Identification of flavonoids in Hymenaea martiana Hayne (Fabaceae) by HPLC-DAD-MSn analysis.

Hymenaea martiana is a native tree known in Brazil as 'jatobá' and used in folk medicine to treat pain and inflammation. The aim of this work was to identify the flavonoids present in the crude ethanolic extract and ethyl acetate fraction using HPLC-DAD and LC-MSn analysis. The ethanolic extract was partitioned to obtain the ethyl acetate fraction. The analysis of astilbin content also was carried out by HPLC analysis. HPLC-DAD-ESI/MSn analysis of the ethanolic extract and ethyl acetate fraction revealed the presence of eleven peaks in the chromatograms, and all these peaks were identified: taxifolin, eucryphin, astilbin and 3 diastereoisomers, engeletin and 2 diastereoisomers, quercitrin and 2,6,3',4'-tetrahydroxy-2-benzylcoumaran-3-one. The ethyl acetate fraction had a higher astilbin concentration (151.87 µg/mL) than the ethanolic extract (40.13 µg/mL). In conclusion, the species could be considered a good source of flavonoids, which can be related to the main chemotaxonomic markers for the genus Hymenaea.

Chemical Analysis and Evaluation of Antioxidant, Antimicrobial, and Photoprotective Activities of Schinopsis brasiliensis Engl. (Anacardiaceae).

Schinopsis brasiliensis Engl. is a native plant of Caatinga which has high concentrations of compounds capable of absorbing ultraviolet light, suggesting its potential application for the development of sunscreen preparations. After its identification and collection, this vegetable drug was submitted to a physicochemical analysis through the preparation of ethanolic extract. The phytochemical screening and analysis of extracts were carried out by high-performance liquid chromatography (HPLC) evaluation. The antioxidant activity of the extract was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and ß-carotene bleaching test. Inhibitory hemolytic activity and morphological deformation of erythrocytes induced by H2O2 were also demonstrated and the antimicrobial activity was analyzed by the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) method. For the in vitro determination of the sun protection factor (SPF), the spectrophotometric method was used. From the analyses carried out with this species, this plant showed significant results for the antioxidant and antimicrobial activities, as well as sunscreen action. Important flavonoids were identified. These data are an important step for the development of new photoprotective cosmetic with Caatinga species, revealing importance and representing another incentive for the preservation of the species involved and analyzed in the study.

Acaricidal activity of Amburana cearensis on the cattle tick Rhipicephalus (Boophilus) microplus / Atividade acaricida de Amburana cearensis frente ao Rhipicephalus (Boophilus) microplus

ABSTRACT: This experiment was carried out to study the bioacaricidal activity of Amburana cearensis against engorged females of Rhipicephalus (Boophilus) microplus. The crude ethanolic extract from the leaves of A. cearensis was submitted to partition with organic solvents (hexane, chloroform and ethyl acetate) in order of increasing polarity; and evaluated using three treatments at concentrations of 5, 10 and 25mg ml-1. To evaluate the acaricidal activity, engorged females were submitted to the adult immersion test. Parameters analyzed were the weight of females; weight of egg mass; percentage of hatch; reproductive efficiency; expected rate of reproduction; and efficacy. For each extract and concentrating fraction, tests were performed in triplicate. Among all fractions, the hexane (2.5%) achieved the best results in all parameters analyzed: 52.7% of inhibition of oviposition; 39% of hatching rate; 3,271 index of reproductive efficiency; and 67.0% effectiveness. The extract obtained gradual dose response with increasing concentration; and could be used as an aid in the control of R. (B.) microplus therapy.

RESUMO: O objetivo deste estudo foi avaliar a atividade acaricida in vitro de Amburana cearensis contra fêmeas ingurgitadas de Rhipicephalus (Boophilus) microplus. O extrato etanólico bruto das folhas de A. cearensis foi submetido à partição com solventes orgânicos (hexano, clorofórmio e acetato de etila) em ordem crescente de polaridade. Foram realizadas três diluições, nas concentrações de 5, 10 e 25mg ml-1. Para avaliar a atividade carrapaticida, fêmeas teleóginas foram submetidas ao teste de imersão de fêmeas ingurgitadas. Os parâmetros analisados foram peso das fêmeas, peso da massa de ovos, porcentagem de eclosão, eficiência reprodutiva, índice de reprodução esperada e eficácia. Para cada extrato, fração e concentração, os testes foram realizados em triplicata. Dentre as frações, a hexânica (2,5%) apresentou os melhores resultados para todos os parâmetros analisados, alcançando 52,7% de inibição da oviposição; 39,0% de porcentagem de eclosão; 3.271 de índice de eficiência reprodutiva; e 67% de eficácia. O extrato obteve uma dose resposta gradual com o aumento da concentração; podendo ser utilizado como terapia auxiliar no controle do R. (B.) microplus.

The role of flavonoids on oxidative stress in epilepsy.

BACKGROUNDS: Oxidative stress can result from excessive free-radical production and it is likely implicated as a possible mechanism involved in the initiation and progression of epileptogenesis. Flavonoids can protect the brain from oxidative stress. In the central nervous system (CNS) several flavonoids bind to the benzodiazepine site on the GABAA-receptor resulting in anticonvulsive effects. OBJECTIVE: This review provides an overview about the role of flavonoids in oxidative stress in epilepsy. The mechanism of action of flavonoids and its relation to the chemical structure is also discussed. RESULTS/CONCLUSIONS: There is evidence that suggests that flavonoids have potential for neuroprotection in epilepsy.