1. Key Laboratory of Food Nutrition and Functional Food of Hainan Province School of Food Science and Engineering Hainan University Haikou 570228 P. R. China
2. Tropical Crops Genetic Resources Institute Chinese Academy of Tropical Agricultural Science Haikou 570100 P. R. China
3. Key Laboratory of Biomaterials of Guangdong Higher Education Institutes Guangdong Provincial Engineering and Technological Research Center for Drug Carrier Development Department of Biomedical Engineering Jinan University Guangzhou 510632 P. R. China