Castanea sativa mill. flowers as a source of bioactive phenolic compounds
Artigo de Conferência
Visão geral
Visão geral
resumo
In the Trás-os-Montes region of Portugal and across a good part of the Mediterranean countries, chestnut trees are a
considerable part of the landscape. These trees and their respective nuts have been important in the past and are still
a source of incomes for those regions. The chestnut tree and products, ·such as nuts, wood, leaves and flowers are
known to possess a myriad of applications [1]. In particular, infusions and decoctions of chestnut flowers have been
reported for different medical purposes [2], but their phytochemical profile and antioxidant activity are still mostly
unknown. Herein, decoctions and infusions of flowers from the two most appreciated chestnut cultivars (longal and
judia) in Trás-os-Montes, Portugal, were prepared and characterized with regard to their phenolic composition, which
was analyzed by HPLC-DAD-ESI/MS. Furthermore, the antioxidant activity was assessed in terms of free radical
scavenging capacity, reducing power and inhibition of lipid peroxidation in brain cell homogenates [2].
The individual polyphenol with the highest concentration in all samples was a trigalloyi-HHDP-glucoside, followed by
pentagalloyl glucose, whereas quercetin 3-0-glucuronide and a quercetin hexoside were the most abundant
flavonoids in judia and longal cultivars, respectively. The sample with the highest concentration of total polyphenols
was the infusion of judia, closely followed by the decoction of longal. The preparations of the cultivar judia presented
higher flavonoid levels than those of longal that in tern, displayed higher concentrations of hydrolyzable tannins.
Decoctions showed greater antioxidant activity than infusions, which might be explained by the longer time at boiling
point that decoctions were subjected to during extraction [2]. Overall, the decoction of the cultivar judia was the
sample with both the highest quantity of flavonoids and antioxidant activity. The obtained results support ancestral
claims about health benefits of infusions and decoctions of chestnut flowers. Moreover, due to the extremely potent
antioxidant activity observed, flower decoctions are currently being tested for their potencial use as natural
preservatives in food industry (research project PRODER n° 46577).
