Int Microbiol. 2026 Jul 4. doi: 10.1007/s10123-026-00847-8. Online ahead of print.
ABSTRACT
Talaromyces purpurogenus is a filamentous fungus capable of producing red polyketide-like pigments with potential as natural alternatives to synthetic colorants. This study investigated the ecological distribution, phylogenetic diversity, and relative pigment-producing capacity of T. purpurogenus isolates recovered from agricultural soils, decaying fruits, spoiled grains/cereals, and stored feed/food materials. A total of 35 isolates were obtained, with the highest isolation frequencies observed in agricultural soils and spoiled grains/cereals. Molecular identification based on ITS rDNA and β-tubulin sequence similarity supported the assignment of the isolates to T. purpurogenus. Multilocus phylogenetic analysis revealed well-supported intraspecific subclades, suggesting notable genetic diversity among the examined isolates. Pigment production, semi-quantitatively evaluated spectrophotometrically at 500 nm (OD₅₀₀) following ethyl acetate extraction, varied significantly among isolates. Statistical analysis demonstrated a significant association between phylogenetic clustering and relative pigment production (p < 0.001), as well as between ecological origin and pigment production levels (p < 0.01), indicating that pigment-associated phenotypes are influenced by both genetic background and environmental factors. Strain PP05 exhibited the highest relative pigment production and was selected for optimization studies. Experimental analysis showed that pH, temperature, carbon and nitrogen sources, and incubation period significantly affected pigment production (p < 0.001), with maximum relative pigment production recorded at pH 5.0 and 24 °C in sucrose-peptone medium after 7 days. These findings provide an eco-phylogenetic perspective on pigment-associated variability in T. purpurogenus and highlight its relevance for future strain-selection and biotechnological studies.
PMID:42400698 | DOI:10.1007/s10123-026-00847-8
