Production of grape juice powder obtained by freeze-drying after concentration by reverse osmosis.

This study aimed to evaluate the freeze-drying process for obtaining grape juice powder by reverse osmosis using 50% grape juice pre-concentrated (28.5 °Brix) and 50% hydrocolloids (37.5% maltodextrin and 12.5% arabic gum)

Identificação de carotenoides em polpa de goiaba microencapsulada utilizando cromatografia líquida de alta eficiência.

Título: goaiba [i.e. goiaba]

Morphological analysis of Yarrowia lipolytica under stress conditions through image processing

Yarrowia lipolytica is an aerobic microrganism capable to produce important metabolites, has an intense secretory activity which drives efforts to be employed in industry (as a biocatalyst), in molecular biology and genetics studies. Dimorphism is refeered to fungi ability to growth in two distinct forms, usually as single oval cells os as a filament and to be reversible between each one. The cell shape is controlled by environmental factors and has been seeked by some authors [1,2,3]. Y. lipolytica has been considered an adequate model for dimorphism studies in yeasts since it has an efficient system for transformation and is easy to distinct between its morphological forms, on opposite to S. cerevisiae that do not produce true filaments and exhibits pseudohyphae growth under nitrogen limited conditions. Y. lipolytica has an hyphae diameter corresponding 60 to 100% of its single cell stage [4,5]. It is believed that Y. lipolytica dimorphism is related to defense mechanism from adverse conditions. The aim of this work resides on investigate morphological changes in Y. lipolytica under thermal and oxidative stress conditions. Yarrowia lipolytica (IMUFRJ 50682) was cultivated in YPD medium (glucose 2%, peptone 0.64%, yeast extract 1%) at 29oC and 160 rpm. Thermal stress experiments were carried employing a temperature shift (37oC / 1 h.). For oxidative ones, an addition of H2O2 was used to reach final concentration of 10mM. Both stress conditions were applied at exponential growth phase. Morphology was observed in a optic microscope (Axiolab, Zeiss) and cell characteristics were determined employing image processing analysis (Matlab v. 6.1, The Mathworks Inc.) and comparisons were carried on to a control system. A net increase around 22% on hyphae formation was detected as well as a significant increment in its length in relation to control system, when both thermal and oxidative stress was applied. The results herein obtained drives to consider a possible relationship between dimorphism and a cell response mechanism to stress conditions.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundação para a Ciência e a Tecnologia (FCT); CAPES

Microencapsulation of guava pulp using prebiotic wall material.

Important functional compounds present in fruits are often lost in technological processes and during storage. Microencapsulation technique allows maintaining the compounds of interest and adding value to the product using functional encapsulating materials. This work aimed to produce microencapsulated guava pulp using the spray-drying technique and a functional encapsulant material, i.e., a mix of inulin and maltodextrin. The guava pulp was analyzed for centesimal composition, carotenoid content, and antioxidant activity. The microspheres were analyzed for retention of carotenoids, antioxidant activity over time, and morphology by Scanning Electron Microscopy (SEM) and X-ray diffraction. Two proportions of coating material could maintain the antioxidant activity of guava pulp. The microencapsulation with a higher percentage of inulin is a preferred option due to the good results of retention and stability regarding antioxidant activity over time, relevant retention of the carotenoid content, and a more stable microstructure. In addition, inulin can add value to powders owing to its inherent functional properties. The product obtained in the study is innovative and interesting, as well as may provide a capable use of these materials as encapsulated agents. In fact, it can be considered a potential functional ingredient.Microencapsulamento de polpa de goiaba com material de parede prebiótico

Produção de um suco de uva em pó, liofilizado e pré-concentrado por osmose inversa.

bitstream/item/164111/1/CT141-suco-uva-po.pd

Newborn screening for medium-chain acyl-CoA dehydrogenase deficiency: regional experience and high incidence of carnitine deficiency

Background Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is the most common inherited defect in the mitochondrial fatty acid oxidation pathway, resulting in significant morbidity and mortality in undiagnosed patients. Newborn screening (NBS) has considerably improved MCADD outcome, but the risk of complication remains in some patients. The aim of this study was to evaluate the relationship between genotype, biochemical parameters and clinical data at diagnosis and during follow-up, in order to optimize monitoring of these patients. Methods We carried out a multicenter study in southwest Europe, of MCADD patients detected by NBS. Evaluated NBS data included free carnitine (C0) and the acylcarnitines C8, C10, C10:1 together with C8/C2 and C8/C10 ratios, clinical presentation parameters and genotype, in 45 patients. Follow-up data included C0 levels, duration of carnitine supplementation and occurrence of metabolic crises. Results C8/C2 ratio and C8 were the most accurate biomarkers of MCADD in NBS. We found a high number of patients homozygous for the prevalent c.985A > G mutation (75%). Moreover, in these patients C8, C8/C10 and C8/C2 were higher than in patients with other genotypes, while median value of C0 was significantly lower (23 μmol/L vs 36 μmol/L). The average follow-up period was 43 months. To keep carnitine levels within the normal range, carnitine supplementation was required in 82% of patients, and for a longer period in patients homozygotes for the c.985A>G mutation than in patients with other genotypes (average 31 vs 18 months). Even with treatment, median C0 levels remained lower in homozygous patients than in those with other genotypes (14 μmol/L vs 22 μmol/L). Two patients died and another three suffered a metabolic crisis, all of whom were homozygous for the c.985 A>G mutation. Conclusions Our data show a direct association between homozygosity for c.985A>G and lower carnitine values at diagnosis, and a higher dose of carnitine supplementation for maintenance within the normal range. This study contributes to a better understanding of the relationship between genotype and phenotype in newborn patients with MCADD detected through screening which could be useful in improving follow-up strategies and clinical outcome