RESUMO
Theobroma speciosum, known as "cacauí" in Brazil, is considered a prominent unconventional food plant. The objective of this work was to evaluate the chemical profiles, antioxidant capacity and minerals of the aqueous extract and fractions from its flowers. The identified compounds were sugars, organic acids and phenolics compounds such as citric, malic and protocatechuic acids, quercetin, quercetin pentoside and quercetin-3-O-glucoside. The extract was rich in phenolic compounds (640 mg GAE g-1). Furthermore, fractions also presented phenolic compounds from 170.7 to 560.7 mg GAE g-1 (mainly protocatechuic acid, quercetin and derivatives), which influenced on the high antioxidant capacity in DPPH, ABTS, FRAP and co-oxidation ß-carotene/linolenic acid assays. Flowers presented potassium (115 ± 2 µg mL-1), magnesium (18.4 ± 0.2 µg mL-1), phosphorus (7.0 ± 0.0 µg mL-1) and calcium (3.1 ± 0.1 µg mL-1). Moreover, the flowers aqueous extract represents a new promising food source rich in antioxidant compounds.
Assuntos
Antioxidantes/análise , Cacau/química , Flores/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , Fenóis/análiseRESUMO
There are relatively few studies concerning the use of coffee leaves for medicinal purposes and the composition of secondary plant substances. Therefore, we identified and quantitated polyphenolic compounds along with caffeine present in methanol extracts of Coffea arabica leaves from three different regions of Brazil (Ceará, Minas Gerais and São Paulo) by HPLC-ESI-MS. In addition, correlations between polyphenolic content of the coffee leaves and antioxidant assays DPPH, FRAP and ORAC were evaluated. Fifteen compounds belonging to three classes of polyphenols (xanthones, chlorogenic acids and flavonoids) along with the alkaloid caffeine were detected. The mean concentration of total polyphenolic compounds in the leaves of C. arabica, harvested from three different regions of Brazil was quite variable. The highest values were detected in the coffee leaves harvested in Minas Gerais (nâ¯=â¯4) at 40.80(13.00) g/kg (SD), followed by coffee leaves harvested in São Paulo (nâ¯=â¯20) at 24.79(20.19) g/kg, and the lowest in coffee leaves harvested in Ceará (nâ¯=â¯11) in the Northeast of Brazil at 10.30(5.61) g/kg. The three classes of polyphenols, all showed excellent correlations in the antioxidant assays. Coffee leaf tea, appears to be an excellent functional beverage, with its high content of polyphenolic compounds, which may render positive biologic effects, when inbibed as part of the normal human diet.