Produção de frutosiltransferase por Rhodotorula sp. / Production of fructosyltransferase by Rhodotorula sp.

AUTOR(ES)
DATA DE PUBLICAÇÃO

2007

RESUMO

The global functional food market is estimated at 33 billion dollars per year and a great number of new functional foods have been introduced continuously to the market. A lot of attention has been given to dietary carbohydrates, in special to the fructooligosaccharides (FOS). FOS present advantageous characteristics such as low calories and stimulating effects to bifid bacterium growth, present in human gut. Fructosyltransferases (FTase) are the enzymes responsible for FOS production. An efficient and economical method for industrial production is immobilization of this enzyme. The production and application of FOS has gained great commercial importance due to its favorable functional properties. The search of new potential sources of fructosyltransferase starts to be of great importance in a market point of view. For this reason, the possibility of fructosyltransferase production, by conducting several batch fermentations with Rhodotorula sp., isolated and selected in the Laboratory of Bioprocess Engineering at FEAUNICAMP was investigated. Fermentations were realized using industrial by-products pretreated with activated carbon. In order to analyze the obtained results, two experimental designs were carried out. Firstly, a Plackett Burman screening design led to election of the most important process variables, followed by a second analysis with a central composite rotatable design which permitted the optimization of the enzyme production. The highest productivity was about 2000 U/L_h. utilizing the following medium composition and conditions: molasses at 60 g/L of total reducing sugars, 70 g/L of corn steep liquor, temperature of 30°C, agitation at 650 rpm, 1.5 vvm of aeration and initial pH 4.5. pHcontrolled fermentations (at pH 4.5, 5, 6 and 7) showed that the pH plays an important role in maintaining high values of enzymatic activity. After reaching a maximum enzyme production, no decrease of enzymatic activity was seen while the pH was kept constant.

ASSUNTO(S)

fructooligosaccharides frutooligossacarideos enzymes batelada simples planejamento experimental enzimas experimental design batch fermentation

Documentos Relacionados