Use of Operacional Cycles and Different Substrates in the Production of Succinoglycan by Agrobacterium Radiobacter Nbrc 12665 Cells Free and Immobilized in Loofa Sponge

Abstract

ResumoSuccinoglycan is a soluble exopolysaccharide synthesized by bacteria, composed of glucose monomers, galactose and succinic acid, connected by β-linkages. It is a thickening agent with broad potential application in the food, pharmaceutical and chemical industries. The objective of this research was to evaluate the production operational cycles of succinoglycan obtained from Agrobacterium radiobacter NBRC 12665 free and immobilized in loofa sponge (Luffa cylindrica), using the substrates lactose and sugar cane molasses. To produce succinoglycan, the microorganism was inoculated onto pre inoculum (g/L): sucrose (20), yeast extract (5) and peptone (5). After 72 h incubation, cells were transferred to production medium in erlenmeyer flasks containing 100 ml of medium varying the carbon source (g/L): lactose or sugar cane molasses (7.5) KH2PO4 (1), MgSO4 (0.25), (NH4) 2HPO4 (1), trace elements solution (10 mL), pH 7.0. The solution of trace elements in 100 mL of 0.1N HCl contained: FeSO4.7H2O (0.5 g), MnSO4.H20 (0.2), ZnCl2 (0.1), CoCl2.6H2O (0.1). The incubation in the production medium occurred for 8 days at 30 °C and 180 rpm. The operational cycles were evaluated based on 8-day cycles. At the end of each cycle, the free cells and loofa sponge containing immobilized cells were transferred to a new production medium. The