Variação sazonal dos teores de compostos fenólicos e polifenólicos no extrato aquoso das folhas de Psidium guineense Sw (Myrtaceae)

Abstract

Psidium guineense Sw. (araça-do-campo) is a Myrtaceae native to Brazil, widely used in folk medicine to treat gastrointestinal and genitourinary conditions. Pharmacological and chemical studies of its leaves have confirmed several biological activities, such as antioxidant, antifungal, antibacterial, anti-inflammatory, antimicrobial and antiproliferative properties, due to its rich composition of essential oils and other bioactive compounds. Understanding the relevance of knowledge of phytochemical composition, the objective of this study was to investigate the influence of seasonality on the variation of bioactive constituents in aqueous extracts of P. guineense leaves collected throughout the year. The lyophilized extracts demonstrated that the levels of phenolic and polyphenolic compounds vary significantly according to the season, evidencing a strong influence of seasonality on the secondary metabolism of the plant. In particular, the concentrations of total phenolics, flavonoids, flavonols and condensed tannins showed a marked seasonal dependence, with summer presenting the highest accumulation of most of the investigated compounds. These findings highlight the importance of the collection season in obtaining plant materials with an optimized phytochemical profile, a crucial factor for future biotechnological or pharmaceutical applications.