Elizabeth Aparecida Ferraz da Silva Torres

The influence of season on the lipid profiles of five commercially important species of Brazilian fish

This study aimed at determining the influence of season (summer and winter) the total lipid, fatty acid and cholesterol contents of five popular fish species: the sardine, Sardinella spp., the croaker Micropogonias furnieri (marine species), the curimbata Prochilodus spp., the tilapia, Oreochromis spp. (fresh water species), and the seabob shrimp, Xiphopenaeus kroyeri. Total lipid analysis was performed by the dry column; fatty acids were determined by gas chromatography and cholesterol was determined by a colorimetric method. Statistical treatment of results showed that sardines collected during winter had the highest lipid contents (10.62). The sardine, the croaker, the tilapia and the curimbata were not influenced by seasonality in terms of their total saturated and unsaturated acid contents. The highest contents of eicosapentanoic acid (3.02 and 1.87%) and docosahexaenoic acid (10.1 and 11.3%) were found in the sardine. The shrimp presented the highest cholesterol contents (165 mg/100 g in summer and 165 mg/100 g in winter).

Tomatoes and Tomato Products as Dietary Sources of Antioxidants

Tomatoes, as an agricultural product, represent an important commodity worldwide and comprise a significant part of the human diet. They are one of the most versatile and widely used fruits, being consumed in the raw state and used for the preparation of a wide range of products. Tomatoes and tomato products are rich in antioxidant compounds such as carotenoids (particularly lycopene), ascorbic acid and phenolic compounds. The regular consumption of tomatoes and tomato products has been correlated to a reduction in risk of contracting various types of cancer and cardiovascular diseases. This positive effect is attributed to the antioxidants present in tomatoes.

Parameters determining the quality of charqui, an intermediate moisture meat product

Charqui is a typical Brazilian meat product obtained by salting and sun-drying beef samples. The chemical, physical and microbiological characteristics of the charqui were evaluated throughout processing and storage. The results confirm charqui is an intermediate moisture meat product (A(w) = 0·70-0·75). A close relationship between moisture, pretein and ash vaiues was found, suggesting the possibility of using the resulting charqui A(w) value as a parameter to define the product instead of the official moisture and mineral residue contents. The TBA determination, which expresses the state of lipid oxidation, rapidly reached the maximum value, corroborating the previous observations on the salt pro-oxidant role, and then decreased gradually. A gradual decrease in microorganism count during processing and storage of charqui was also observed. These results indicate the feasibility of obtaining a final product with a low level of microbial count when raw materials of good quality, and adequate handling conditions, are used for charqui production.

Proximate food composition and caloric value of foods from animal origen

Proximate food composition data are very important to any professionals of food science and human nutrition area. In Brazil they are rare or do not exist. The food composition of items, of animal origin, usually consumed in the diet: meat, milk e eggs, were analyzed in order to determine their caloric value. After that they were compared with the data in the Tables of Food Composition (TFC) commonly used to our professionals. It was observed that there are smaller differences in the values obtained for eggs, than milk, pork, beef, chicken. Although significant difference was not detected between determined caloric values and the ones from TFC, these report should be considered to professionals that use the TFC.

Bioactive compounds content of chimarrão infusions related to the moisture of yerba maté (Ilex Paraguariensis) leaves

A erva mate (Ilex paraguariensis) e a materia prima para tres tipos de bebidas largamente consumidas na America do Sul. Substâncias bioativas presentes neste produto como a cafeina e os acidos clorogenicos tem recebido especial atencao da comunidade cientifica. O objetivo deste trabalho e avaliar o efeito do processamento da erva mate no teor de umidade das folhas e a eficiencia da extracao aquosa de algumas substâncias bioativas. Amostras de erva mate coletadas no Parana, Brasil foram objeto deste estudo. Cafeina, acidos fenolicos (acido cafeico e acido 5-cafeoilquinico) e flavonoides (quercitina, miricetina e caempferol) foram analisados por HPLC equipado com detector de arranjo de diodos. Os teores de acido 5-cafeoilquinico e cafeina do extrato aquoso variam em funcao da etapa do processamento (p 0,9). O acido cafeico foi determinado em 45% das infusoes obtidas das folhas secas e quercitina, miricetina e caempferol nao foram detectados nesses extratos.

Effect of salt on oxidative changes in pre- and post-rigor ground beef

Pre- and post-rigor beef was ground and salt was added to give 0·0, 0·5, 2·0 and 4·0% NaCl (w/w). Samples were removed after 0, 24, 48, 72 and 96 h at 4°C and analyzed for pH, TBA numbers and percentages of reduced myoglobin (Mb), metmyoglobin (MMb) and oxymyoglobin (MbO(2)). After holding for 96 h the samples were cooked in a boiling water bath to an internal temperature of 80°C and held at 4°C for 48 h before TBA analysis. Pre-rigor grinding and salting reduced the post-mortem pH decline and the extent of meat discoloration as shown by the differences in the amount of MMb. The extent of lipid oxidation as measured by TBA numbers was not significantly different for the pre- and post-rigor ground salted meat samples, although salt accelerated oxidation during storage. Results demonstrated that pre-rigor grinding and salting of beef produces a more stable bright red color, which appears to be associated with a lower percentage of MMb and a higher ultimate pH in the pre-rigor salted meat.

Effect of natural antioxidant combinations on lipid oxidation in cooked chicken meat during refrigerated storage

The effect of combinations of sage, oregano and honey on lipid oxidation in cooked chicken meat during refrigeration at 4°C for 96h was determined. Chicken samples (thigh and breast) were then separated into five groups: control; butylated hydroxytoluene; oregano+sage; oregano+sage+5%honey and oregano+sage+10%honey. Quantitative measurements of thiobarbituric acid reactive substances, conjugated dienes, hexanal, fatty acids, cholesterol and cholesterol oxides were used as indicators of lipid oxidation. Acceptability and preference were also evaluated. The effectiveness of the natural antioxidants for reducing the velocity of lipid oxidation in cooked chicken thigh and breast was demonstrated after 48 and 96h of refrigeration at 4°C. The treatments that presented the lowest hexanal values after 96h of refrigeration were oregano+sage+5%honey and oregano+sage+10%honey. Only traces of free cholesterol oxides were found (25-OH, 7-k, 7α-OH and 7β-OH). The natural antioxidants protected cooked chicken meat from oxidation processes and resulted in great acceptability.

Lipid raft disruption by docosahexaenoic acid induces apoptosis in transformed human mammary luminal epithelial cells harboring HER-2 overexpression.

In HER-2-overexpressing breast cells, HER-2 receptors exist on the cell surface as monomers, homodimers and heterodimers. For signal activation and transduction to occur, HER-2 must be localized to lipid rafts. Therefore, we hypothesized that the amount of lipid rafts on the cell membrane would be a factor in HER-2 signaling. To test this, we used HB4a (an untransformed human mammary epithelial cell line) and HB4aC5.2 cells. HB4aC5.2 cells are HB4a derivatives that have been transfected with five copies of pJ5E.c-ErbB-2 and express approximately 900 times more HER-2 than HB4a cells. In these cells, HER-2 overexpression was accompanied by increased lipid rafts in cell membranes, a hyperactivation of downstream Akt and ERK1/2 proteins, and an increased rate of cell growth compared to HB4a. In addition, HER-2 overexpression was associated with an increased activation of FASN, a key enzyme involved in cellular lipogenesis. Its final product, palmitate, is frequently used to synthesize lipid rafts. We further hypothesized that treatment with docosahexaenoic acid (DHA), an omega-3 fatty acid, would disrupt the lipid rafts and lead to a growth arrest. In HB4aC5.2 cells, but not HB4a cells, we found that DHA treatment disrupted lipid raft; inhibited HER-2 signaling by decreasing activation of Akt, ERK1/2 and FASN proteins; and induced apoptosis. Although little is known about lipid rafts, our data support the idea that disturbances in these microdomains induced by DHA may represent a useful tool for controlling the signaling initiated by HER-2 receptors and its therapeutic potential in the treatment of HER-2 positive breast cancer.

Fatty acid composition and palynological analysis of bee (Apis) pollen loads in the states of São Paulo and Minas Gerais, Brazil

SUMMARY The fatty-acid composition and botanical origin of 14 honey bee (Apis mellifera) pollen load samples acquired in shops and apiaries in Minas Gerais and São Paulo states, Brazil, were determined. The fatty acids presented a variable composition among these samples. All samples contained oleic, linoleic and arachidic acid. Only one sample did not contain palmitic acid. The unsaturated fatty-acid level varied from 18.6% to 55.9% of the total fatty-acid composition, suggesting that pollen is a good source of unsaturated fatty acids to the diet. Several pollen types were identified. Eucalyptus (Myrtaceae) and Eupatorium (Asteraceae) pollen types were the most common among those sampled. These data might help the regulatory agencies establish quality parameters for pollen produced in Brazil. There are no additional data available on Brazilian pollen fatty acid composition.

Paper-filtered coffee increases cholesterol and inflammation biomarkers independent of roasting degree: A clinical trial

OBJECTIVE The aim of this study was to compare the effects of medium light roast (MLR) and medium roast (MR) paper-filtered coffee on cardiovascular risk factors in healthy volunteers. METHODS This randomized crossover trial compared the effects of consuming three or four cups (150 mL) of MLR or MR coffee per day for 4 wk in 20 healthy volunteers. Plasma lipids, lipoprotein(a) (Lp[a]), total homocysteine, and endothelial dysfunction-related inflammation biomarkers, serum glycemic biomarkers, and blood pressure were measured at baseline and after each intervention. RESULTS Both roasts increased plasma total cholesterol, low-density lipoprotein-cholesterol, and soluble vascular cell adhesion molecule-1 (sVCAM-1) concentrations (10%, 12%, and 18% for MLR; 12%, 14%, and 14% for MR, respectively) (P < 0.05). MR also increased high-density lipoportein-cholesterol concentration by 7% (P = 0.003). Plasma fibrinogen concentration increased 8% after MR intake (P = 0.01), and soluble E-selectin increased 12% after MLR intake (P = 0.02). No changes were observed for Lp(a), total homocysteine, glycemic biomarkers, and blood pressure. CONCLUSION Moderate paper-filtered coffee consumption may have an undesirable effect on plasma cholesterol and inflammation biomarkers in healthy individuals regardless of its antioxidant content.