1. School of Medicine and Pharmacy Key Laboratory of Marine Medicine Chinese Ministry of Education Ocean University of China 5 Yushan Road Qingdao 266003 P. R. China
2. Hainan Key Laboratory for Research and Development of Natural Products from Li Folk Medicine Institute of Tropical Bioscience and Biotechnology Chinese Academy of Tropical Agricultural Sciences Haikou 571101 P. R. China
3. Laboratory for Marine Drugs and Bioproducts Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 P. R. China