This research is aimed to improve the oxytetracycline production from Streptomyces rimosus. Five relatively high oxytetracycline yielding strains were obtained by nitrosoguanidine mutation of the protoplast of initial oxytetracycline producing strain Streptomyces rimosus JH and then subjected to genome shuffling as parental strains. The protoplasts of the five parental strains were prepared and...

OBJECTIVES In this study we examined the in vitro synergistic effect of baicalin, the flavone constituent of Scutellaria spp., in combinations with oxytetracycline and tetracycline on the growth of Staphylococcus aureus. METHODS The MICs were determined by the broth microdilution method and the effect of combinations was evaluated according to the sum of fractional inhibitory concentration in...

In this study, a simple, sensitive, selective and precise HPLC method is developed for the determination of oxytetracycline in bulk and honey samples. Separation of oxytetracycline was achieved on a Kromosil C18 analytical column (250 mm × 4.6 mm I.D., 5 μm particle size). The mobile phase was a mixture of acetonitrile and water (85:15 v/v) at a flow rate of 1.5 ml/min. The method was linear in...

Oxytetracycline (200 mg/kg body weight,ip) was administered in 0.5 ml of sterile physiological saline for 15 days, resulting in significant increase in serum urea, creatinine and reduction in creatinine clearance. A significant increase in lipid peroxidation markers (TBARS and lipid hydroperoxides) and, decrease in enzymic antioxidants (superoxide dismutase,catalase,glutathione peroxidase and g...

Many farmers in developing countries protect their crops with oxytetracycline and fertilize their farmlands with manure from animals that received this drug as growth promoter. In this study, a tropical soil was exposed to 0.1 mg kg(-1), 1 mg kg(-1), and 10 mg kg(-1) of oxytetracycline for 22 days to evaluate whether this antibiotic alters the capacity of a soil microbial community to metaboliz...

production of oxytetracycline by an isolated strain of streptomyces rimosus from iranian soil was investigated using a special fermentation medium. a comparative study was performed with standard strain ptcc 1144 using the following parameters optimum growth conditions with respect to time, ph, and different amounts of corn steep liquor. surprisingly, the production yield of the wild strain was...

Oxytetracycline is a polyketide antibiotic made by Streptomyces rimosus. From DNA sequencing, the gene product of otcD1 is deduced to function as a bifunctional cyclase/aromatase involved in ring closure of the polyketide backbone. Although otcD1 is contiguous with the ketoreductase gene, they are located an unusually large distance from the genes encoding the "minimal polyketide synthase" of t...

BACKGROUND Chemical pleurodesis is widely recommended in the treatment of refractory pleural effusion or pulmonary air leak of different etiologies. Although several agents have been used, many questions have remained unanswered about their toxicity. Talc is the most commonly used agent for the treatment, with rare, serious complications reported. Oxytetracycline pleurodesis in clinical practic...