Study of levan production by Zymomonas mobilis using regional low-cost carbohydrate sources

The use of alternative regional low-cost substrates has become very interesting because in addition to the ease of acquisition it presents a relatively low cost. In this study using statistical instruments, the exopolysaccharide levan production by the Zymomonas mobilis microorganism was analyzed varying the carbon source (commercial sucrose, molasses and sugar cane syrups) and the fermentation medium constituents. There was a decrease in levan production in the molasses medium (2.533 g L−1) when compared to the commercial sucrose (21.685 g L−1) and syrup (15.456 g L−1) media. Yeast extract and KH2PO4 were significant in the commercial sucrose medium for levan production and in the syrup medium the yeast extract and MgSO4 were significant. Although sugar cane syrup up produced about 28.724% less levan compared to commercial sucrose, biomass production in the syrup was 2.76 times greater than in commercial sucrose (0.857 and 2.366 g L−1) that could justify joint levan and Z. mobilis ATCC 31821 biomass production. Studies are needed on the use of alternative substrates and complexes in biotechnology to assess the composition of these media, avoiding unnecessary supplementation with vitamins and minerals salts, when using the formulations of the mediums defined for the complex mediums.