Contaminação de produtos de higiene e cosméticos por n-nitrosaminas

N-nitrosamines are carcinogenic compounds that have been found during the last three decades in a variety of consumer products, including cosmetic and personal care products, and their raw materials. These compounds are formed from amine precursors and nitrosating agents present in the formulations. This paper reviews the formation and occurrence of N-nitrosamines in cosmetic products, as well as presents considerations about analytical, toxicological and regulatory aspects.

Composição química dos componentes voláteis de Capsicodendron dinisii Schwancke (Canellaceae)

The volatile components of the stem bark of Capsicodendron dinisii were obtained by hydrodistillation using a modified Clevenger-type apparatus. The chemical compounds were identified using the arithmetic index and confirmed by GC-MS. Twenty-three compounds suggest the identified representing almost 90% of the total oil composition. Limonene (68.5%) was the major compound found. The stereochemistry of limonene was determined and was found to be represented by (+)-limonene (94%) and (-)-limonene (6%). The presence of drimenol (0.7%), a drimane sesquiterpenoid, confirmed the volatile components characteristics of the Canellaceae family.

Estudo da eficiência de degradação de tetracloreto de carbono por plasma térmico e caracterização dos produtos formados

Decomposition of carbon tetrachloride in a DC thermal plasma reactor was investigated in argon atmosphere. The operational parameters such as plasma torch power and argon flow rate versus CCl4 conversion were examined. The CCl4 net degradation was determined by GC-FID, the chlorine produced was quantified by iodometric titration, the solid carbon was characterised by Raman spectroscopy and by BET analysis. The solid carbon collected inside de plasma reactor was submitted to solid/liquid extraction and the desorbed species were identified by GC-MS.

Uso de CLAE no controle de qualidade em produtos comerciais de Nim: reprodutibilidade da ação inseticida

The Neem tree, Azadirachta indica, provides many useful compounds that are used as pesticides. However, the efficiency in field of products like neem oil can be committed because they have not been observed reproductive content of secondary metabolic like azadirachtin. Based on reverse-phase high-performance liquid chromatography (HPLC) a new method was developed to permit the rapid quantitative analysis of azadirachtin from seeds, extracts and oil of Neem. In the present study it was evaluated the azadirachtin quantitative variation among various Neem's extracts and seeds showing the importance of quality control for reproduction of the insecticide efficiency, using S. frugiperda as target insect.

Análise por componentes principais de espectros nexafs na especiação do molibdênio em catalisadores de hidrotratamento

Bulk and supported molybdenum based catalysts, modified by nickel, phosphorous or tungsten were studied by NEXAFS spectroscopy at the Mo L III and L II edges. The techniques of principal component analysis (PCA) together with a linear combination analysis (LCA) allowed the detection and quantification of molybdenum atoms in two different coordination states in the oxide form of the catalysts, namely tetrahedral and octahedral coordination.

Projeto e construção de um picnômetro a ar para caracterização de insumos e produtos farmacêuticos

This paper describes a project, construction and test of a low cost air pycnometer, developed to be used preferentially in pharmaceutical research. A complete discussion of the construction, test and calibration of this equipment is presented and some measurements are made using pharmaceutical powders and dry granulations. The equipment performance has been estimated through its calibration curve, and the obtained value to its volume resolution is about 1%. This equipment is accomplished at the Applied Nuclear Physics Laboratory of University of Sorocaba (LAFINAU) in Sorocaba, SP, Brazil and it was denominated "Picnômetro a Ar Uniso - PICNAU".

Variação anual do rendimento e composição química dos componentes voláteis da Siparuna guianensis Aublet

This work describes the volatile composition obtained by hidrodistillation of fresh leaves of Siparuna guianensis Aublet collected from Cuiabá (MT), Brazil. The composition of DCM extract of hydrolate was determined by GC-MS analysis and the results showed that the specie present a range of components according to their phenology and period of the leaves were collects. The highest volatile components yield was obtained during the reproductive period and the principal compound was the siparunone.

Classificação periódica: um exemplo didático para ensinar análise de componentes principais

A dataset of chemical properties of the elements is used herein to introduce principal components analysis (PCA). The focus in this article is to verify the classification of the elements within the periodic table. The reclassification of the semimetals as metals or nonmetals emerges naturally from PCA and agrees with the current SBQ/IUPAC periodic table. Dataset construction, basic preprocessing, loading and score plots, and interpretation have been emphasized. This activity can be carried out even when students with distinct levels of formation are together in the same learning environment.

HIV: mecanismo de replicação, alvos farmacológicos e inibição por produtos derivados de plantas

The AIDS epidemy has spread out and led to the diversification on the research for new antiviral drugs. Natural products, especially those derived from plants, are well-recognized as excellent sources of new drugs. Several of them have inhibitory activity against HIV replication, and some have been already clinically tested, with favorable results. This review presents the biochemical basis of the viral cycle and the research up to date on the identification, determination of the mechanism of biological action together with the therapeutical potential of plants-derived natural products, in the inhibition of HIV.

Identificação de adulteração de biocombustível por adição de óleo residual ao diesel por espectrofluorimetria total 3D e análise das componentes principais

Total spectrofluorimetry associated to Principal Components Analysis (PCA) were used to classify into different groups the samples of diesel oil, biodiesel, vegetal oil and residual oil, as well as, to identify addition of non-transesterified residual vegetable oil, instead of biodiesel, to the diesel oil. Using this method, the samples of diesel oil, mixtures of biodiesel in diesel and mixtures of residual oil in diesel were separated into well-defined groups.

Discriminação entre estádios de maturação e tipos de processamento de pós-colheita de cafés arábica por microextração em fase sólida e análise de componentes principais

A fruit chemical composition reflects its maturation stage. For coffee, it is also the reflex of the post-harvesting processing type, dry, semi-wet and wet. The object of this work was to verify if headspace solid phase microextraction coupled to gas chromatography (HS-SPME-GC) could be used to discriminate between samples harvested in different maturation stages and treated by different processes. With application of principal component analysis to the area of 117 compounds extracted by SPME, using divinylbenzene/Carboxen/polydimethylsiloxane fiber, it was possible to discriminate, in the roasted and ground coffee, the maturity stage and processing type used .

A gestão do conhecimento aplicada à reciclagem de componentes automotivos através do tratamento das informações contidas em documentos de patentes

This article evaluates the technologies adopted for recycling and reuse of automobile components, through the analysis of patents documents. The automobile batteries recycling is the main topic, followed by the automatic disassembly of vehicles, tires recycling and polyurethane recycling. None document approached recycling of steel and aluminum or ceramics products. The reduced number of technologies for the recycling of the polymeric compounds (including polyurethane) indicates that a bigger number of research and inventions must be elaborated in the next years, aiming at to the reduction of costs of processes and adequacy to the more restricted environmental legislation.

Desenvolvimento e validação de método analítico para determinação de benzoato, sorbato, metil e propilparabenos em produtos alimentícios utilizando a eletroforese capilar

In this work, a rapid and simple method using capillary electrophoresis (CE) was developed for the determination of the benzoate, sorbate, methyl and propylparaben in foodstuffs. A running buffer consisting of 20 mmol L-1 (pH = 9.3) tetraborate enabled separation of the analytes in less than 5 min. The detector wavelength was set at 220 nm. The method was successfully applied to the analysis of sodas, sweeteners, sauces and juices. The range of preservatives found were from 478.5-466.6 mg kg-1 for methylparaben , 83.7-231.3 mg kg-1 for sorbate and 336.7-428.3 mg kg-1 for benzoate.

Do engenho à biorrefinaria: a usina de açúcar como empreendimento industrial para a geração de produtos bioquímicos e biocombustíveis

A sugar cane mill is at the present moment a modest biorefinery producing few products such as sugar, ethanol and polyhydroxybutyrate (PHB). In the near future, this mill can expand its production using several renewable feedstock's to produce biofuels and high value biobased chemicals. However, the choice of appropriate products for addition to the portfolio is challenged by a lack of broad-based conversion technology coupled with a plethora of potential targets. The intent of this revision was to catalyze research efforts to expand the list of products and to present an updated evaluation of potential target structures for chemical production.

Definição de shelf life para produtos químicos: a importância de um guia de estabilidade específico para o segmento

The chemical industries worldwide are passing through a very particular moment of re-adaptation due to the implementation of an European regulation called, Registration, Evaluation, Authorization and Restriction of Chemicals (REACH). In Brazil, the Brazilian Chemical Industry needs urgently a specific guide of chemical products stability. The main purpose of this work is to present a proposal of a guide of stability for chemical products based on the reference guides of the International Conference on Harmonization (ICH). Thus, this work proposes an innovation in terms of methodology which will be useful for shelf life definition purpose for chemical industry products.