ANTIOXIDANT POTENTIAL ACTIVITY, IN VITRO, OF THE GRAPE SKIN AND SEEDS OBTAINED AFTER THE FIRST STAGE OF VINIFICATION FROM VITIS VINIFERA CV. TANNAT AND VITIS LABRUSCA CV. BORDEAUX.

The analysis of antioxidant potential activity, from skins and seeds of the species Vitis vinifera cv. Tannat and Vitis labrusca cv. Bordeaux, obtained after the first stage of fermentation of their respective wines, performed from crude ethanol extract. Dried skins and seeds of the species Vitis vinifera cv. Tannat and Vitis labrusca cv. Bordeaux, obtained after the first stage of fermentation of their respective wines, analyzed for antioxidant potential. For that, a crude ethanol extract made. First, a Liquid Chromatography High Efficiency (HPLC) method was developed for detection and confirmation of the presence of the compounds responsible for antioxidant potential in grapes The antioxidant potential was verified using three types of tests: DPPH (2,2-diphenyl-1-picrylhydrazyl), phosphomolybdenum complex, and lipid peroxidation (TBARs- thiobarbituric acid). The results showed that even though there is an extraction of phenolic compounds during alcoholic fermentation, the remaining material still possesses various phenolic compounds that maintain their antioxidant characteristics. Antioxidation capabilities were more active with DPPH, then in lipid peroxidation, and the lowest result concerning the standards analyzed with phosphomolybdenum method. Statistical analysis showed no significant difference between the 5% level between the two varieties studied. These results show the presence of compounds with antioxidant activity in the waste from winemaking and for this reason, the analyzed material is promising for use in various pharmaceutical fields such as medicines, cosmetic and food technology. The present study aimed to clarify the existence of antioxidative properties in the wine waste thus adding value to the residue

FUNCTIONAL FOODS: AN UPDATE

Os governos e a população em geral estão se concentrando na promoção da saúde com medidas preventivas, e entre as estratégias utilizadas está a alimentação saudável. Isto provocou o surgimento de um novo conceito sobre o alimento. O alimento funcional termo que apareceu pela primeira vez na revista Nature em 1993, com uma chamada que dizia respeito ciências farmacêuticas e nutrição com o uso de alimentos como forma de prevenção da doença. Hoje o termo alimento funcional é definido pela Associação Americana de Dietética como sendo alimentos com efeitos potencialmente benéficos para a saúde, além dos efeitos tradicionais de seus nutrientes. No entanto, o conceito de alimentos funcionais é muito evasivo ao público em geral, levantando muitas perguntas. Desta forma, o presente artigo procura contribuir para a compreensão do conceito e seu uso pelos consumidores e produtores

Isolamento e seleção de fungos produtores de β-galactosidase

Os micro-organismos representam a maior diversidade biológica, química, molecular e fisiológica dos seres vivos, e o isolamento a partir de recursos naturais, como o solo, é de grande importância para a obtenção de novas linhagens. O objetivo deste trabalho foi isolar e selecionar linhagens de fungos com potencial para a produção de β-galactosidase, com atividade de transgalactosilação. Foram coletadas amostras de solos, feitas diluições seriadas e inoculadas, em ágar Sabouraud modificado com lactose. Os fungos foram repicados até a obtenção de colônias isoladas e os micro-organismos selecionados foram identificados por cultivo entre lâmina e lamínula. O processo fermentativo para a produção da enzima foi feito no estado sólido com lactose a 1% (p/v) em frascos de cultura e mantido a 26 ºC por 7 dias. A β-galactosidase produzida foi parcialmente purificada com etanol e determinados os efeitos do pH e da temperatura na atividade enzimática, por meio de planejamento fatorial de dois níveis. A atividade de transgalactosilação foi avaliada, variando o pH e a concentração da enzima e o perfil dos carboidratos obtidos foi analisado por cromatografia líquida de alta eficiência. O fungo que expressou a maior atividade de β-galactosidase foi identificado como Penicillium sp e apresentou para a atividade enzimática os valores ótimos de pH e temperatura de 4,5 e 60 ºC, respectivamente. A β-galactosidase produzida pelo fungo Penicillium sp apresentou atividade hidrolítica e de transgalactosilação, tendo potencial para ser explorada industrialmente na produção de prebióticos. Palavras-chave: Fungos filamentosos. Fermentação no estado sólido. Galacto-oligossacarídeos, Transgalactosilação

Screening of whole yeast free-cells and optimization of pH and temperature for fructooligosaccharides production

Fructooligosaccharides are catalyzed by β–fructofuranosidase enzyme, produced by many microorganisms. However, in order to achieve a more profitable, low time-consuming process with lower cost, researchers have sought alternatives. This study aimed to select and identify yeasts able to produce fructooligosaccharides and evaluate the influence of pH and temperature on their synthesis. Yeast suspensions, solutions of 500 g L-1 sucrose and three values of pH (4.5, 5.5, and 6.5) and temperature (40, 50, and 60ºC) were tested. Yeast species were identified by molecular techniques. Among 141 yeast isolates from grapes, 65 were able to synthesize fructooligosaccharides. The maximum concentration of fructooligosaccharides was 4.8% (w v-1), and Saccharomyces cerevisiae 222 produced 1-kestose and nystose.

<b>Composition of amino acids and bioactive amines in common wines of Brazil

Since most consumed wines in Brazil are common wines and since their representativeness is not accounted for in scientific research, current study quantifies bioactive amines and their precursors in Brazilian sweet and dry common wines, correlates the formation of amines with physical and chemical parameters and clusters studied areas by their amine and amino acid contents. Forty-seven wine samples varying in type, color and origin were analyzed simultaneously for seventeen amino acids, ammonium ion and five bioactive amines by reversed-phase high performance liquid chromatography and ultraviolet detection after the derivation phase. Physical and chemical analyses comprised titratable acidity, pH, organic acids, sugar and alcohol contents. Sweet wines had lower concentrations of amino acids and bioactive amines. Dry white wines had higher amino acid contents when compared to those in dry red wines. Since multivariate data analysis confirmed similarities between the studied regions, their unity as potential viniculture area was reinforced. Amine levels in Brazilian common wines were reported for the first time and results reinforced the importance of bioactive amines quantification and the use of suitable vinification practices to reduce their formation

Otimização da produção de biomassa e astaxantina pela levedura Phaffia rhodozyma

A combinação de processos descontínuo alimentado e matérias-primas de baixo custo (caldo de cana-de-açúcar e uréia) foi estudada a fim de otimizar a produção de biomassa e astaxantina pela levedura Phaffia rhodozyma ATCC 24202. No processo otimizado, produtividades em biomassa e astaxantina de 0,327 g/L/h e 0,124 mg/L/h foram obtidas, respectivamente. Comparadas com o processo descontínuo estudado, verificou-se aumento de 4,55 vezes na produtividade em biomassa e 4,73 vezes na produtividade em astaxantina.The combination of fed-batch processes and low cost substrates (sugar cane juice and urea) was studied in view of the optimization of biomass and astaxanthin production by the yeast Phaffia rhodozyma ATCC 24202. In the optimized process, a biomass and astaxanthin productivity of 0.327 g/l/h and 0.124 mg/l/h was achieved, respectively. Compared to the batch process studied, an increase of approximately 4.55-fold in the biomass productivity and 4.73-fold in the astaxanthin productivity was found

Iron enriched Saccharomyces cerevisiae maintains its fermenting power and bakery properties

Iron is an essential micronutrient in the metabolism of almost all living organisms; however, its deficiency is well documented especially in pregnant women and in children. Iron salts as a dietary supplement have low bioavailability and can cause gastrointestinal discomforts. Iron enriched yeasts can provide a supplementation of this micronutrient to the diet because this mineral has a better bioavailability when bonded to yeast cell macromolecules. These yeasts can be used as feed supplement for human and animals and also as baker's yeast. Baker's yeast Saccharomyces cerevisiae was cultivated in a reactor employing yeast media supplemented with 497 mg ferrous sulfate.L-1, and the resultant biomass incorporated 8 mg Fe.g-1 dry matter. This biomass maintained its fermenting power regarding both water displace measurement through carbonic dioxide production and bakery characteristics. The bread produced using the yeast obtained by cultivation in yeast media supplemented with iron presented six times more iron than the bread produced using the yeast obtained by cultivation without iron supplementation

Autochthonous yeasts with β-glucosidase activity increase resveratrol concentration during the alcoholic fermentation of Vitis labrusca grape must

AbstractSince red wine is the main dietary source of resveratrol, a well-known polyphenol that reduces coronary events in humans, different strategies have been employed in winery to achieve resveratrol-enriched wines. Yeasts-endowed β-glucosidase activity enhances free-resveratrol concentration in wine without modifying its composition or sensorial properties. Current assay screened 308 autochthonous yeast strains for β-glucosidase activity employing arbutin, esculin, cellobiose and piceid as substrates. The β-glucosidase-producer yeasts were evaluated in the must of Vitis labrusca Bordô grape to quantify resveratrol concentration before and after alcoholic fermentation. Fourteen yeasts increased the resveratrol concentration up to 102% without any significant difference and nine of these yeast strains also produced high ethanol contents. Four autochthonous Hanseniaspora uvarum β-glucosidase-producer strains showed adequate oenological characteristics and hydrolysed resveratrol-glucosides during the alcoholic fermentation of V. labrusca grape must