Pigment Production by Pseudofusicoccum sp.: Extract Production, Cytotoxicity Activity, and Diketopiperazines Identified.

Filamentous fungi are among the most commonly used microorganisms for producing various metabolites including dyes. Ensuring the safety of products derived from microorganisms is always essential. In this study, the isolated fungus was identified as Pseudofusicoccum sp., a producer of the burgundy pigment through submerged fermentation. The fungus exhibited enhanced growth and pigment production under yellow light. The extract obtained showed no cytotoxicity in the tested cell lines (HepG2, SCC4, BJ, and MRC-5). Among the compounds isolated and identified through NMR analysis, cyclo(L-Pro-L-Val) and cyclo(L-Leu-L-Pro) (diketopiperazines) had been previously reported in foods and are known to be produced by various organisms, with several beneficial biological activities. This identified fungus represents a promising source of biopigments with a crude extract that is non-cytotoxic. Additionally, the isolated compounds exhibit significant biological properties, such as antibacterial, antifungal, and antioxidant activities, highlighting their potential as natural pigments for use in food products.