title: Antibacterial activity of some actinomycetes from Tamil Nadu, India.
abstract: OBJECTIVE
  To isolate novel actinomycetes and to evaluate their antibacterial activity.
  
  
  METHODS
  Three soil samples were collected from Vengodu (village) in Kanchipuram district, Tamil Nadu, India. Actinomycetes were isolated using serial dilution and plating method on actinomycetes isolation agar.
  
  
  RESULTS
  Totally 35 isolates were obtained on the basis of colony characteristics on actinomycetes isolation agar. All the isolates were screened for antibacterial activity by cross streak method. Medium and optimization of day were done for the potent strains using Nathan's agar well diffusion method. Isolation of bioactive compounds from significant active isolates was done by using different media. The most active isolate VAS 10 was identified as Actinobacterium Loyola PBT VAS 10 (accession No. JF501398) using 16s rRNA sequence method. The hexane, ethyl acetate, dichloromethane and butanol extracts of VAS 10 were tested against bacteria. The maximum antibacterial activity was observed in dichloromethane and ethyl acetate; maximum zones of inhibition were observed against Enterococcus durans. The rRNA secondary structure and the restriction sites of Actinobacterium Loyola VAS 10 were predicted using Genebee and NEBCutter online tools respectively.
  
  
  CONCLUSIONS
  The present study showed that among the isolated actinomycetes, Actinobacterium Loyola PBT VAS 10 (accession No. JF501398) showed good antibacterial activity against the tested bacteria.
authors.affiliation: Division of Microbiology, Entomology Research Institute, Loyola College, Chennai, India-600 034.
authors.forename: Pachaiyappan Saravana
authors.initials: PS
authors.lastname: Kumar
authors.forename: John Poonga Preetam
authors.initials: JP
authors.lastname: Raj
authors.forename: Veeramuthu
authors.initials: V
authors.lastname: Duraipandiyan
authors.forename: Savarimuthu
authors.initials: S
authors.lastname: Ignacimuthu
mesh_terms: D039903:Actinobacteria / Q000737:chemistry* / Q000302:isolation & purification* / Q000502:physiology; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000898:Antibiosis / Q000502:physiology; D001412:Bacillus subtilis / Q000187:drug effects; D021902:Enterobacter aerogenes / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D007194:India; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012988:Soil Microbiology; D013045:Species Specificity; D014736:Vibrio parahaemolyticus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D012336:RNA, Ribosomal, 16S
keywords: Actinobacterium; Antibacterial activity; Solvent extract; VAS10