Evaluation of Phytochemical Composition, Antioxidant Activity, and Analgesic Effects of Polyalthia Longifolia Leaves (Masquaerade)

Abstract

Polyalthia longifolia is a plant with a rich medicinal history, its name derived from the Greek words "poly," meaning many, and "althea,"  meaning cure. This study aimed to evaluate the phytochemical composition, antioxidant potential, and analgesic activity of the  methanolic extract of Polyalthia longifolia leaves. Phytochemical analysis was conducted using standard qualitative methods, while the antioxidant activity was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and analgesic activity was determined through  the acetic acid-induced writhing test. Phytochemical screening revealed the presence of alkaloids, flavonoids, saponins, tannins,  carbohydrates, cardiac glycosides, steroids, and triterpenes, whereas anthraquinones not detected. The extract exhibited significant  antioxidant activity, with an IC₅₀ value of 7.122 µg/mL, which was slightly less potent than that of Butylated Hydroxytoluene (BHT) with  an IC₅₀ value of 4.942 µg/mL. The methanol extract demonstrated high free radical scavenging activity (99.30% at 1000 µg/mL) compared  to BHT (90.1% at 1000 µg/mL). The analgesic evaluation showed dose-dependent effects, with the 300 mg/kg dose achieving  the highest pain inhibition (100%), followed by 150 mg/kg (98.1% inhibition) and 75 mg/kg (74.03% inhibition). The analgesic effect  increased proportionally with dosage. These findings suggest that Polyalthia longifolia leaves contain bioactive compounds with notable  antioxidant and significant analgesic activities, highlighting their potential for pharmaceutical and nutraceutical applications.