Estela de Rezende Queiroz

Constituintes químicos das frações de lichia in natura e submetidas à secagem: potencial nutricional dos subprodutos

A lichieira (Litchi chinensis Sonn.) e uma planta da familia das Sapindaceas, perfeitamente adaptada as condicoes climaticas brasileiras e pouco estudada quanto a composicao quimica de seus frutos, sobretudo das fracoes casca e semente, frequentemente descartadas pela industria e consumidores. Objetivou-se com este trabalho determinar os constituintes quimicos das fracoes casca, polpa e semente in natura, e da casca e semente submetidas a secagem a 45oC. Cada fracao foi avaliada em sete repeticoes (de 20 frutos), quanto a massa e a proporcao de cada fracao em relacao ao fruto inteiro, a composicao centesimal, ao valor energetico total (VET) e aos parâmetros quimicos e fisico-quimicos: solidos soluveis, pH e acidez titulavel. As fracoes casca e semente de lichia, juntas, representam cerca de 50% da massa do fruto. A casca e a semente da lichia apresentam elevados VETs e teores de carboidratos. A casca possui os maiores teores de fibra (bruta e alimentar), lipideos, cinzas e proteinas, e a polpa apresenta maior acidez, menor pH e maiores teores de solidos soluveis. A secagem aumentou o pH da semente e os teores de solidos soluveis da casca e semente. As fracoes de lichia apresentaram elevados potenciais energeticos e nutricionais, podendo ser aproveitadas como fonte alternativa de nutrientes, desde que nao apresentem fatores antinutricionais em quantidades prejudiciais ao organismo.

Bioactive phytochemicals and antioxidant activity in fresh and dried lychee fractions

Fruit of the lychee cv. Bengal are approximately 50% peel and seeds, which are discarded. These by-products have antioxidant compounds which are capable of blocking the harmful effects of free radicals in the body. Bioactive compounds (ascorbic acid, beta-carotene, lycopene and phenols) and antioxidant activity were evaluated in different extracts, both fresh and dried at 45 °C, of the skin, pulp and seeds of the lychee, which were subjected to principal component analysis to clarify which of the compounds are responsible for this activity. Principal component analysis explained 82.90% of the variance of the antioxidant profile of the lychee. The peel displayed higher levels of phenols, ascorbic acid, beta-carotene and antioxidant activity, while the seeds stood out due to their levels of lycopene. With drying, there was a decrease in the levels of ascorbic acid and beta-carotene and in antioxidant activity, with an increase in the levels of phenols and lycopene. The antioxidant activity found in the peel and seeds of the lychee is high, and is mainly due to ascorbic acid and beta-carotene, as demonstrated by principal component analysis, allowing the use of these fractions as sources of natural antioxidants.

Anti-nutritional compounds in fresh and dried lychee fractions (Litchi chinensis Sonn.)

The present study evaluated the anti-nutritional factors of “Bengal” lychee (Litchi chinensis Sonn.), in the fresh pulp, peel and seed, both fresh and processed. The samples were analyzed for the levels of phenolic compounds, nitrate, oxalic acid and inhibitory activities of trypsin, lipase and α-amylase. Drying influenced the activity of all enzyme inhibitors, resulting in a reduction in the inhibitory activity of lipase (0.13 and 0.15 lipase inhibitor units for peel and seed, respectively) and an increase in the inhibitory activities of trypsin (10.14 and 10.66 trypsin inhibitor units for peel and seed, respectively) and α-amylase (1.13 and 1.08 amylase inhibitor units for peel and seed, respectively). With drying, it was possible to observe an increase in the levels of phenolic compounds, the low content of nitrate did not change with drying, while oxalic acid was not detected. The antinutrients evaluated in lychee fractions are present in amounts that do not preclude its use; thus, the use of lychee fractions, fresh or dried, is feasible as nutrient sources and add value to the fruits, since industries can use these residues for developing new products, as well as in food enrichment.

Emprego da farinha e do extrato de frutanos de yacon na elaboração de apresuntados

The objective of this study was to develop two luncheon meat formulations containing yacon flour and yacon fructan extract, in order to obtain products with improved nutritional quality and rich in dietary fiber. The luncheon meats were prepared replacing the cassava starch (1.73%) with yacon flour, and the water used in the formulation (37.85%) with the aqueous fructan extract. The effects of these substitutions on the technological and sensory qualities of the luncheon meats were evaluated, comparing them with a control. The results obtained showed there were significant differences between the formulations. The addition of yacon flour to the luncheon meat resulted in a formulation with a lower sodium content, yellow index, hue, hardness, flexibility and adhesion and lower scores for the items of taste and overall impression. However, they showed that the luncheon meat prepared with the fructan extract presented an acceptability similar to that of the control, but with reduced hardness and higher levels of potassium and fiber, resulting in a meat product beneficial to the health.

High-dose fluconazole in combination with amphotericin B is more efficient than monotherapy in murine model of cryptococcosis

Cryptococcus spp., the causative agents of cryptococcosis, are responsible for deaths of hundreds of thousands of people every year worldwide. The drawbacks of available therapeutic options are aggravated by the increased resistance of yeast to the drugs, resulting in inefficient therapy. Also, the antifungal 5FC is not available in many countries. Therefore, a combination of antifungal drugs may be an interesting option, but in vitro and theoretical data point to the possible antagonism between the main antifungals used to treat cryptococcosis, i.e., fluconazole (FLC), and amphotericin B (AMB). Therefore, in vivo studies are necessary to test the above hypothesis. In this study, the efficacy of FLC and AMB at controlling C. gattii infection was evaluated in a murine model of cryptococcosis caused by C. gattii. The infected mice were treated with FLC + AMB combinations and showed a significant improvement in survival as well as reduced morbidity, reduced lung fungal burden, and the absence of yeast in the brain when FLC was used at higher doses, according to the Tukey test and principal component analysis. Altogether, these results indicate that combinatorial optimization of antifungal therapy can be an option for effective control of cryptococcosis.

Caracterização química e efeito cicatrizante de quitosana, com baixos valores de massa molar e grau de acetilação, em lesões cutâneas

Several researches look for drugs with healing properties, capable to cure skin lesions. The objective of this study was to chemically characterize one chitosan and evaluate its healing effects in mice skin lesions. The chitosan was characterized in relation to the viscosity, molar mass, acetylation degree, elementary analysis, thermogravimetry and infrared spectroscopy. To evaluate the healing properties of chitosan mices were submitted to tissue excision and treated during 21 days. The macroscopic parameters were weekly evaluated and the microscopic parameters at the end of the experiment. Chitosan presented viscosity of 5 mPa s, low acetylation degree (GA= 5.9%) and molar mass of 132.0 kDa. By elemental analysis, we observed that the composition of chitosan is similar to the formula C6H11O4N, its main characteristic bands were observed in the infrared spectrum and the thermogravimetric curve showed two decomposition steps. There was no significant difference on the histology between the control and the treated group after the 21st day of lesion. Macroscopically, chitosan caused the reduction of 81.4% of the lesions width, which is significantly superior to the observed reduction in the control group (71.2%), thus helping the cure of skin lesions. These results reinforces its potential use for medical application.

Preparação, caracterização e análise sensorial de pão integral enriquecido com farinha de subprodutos do mamão

Due to the industrial processing of papaya, a great amount of byproducts from this fruit is generated. The peel and seeds are amongst these byproducts and have great nutritional value, since they present considerable amounts of fibre, lipids, proteins and antioxidants. The objective of this study was to develop whole wheat bread loaves with the addition of a mixed flour made from the peel and seeds of papayas of the Hawaiian cultivar. In the whole-grain breadmaking process, the mixed flour (peel and seeds) was added in different concentrations (0%, 3%, 6% and 9%), in the proportion of 70% of papaya peel flour to 30% of papaya seed flour. The addition of the mixed flour resulted in products with high fibre (7.96 g 100 g-1) and protein (12.71 g 100 g-1) contents and low lipid contents (0.55 g 100 g-1). The results of the sensory analysis showed that the bread made with the addition of 3% of the mixed flour resulted in good acceptance when compared to the control. Thus the addition of papaya byproducts flour in the manufacture of bread is a good alternative for the diet of the population, since it is nutritionally rich in fibre and protein.

Qualidade de pitaia (Hylocereus undatus) submetida à adubação orgânica e armazenada sob refrigeração

Abstract In this work the effect of organic fertilization associated with refrigeration on red pitaya quality was investigated. For 4 years the plants were fertilized every three months according to the following treatments: control (no fertilization) (T1); bovine manure (14 kg / plant) (T2); chicken manure (2 kg / plant) (T3) and chicken manure (2 kg / plant) + bovine manure (14 kg / plant) (T4). The fruits were stored for 21 days at 13 °C and evaluated on days 0, 7, 14 and 21 for loss of fresh mass, colour, firmness, total titratable acidity (TTA), pH, total soluble solids (TSS), TSS / TA, total sugars and reducing and non-reducing sugars. The results showed that during refrigerated storage of the pitaya fruits, the organic fertilization treatments interfered with the quality parameters evaluated, attenuating the loss of fruit quality. It should be highlighted that fertilization with bovine manure associated with chicken manure proved to be more effective than the other organic fertilizers, and resulted in fruits with reduced quality losses during storage.

Lychee (Litchi chinensis Sonn.) peel flour: effects on hepatoprotection and dyslipidemia induced by a hypercholesterolemic diet

Dyslipidemias are associated with the incidence of cardiovascular diseases, obesity, diabetes, hypertension and hepatic steatosis, being the cause of morbidity and mortality. This study investigated the effects of lychee peel flour (PF) on serum levels of total cholesterol (TC), low-density lipoprotein (LDL-c), triacylglycerols (TAG) and various parameters related to obesity, in rats fed a hypercholesterolemic diet. Therefore, 20 male rats were used. In the first 21 days, the animals were fed a hypercholesterolemic diet, except for control group. In the following 21 days, their diets were modified, and they received a standard diet (Control); hypercholesterolemic (Hyper); hypercholesterolemic + 5% PF (PF5) and hypercholesterolemic + 10% PF (PF10). The results revealed that PF intake attenuated weight gain, reduced body mass index, glucose and the levels of TAG, TC, LDL-c, hepatic enzymes and leptin, besides the percentage of hepatic lipids, liver lipid peroxidation and frequency of severe steatosis. Histological studies of the aorta did not show the formation of the atheromatous plaque. These results reinforce its potential to reduce the risk of diseases associated with obesity.