Antioxidant Activity and Phytochemical Composition of the Leaves of Solanum guaraniticum A. St.-Hil
Marina Zadra1 
Mariana Piana1 
Thiele Faccim de Brum1 
Aline Augusti Boligon1 
Robson Borba de Freitas1 
Michel Mansur Machado1 
Sílvio Terra Stefanello1 
Félix Alexandre Antunes Soares1 
Solanum guaraniticum is a shrub belonging to the Solanaceae family popularly known in Brazil as jurubeba or false-jurubeba. The aim of this study was to evaluate the antioxidant activity of crude extract and chloroform, ethyl acetate and n-butanol fractions from its leaves, verifying the ability to remove reactive species and identify and quantify phenolic compounds. The ethyl acetate fraction showed the highest amount of total polyphenols (546.57 ± 2.35 mg gallic acid equivalent/g) and the lowest IC50 (9.11 ± 0.75 µg/mL) by the DPPH method. Furthermore, the chloroform fraction presented the highest content of flavonoids (75.73 ± 0.34 mg rutin equivalents/g), tannins (56.03 ± 0.68 mg catechin equivalents/g) and alkaloids (10.79 ± 0.06 mg/g). This fraction was effective in the scavenging of reactive species by 2′,7′-dichlorofluorescein diacetate assay, in addition to completely reducing protein carbonyl content and reducing lipid peroxidation at basal levels even at low concentrations. Chlorogenic, caffeic and rosmarinic acids were identified and quantified by HPLC/DAD. These results show that S. guaraniticum is rich in phenolic compounds and has potential as an antioxidant.