Comparação da Produção de levana por Zymomonas mobilis e Bacillus velezensis Utilizando Carboidratos de Baixo Custo e Caracterização por Espectrofotometria

Abstract

Levan is an exopolysaccharide obtained through the transfructosylation of sucrose
molecules from microbial cultures, with various applications in the food,
pharmaceutical, and cosmetic industries. This study compared the levan production by
Zymomonas mobilis and Bacillus velezensis, incorporating low-cost carbohydrates into
the culture medium, such as palm juice and sugarcane broth, aiming to reduce
production costs. The experimental process included the incubation of microbial inocula
in control culture media and media supplemented with 20% of previously sterilized
palm juice and/or sugarcane broth, incubated at 30°C under agitation at 150 rpm for
forty-eight hours, followed by extraction and quantification of the biopolymer through
centrifugation and precipitation with ethanol. The obtained product was subjected to
drying in an oven at 50°C to obtain the dry weight; then, the weight was measured, the
material was ground, and it was sent for spectrophotometric analysis. The results of
biopolymer production under each condition were tabulated, and statistical analyses
were performed using GraphPad Prism software and Tukey’s multiple comparison test,
considering p<0.05 as statistically significant. Based on the statistical data, Bacillus
velezensis produced approximately three times more levan compared to Zymomonas
mobilis. Spectroscopic analysis revealed that the produced biopolymers exhibited
characteristic peaks of commercial levan, demonstrating their potential for industrial
applications. These findings highlight Bacillus velezensis as a promising source for
more economical and sustainable levan production.