Unsaturated fatty acid promotes the production of triterpenoids in submerged fermentation of Sanghuangporus baumii

Sanghuangporus species are precious edible and medicinal fungi that are traditionally used in Asian countries. Triterpenoids, the major bioactive constituents of Sanghuangporus spp. are currently receiving a lot of attention from the scientific community due to their potent pharmacological activities. However, very few reports have been conducted about the possibility of adjusting the fermentation conditions to increase the triterpenoids yield from certain fungi such as Sanghuangporus baumii . In this study, we examined the effects of four different extracts from mulberry shavings on the production of triterpenoids and traced the major components from the effective extracts by GC-MS to provide a reference for further exploration of the triterpenoids synthetic mechanism. It was found that unsaturated fatty acids significantly promoted the production of triterpenoids. The results suggested a direct correlation between the degree of unsaturation of fatty acid and the triterpenoids yield. The best stimulatory additive was linolenic acid . It increased the triterpenoids yield to 573 mg/L, which was 2.53 times higher than the control. This study not only showed that addition of mulberry shavings extract was an efficient fermentation protocol to improve the triterpenoids yield of S. baumii , but it also highlighted the importance of fatty acid content in the production of triterpenoids.