Exploration of the Mizo Traditional Medicine: Pharmacognostic Studies of the Indigenous Medicinal Plant, Erythrina stricta

Abstract

Objectives:The study aimed to understand the range of medicinal applications of Erythrina stricta Roxb. (Fabaceae) among the Mizo people of India, and to analyse the pharmacological properties of the bark extract. Methods: Ethnomedicinal investigation was conducted among traditional healers and users. The petroleum ether extract of the bark was analysed for its phytochemical components. Antioxidant property was evaluated by DPPH (2,2diphenyl-1-picrylhydrazyl) radical scavenging assay. Total antioxidant capacity, flavonoid and total phenolic contents of the plant extract were assessed by using the phosphomolybdate method, Folin-Ciocalteu assay and aluminium chloride assay respectively. Antimicrobial activity was tested on two Gramnegative and four Gram-positive bacteria. Findings: E. stricta was used for the treatment of stomach ulcer, diabetic blisters, intestinal roundworm infection, skin infection, sores and wounds. The plant extract contained phytochemicals like alkaloids, flavonoids, phenols, tannins, amino acids and proteins, phytosterols and triterpenoids. The extract showed concentrationdependent antioxidant activity against DPPH; showing an IC 50 value of 3.33±0.024 µg/ml compared to 0.23±0.095 µg/ml for the reference butylated hydroxytoluene. The total antioxidant capacity was 12.01±0.33 mg ascorbic acid equivalent per gram (AAE/g) of the dry extract; the total phenolic content was 3.77±0.12 mg gallic acid equivalent per gram (GAE/g) of the dry extract; while the total flavonoid content was 7.75±1.13 mg quercetin equivalent per gram (QE/g) of the dry extract. The extract effectively inhibited the growth of two Gram-positive bacteria, Bacillus cereus and Staphylococcus aureus, and one Gram-negative species, Klebsiella pneumoniae. Novelty: E. stricta was found to have important medicinal applications and pharmacological potential, and needs systematic conservation and propagation. It showed high antioxidant values, and species-specific antibacterial activities.