, scientific evidence supporting these efficacies remains limited until January 2025. In the present study, we aimed to validate these traditional uses through chemical, in vitro, and in silico analyses of the plant's hydroalcoholic extract. The 70% methanolic extract of the plant exhibited potent DPPH free radical scavenging activity with an IC₅₀ of 20.54 ± 4.4 μg/mL. The extract also demonstrated potent and dose-dependent antibacterial activity against Staphylococcus aureus (zone of inhibition: 8-12 mm and minimum inhibitory concentration: 3125 μg/mL), assessed using well diffusion and broth microdilution techniques. However, the plant extract was found to be a weak inhibitor of the enzyme alpha-amylase. Phytochemical analysis using LC-MS revealed the presence of chlorogenic acid, kumatakenin, quercetin 3-O-glucoside, and rhamnocitrin 3-O-glucoside; which, when docked against penicillin-binding protein's catalytic residues (SER 403, LYS 406, SER 462, ASN 464, and THR 600), showed binding energies ranging from -6.3 to -7.1 kcal/mol, suggesting prominent molecular interactions compared with meropenem antibiotics. Furthermore, kumatakenin satisfied Lipinski's parameters for drug-likeness, indicating its great potential as a drug candidate. The current study provides scientific evidence for the potent phytoconstituents with antioxidant and antibacterial potential of A. bicolor for the first time, highlighting its potential for topical application in treating bacterial infectious wounds.

Keywords: Aleuritopteris bicolor; LC-MS analysis; antibacterial activity; antioxidant activity; in silico molecular docking.