Influência da fonte de carbono na produção de pigmento por talaromyces minioluteus

Abstract

Color is one of the fundamental attributes observed by consumers when purchasing a product. For this reason, several industrial sectors, including food, textiles, cosmetics and pharmaceuticals have begun to invest on compounds that give color and make their products more attractive. Pigments are substances that can be used to enhance and / or give color to a product. In the food industries dyes are widely used in processed foods. These color-conferring additives may be obtained from natural or artificial sources. Nowadays, there is a greater demand for natural dyes because they cause less damage to human health when compared to synthetic colorants. Many microorganisms are able to produce natural pigments of different shades of color, and fungi are having greater prominence for this production. Thus, the main objective of this study was to evaluate different carbon sources in the production of a red pigment by Talaromyces minioluteus in submerged fermentations. The substrates studied were glucose, maltose, glycerol and starch. Fermentations were carried out using four culture media, and in three of them only the carbon source was different: A1RDP1, containing starch, G2 containing glycerol and G3 containing glucose. The fourth medium evaluated was ISP2, containing maltose and glucose. ISP2 is a culture medium described in the literature for production of pigment by T. minioluteus and it was used in this study for comparision with the other media evaluated. The results showed that the highest cell concentration, of 6.04 g/L, was obtained in the ISP2 medium with a maximum specific velocity of 0.069 h-1. It was observed that the fungus achieved higher biomass concentrations in fermentations containing glucose. Pigment production was higher in G2 medium, 5.23 AU/L, with substrate conversion factor in product of 2.15 AU/g. It was observed the begining of pigment production at the end of microbial growth phase, behavior characteristic of secondary metabolite. The reduction in pH and/or a possible repression by the high concentration of glucose may have interfered in the production of pigment by T. minioluteus in G3 medium.