Losses of immunoreactive parvalbumin amacrine and immunoreactive alphaprotein kinase C bipolar cells caused by methylmercury chloride intoxication in the retina of the tropical fish Hoplias malabaricus

To quantify the effects of methylmercury (MeHg) on amacrine and on ON-bipolar cells in the retina, experiments were performed in MeHg-exposed groups of adult trahiras (Hoplias malabaricus) at two dose levels (2 and 6 µg/g, ip). The retinas of test and control groups were processed by mouse anti-parvalbumin and rabbit anti-alphaprotein kinase C (alphaPKC) immunocytochemistry. Morphology and soma location in the inner nuclear layer were used to identify immunoreactive parvalbumin (PV-IR) and alphaPKC (alphaPKC-IR) in wholemount preparations. Cell density, topography and isodensity maps were estimated using confocal images. PV-IR was detected in amacrine cells in the inner nuclear layer and in displaced amacrine cells from the ganglion cell layer, and alphaPKC-IR was detected in ON-bipolar cells. The MeHg-treated group (6 µg/g) showed significant reduction of the ON-bipolar alphaPKC-IR cell density (mean density = 1306 ± 393 cells/mm²) compared to control (1886 ± 892 cells/mm²; P < 0.001). The mean densities found for amacrine PV-IR cells in MeHg-treated retinas were 1040 ± 56 cells/mm² (2 µg/g) and 845 ± 82 cells/mm² (6 µg/g), also lower than control (1312 ± 31 cells/mm²; P < 0.05), differently from the data observed in displaced PV-IR amacrine cells. These results show that MeHg changed the PV-IR amacrine cell density in a dose-dependent way, and reduced the density of alphaKC-IR bipolar cells at the dose of 6 µg/g. Further studies are needed to identify the physiological impact of these findings on visual function.

High HTLV-1 proviral load, a marker for HTLV-1 associated myelopathy/tropical spastic paraparesis, is also detected in patients with infective dermatitis associated with HTLV-1

Salvador (BA, Brazil) is an endemic area for human T-cell lymphotrophic virus type 1 (HTLV-1). The overall prevalence of HTLV-1 infection in the general population has been estimated to be 1.76%. HTLV-1 carriers may develop a variety of diseases such as adult T-cell leukemia/lymphoma, HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and infective dermatitis associated with HTLV-1 (IDH). IDH is a chronic and severe form of childhood exudative and infective dermatitis involving mainly the scalp, neck and ears. It has recently been observed that 30% of patients with IDH develop juvenile HAM/TSP. The replication of HTLV-1 has been reported to be greater in adult HAM/TSP patients than in asymptomatic HTLV-1 carriers. In the current study, the proviral load of 28 children and adolescents with IDH not associated with HAM/TSP was determined and the results were compared to those obtained in 28 HTLV-1 adult carriers and 28 adult patients with HAM/TSP. The proviral load in IDH patients was similar to that of patients with HAM/TSP and much higher than that found in HTLV-1 carriers. The high levels of proviral load in IDH patients were not associated with age, duration of illness, duration of breast-feeding, or activity status of the skin disease. Since proviral load is associated with neurological disability, these data support the view that IDH patients are at high risk of developing HAM/TSP.

Estabilidade do suco tropical de acerola (Malpighia emarginata d.c.) adoçado envasado pelos processos hot-fill e asséptico

Este trabalho objetivou avaliar a estabilidade do suco tropical de acerola adoçado, elaborado pelos processos hot fill (garrafas de vidro) e asséptico (embalagens cartonadas), com relação às alterações químicas e físico-químicas (pH, sólidos solúveis totais, acidez total titulável, cor, açúcares redutores, não redutores e totais), sensoriais e microbiológicas, durante 350 dias de armazenamento em condições similares às de comercialização (28 °C ± 2 °C). Ao final do experimento, constatou-se que as amostras de suco de ambos os processos mantiveram uma adequada estabilidade microbiológica. O suco do processo hot fill teve maior aceitação global, enquanto o do processo asséptico manteve, ao final dos 350 dias, a aceitação inicial. As amostras do processo asséptico apresentaram inicialmente melhor sabor em comparação com as do processo hot fill, no entanto, as do processo hot fill mantiveram o sabor estável, enquanto o sabor do suco do processo asséptico teve menor aceitação ao longo do armazenamento. Ainda foram observadas, alterações químicas e físico-químicas nos sucos de ambos os processos. Em geral, o processo hot fill foi o mais eficiente em manter a estabilidade do suco.

Quality evaluation of fresh-cut ‘Pérola’ pineapple stored in controlled atmosphere

The purpose of this research was to determine the best gas mixture in controlled atmosphere conditions to store fresh-cut ‘Pérola’ pineapple, particularly in relation to the maintenance of visual quality and reduction of microbial growth. After sanitation, fruit was manually peeled, sliced and dipped in 20 mg.L-1 NaOCl solution for 30 seconds. Then, the excess liquid was drained and the slices were placed in sealed glass jars connected to a flowboard installed in a cold room (5 ± 1 °C). Desired gas mixtures were supplied continuously for 12 days from cylinders connected to the flowboard. Controlled atmospheres of 2:5, 2:10, 2:15, 5:5, 5:10, 5:15, 8:5, 8:10 and 8:15 (O2:CO2, %) and air were used. The product was evaluated for pulp color, total and fecal coliforms, mesophilic and psychrotrophic aerobic, mold and yeast counts. Total and fecal coliforms were not detected. The fresh-cut ‘Pérola’ pineapple was not very sensitive to storage in controlled atmosphere, considering that the slices had little browning and were free of contamination, that would affect the food safety at the end of the storage period

Volatile compounds profile of fresh-cut peki fruit stored under different temperatures

The objective of this work was to identify and verify the influence of time and temperature on the volatile compounds profile of fresh cut peki. Peki fruits were washed, sanitized, their kernels were extracted, and they were packaged and stored for 15 days at 0, 5, and 10 °C and 6 days at 22 °C. The volatiles compounds were analyzed by GC - MS. Ethyl hexanoate and ethyl octanoate were found in higher percentages, 63 and 16.3%, respectively. The determined volatiles were not influenced by the storage period. Hexanoic acid, ethyl 2-octenoate and ethyl decanoate were not influenced by the different temperatures. The temperatures 0, 5, and 10 °C did not influence ethyl hexanoate, ethyl 2-hexenoate and ethyl octanoate either. In addition, the temperatures 5, 10, and 22 °C did not influence ethyl hexanoate, cis-β-ocimene and ethyl octanoate. The temperature of 22 °C determined higher percentages of ethyl hexanoate and lower percentages of ethyl octanoate, in comparison to the temperature of 0 °C, and higher percentages of ethyl 2-hexenoate in comparison to the temperatures of 0, 5, and 10 °C. The temperature of 5 °C determined higher percentage of cis-β-ocimene when compared with the temperature of 0 °C. The storage temperatures of 0 and 5 °C were the most appropriate for the conservation.

Quality of minimally processed guava with different types of cut, sanification and packing

The purpose of this project was to evaluate the sanitization effect on the quality of minimally processed guava. Initially, research was carried out with consumers in a supermarket to verify preferences of packaging for guava. Following this, the guava cv. Paluma underwent two sanitization sequences using dehydrated sodium dichloroisocyanurate compound, in 50 ppm concentration, sanitization prior to (S1) and after (S2) being cut; removal of excess water; conditioning in PET packaging and PSPVC and storage at 3 ºC ± 1 ºC. Physicochemical analysis - [pH, total soluble solids (SST), total labeled acidity (ATT), ascorbic acid (AA), total sugars (AT) and reducers (AR)], textural sensorial and microbiological analyses were used to monitor the quality of the products. The consumers preferred the guava cut in halves with pulp and packed in PET, although this packaging promoted condensation of water vapor on the inner surface of the lid, compromising the appearance of the product. The two sanitization sequences and the two kinds of packaging did not significantly affect the pH, SST, ATT, SST/ATT, texture and AA values. The AT and AR tenors increased significantly in the MP guavas stored in the PSPVC package. Both sanitizations were efficient in the bacterial control of the indicators of the hygienicsanitary conditions, although the S1 sanitization proved to be more efficient in the control of autochthonous aerobic microbiota (aerobic mesophylic microorganisms). It can be concluded that guava cv. Paluma packed in PSPVC can be conserved for 6 days when stored at 3 ºC.

Estabilidade de componentes bioativos do suco tropical de goiaba não adoçado obtido pelos processos de enchimento a quente e asséptico

A goiaba é um dos frutos tropicais de maior valor nutricional, rico em vitamina C e pró-vitamina A, possuindo uma excelente aceitação para consumo in natura, como também uma vasta aplicação industrial. A vitamina C, os carotenoides, as antocianinas e os compostos fenólicos são considerados substâncias com atividade antioxidante, e seu consumo regular tem ação protetora efetiva contra os processos oxidativos que naturalmente ocorrem no organismo. Este trabalho objetivou estudar a estabilidade da vitamina C, carotenoides totais, antocianinas totais e compostos fenólicos totais do suco tropical de goiaba não adoçado obtido pelos processos de enchimento a quente e asséptico durante 250 dias de armazenamento à temperatura ambiente (28 ± 2 ºC). Os resultados demonstraram que os conteúdos de carotenoides totais e os fenólicos totais não apresentaram variação durante o armazenamento, enquanto que a vitamina C apresentou redução.

Volatile profile and physical, chemical, and biochemical changes in fresh cut watermelon during storage

Existing data about the aroma of fresh-cut watermelon and the metabolic changes that occur with minimal processing are scarce. Given the close relationship that exists between aroma, texture, and quality characteristics, it is necessary to investigate the changes in the volatile profile and texture of watermelon, a fruit extensively sold in supermarket chains throughout Brazil. The objective of this work was to analyze the volatile profile using solid phase microextraction (SPME) as well as texture changes in fresh-cut watermelon stored at 5 °C for ten days. Chromatography associated with sensory analysis (sniffing) led us to conclude that 9-carbon (C9) alcohols and aldehydes are the major responsible for the flavor and aroma of minimally processed watermelon stored at 5 ± 1 °C/90 ± 5% RH for ten days, and also that the aroma diminishes in intensity with storage, but it does not affect the final quality of the product. It was noted that the amount of drained liquid, soluble pectin, and weight loss increased during storage concurrently with a reduction in firmness and a structural breakdown of the cells. Pectin methyl esterase activity remained constant and polygalacturonase activity was not detected.

Physicochemical and microbiological characterization of cassava flower honey samples produced by africanized honeybees

Cassava producers in the region of Marília-São Paulo are integrating their farming activity with beekeeping to diversify their income. The aim of this study was to evaluate the physicochemical and microbiological quality of honey samples produced by Africanized honeybees Apis mellifera from cassava flower in 2008. Analysis were carried out for pH, total soluble solids (TSS), acidity, moisture, reducing and total sugars, apparent sucrose, hydroxymethylfurfural, color, ash, proteins, water insoluble solids, diastasic activity, mineral content, microbiological evaluations, and mineral and hydrocyanic acid (HCN) content. The honey samples showed physicochemical and microbiological characteristics favorable to commercialization, with the exception of apparent sucrose and acidity, which show the need for a narrow focus of attention to the honey maturation degree at the harvest time and more careful monitoring during production and processing. The commercialization of Brazilian cassava honey, still little explored, can be widely spread in the market since the levels of hydrocyanic acid (HCN) showed no consumption risk; in addition the simultaneous production of honey and cassava provides an alternative to family income increase.

Estimate of respiration rate and physicochemical changes of fresh-cut apples stored under different temperatures

In this study, the influence of storage temperature and passive modified packaging (PMP) on the respiration rate and physicochemical properties of fresh-cut Gala apples (Malus domestica B.) was investigated. The samples were packed in flexible multilayer bags and stored at 2 °C, 5 °C, and 7 °C for eleven days. Respiration rate as a function of CO2 and O2 concentrations was determined using gas chromatography. The inhibition parameters were estimated using a mathematical model based on Michaelis-Menten equation. The following physicochemical properties were evaluated: total soluble solids, pH, titratable acidity, and reducing sugars. At 2 °C, the maximum respiration rate was observed after 150 hours. At 5 °C and 7 °C the maximum respiration rates were observed after 100 and 50 hours of storage, respectively. The inhibition model results obtained showed a clear effect of CO2 on O2 consumption. The soluble solids decreased, although not significantly, during storage at the three temperatures studied. Reducing sugars and titratable acidity decreased during storage and the pH increased. These results indicate that the respiration rate influenced the physicochemical properties.

Effect of thinning on flower and fruit and of edible coatings on postharvest quality of jaboticaba fruit stored at low temperature

Jaboticaba is a Brazilian fruit, native to the Atlantic forest, which belongs to the Myrtaceae family. In this work we describe the effect of the thinning of "flower", "fruit" and "flower & fruit" compared to non-thinned fruit (control) and of edible coatings with respect on nutritional composition, overall acceptability and shelf-life of jaboticaba ‘Sabara’, grown in an irrigated commercial orchard. "Flower and fruit" thinning allows fruit with higher quality as diameter, volume and mass. Non-thinned fruit shows higher yield, however fruit have lower quality. As a result of the improving quality at harvest, the shelf life was twice (~8 days) for thinned fruit. The lack of change in concentration of soluble sugar and absence of formation of volatile compounds during storage indicate that there was no natural fermentation of the jaboticaba pulp after harvest. Treatments with wax and calcium did not improve the jaboticaba shelf life.

Biochemical and color changes of fresh-cut melon (Cucumis melo L. cv. Galia) treated with UV-C

The importance of minimally processed commodities in the retail groceries of most developed countries has been rising continuously during the last decades. Cantaloupe melon is used more than any other fruit in fresh-cut processing. Ultraviolet (UV) light has been extensively used to simulate biological stres in plants and for determining resistance mechanisms of plant tissues. In this study the effect of ultraviolet irradiation on some properties of fresh-cut cantalope melon was determined during storage. Freshly cut cantalope melons cubes treated with ultraviolet irradiation at the doses of 1, 2 or 3 min before storage, and then placed in a cold room at 5±1°C temperature and 85-90% RH. Hue angle values of control group is low compared to UV-C treated samples, whereas L values of is high. EL of UV treated samples higher than those of control group. Total soluble solids of fresh-cut melon samples in UC3 treatment increased during storage. The results indicate that UV-C treatments on fresh-cut cantaloupe melon cubes increased total soluble solids independently from water loss.

Glycemic index and glycemic load of tropical fruits and the potential risk for chronic diseases

The objective was to determine the glycemic index and glycemic load of tropical fruits and the potential risk for chronic diseases. Nine fruits were investigated: coconut water (for the purpose of this study, coconut water was classified as a “fruit”), guava, tamarind, passion fruit, custard apple, hog plum, cashew, sapodilla, and soursop. The GI and GL were determined according to the Food and Agriculture Organization protocol. The GL was calculated taking into consideration intake recommendation guidelines; 77.8% of the fruits had low GI although significant oscillations were observed in some graphs, which may indicate potential risks of disease. Coconut water and custard apple had a moderate GI, and all fruits had low GL. The fruits evaluated are healthy and can be consumed following the daily recommended amount. However, caution is recommended with fruits causing early glycemic peak and the fruits with moderated GI (coconut water and custard apple).

Biochemical changes and color properties of fresh-cut green bean (Phaseolus vulgaris L. cv.gina) treated with calcium chloride during storage

Calcium chloride is widely used in industries as a firming agent, and also to extend shelf-life of vegetables. The aim of this study was to determine, the effect of different doses of calcium chloride on biochemical and color properties of fresh-cut green bean. Fresh-cut green beans were dipped for 90 seconds in 0.5%, 1%, 2% and 3% solution of calcium chloride at 25°C. The fresh-cut green bean samples were packaged in polystyrene foam dishes, wrapped with stretch film and stored in a cold room at 5±1°C temperature and 85-90% RH. Calcium chloride treatments did not retain the green color of samples. Whiteness index, browning index and total color difference (ΔE) values of CaCl2 treated samples were high. Saturation index and hue angle were low compared to the control, especially at higher doses of CaCl2. Polyphenol oxidase (PPO) enzyme activity in samples treated with CaCl2 at 3% doses, was low at the 7th days of storage than with other treatments. Fructose and sucrose content of samples increased in all treatment groups whereas glucose level decreased during the first 4th days of storage.