Cultivo de Chlorella sorokiniana em vinhaça de cana-de-açúcar clarificada e suas aplicações biotecnológicas

Abstract

Microalgae represent one of the most promising sources of new products and applications, with considerable advantages over traditional raw materials. This reinforces the relevance of carrying out studies that evaluate alternative means of cultivation for the production of microalgae, since with the increase in the production of microalgae, the prospecting of their products for biotechnological applications also increases. Thus, the objective of the present work was to evaluate the development of Chlorella sorokiniana in an alternative medium based on clarified sugarcane vinasse (Saccharum officinarum) and the production of biodiesel and biopolymer films from microalgal biomass. In order to carry out microalgal cultivation in vinasse, clarification was necessary to reduce color and turbidity. As an alternative product, Moringa oleifera seed + glass filter was efficient in clarifying the vinasse with a higher percentage of color and turbidity reduction obtained using 30 gL-1 of seed, with 68.92% and 78.78% reduction, respectively. The optimal density values were verified for microalgae grown in diluted vinasse and supplemented with NPK fertilizer. It was also possible to obtain a functional relationship by linear regression, for the three microalgal quantification techniques: cell density, optical density and dry biomass, making it plausible to quantify the microalgae through a technique and transform such values through the equations generated by linear regression. As for the applications of microalgal biomass, the ethyl esters produced through ethyl transesterification in situ of the Chlorella sorokiniana biomass met most quality control standards. The production of films by the casting method with microalgae C. sorokiniana, gelatin and glycerol, demonstrated excellent characteristics for food packaging. The films proved to be a barrier at all concentrations of microalgal biomass evaluated for the development of microorganisms Pseudomonas aeruginosa, Escherichia coli, Staphylococcus epidermidis, Salmonella typhimurium.