Isolation and diagnosis of bacteria and fungi from some areas of tikrit and some villages

Abstract

Background: Airborne microorganisms, including bacteria and fungi, contribute to environmental air pollution and may pose health risks, especially in agricultural regions.

Objective: To assess airborne bacterial and fungal contamination in selected areas of Tikrit, including Al-Alam, Al-Bu Ajil, Al-Buhyazaa, and Al-Karaat village.

Methods: A descriptive study was conducted during November and January 2021–2022 using the passive settle plate method. Petri dishes containing Potato Dextrose Agar (PDA) were exposed to air for 15 minutes across sampling sites. After incubation, microbial growth was analyzed. Bacteria were cultured on MacConkey agar and Eosin Methylene Blue (EMB) agar. Gram staining was used for bacterial identification, while Lactophenol cotton blue staining was used for fungal identification.

Results: Fungal contamination was higher than bacterial contamination, with Penicillium spp. predominating in agricultural areas. The highest colony count was observed in Al-Bu Ajil (sample G2.1), with over 96 colonies, approximately two to three times higher than other sites, likely due to favorable environmental conditions such as humidity and temperature. Most bacterial isolates were Gram-negative, mainly Klebsiella spp., which showed growth on MacConkey agar in Tikrit, Al-Alam, and Al-Karaat, indicating environmental adaptability. No bacterial growth was detected in Al-Buhyazaa (sample 3.1 H), possibly due to unfavorable conditions.

Conclusion: Airborne microbial contamination varied across study sites, with higher fungal loads in agricultural areas and widespread presence of Gram-negative bacteria. Environmental factors significantly influence microbial distribution in air.