Pigment production by filamentous fungi on agro-industrial byproducts: an eco-friendly alternative.

The search for new sources of natural pigments has increased, mainly because of the toxic effects caused by synthetic dyes used in food, pharmaceutical, textile, and cosmetic industries. Fungi provide a readily available alternative source of natural pigments. In this context, the fungi Penicillium chrysogenum IFL1 and IFL2, Fusarium graminearum IFL3, Monascus purpureus NRRL 1992, and Penicillium vasconiae IFL4 were selected as pigments producers. The fungal identification was performed using ITS and part of the β-tubulin gene sequencing. Almost all fungi were able to grow and produce water-soluble pigments on agro-industrial residues, with the exception of P. vasconiae that produced pigments only on potato dextrose broth. The production of yellow pigments was predominant and the two strains of P. chrysogenum were the largest producers. In addition, the production of pigments and mycotoxins were evaluated in potato dextrose agar using TOF-MS and TOF-MS/MS. Metabolites as roquefortine C, chrysogine were found in both extracts of P. chrysogenum, as well fusarenone X, diacetoxyscirpenol, and neosolaniol in F. graminearum extract. In the M. purpureus extract, the pigments monascorubrin, rubropunctatin, and the mycotoxin citrinin were found. The crude filtrates have potential to be used in the textile industry; nevertheless, additional pigment purification is required for food and pharmaceutical applications.