Phenotypic characterization of Nocardia spp. isolated from Iran soil microflora

Document Type : Original Article


1 Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran

2 Department of Bacteriology and Virology, School of Medicine, Alborz University of medical Sciences, Karaj, Iran


Aims: The present study was conducted to identify Nocardia spp. from Iran soil by various phenotypic tests. Materials and Methods: A total of 300 soil samples were collected of five different geographical regions in Iran. Nocardia isolation was performed by paraffin baiting technique. The colonies that were similar to be Nocardia spp. were stained with Gram, partially acid fast and acid-fast. Phenotypic tests were used for identification of Nocardia spp. Results: After analysis of phenotypic tests, the identified species are as follow: Nocardia asteroides (49.12%), Nocardia cyriacigeorgica (24.56%), Nocardia otitidiscaviarum (38.6%), N. asteroides complex (19.29%), Nocardia africana (3.5%), and Nocardia pseudobrasiliensisNocardia coubleaeNocardia ignorata (each species; 1.75%). In this study, some of isolates (8.77%) remained undetected. Conclusion: Due to great number of Nocardia spp., high similarities among biochemical characteristics of species and the variability of some these characters, a wide range of biochemical tests should be used to identify Nocardia spp. to gain more accurate results.


Volume 4, June
June 2015
Pages 1-5
  • Receive Date: 30 January 2023
  • Accept Date: 30 January 2023