Hongoquercins, new antibacterial agents from the fungus LL-23G227: fermentation and biological activity.
Two new antibiotics, hongoquercins A and B, were isolated from fermentation extracts of the unidentified fungus LL-23G227. In the optimum medium, titers of the A and B components reached approximately 2.1 g/liter and 0.02 g/liter, respectively. The optimum temperature for antibiotic production was approximately 22 degrees C. Growth was delayed at 15 degrees C but appeared to reach higher levels than was observed at 22 degrees C. Addition of dextrose to growth media increased hongoquercin B production. Hongoquercin A exhibited moderate activity against Gram-positive bacteria. Mechanistic studies conducted in an E. coli imp strain suggested membrane damage as the primary mode of bactericidal action. These compounds also lysed human red blood cells, suggesting a similar mode of action on eukaryotic cells.
Abbanat
D A
DA
Natural Products Microbiology, Wyeth-Ayerst Research, Pearl River, New York 10965, USA.
Singh
M P
MP
Greenstein
M
M
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D004912:Erythrocytes / Q000187:drug effects; D005285:Fermentation; D006801:Humans; D008826:Microbial Sensitivity Tests; D012717:Sesquiterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D013329:Structure-Activity Relationship
D000900:Anti-Bacterial Agents; D012717:Sesquiterpenes; C114155:hongoquercin A; C114156:hongoquercin B