Five flavanones and three chalcones were isolated from Campomanesia adamantium Berg. (Myrtaceae) leaves. The contents of these compounds were determined by HPLC. The phenolic contents were also determined. The monitoring of the antioxidant activity was carried out by inhibition of peroxidation using the linoleic acid system and radical-scavenging (DPPH). The plants were collected from 4 distinct cities of the Mato Grosso do Sul State, Brazil. The different samples exhibited a range of 4.67-232.35 mg/g chalcones and 15.62-50.71 mg/g flavanones and phenolic contents of the 7.24-21.19 mg/g gallic acid. All extracts showed high antioxidant activity with a wide range of the radical-scavenging (DPPH) from 52.0 to 92.2 % and inhibition oxidation of linoleic acid from 14.6 to 94.2%.

RESUMO:Campomanesia adamantium (Cambess.) O. Berg, Myrtaceae, é uma espécie nativa. As folhas são utilizadas na medicina popular. Os extratos hexânico e acetato de etila das folhas mostraram pouca variação na sua composição química em diferentes estações do ano associado com o desenvolvimento do vegetal, enquanto o extrato etanólico mostrou alteração significativa em relação à composição química. Todos os extratos etanólicos mostraram alta atividade antioxidante frente ao método DPPH e de moderada a alta para β-caroteno/ácido linoléico.Unitermos: Campomanesia adamantium, guavira, guabiroba, sazonal ABSTRACT: "The Influence of seasonal variation in levels of flavonoids and antioxidant activity of the leaves of Campomanesia adamantium". Campomanesia adamantium (Cambess.) O. Berg, Myrtaceae, is a native species. The extracts of ethyl acetate and hexane showed little variation in their chemical composition at different seasons of the year associated with the development of the plant, while the ethanol extract showed significant change in relationship to chemical composition. All ethanol extracts showed high antioxidant activity against DPPH method and from moderate to high antioxidant activity for β-carotene/linoleic acid.

Postal 351, RESUMO: O objetivo desta pesquisa visou a avaliação do perfil cromatográfico, a atividade antioxidante, e os teores de fenóis e flavonóides nos extratos orgânicos e infusos de folhas das espécies C. xanthocarpa e C. sessiliflora coletadas durante os períodos vegetativo e reprodutivo. As análises dos extratos e infusos foram realizadas empregando-se cromatografia líquida de alta eficiência com detector de arranjo de diodos (CLAE-DAD). Segundo a comparação dos perfis obtidos foi baixa a similaridade entre a composição química das duas espécies. O teor de fenóis (64,69-334,18 mg de ácido gálico mL -1 ) foi superior ao teor de flavonóides (4,02-35,60 mg de quercetina mL -1 ) em todas as análises. Os extratos orgânicos e infusos das folhas coletadas no período reprodutivo apresentaram teores de fenóis e de flavonóides superiores em ambas as espécies. Não houve uma correlação linear entre o teor de fenóis e flavonóides com a atividade antioxidante em todas as amostras. Palavras-chave:Campomanesia sessiliflora, Campomanesia xanthocarpa, CLAE-DAD, guavira, guabiroba ABSTRACT: Evaluation of the chromatographic profile and the antioxidant activity of the species Campomanesia sessiliflora (O. Berg) Mattos and Campomanesia xanthocarpa O. Berg. The aim of this study was to evaluate the chromatographic profile, the antioxidant activity, and the levels of phenols and flavonoids in organic extracts and infusions from leaves of the species C. xanthocarpa and C. sessiliflora collected during the vegetative and reproductive periods. Analyses of the extracts and infusions were performed by adopting high-performance liquid chromatography with diode array detector (HPLC-DAD). Based on the comparison of the obtained profiles, similarity between the chemical composition of the two species was low. Phenol levels (64.69-334.18 mg gallic acid mL -1 ) were superior to the level of flavonoids (4.02-35.60 mg quercetin mL -1 ) in all analyses. Organic extracts and infusions from leaves collected in the reproductive period had superior phenol and flavonoid levels in both species. There was not a linear correlation of phenol and flavonoid levels with antioxidant activity in all samples.

A headspace solid-phase microextraction (HS-SPME) procedure that employs a PDMS/DVB fiber was developed for the analysis of gas-phase polycyclic aromatic hydrocarbons (PAHs) collected in polyurethane foam (PUF) by gas chromatography (GC) mass spectrometry. The method exhibited good linearity (R (2) > 0.99) and repeatability (4.9-25 %) as well as an impressive detection limit that ranged from 1.1 to 3.3 ng. Twenty-two air samples were collected by high-volume samplers from January to November 2007 in a semiurban area of Dourados (Brazil) and were analyzed for their content of total suspended particulates and PAHs. The PAHs were extracted from the PUF samples using the developed procedure (HS-SPME), and PAHs adsorbed on particulate matter were extracted with dichloromethane/methanol (4:1 [v/v]) in an ultrasonic bath. The values of the total daily concentrations of 16 PAHs determined in the samples ranged from 0.375 to 8.407 ng m(-3). In addition, diagnostic ratios were calculated, showing that the PAHs in the atmosphere at the sampling site originated predominantly from vehicle emissions and the combustion of grass and wood. Hierarchical cluster analysis and principal component analysis were performed as well, the results of which indicated (1) the same sources of PAH identified by the diagnostic ratios and (2) that the sampling days could be categorized into three groups depending on the atmospheric conditions. GC retention indices were also used to identify PAHs, biphenyl (phenylbenzene), and heterocyclic organic compounds (benzofurans) in some of the samples.

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