Production of 1-(β-d-ribofuranosyl)-1,2,4-triazole through solid-state fermentation with Purpureocillium lavendulum DQWM-G4.

1-(β-d-Ribofuranosyl)-1,2,4-triazole (RTA) is a nucleotide analog of 1,2,4-triazole that demonstrates broad-spectrum antiviral activity. It is currently the approved drug for treating chronic hepatitis E virus (HEV) infections. However, the production of RTA relies predominantly on chemical synthesis and extraction from plants and animals, with no report of microbial metabolic production. This study introduces a novel approach to producing RTA via solid-state fermentation (SSF) using Purpureocillium lavendulum DQWM-G4, with rice as the substrate. The chemical structure of RTA was elucidated through 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. Fermentation conditions for producing RTA were optimized by investigating substrate type, temperature, and duration. Under optimized conditions, SSF with P. lavendulum DQWM-G4 on rice at 20 °C for 60 d yielded RTA at a high concentration of 3.46 ± 0.16 mg/g. This paper represents the first report on microbial production of RTA, offering an alternative to chemical synthesis and natural extraction.