<p>Phytochemical investigation of the MeOH extract of Schinopsis brasiliensis Engl. stems led to the isolation of the new biflavanone (2R*,3R*,2''R*,3''R*)-7-hydroxy-4'-methoxy-flavanone- (3→3'')-3''',7''-dihydroxy-4'''-methoxy-flavanone and 4,2',4'-trihydroxychalcone-(3→O→4'')- 2''',4'''-dihydroxychalcone, whereas methyl gallate, gallic acid, (6R,9R)-megastigma-4-en-3-one- 9-O-β-glucopyranoside, quercetin-3-O-β-D-xylopyranoside and tricetin-3'-O-β-D-glucopyranoside were isolated from the MeOH extract of leaves. Their chemical structures were elucidated using spectroscopic methods and comparison with the literature data. Both biflavonoids showed weak inhibition activities of acetyl and butyrylcholinesterase enzymes when compared with eserine.</p>

A atmosfera de regiões costeiras adjacentes a regiões urbanas podem ser afetadas pela emissão de diferentes poluentes atmosféricos, dentre eles, os íons majoritários. Nesse estudo foram estudadas a composição química e as fontes de carboxilatos e íons solúveis em água em partículas finas e grossas bem como as estimativas de fluxo de deposição seca em um sítio em uma região costeira tropical afetada por uma Região Metropolitana. As concentrações médias de carboxilatos totais foram 78 ng m–3 na fração fina e 81 ng m–3na fração grossa do material particulado (MP). Os valores correspondentes de concentração para os íons inorgânicos foram 2143 ng m–3 e 4880 ng m–3, respectivamente, para as frações fina e grossa. As principais fontes para as partículas finas foram: (i)formação fotoquímica de ácidos carboxílicos na fase vapor e posterior conversão gás-partícula sobre partículas de sal marinho, (ii) emissões de fontes antrópicas envolvendo processos de transporte de longas distâncias; e(iii) a interconversão de espécies voláteis entre fases atmosféricas. Por sua vez, as fontes predominantes para as partículas grossas foram:(i) espécies gasosas ab/adsorvidas em partículas pré-existentes, (ii)emissão primária de partículas grossas de fontes antrópicas, e (iii) spray marinho e/ou ressuspensão do solo. Finalmente, a deposição seca de partículas representa o fluxo de íons majoritários na interface ar-oceano.

The coastal atmosphere adjacent to large urban areas can be strongly affected by the emission of air pollutants, among them, major ions species. In this study, the chemical composition and sources of carboxylates and other water-soluble ions in fine and coarse aerosols as well as estimates of particle dry deposition fluxes were studied at a tropical coastal site affected by an urban environment. The mean concentrations of the total carboxylates were 78 ng m–3 in fine fraction and 81 ng m–3 in coarse fraction of particulate matter (PM). The corresponding values for the total inorganic ions were 2143 ng m–3 and 4880 ng m–3 respectively. Main sources for fine particles were:(i) photochemical formation of carboxylic acids in vapor phase and a posterior gas-to-particle conversion onto sea salt particles; (ii) emissions from anthropic sources with long range transportation processes; and (iii) the interchanging of volatile species among atmospheric phases. In turn, for coarse particles, the predominant sources were: (i)gas-phase species and ab/adsorbed onto pre-existing particles afterwards;(ii) primary emission of coarse particles from anthropogenic sources; and (iii) sea salt spray and/or soil resuspension. Finally, particle dry deposition was a very important mechanism representing air-to-sea fluxes of major species.