Ieodoglucomide C and Ieodoglycolipid, New Glycolipids from a Marine-Derived Bacterium Bacillus licheniformis 09IDYM23

Chemical examination of the ethyl acetate extract from the fermentation broth of the marine-derived bacterium Bacillus licheniformis resulted in the isolation of two new glycolipids, ieodoglucomide C (1) and ieodoglycolipid (2). The structural characterization of 1 and 2 was achieved by extensive spectroscopic evidence, including 2D NMR experiments. A combination of chemical derivatization techniques followed by NMR studies, LC-MS data analysis and a literature review was deployed for the establishment of the stereo-configurations of 1 and 2. Compounds 1 and 2 exhibited good antibiotic properties against Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Salmonella typhi, Escherichia coli and Pseudomonas aeruginosa with MICs ranging from 0.01 to 0.05 μM. Furthermore, the antifungal activity of 1 and 2 was evaluated against plant pathogenic fungi Aspergillus niger, Rhizoctonia solani, Botrytis cinerea and Colletotrichum acutatum as well as the human pathogen Candida albicans. Compounds 1 and 2 inhibited the mycelial growth of these pathogens with MIC values of 0.03-0.05 μM, revealing that these compounds are good candidates for the development of new fungicides.