1. State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao 266237, Shandong, P. R. China.
2. Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, Shandong, P. R. China.
3. Laboratory of Marine Drugs and Biological Products, Pilot National Laboratory for Marine Science and Technology, 168 Weihai Road, Qingdao 266237, Shandong, P. R. China.