Rheological characteristics of Ganoderma applanatum exoploysaccharides

Glucose yeast extract peptone media (GYP) proved to be the most suitable medium for organism growth and exopolysaccharides (EPS) production which recorded 0.320 + 0.01 and 0.1+0.01 (mg/ml) dry weight undershaken and static conditions respectively. Rheological study of Ganoderma applanatum exopolysaccharides indicated that viscosity of each EPS concentrations increased with increased shear rate (S.R) values which confirm the dillatent behavior of the different concentrations of EPS. pH value  has a valuable effect on the rheological pattern of EPS, with best effect at pH5.5. Furthermore, it was found from the results that sucrose addition as carbon source enhanced the (consistency index cP) viscosity of EPS solution while arabinose decreased EPS viscosity. Therefore, EPS of G. applanatum isolated from AlBaha area, Saudi Arabia might have promising applications in field of food and textile industry. Key words: Growing media, exopolysaccharides, rheology, pH and Ganoderma applanatum.