J. Annapurna*, M. Himabindu, Subhakar Ch. and Maanasa Jetty

Microbiology Laboratory, Bioengineering and Environmental Centre,
Indian Institute of Chemical Technology (CSIR), Tarnaka, Hyderabad – 500 007. India.

ABSTRACT

The microwave exposed cultures during 48 hr. accumulated more oxytetracycline (OT) titers which was highest having an antibiotic titre of 380 µg/ml as against 24 hr exposed sample and control with 310 µg/ml of antibiotic titre. There is distinct change in the mode of action of antibiotic, with a clear spheroblast formation at the periphery of the zone of inhibition of the test organism Bacillus cereus as evidenced by scanning electron microscopic studies. The present report represents the first description of the microwave exposure inducible property and as such provides some insight into the stress response as evidenced by the heat shock protein profile and physiologically complex Streptomyces species, which produces oxytetracycline, a secondary metabolite.

Keywords: Oxytetracycline, Heat Shock, Microwave, Streptomyces sp.