Triterpenoids constitute major bioactive components in Inonotus obliquus. Among them, inotodiol stands out for its diverse biological activities, most notably its antitumor effects, which highlight its significant potential for cancer treatment. However, its biosynthetic pathway remains unclear. In this study, a rice-based medium solid-state fermentation strategy was employed to cultivate I. obliquus and obtain inotodiol, ergosterol, and lanosterol with yields of 7.33, 14.61, and 108.65 mg/kg, respectively. To investigate the genes involved in triterpenoid biosynthesis, transcriptomic analysis was conducted on mycelia collected at different cultivation time points (5 and 10 d). The expression levels of triterpenoid-related genes exhibited an increasing trend, which was further validated by qPCR. Furthermore, comparative genomic analysis of triterpene modified genes identified potential modifying enzymes, including cytochrome P450s, short-chain dehydrogenases, and ergosterol biosynthesis-related genes. These findings provide crucial insights into triterpenoid biosynthesis in I. obliquus, and offer valuable candidate genes for further investigation of its biosynthetic pathways.
Duan, Y., Wu, J., Kawagishi, H., Liu, C., Duan, Y., Wu, J., Kawagishi, H., & Liu, C. (2025). Transcriptome analysis at different times reveals candidate genes of triterpenoid biosynthesis in Inonotus obliquus under rice medium. Panfungi, 1(1). https://doi.org/10.48130/panfungi-0025-0002