1. Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province Sichuan Industrial Institute of Antibiotics Chengdu University 610106 Chengdu People's Republic of China
2. State Key Laboratory of Biotherapy and Cancer Center West China Hospital Sichuan University 610041 Chengdu Sichuan People's Republic of China
3. College of Food and Biological Engineering Chengdu University 610106 Chengdu People's Republic of China
4. Graduate School of Pharmaceutical Sciences Tohoku University 980-8578 Sendai Japan