Demethyltetracycline biosynthesis by streptomyces aureofaciens sub-species viridulaus as influenced by medium composition

The influence of different nutritional compounds on demethyltetracycline by Streptomyces aureofaciens subspecies viridulaus was examined. Of the variety of carbon sources, nitrogen and phosphorus compounds tested; fructose, sodium nitrate and sodium dihydrogen phosphate supported the highest demethyltetracycline production. The addition of ferrous sulfate and nicotinamide [as trace element and vitamin, respectively] stimulated the biosynthesis of the antibiotic. In the majority of cases, the biomass yield ran parallel with the antibiotic production

Biosynthesis of demethyltetracycline by a strain of streptomyces

Streptomyces aureofaciens sub-species viridulaus [isolate No. MN 27] was found to produce a yellowish orange pigment. This pigment was extracted from the fermentation medium by chloroform at neutral pH [pH 7], chromatographically purified and obtained as orange powder. The purified pigmented substance exhibits a strong antimicrobial activity towards Gram positive and Gram negative bacteria [MIC =200, 50, 5, 100, 35 ug/ml against B. Subtilis, B. Megaterium, B. Cereus, Athrobacter simplex, and E. coli, respectively]. The physicochemical characteristics of the purified substance were investigated and accordingly the present antibiotic pigment was identified as a new antibiotic belonging to tetracycline group of antibiotics having indicator properties for which the name demethyltetracycline was suggested