Pullulan production from co-culture method

Pullulan is an -glucan consisting mainly of maltotriose units interconnected via ? 1,6 linkages. Pullulan is an extracellular polysaccharide produced by the polymorphic fungus Aureobasidium pullulans.It can be extruded easily as films that are biodegradable, is resistant to oils and grease, unaffected by temperature, impermeable to oxygen, nontoxic and therefore edible. Pullulan is a suitable polysaccharide due to its good-film-forming properties for production of edible protective films. Besides its applications in the edible film in dustry, pullulan has numerous applications in food, cosmetics and pharmacological industries. In this study, pullulan from Aureobasidium pullulans and Kluyveromyces marxianus strains was produced and characterized. The strains was tested for determination of temperature, pH range and inoculum concentration for growth and pullulan production on plate. NH4CI, (NH4)2SO4, calcium nitrate and urea were tested to determine the best nitrogen source. NH4CI was determined as the best nitrogen source. DNS method was used in determining the amount of pullulan. The optimum fermentation conditions were found to be incubation period of 3 days, substrate concentration of %5 and incubation temperature at 28°C pH 7.5. Key Words: Microbial polysaccharide, Pullulan, Aureobasidium pullulans, Kluyveromyces marxianus, Edible film