Alternative Carbon Sources from Sugar Cane Process for Submerged Cultivation of Cunninghamella bertholletiae to Produce Chitosan

A mucoralean strain of Cunninghamella bertholletiae was used to evaluate the influence of culture medium on chitosan production. In the traditional medium for the growth of mucoralean strains, constituted of yeast extract, peptone, and D-glucose as carbon source, the highest chitosan yield found was 55 mg/g of dry mycelia in a 72-hour submerged culture. Regional substrates from sugar cane process in Northeast Brazil, as sugar cane juice and molasses, which were supplemented with 0.3 % yeast extract, were used as economic substrates to produce chitosan. The optimal production of chitosan was found in sugar cane juice medium, yielding 128 mg/g of dry mycelia in batch flasks at 28 degree C. This condition did not need high concentration of sugar cane and gave a good yield of chitosan produced within 48 h (580 mg per L of medium). Molasses did not show to be a good carbon source for chitosan production.