Resumo Uma das mais importantes classes de moléculas nutricionais é a dos compostos oleaginosos, a qual inclui especialmente os óleos-lipídeos, os carotenoides e os ácidos graxos. Esses compostos apresentam um vasto campo de aplicações industriais pela habilidade de atuarem como fonte de energia para o corpo humano, antioxidantes e agentes metabólicos. Sendo assim, a indústria de alimentos, focando principalmente na suplementação de alimentos, está sempre procurando novas fontes deles. Nesse contexto, o presente estudo avaliou a produção simultânea de lipídeos totais, carotenoides e ácidos graxos pela levedura Rhodotorula mucilaginosa CCT3892, utilizando melaço de cana-de-açúcar como fonte de carbono. Os resultados obtidos mostraram que o cultivo da levedura em meio contendo melaço (MC) produziu o mesmo teor de lipídeos totais e carotenoides (16,50% ± 0,68% e 0,053 ± 0,001 mg g-1, respectivamente) quando comparado com o produzido em meio sintéticos (SC) (15,36% ± 1,36% e 0,051 ± 0,001 mg g-1 0,005). Sobre a síntese de ácidos graxos, o cultivo de MC gerou o perfil mais interessante, uma vez que este apresentou um conteúdo majoritário de ácido oleico (74,05%), um composto insaturado com alto valor nutricional. O cultivo conduzido com melaço e suplementação de extrato de levedura (MYEC) não mostrou aumento na produção microbiana de óleos, o que indica que nessa condição prevaleceram outras formas de metabolização do substrato pelas células da levedura, como foi confirmado pelo estudo da cinética microbiana.

Abstract One of the most important classes of nutritional biomolecules is the oleaginous compounds group, which specially includes the oil-lipids, the carotenoids and the fatty acids. These biocompounds present a wide range of industrial applications because their ability to act as an energy source, antioxidants and metabolic agents for the human body. Therefore, the food industry, mainly focusing on food supplementation, is always searching for new sources of them. In this context, the present study evaluated the total lipids, carotenoids and fatty acids simultaneous production by the Rhodotorula mucilaginosa CCT3892 yeast, using residual sugarcane molasses as carbon source. The results obtained demonstrated that the cultivation of yeast in molasses medium (MC) produced the same content of total lipids and carotenoids (16.50% ± 0.68% and 0.053 ± 0.001 mg g-1, respectively) as the obtained from a synthetic medium (SC) (15.36% ± 1.36% and 0.051 ± 0.001 mg g-1 0.005). Concerning the fatty acids biosynthesis, the MC cultivation generated the most interesting profile once it presented a greater content of oleic acid (74.05%), an unsaturated compound with high nutritional value. The cultivation carried out with the molasses and yeast extract supplementation (MYEC) did not provide an improvement in microbial oil production, what indicated that in this condition there was a predominance of others sorts of substrate metabolization by the yeast cells, as confirmed by the microbial kinetics study.

Abstract This study investigates the application of NIR spectroscopy for real-time monitoring of process parameters in alcoholic fermentations. For this purpose, fermentation batches using Saccharomyces cerevisiae were carried out and monitored in situ by an immersed NIRS probe. Samples were collected throughout the fermentations, and concentrations of biomass, glucose, ethanol and glycerin were analyzed by reference methods and multivariate data analyses such as PCA and PLSR. PCA was used to investigate data variability and to select samples for calibration and for external validation sets. A PLSR model for biomass yielded R2 and RMSEP values of 0.99 and 0.276 g.L-1, respectively. For glucose, the carbon source, the PLSR model yielded an R2 of 0.95 and an RMSEP of 7.14 g.L-1. The PLSR model for ethanol was characterized by an R2 of 0.95 and an RMSEP of 0.06 g.L-1. For glycerin, a highly accurate PLSR model with an R2 of 0.98 and an RMSEP of 0.116 g.L-1 was obtained. These results indicate that an in situ NIRS probe is suitable for real-time monitoring of important parameters in alcoholic fermentations.

O cajá (Spondias mombin L. ) é utilizado na fabricação de sorvetes, geléias, polpas, produção de bebidas e consumo in natura. Um dos procedimentos mais importantes para a conservação de alimentos é a secagem, considerando que a maioria dos frutos frescos são constituídos de aproximadamente 80% de água. A secagem de alimentos é utilizada visando basicamente dois aspecto: o fator econômico do transporte e manuseio do produto; o material após seco e triturado é depois reidratado, em níveis desejáveis, para formulação de um novo produto como na fabricação de sorvetes, geléias, de iogurtes, de bebidas e também poderá ser adicionado em massa, biscoitos e outros produtos industrializados. O objetivo deste trabalho foi estudar a cinética de secagem do bagaço de cajá, em secador de bandejas com leito fixo, utilizando um planejamento fatorial composto central. Os fatores avaliados foram: temperatura (55; 65 e 75 ºC), velocidade do ar de entrada no secador (3,2; 4,6 e 6,0 m.s-¹) e espessura da torta na bandeja (0,8; 1,2 e 1,6 cm). A variável resposta considerada foi a umidade do bagaço (b.s). Os resultados mostraram que os efeitos principais e interações foram significativos ao nível de 95% de confiança. A melhor condição foi na temperatura 75 ºC, velocidade de 6,0 m.s-¹ e espessura de 0,8 cm.

The caja (Spondias mombin L.) is used in the manufacture of ice-cream, jams, pulps, beverages being also consumed in natura. One of the most important procedures in food conservation is drying, considering that most fresh fruits contain approximately 80% of water. Food drying is used to obtain two basic aspects: (1) the economic factor; in the shipping and handling of the product; (2) at the manipulation; once dried and grinded, the material is rehydrated, at desirable levels, to formulate a new product as in ice cream, jams, yoghurts and drinks and may also be added to pasta, biscuits and other industrialized products. The aim of this study was to investigate the kinetics of caja bagasse drying in a fixed-bed tray dryer, using central composite factorial planning. The following factors were evaluated: temperature (55, 65 and 75 ºC), dryer inlet air velocity (3.2, 4.6 and 6.0 m.s-1) and cake thickness (0.8, 1.2 and 1.6 cm) where the response of the considered variable was caja bagasse moisture content (b.s.) and the results showed that the main effects and their interactions were significant at a 95% confidence level being the best condition obtained at temperature of 75 ºC, velocity of 6.0 m.s-1 and cake thickness of 0.8 cm.

With the advent of recombinant DNA technology, recombinant protein expression has become an important tool in the study of the structure, function and identification of new proteins, especially those with therapeutic functions. Escherichia coli has been the predominant prokaryote used in genetic engineering studies due to the abundance of information about its metabolism. Despite significant advances in molecular biology and immunology of infections, there are as yet no prophylactic drugs capable of preventing visceral leishmaniasis. It is therefore important to identify specific antigens in order to develop vaccines and diagnostic kits against this disease. The objective of this study was to evaluate the influence of culture medium on the production of eIF antigen from Leishmania chagasi in recombinant Escherichia coli. An induction procedure using IPTG was carried out in a series of trials, to observe the influence of culture medium (2xTY, TB) under expression of the recombinant eIF protein. Results showed that recombinant protein expression was associated to growth and that the highest eIF antigen expression was obtained in the 2xTY medium.