Targeted Isolation of Indole Alkaloids from Streptomyces sp. CT37.
Four compounds (1-4) were isolated from the extracts of Streptomyces sp. CT37 using bioassay in conjunction with mass spectrometric molecular networking (MN) driven isolation. Their complete structures were established by high-resolution electrospray ionization mass spectrometry (HR-ESIMS), and 1D and 2D nuclear magnetic resonance (NMR) data. Legonimide 1 was identified as a new alkaloid containing a rare linear imide motif in its structure, while compounds 2-4 were already known and their structures were elucidated as 1H-indole-3-carbaldehyde, actinopolymorphol B, (2R,3R)-1-phenylbutane-2,3-diol, respectively. The biosynthetic pathways of 1-4 were proposed based on the reported biogenesis of indole alkaloids in literature. Bioactivity tests for 1 and 2 revealed moderate growth inhibition activity against Candida albicans ATCC 10231 with MIC95 values of 21.54 µg/mL and 11.47 µg/mL, respectively.
['Fang|Qing|Q|0000-0002-8479-5482', 'Maglangit|Fleurdeliz|F|0000-0002-0159-8337', 'Mugat|Morgane|M|', 'Urwald|Caroline|C|', 'Kyeremeh|Kwaku|K|0000-0002-3644-9497', 'Deng|Hai|H|0000-0002-0047-0622']
D000935:Antifungal Agents D002176:Candida albicans D026121:Indole Alkaloids D019906:Nuclear Magnetic Resonance, Biomolecular D021241:Spectrometry, Mass, Electrospray Ionization D013302:Streptomyces
indole alkaloids Streptomyces sp. CT37 legonimide imide antifungal natural products