Production of Red Pigments by a Newly Isolated Talaromyces aurantiacus Strain with LED Stimulation for Screen Printing.

Microbial pigments have been widely applied to printing in food, textile, and paper industries as a sustainable alternative to synthetic dyes. Herein, we isolated a novel Talaromyces aurantiacus strain with a strong ability to produce red pigments. We further studied pigment production conditions, stability, screen printing application, and bioactivities. Our results showed that sucrose was a favourable carbon source and the addition of l-histidine significantly enhanced the production of red pigments. Pigment production was strictly photo-regulated with effective wavelengths around 450 nm (blue light). We mixed the red pigments with cellulosic materials and explored their application potentials for screen printing on paper, cotton fabrics, and polymeric carriers. The printing density was significantly improved from 0.3 to 0.7 by overlay printing. T. aurantiacus pigments could be stably stored at pH 5-11, temperature - 10 to 70 °C, and redox potential - 200 to 300 mV. Moreover, the stable ranges were extended to pH 1-11 and temperature over 100 °C after screen-printed on paper. The red pigments exhibited antioxidant activity towards 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (IC50 10.4 mg L-1 in solution). Our results further indicated the red pigments by T. aurantiacus was environmentally friendly based on acetylcholinesterase activity assay. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-022-01008-x. © Association of Microbiologists of India 2022.