Abstract：Objective To isolate, purify and identify the secondary metablites from the fermentation broth produced by Bacillus subtilis strain GA21.
Methods Different column chromatographies were used to isolate and purify the secondary metabolites. HR-ESI-MS, 1D-NMR and 2D-NMR were used to analyze the structure of compounds GA21-20 and GA21-26. Agar plating method was used to analyze the inhibition activity of the secondary metabolites against Staphylococcus aureus, Escherichia coli, Pyricularia oryzae and Candida Albican.
Results GA21-20 and GA21-26 were purified and structurally identified as a group of isocoumarin antibiotics. GA21-20 has the same structure with Amicoumacin B, but does not have anti-bacterial and anti-fungus activity. GA21-26 is a new member of isocoumacin antibiotic with the molecular formula of C21H29O7N3 and molecular weight of 435.2, and has anti-fungus activity. GA21-26 inhibits the growth of plant pathogenic fungi Pyricularia oryzae and Candida Albicans at80 μg per paper and 2.5 μg per paper respectively.
Conclusion A series of 3, 4-dihydroisocoumarin can be isolated from the secondary metabolites produced by strain GA21 and more secondary metabolites need to be discovered from the fermentation broth of the strain GA21.
靳婧, 旭格拉?哈布丁, 刘少伟, 郭琳, 蒋忠科, 栾迎春, 李展先, 潘臻, 孙承航. 罗布泊来源胀果甘草根际枯草芽孢杆菌GA21次生代谢产物结构与活性初步研究[J]. 《中国医药生物技术》杂志, 2012, 7(1): 14-19.
JIN Jing, HABDEN Xugela, LIU Shao-Wei, GUO Lin, JIANG Zhong-Ke, LUAN Ying-Chun, LI Zhan-Xian, PAN Zhen, SUN Cheng-Hang. Preliminary study of structures and bioactivities of the secondary metabolites produced by Bacillus subtilis strain GA21. , 2012, 7(1): 14-19.
2012, Vol. 7 
