Anti-acne effects of Oriental herb extracts: a novel screening method to select anti-acne agents.

The acne-therapeutic effects of Oriental herb extracts were investigated in terms of antichemotactic effect on polymorphonuclear leucocytes, antilipogenic actions, antibacterial activity against Propionibacterium acnes and resistance induction potency in the bacteria. The ethanol extract (0.01%) of Angelica dahurica markedly suppressed neutrophil chemotaxis, comparable to the effect of erythromycin (0.01%), whereas a strong antilipogenic effect was obtained with rhizoma coptidis (Coptis chinensis) extract (0.01%), leading to a higher efficacy than that of retinoic acid (0.01%). Interestingly, only Glycyrrhiza glabra showed a remarkable antibacterial activity against P. acnes, resulting in negligible induction of resistance, in comparison with a marked development of resistance in the bacteria treated with erythromycin. We suggest that an appropriate formulation containing A. dahurica, rhizoma coptidis and G. glabra could be helpful for the prevention and treatment of acne lesions.