Avaliação biológica e química de extratos brutos de Hedychium coronarium: atividade antibacteriana e antioxidante

Abstract

The search for new bioactive compounds from plant matrices is fundamental for combating bacterial resistance and oxidative stress. This study aimed to evaluate the phytochemical, antioxidant, and antimicrobial potential of methanolic extracts from the leaves and flowers of Hedychium coronarium. The methodology consisted of obtaining extracts through ultrasound-assisted maceration, followed by the quantification of total phenolic compounds and the evaluation of antioxidant activity using ABTS radical scavenging and Reducing Power methods. Antibacterial activity was tested using the disc diffusion method against Staphylococcus aureus and Escherichia coli strains. The results demonstrated that the leaf extract has a higher phenolic content compared to the flowers, reflecting superior antioxidant activity. In the Reducing Power assay, leaves showed 223.78 mg EBHT/100g and flowers 112.89 mg EBHT/100g, revealing statistically significant differences (p<0.05) by the Scott-Knott test. A clear dose-dependent behavior was observed, in which increasing concentrations led to an increase in absorbance. Regarding antimicrobial activity, no inhibition zones were observed. The discussion indicates that the absence of zones may be related to the low diffusibility of the crude compounds in the solid agar matrix and not necessarily to biological inactivity. It is concluded that the aerial parts of H. coronarium show relevant antioxidant potential, with the leaf fraction being the most promising.