Species from the Garcinia genus (Clusiaceae family) are used in the treatment of many diseases and metabolic disorders frequently associated with the oxidative stress. The characteristic metabolites found in this genus are xanthones and benzophenones, which have antioxidant properties, among relevant biological potentials. This review provides a specific vision about antioxidant activity of Garcinia species, reporting in vitro and in vivo assays, described from the last five years. The research about antioxidant properties of Garcinia species and their constituents can be directed in the development of new medicines and drugs.

Species from Thuja genus (Cupressaceae) are found in Brazil, North America and Asia. In the traditional medicine, these plants are used in the treatment of cough, skin allergies, and asthma. In Brazil, Thuja species are also used in the ornamentation of urban areas. Different parts of these plants displayed insecticidal, antitumor, and antioxidant activities. The essential oil of the leaves from Thuja spp. are constituted by monoterpenes and sesquiterpenes. The main substances found in the extracts of these species are flavonoids, which display relevant biological activities. This brief review shows recent phytochemical studies involving T. orientalis and T. occidentalis, as well as 40 constituents isolated from these species. The existing pharmacological potential justifies the growing scientific interest in this genus.

This work reports a new application for a well-known medicinal plant used in Brazil. The green synthesis of silver nanoparticles (AgNPs) using the aqueous extract of Monteverdia ilicifolia (MI) leaves as stabilizing and reducing agent is described. The AgNPs-MI obtained were characterized by UV-VIS, FTIR, and Raman spectroscopies, DLS, zeta potential and FEG-SEM, which demonstrated that M. ilicifolia was effective at capping the AgNPs, yielding stable suspensions. These nanoparticles were deposited on glassy carbon electrodes, and they were efficiently applied as electrochemical sensors for the determination of dopamine (DA) using square wave voltammetry (SWV). The AgNPs-MI improved the electrochemical properties of the electrodes and enhanced their electroanalytical performance. The developed sensing device presented detection and quantification limits equal to 0.52 and 1.74 ?mol�L�1, respectively, towards DA determination. The proposed electrochemical sensor quantified this neurotransmitter successfully, confirming its potential as a new promising analytical detection tool for DA quality control.