Biological Activities of Some Compounds Isolated from The Flowers of Sesbania grandiflora L.

Abstract

Sesbania grandiflora, mainly bark, leaves, and roots, has been widely used in traditional Asian medicine for the treatment of diabetes, respiratory inflammation, and liver disorders. This study aimed to evaluate the phytochemical constituents, antioxidant activity, and α-glucosidase inhibitory potential of Sesbania grandiflora flowers to support their medicinal utilization. Dried flowers (1.0 kg) were extracted with 70% ethanol to obtain the crude extract, followed by liquido–liquid partitioning into five fractions: petroleum ether, chloroform, ethyl acetate, n-butanol, and aqueous fractions. The chloroform fraction exhibited the strongest antioxidant activity in the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay with an IC₅₀ of (53.24 ± 2.46) µg/mL, whereas the ethyl acetate fraction showed notable α-glucosidase inhibitory activity with an IC₅₀ of (175.90 ± 2.17) µg/mL. Four compounds were isolated from the chloroform and ethyl acetate fractions, including β-amyrin, baicalein, kaempferol, and p-hydroxybenzoic acid. Notably, baicalein and p-hydroxybenzoic acid were reported for the first time from S. grandiflora. Bioactivity evaluation revealed strong antioxidant activity of baicalein, IC₅₀ (4.43 ± 0.082) µM, and potent α-glucosidase inhibition by kaempferol, IC₅₀ (24.27 ± 0.32) µM, highlighting the potential of S. grandiflora flowers as a promising medicinal resource.