1. School of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin, P.R. China,
2. Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, P.R. China,
3. School of Pharmacy, University of Health and Allied Sciences, Ho, Ghana, and
4. Department of Pharmaceutical Chemistry, School of Pharmacy, College of Health Sciences, University of Ghana, Legon, Ghana