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The Catalogue Raisonne of Cândido Portinari, published in 2004, is the product of the inventory of the work of this artist, carried out as part of the Portinari Project. The Portinari Project is coordinated by the painter's only son, Joao Candido Portinari. The Catalogue is the first of its kind to be published in Latin America and it became an example and encouraged the development of similar projects about other Brazilian and Latin American artists. The reading of the work of Portinari, as presented by the Catalogue Raisonne, is focused on historical aspects, formal and stylistic documentation. It does not have a detailed study of the materials and techniques used by the artist. This work aims to contribute to the knowledge of Portinari's work, in terms of its stylistic influences, his painting materials and techniques. Through the methods of art technological source research and scientific analysis of 15 works of the artist, especially the mural paints Guerra e Paz (War and Peace), the present work complements substantially the extensive work already published in the Catalogue Raisonne of Candido Portinari.

Seeds of native species from the rain forest (Amazon) are source of chitinases and their protein extracts exhibited strong and broad antifungal activity. Numerous plant species native to the Amazon have not yet been chemically studied. Studies of seeds are scarcer, since adversities in accessing study areas and seasonality pose constant hurdles to systematic research. In this study, proteins were extracted from seeds belonging to endemic Amazon species and were investigated for the first time. Proteolytic activity, peptidase inhibitors, and chitinases were identified, but chitinolytic activity predominated. Four proteins were purified through chromatography and identified as lectin and chitinases by MS/MS analyses. The proteins were examined for inhibition of a phytopathogen (Fusarium oxysporum). Analyses by fluorescence microscopy suggested binding of propidium iodide to DNA of fungal spores, revealing that spore integrity was lost when accessed by the proteins. Further structural and functional analyses of defensive proteins belonging to species facing highly complex ecosystems such as Amazonia should be conducted, since these could provide new insights into specificity and synergism involving defense proteins of plants submitted to a very complex ecosystem.

Gas chromatography has long been used as a means of identifying proteins in acid hydrolysates of paints and adhesives on the basis of their amino acid composition. Existing procedures for amino acid derivatization can, however, take up to 4 hours per analysis, whereas a new procedure employed at the Getty Conservation Institute can be carried out in less than 20 minutes. This procedure involves the formation of N(O,S)-ethoxycarbonyl ethyl esters of amino acids using ethyl chloroformate and then a separation on an HP-INNOWAX capillary column. This procedure was employed to analyze samples from the binding media library at the Getty Conservation Institute, and amino acid compositions were tabulated for various proteins that could be used for identification purposes.

Polyester resins have been commonly used in art conservation for embedding paint cross sections prior to microscopic and analytical studies. These resins set rapidly without heat, are clear, polish readily, and microtome easily. While they work well for embedding most paint samples, they pose pro blems for some specific samples. The polyester embedding media have been found to dissolve wax, some organic colorants, and fresh natural resin layers in cross sections. The embedding resin also wicks into porous samples of low binder content. At times, infiltration can be desirable for its consolidating effects, but it can also interfere with the determination of the type of binder in the sample by producing blotchy, uneven staining results and by obstructing infrared analysis. Alternate embedding materials and procedures are discussed in this paper. One method to prevent the infiltration of embedding media is presented in which the samples are precoated with a thixotropic acrylic gel before embedding. O...

Traditional Western techniques for gilding of polychromed sculptures and panel paintings include the use of grounds prepared by the application of a first layer of gesso grosso followed by a gesso sottile layer, as described by Cennino Cennini in his treatise on painting techniques. These techniques have been used in Italy since the Middle Ages, and were later adopted by many artists in regions of the new world under Spanish and Portuguese rule, sometimes with local variations in materials and techniques. This article discusses the use of Fourier transform infrared spectrometry (FTIR) for the identification of inorganic materials present in the grounds of Baroque wooden polychromed sculptures from Minas Gerais, Brazil. This technique allows the quantitative analysis of the separate layers of the grounds, with respect to the anhydrite/gypsum ratio present in the sample. The technique has several advantages over the one currently used (Debye-Scherrer chamber for x-ray powder diffraction). FTIR spectra can be obtained in a few minutes allowing quantitative results, while x-ray diffraction usually takes more time and does not give accurate data for quantitative studies. The article also discusses the results of the studies of the grounds in Brazilian polychromed sculptures and compares the original Italian technique with Portuguese and Spanish techniques and its variations in Brazil. -- AATA