Isolation and structural elucidation of abietic acid as the main adulterant in an herbal drug for the treatment of psoriasis

An herbal drug for the treatment of psoriasis showed severe clinical adverse reactions. The main component of adulterant was isolated from the drug and its chemical structure was elucidated as abietic acid using NMR, HR–MS, and HPLC–DAD–MS. Although abietic acid had ever been used in clinical study for the treatment of psoriasis, it is not an approved drug. Its adulteration is very dangerous for the patients.

► The main component of adulterant was isolated from an herbal drug.
► Its chemical structure was elucidated as abietic acid.
► The adulteration of abietic acid is dangerous for the patients.