Molecular Identification and Characterization of Cefalexin-Degrading Bacterial Isolates

The widespread and uncontrolled use of antibiotics in human and veterinary medicine, as well as agriculture, has led to the accumulation of antibiotic residues in various ecosystems, raising global concerns over environmental and public health. Cefalexin, a first-generation cephalosporin antibiotic, is frequently detected in wastewater, soil, and surface waters, where it contributes to the emergence and proliferation of antibiotic-resistant bacteria and resistance genes. In recent years, bioremediation using naturally occurring microbial populations has been recognized as a promising strategy to eliminate such contaminants. The present study focuses on the isolation, morphological, biochemical, and molecular characterization of cefalexin-degrading bacterial isolates from soil environments. A total of twelve cefalexin-tolerant bacterial strains were isolated and subjected to detailed screening. The study evaluated their growth behavior under various pH and temperature conditions, biochemical traits, and sugar fermentation profiles, and further identified potent strains via 16S rRNA gene sequencing. The findings revealed significant physiological diversity and robust adaptability among isolates, supporting their potential application in bioremediation strategies for mitigating environmental antibiotic contamination.