Introduction: In this study, we used dichloromethane (DCM) and methanol (MeOH) extracts of the Zingiber zerumbet rhizome to evaluate brine shrimp lethality and larvicidal activity on Aedes aegypti and Anopheles nuneztovari mosquitoes. Methods: Bioassays were performed by exposing third-instar larvae of each mosquito species to the DCM or MeOH extracts. Results: Probit analysis with DCM and MeOH extracts demonst...
Isoprene, C5H8, is a biogenic volatile compound emitted from plants and animals, playing an important role in atmospheric chemistry. In this work, we have studied the ionic fragmentation of the isoprene molecule induced by high energy photons (synchrotron radiation), both at the valence (12.0, 14.0, 16.0, 18.0, and 21.0 eV) and carbon 1s edge (270 and 310 eV, respectively, below and above edge) energies. The io...
Guarana (Paullinia cupana) is largely consumed in Brazil in high energy drinks and dietary supplements because of its stimulant activity on the central nervous system. Although previous studies have indicated that guarana has some protective effects in Parkinson's (PD), Alzheimer's (AD), and Huntington's (HD) disease models, the underlying mechanisms are unknown. Here, we investigated the protective effects of ...
Minquartia guianensis, popularly known as acariquara, was phytochemically investigated. The following triterpenes were isolated from the dichloromethane extract of leaves: lupen-3-one (1), taraxer-3-one (2) and oleanolic acid (3). The dichloromethane extract of branches yielded the triterpene 3β-methoxy-lup-20(29)-ene (4). The chemical structures were characterized by NMR data. Plant extracts, substance 3, squa...
Duroia macrophylla popularly known as "cabeça-de-urubú, " "apuruí," or "puruí-grande-da-mata" occurs in the Amazon Forest. Its leaves and branches were collected twice and extracted with dichloromethane and methanol. All extracts were subjected to phytochemical investigation and terpenes and flavonoids were found in all dichloromethane and methanol extracts, respectively. Methanol extracts from both branches (1...
Introduction: In vitro bioassays were performed to access the larvicidal activity of crude extracts from the endophytic fungus Pestalotiopsis virgulata (Melanconiales, Amphisphaeriaceae) and the saprophytic fungus Pycnoporus sanguineus (Basidiomycetes, Polyporaceae) against the mosquitoes Aedes aegypti and Anopheles nuneztovari. Methods: The extracts were tested at concentrations of 100, 200, 300, 400 and 500pp...
An alternative spectrophotometric ferric reducing activity power (FRAP) method for quantification of total reducing capacity (TRC) was developed. The method is based on the reduction of FeIII to FeII by antioxidant compounds containing 2,2’-bipyridine (bipy) in aqueous solution. Absorbance values recorded at 521 nm, characteristic of the Fe(bipy)3 2+ complex formed, were used to determine the TRC of some plants...
Background: The Amazon is the largest rainforest in the world and is home to a rich biodiversity of medicinal plants. Several of these plants are used by the local population for the treatment of diseases, many of those with probable anti-inflammatory effect. The aim of the present investigation was to evaluate the in vitro antioxidant and anti-peroxidases potential of the ethanol extracts of five plants from t...
The inorganic composition of the bark and leaf of a plant from the Amazon rainforest, Andira surinamensis, was determined using two non-destructive, multi-element techniques: X-ray fluorescence (XRF) and Rutherford backscattering spectrometry (RBS). XRF measurements were made using both a conventional X-ray source and synchrotron radiation. It was observed that although magnesium, aluminum, silicon, phosphorus,...