Isolation and Identification of Nocardia spp. from the local soils in diyala province

Abstract

Background: Nocardia spp. belongs to the family Nocardiaceae , are obligatory aerobic, Gram-positive ,non-spore forming, and non-motile ,actinomycete that form filamentous branched cells normally are saprophytes of soil, Nocardia is a rare bacterial opportunistic known for its ability to cause a wide range of clinical diseases in humans and animal                         Objective:To using phenotypic methods from soil samples of Diyala province and study  resistance of to some antibiotic.

Patients and Methods: Collected ( 50 ) soil samples from the various regions of diyala province  The samples included various ecosystems, rural areas and urban areas and culture of samples on the media trypton soya agar which containing 5μg / mL tetracycline, 50μg / ml nystatin and 5% NaCl, and diagnosed according to colonial characteristics microscopic examination, biochemical tests isolates were selected to measure their resistance to some of,   the antibiotic.

Results: In the rural area had the highest positive growth. 15samples (60%) showed positive growth and 10 samples (40%).showed negative growth in as for the urban area, only two samples (8%) showed positive growth and 23 samples (92%) showed negative growth of bacterial, In this study,isolation  different types of Nocardia spp. from soil in different areas of diyala province, and used trypton soya agar (TSA) medium containing two antibiotics tetracycline and nystatin, It was the highest percentage of antibiotic resistance in against antibiotic Tobramycin which reached (38.40%) while  was the lowest percentage resistance in the antibiotic Gentamicin which reached (15.30%).

Conclusion: Due to pathogenicity and species diversity of Nocardia, using phenotypic tests are essential for identification of Nocardia species. Isolation and identification of Nocardia spp. from soil of different regions can help to enhance our understanding of epidemiological and ecological of the pathogenic Nocardia species. The isolation of species  resistance to antibiotic   means that they have a predisposition to the pathogenesis of the human.