Extracellular pigment production from Talaromyces purpureogenus under stress conditions and potential of produced pigments as anti-glycation agents

• Stress alters pigment production and composition in Talaromyces purpureogenus • EtOH and H 2 O 2 addition increases red pigment productivity • T. purpureogenus pigments exhibit anti-glycation activity • Fungal pigments show potential as sustainable, functional food dyes Biological pigment production has become increasingly important because of adverse health effects associated with chemical dyes. The fungus Talaromyces purpureogenus has been used to produce extracellular water-soluble red pigments similar to those produced by Monascus . Several studies have investigated Monascus pigment production under certain stress conditions; however, few have examined extracellular pigment production in Talaromyces . Furthermore, little research has been conducted on the use of fungal pigments as functional food dyes. Therefore, we evaluated the ability of T. purpureogenus to withstand abiotic stress in cultivation media and the effects of stress on pigment productivity. Abiotic stress was induced via the addition of sodium chloride (NaCl), sea salts, ethanol (EtOH), and hydrogen peroxide (H 2 O 2 ). Stressful conditions altered pigment production and composition. An increase in yellow-to-red pigment production ratio was observed under saline stress with both NaCl and sea salts. The yield of yellow pigment increased 1.44-fold in the presence of 1% (w/v) NaCl, while the yellow-to-red pigment ratio rose from 1.59 to 3.88 in the presence of 2% (w/v) sea salts. Addition of 1% (v/v) EtOH and 0.5% v/v H 2 O 2 (30% w/w) increased red pigment production by 2.59- and 1.67-fold, respectively. Differences in colourant properties were highlighted using UV-Vis and fluorescence spectroscopic measurements. Partially purified pigments inhibited bovine serum albumin glycation in the presence of ᴅ-ribose, demonstrating their potential to prevent the formation of advanced glycation end products. Overall, these findings demonstrated that stress conditions can improve pigment productivity in T. purpureogenus and highlight the possibility of producing functional food dyes.