Antibacterial Activities of Actinomycetes Isolated from the Soils of Rhizospheric Zones of Pine Trees at Chovar Hill, Kathmandu

  • R. Tuladhar Tamrakar Central Department of Microbiology, Tribhuvan University Kirtipur, Kathmandu

Abstract

Actinomycetes isolated from the rhizospheric zone of pine trees at Chovar Hill, Kathmandu were screened for antibacterial activity. It was found that out of 35 isolates, 11 were active against gram positive bacteria, four against gram negative bacteria and six against both bacteria when analyzed by perpendicular streak method. The test organisms used in the analysis were Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi and Staphylococcus aureus. From the isolates exhibiting antibacterial activity, 14 isolates that performed effective inhibitory activity were selected and upon their identification, employing morphological examination and physiological tests, it was revealed that seven isolates belong to genera of streptomyces, four belong to Micromonospora, two belong to Nocardia and one to Srreptoverticillum. The antibacterial potency of the identified isolates cultured in the liquid medium was determined by agar cup plate assay method using the above test oganisms. Most of the isolates performing activity during screening in agar were found to exhibit activity in the broth culture as well.