Análise dos parâmetros cinéticos para produção de levana por Zymomonas mobilis utilizando fermentação submersa

Abstract

Levan is an exopolysaccharide synthesized by several microorganisms during fermentation of a culture medium containing sucrose, yeast extract and minerals. This biopolymer has applications in the food segment as stabilizers, thickeners, as carriers for flavor and fragrances, as well as in the pharmaceutical segment as a hypocholesterolemic agent and for exhibiting antitumor activity. This work aimed to analyze the kinetic parameters for levan production. The microorganism used was Zymomonas mobilis CCT 4494, incubated in a synthetic medium containing 200.0 g L-1 of sucrose, in a rotary shaker at 200 rpm and 30°C. Samples were taken every 24h, during a period of 96h, in order to determine variations of pH, biomass, reducing sugar, total reducing sugar and levan formation. It was observed that yields of biomass and synthesized biopolymer in 24h were superior to those obtained in 48, 72 and 96h of fermentation.