Regular articleBiosynthesis of 4-acetylantroquinonol B in Antrodia cinnamomea via a pathway related to coenzyme Q synthesis

- Synthesis of benzoic moiety of 4-acetylantroquibobol B is from shikimate pathway.
- Synthesis of isoprenoid side chain of 4-acetylantroquinonol B is from mevalonate pathway.
- 4-acetylantroquinonol B might be a metabolic product of coenzyme Q.

The biosynthesis pathway for production of 4-acetylantroquinonol B (4-AAQB) by Antrodia cinnamomea was investigated by adding various precursors to the culture medium. Adding 4-hydroxybenzoic acid (4-HBA) significantly increased the production of 4-AAQB. Since 4-HBA is an intermediate of the shikimate pathway and 4-AAQB and coenzyme Q (CoQ) are similar in structure, we suspected that the pathway for producing 4-AAQB was closely related to the biosynthesis of CoQ. Since the isoprenoid chain of CoQ is synthesized via the mevalonate pathway, we added oleic acid to the culture medium and confirmed that the addition significantly increased the production of 4-AAQB. Furthermore, adding coenzyme Q0 into the fermentation broth was found to be the most effective way to increase the production of 4-AAQB. We suspect that coenzyme Q0 forms CoQ, after which CoQ is converted to 4-AAQB via unknown steps. The increase in 4-AAQB production due to the addition of CoQ10 further demonstrated that the biosynthesis pathway of 4-AAQB from A. cinnamomea is closely related to CoQ.