The fermentative production of oxytetracycline on industrial by-products byStreptomyces rimosus 12907

Three strains ofStreptomyces rimosus were grown on four different media. The one suitable for the production of oxytetracycline byStreptomyces rimosus 12907 was modified by black strap molasses, fodder yeast (40% total protein) and rice bran. The volume of the fermentation medium was scaled up in a 1200-litre fermentor aerated with sterile air obtained from a system used in the purification of air. 850 g crude oxytetracyeline was obtained when the fermented medium (700 litres) was extracted with 1-butanol. This work was carried out in the Laboratories of the Chemical Factories of the Egyptian Sugar anio Distillation Company with the cooperation of the National Research Centre, Dokki, Cairo, Arab Republd of Egypt (A.R.E.).     

The fermentative production of acetone-butanol by Clostridium acetobutylicum.

Fourteen different media were used in the fermentative production of acetone-butanol. The highest total yields were achieved in medium I. Potato starch and soluble starch were suitable as carbon sources. The best concentrations of potato starch and soluble starch were 500.0 and 10.0 g/l, respectively. Peptone was the most favourable nitrogen source. The best concentration of peptone was 4.0 g/l. Calcium carbonate in 3.6 g/l acted as buffering agent in the fermentation process. The best initial pH value of the fermentation medium was 6.0. The optimum temperature was 32--33degreesC. The fermentation process required 120 h to obtain maximum yields of acetone-butanol.