Of the many reported applications for xylanase, its use as a food supplement has played an important role for monogastric animals, because it can improve the utilisation of nutrients. The aim of this work was to produce xylanase by extractive fermentation in an aqueous two-phase system using Aspergillus tamarii URM 4634, increasing the scale of production in a bioreactor, partially characterising the xylanase and evaluating its influence on monogastric digestion in vitro. Through extractive fermentation in a bioreactor, xylanase was obtained with an activity of 331.4 U mL(-1) and 72% yield. The xylanase was stable under variable pH and temperature conditions, and it was optimally active at pH 3.6 and 90 °C. Xylanase activity potentiated the simulation of complete monogastric digestion by 6%, and only Mg2+ inhibited its activity. This process provides a system for efficient xylanase production by A. tamarii URM 4634 that has great potential for industrial use.

Protein hydrolysates originating from egg white have already been reported to be bioactive and, among their biological activities, possess the antioxidant property that protects the body from early ageing and diseases linked to oxidation. Therefore, the objective of this work was to evaluate the antioxidant activity of hydrolysates obtained by the hydrolysis of egg HIGHLIGHTS • Is the first report about protease production by Aspergillus avenaceus URM 6706 • Aspergillus avenaceus URM 6706 is from Caatinga, a specific biome of the Brazil • The protease is stable in broad pH range and temperature • Protease had great performance at presence of ions, oxidizing agent and surfactants 2 A.C. Silva; et al.

Os pigmentos Monascus, além de possuírem cores atrativas, possuem alto poder corante, entretanto, podem ser instáveis em temperaturas elevadas e pH extremos. Nesse contexto, alguns métodos alternativos vêm surgindo para favorecer sua estabilidade, como a liofilização. Este estudo buscou avaliar o efeito da liofilização na estabilidade frente à temperatura (50 a 90 ºC) e pH (3 a 8) dos pigmentos de Monascus purpureus CCT 3802 produzidos por fermentação submersa. A estabilidade térmica se baseou na determinação da constante de degradação térmica (Kd), tempo de meia vida (t1/2), energia de ativação (Ea), valor de redução decimal (D), Valor Z e a análise termodinâmica que foram calculados antes e após a liofilização. O extrato bruto apresentou um valor de Kd= 0,232 h-1, t1/2= 3,0 h e valor D = 9,93 h a 90 ºC e valor Z = 31,25 h. Entretanto, o extrato liofilizado apresentou Kd = 0,167 h-1, t1/2= 4,2 h e valor D = 13,84 h a 90 ºC e valor Z = 58,82 h, demonstrando maior estabilidade deste extrato à altas temperaturas. Os resultados obtidos em relação à estabilidade ao pH demonstraram que a liofilização apresentou menor degradação dos pigmentos, com percentual de pigmentos variando de 100 a 96% em 60 min. Portanto, a tecnologia de secagem por liofilização se mostrou uma excelente alternativa para aprimorar a estabilidade dos pigmentos sintetizados por Monascus purpureus CCT 3802.

Enzymes obtained by fermentation processes offer a number of advantages and have been widely researched and

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