Comportamento de cristalização de lipídios estruturados obtidos a partir de gordura de palmiste e óleo de peixe

The aim of this study is to evaluate the crystal structure of binary mixtures of palm kernel fat and fish oil, before and after chemical and enzymatic interesterification. The crystal structure was analyzed by polarized light microscopy. The addition of fish oil didn't change the palm kernel fat crystallization characteristics, spherullites of types A and B being observed. However, due to chemical and enzymatic interesterification, smaller crystals were obtained. There was no difference between chemical and enzymatic interesterification, probably as a function of acyl migration in discontinuous processes catalyzed by lipases.

Importância do metabolismo no planejamento de fármacos

It is widely recognized that pharmacokinetic optimization needs to be addressed early in drug discovery to reduce the high failure rate in bringing drugs to market. Poor absorption, too short duration of action due to high elimination rate, or the presence of active metabolites are examples of properties that can potentially lead to unsuccessful clinical programmes. Here I describe a brief overview of advantages and molecular strategies for improving metabolic and pharmacokinetic properties applied to the discovery of fluconazol, beta-blockers, ritonavir and ezetimibe and to the development of the prodrugs enalapril and bambuterol.

Lipídios estruturados obtidos a partir da mistura de gordura de frango, sua estearina e triacilgliceróis de cadeia média: I- Composição em ácidos graxos e em triacilgliceróis

The purpose of this study is to analyze the interactions that occur in binary and ternary fat blends between medium and long chain triacylglycerols and their structured lipids obtained by chemical interesterification through the analysis of their physico-chemical properties. The synthesized structured triacylglycerols presented from 14.8 to 58.4% medium chain fatty acids, from 15.7 to 37.2% saturated fatty acids, from 19.2 to 47.5% monounsaturated fatty acids, and from 6.7 to 15.2% essential fatty acids. Chemical interesterification modified the behavior of binary and ternary mixtures and new types of triacylglycerol groups were formed.

Lipídios estruturados obtidos a partir da mistura de gordura de frango, sua estearina e triacilgliceróis de cadeia média: II- pontos de amolecimento e fusão

The aim of the present work is to investigate the effects of blending and chemical interesterification reactions on the softening and melting behavior of chicken fat, its stearin and medium chain triacylglycerols, and blends thereof in various ratios. Chemical interesterification is a promising alternative to the current processes of modifying the physical properties of fats. In the experimental design 7 samples corresponding to 7 different blend proportions were used. The results were represented in triangular diagrams. The addition of stearin influenced the softening and melting points. The mixture response surface methodology proved to be an extremely useful tool for the optimization of the fat mixtures.

Comportamento de cristalização de lipídios estruturados por interesterificação química de banha e óleo de soja

The aim of this study was to evaluate the crystallization behavior of binary mixtures of lard and soybean oil in different ratios and their respective structured lipids obtained by chemical interesterification. Crystallization kinetics and polarized light microscopy were used to analyze the mixtures before and after interesterification. The addition of soybean oil changed the lard crystallization, by the effect of the dilution. Crystal diameter increased, while the number of crystals decreased, as a function of temperature. Interesterification resulted in the formation of fewer crystals, with larger diameter in comparison with the original mixtures.

Lipídios modificados obtidos a partir de gordura do leite, óleo de girassol e ésteres de fitosteróis para aplicação em spreads

The objective of this paper was to evaluate the modifications in milkfat properties with the addition of sunflower oil (SO) and phytosterol esters (PE) and chemical interesterification. Fatty acid composition, softening point and consistency were determined. The saturation degree of milkfat decreased with the addition of SO and PE. Consequently, milkfat presented lower softening point and consistency. Chemical interesterification caused an increase in softening point due to the formation of higher amounts of trissaturated triacylglycerols with rearrangement. The incorporation of unsaturated fatty acids from SO and PE by milkfat triacylglycerols after chemical reaction caused linearization of consistency curves.

Territorio y sostenibilidad : diagnosis del metabolismo social de Amorebieta-Etxano : con los pies en el suelo

Postprint (published version)

Lipídios estruturados: alternativa para a produção de sucedâneos da gordura do leite humano

Human milk has characteristics of great importance for the newborn. Its composition shows all nutrients in quantity and quality needed, in addition to providing protection against infections and allergies and stimulating the immune system. Therefore, the composition of fatty acids and their distribution in the triacylglycerols are targets of studies on infant formula, and the triacylglycerols of human milk fat should serve as a model for the lipid components. This review aims to report studies of technology in lipids in order to produce structured lipids as substitutes of human milk fat.

Lipídios como indicadores de fontes e distribuição de matéria orgânica particulada em um complexo estuarino-lagunar tropical (Mundaú-Manguaba, AL)

Fatty acids, alcohols and sterols were considered as markers of the source and distribution of particulate organic matter during the dry season in the Mundaú-Manguaba estuarine-lagoon system, NE Brazil. Lipid composition showed an overwhelming influence of autochthonous sources of organic matter in all system´s compartments, including the probable occurrence of algal blooms in specific areas. On the other hand, contamination by sewage was restricted to Mundaú lagoon. This scenario differed from known conditions observed in the wet season, illustrating the usefulness of the lipid biomarker approach for the characterization of other complex and dynamic systems in the Brazilian coastal zone.

Metabolismo, oxidação e implicações biológicas do ácido docosahexaenoico em doenças neurodegenerativas

Docosahexaenoic acid (C22:6, n-3, DHA) is a polyunsaturated fatty acid (PUFA) present in large concentrations in the brain and, due to the presence of six double bonds in its structure, is highly susceptible to oxidation by enzymes and reactive oxygen/nitrogen species. The peroxidation of PUFAs has been implicated in an increasing number of human disorders, including neurodegenerative diseases. Hence, a better understanding of the metabolism pathways of DHA should provide new insights about its role in neurodegenerative diseases. Here we review the main aspects related to DHA metabolism, as well as, the recent findings showing its association with neurodegenerative diseases.

Nanopartículas de lipídios sólidos: métodos clássicos de produção laboratorial

Solid lipid nanoparticles have been extensively investigated as drug delivery systems. These colloidal systems have major advantages compared to others more traditional. Reported advantages include sustained release, ability to solubilize lipophilic drugs, increased physical and chemical stability of labile molecules, decreased unwanted side-effects showing lower toxicity, and scale up facilities. This paper aims at reviewing the traditional methods of solid lipid nanoparticles production, such as fusion-emulsification (hot and cold), solvent evaporation-emulsification and microemulsion, dealing with the main technological parameters that influence the quality properties of solid lipid nanoparticles.

Uso de aditivos na biodegradação de madeira pelo fungo Ceriporiopsis subvermispora: efeito na peroxidação de lipídios dependente de manganês-peroxidase

Ceriporiopsis subvermispora is a selective fungus in the wood delignification and the most promising in biopulping. Through the lipid peroxidation initiated by manganese peroxidase (MnP), free radicals can be generated, which can act in the degradation of lignin nonphenolic structures. This work evaluated the prooxidant activity (based in lipid peroxidation) of enzymatic extracts from wood biodegradation by this fungus in cultures containing exogenous calcium, oxalic acid or soybean oil. It was observed that MnP significant activity is required to promote lipid peroxidation and wood delignification. Positive correlation between prooxidant activity x MnP was observed up to 300 IU kg-1 of wood.

ARSÊNIO E ARROZ: TOXICIDADE, METABOLISMO E SEGURANÇA ALIMENTAR

Arsenic is considered a semimetal, and its wide distribution in the Earth's crust in different chemical forms, including organic and inorganic species, has a great deal of influence on the mechanisms of toxicity. Exposure to arsenic can be either through occupational practice (use of pesticides) or by the consumption of water and food containing the element. Rice is considered a fundamental constituent of the basic diet of Brazilians and is usually cultivated in flooded conditions. Such a plantation system results in an increased amount of As in the soil and hence a greater accumulation of As in the plant, which is highlighted by the inorganic species' classification as highly toxic. Besides the use of mitigation techniques to reduce the toxicological risk, monitoring the concentration of As and its chemical species in rice and rice products is required through the establishment of legislation in the area. Thus, some world organizations are conducting improved research to determine and establish acceptable concentrations of As and its chemical species in rice, e. g., in 2012, FDA researchers described a chemical speciation methodology for As in rice and rice products. Hence, the application of existing chemical speciation methods and the establishment of parameters for ensuring food security and exposure risk assessment deserve particular consideration.

Efeito do Soil-borne wheat mosaic virus sobre o metabolismo de cinco genótipos de trigo com diferentes níveis de resistência à doença

Com o objetivo de conhecer as alterações metabólicas promovidas pelo Soil-borne wheat mosaic virus (SBWMV), um dos vírus economicamente mais importantes da cultura do trigo (Triticum aestivum), foram analisados os níveis de proteínas solúveis e determinadas as atividades da peroxidase e da protease em quatro cultivares (BRS Guabiju, BRS 194, BRS 179, BR 23) e uma linhagem (PF 980524) de trigo com diferentes níveis de resistência ao vírus. Os dados obtidos foram submetidos à análise de variância, comparando-se as médias, pelo Teste de Duncan a 5%. Os níveis de proteínas solúveis foram mais elevados nas plantas sem sintomas, enquanto que as atividades da peroxidase e da protease foram maiores em plantas com sintoma de mosaico do que em plantas assintomáticas. Além disso, pode-se constatar que quanto maior a suscetibilidade do genótipo, maior o nível de atividade da protease. Estes resultados são promissores para estudos de inibição da protease para controle de viroses.

Alterações no metabolismo de cinco genótipos de trigo com diferentes níveis de resistência ao Soil-borne wheat mosaic virus

Soil-borne wheat mosaic virus - SBWMV, agente causal da virose que se caracteriza, em termos econômicos, como uma das mais importantes enfermidades da cultura de trigo, pode também infectar uma vasta gama de gramíneas. Com o objetivo de conhecer as alterações metabólicas promovidas pelo mosaico do trigo, foram analisados os teores de açúcares totais e a concentração de prolina e determinou-se a atividade da nitrato redutase. O experimento foi conduzido na área experimental da Embrapa Trigo, usando cinco genótipos de trigo (BRS Guabiju, BRS 194, BRS 179, BR 23 e PF 980524) com diferentes níveis de resistência ao SBWMV. As determinações bioquímicas foram realizadas 45 dias após a emergência de plantas. A atividade da nitrato redutase foi mais elevada em plantas sem sintomas, quando comparada às com sintomas. Os níveis de açúcares e de prolina foram mais elevados em plantas com sintomas do que nas sem sintomas. Os resultados encontrados comprovam as alterações metabólicas promovidas pelo SBWMV nos cinco genótipos de trigo testados.