The cultivation strategy of enhancing triterpenoid production in submerged cultures of Antrodia cinnamomea by adding monoterpenes

• Triterpenoids are the biologically active components found in A. cinnamomea.
• How to increase the production of triterpenoids warranted detailed study.
• Limonene proves to be the most effective in triterpenoid production.
• The content of crude triterpenoid showed a thirteen-fold increase.
• GC analysis shows that monoterpene added was metabolized into other compounds.

Antrodia cinnamomea has long been used as a folk remedy; recently, it has become a very expensive medicinal mushroom in Taiwan. Triterpenoids are considered to be among the most biologically active components found in A. cinnamomea. The aim of this research was to investigate the feasibility of enhancing triterpenoid production in shake flask cultures of A. cinnamomea by adding various types of monoterpenes. The results demonstrated that a monoterpene ethanol solution was inhibitory in regard to mycelia growth; an appropriate time for their addition was determined to be on day 7. Of the various monoterpenes tested, limonene proved to be the most effective in enhancing polyphenol and triterpenoid production. A 1% (v/v) addition of limonene ethanol solution was found to be the most appropriate level; at this level, the content of crude triterpenoid rose to the highest level of 33.93 mg/g DW, for a three-fold increase. In contrast, total polyphenol content achieved the highest concentration of 11.02 mg/g DW at an adding level of 2% (v/v) limonene and 1% (v/v) ethanol, representing a nearly two-fold increase compared with the control group. Moreover, this study also demonstrates that monoterpene added into the media had been absorbed into the mycelia of A. cinnamomea, and triterpenoids could be one of the metabolic derivatives.