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Four new clerodane diterpenes, casearupestrins A-D (1-4), were isolated from the leaves of Casearia rupestris. Compounds 1 and 4 were acetylated to yield 2,7-di-O-acetylcasearupestrin A (5) and 2,6-di-O-acetylcasearupestrin D (6). All compounds were evaluated for cytotoxicity against a small panel of human cancer cell lines. Casearupestrin A (1) exhibited the most potent activity against MDA/MB-435 (human melanoma) and SF-295 (human glioblastoma) cells, superior to that of the standard drug doxorubicin.

Coffee is globally one of the most widely used food products and is vital to the economies of countries involved in its production and export. Due to its commercial importance, the detection of impurities and foreign matters has been a constant concern in fraud verification, especially because it is difficult to perceive adulterations with the naked eye in samples of roasted and ground coffee. Until now, there has been no comprehensive methodology for identification of the many types of coffee adulterants. This work describes, for the first time, a fast and effective technique using 1 H NMR to check for adulteration in roasted coffee. The samples used were a set of commercial Brazilian arabica blends produced from good cup quality beans, and four adulterants (corn, coffee husks, barley, and soybean). The methodology was effective for all the adulterants analyzed in 31 commercial samples.Published by Elsevier Inc.

With globalization, it has become necessary to adopt policies to regulate the coffee market, addressing problems including the authenticity and traceability of products. It is therefore important to establish methodologies that can help to safeguard the interests of producer countries and add value to products. For this purpose, the use of NMR combined with multivariate statistical procedures can be an attractive option. The aim of this study was to develop a fast and effective technique, using H NMR coupled with multivariate statistics, to create a fingerprint of roasted coffees, distinguishing them according to the main Brazilian producer regions. Several compounds suitable for differentiating roasted coffees were identified in the fingerprint. Discriminant analysis revealed good distinction among the samples. The compounds catechol, trigonelline, caffeine, and-methylpyridine were most important for the differentiation. The findings should assist coffee-producing countries in adopting measures to protect their markets and to add value to coffee products.

The degradation of a reactive blue 4 dye in acidic solution has been compared using electrochemical reduction and oxidation at reticulated vitreous carbon electrode (RVC) and Ti/SnO 2 /SbO x (3%mol)/RuO 2 (30%mol) electrodes and photo-Fenton method under UV irradiation. The reduction of RB4 dye at-0.6 V on RVC electrode results in 50% of color removal and up to 64% of TOC removal. The direct oxidation of RB4 dye at +1 V on RVC promotes only the oxidation of amine group and there is no color removal. On SnO 2 electrode, 58% TOC was removed and the decolorization is around 100 % after 1 hour of electrolysis at 2.4 V indicating good efficiency. Best performance was obtained by photo-Fenton method that indicates 80% elimination of TOC and 100% of color removal but the method requires oxidant addition and time of rest to remove the generated residues.

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A remoção do corante reativo Reactive Blue 4 (RB4) por redução eletroquímica em solução aquosa foi investigada sobre eletrodo de carbono vítreo reticulado. O grupo antraquinona presente no corante RB4 é reduzido em pH < 8,0 em uma única etapa a hidroquinona, segundo um processo reversível de dois elétrons e reação de pré-protonação, via geração de um radical semiquinona detectado espectrotométricamente. Em pH > 8,0, ambas as formas não e pré-protonada da antraquinona são reduzidas em duas etapas reversíveis de dois elétrons. Após 3 horas de eletrólise em meio ácido e neutro o corante perde 60% de sua coloração, enquanto que em meio alcalino perde apenas 37%. Simultaneamente, 64% de remoção de carbono orgânico total foi obtida após eletrólise em meio ácido de pH 2,0.The electrochemistry reduction for the removal of Reactive Blue 4 (RB4) dye from aqueous solution using reticulated glassy carbon electrode is investigated. At pH < 8.0 the anthraquinone group of the RB4 dye are reduced in one cathodic step to hidroquinone after a reversible two-electron process involving a precedent two protons reaction. A stable semiquinone is detected by spectrophotometric technique. At pH > 8.0 the reduction process involves two reversible 2-electron steps, whose species are generated by a protonation equilibrium of anthraquinone group. The results shows that 60% of color removal was obtained after 3 hours of RB4 dye electrolysis at acidic and neutral conditions and only 37% at alkaline conditions. Simultaneously 64% of total organic carbon was removed after electrolysis at pH 2.0.Keywords: reactive dyes, electrochemical reduction, dye treatment, reactive blue 4 IntroductionReactive dyes are the main group of dyes used in the textile industry.1 They are very effective in fabric dyeing due to the reactive groups capable of forming covalent bonds with a hydroxyl or amino group on the fiber. Inefficiencies in the dyeing process results in 10-15% of all dyestuff being lost directly to wastewater.2 Therefore, their crescent world consumption has attracted the critical attention of the public and the authorities with respect to the toxicological and environmental aspects of the reactive dyes. 3,4 Dye wastewater is usually treated by physical or chemical treatment process. They include physicalchemical flocculation, electroflotation, membranefiltration, electrokinetic coagulation, ion-exchange, irradiation, precipitation and other treatment using activated carbon. 5 Over the past few years, alternative methods 6-10 for dye treatment have been investigated, including chemical oxidation with reagents such as: ozone, hydrogen peroxide, ozone/UV, hydrogen peroxide/UV and Fenton's reagent [hydrogen peroxide + Fe (II)]. The application of electrochemical oxidation with or without UV light as method for dye degradation have also been investigated, [11][12][13][14][15] but no mechanisms of the reduction were discussed. [16][17][18][19] Most of the electrochemical studies involving reduction of reactive dyes are based on mercury electrode [16][17...