Succinoglycan production by solid-state fermentation with Agrobacterium tumefaciens

Succinoglycan was produced by cultivating Agrobacterium tumefaciens on vari ous solid substrates, including agar medium, spent malt grains, ivory nut s havings. and grated carrots, impregnated with a nutrient solution. Fermenta tions were performed on a laboratory scale, both under static conditions an d with agitation, using bottles and a prototype horizontal bioreactor. Seve ral fermentation parameters were examined and optimized, including carbon a nd nitrogen composition, water content and layer thickness of the substrate . The yields and rheological properties of the polymers obtained under diff erent fermentation conditions were compared. The highest succinoglycan yiel d was achieved in static cultivation, reaching 42 g/l of impregnating solut ion, corresponding to 30 g/kg of wet substrate. The polymer production in t he horizontal bioreactor was faster, but the final yield was lower (29 g/l of impregnating solution).