Abstract

INFLUENCE OF GAMMA-RADIATION ON THIRD AND FOURTH GENERATION CEPHALOSPORIN ANTIBIOTICS

Mervat Ali Mohammed Abo-State*, Mohammed Hisham Yassin and Marwa Mohammed El-Shora

ABSTRACT

A total number of 160 pharmaceutical samples of four antibiotic groups were collected, and microbial load was counted by surface plate method in the term of CFU/ml. Total contaminated samples with bacteria and/or fungi were (46) samples with a percentage of (28.7%) where (64) fungal isolates and a single bacterial isolate were detected. Three fungal isolates, which represented the predominant fungal isolates, were selected and identified by 18S rRNA for investigating the effect of gamma irradiation as a sterilization method. The dose response curve of the three fungal isolates showed that 6.0 and 7.0 KGy reduced their viable count completely. Three contaminated antibiotics (cefotaxime, cefoperazone and cefepime) were irradiated to determine the sterilization dose. After irradiation, no or slight changes were observed in their odor, clarity, solubility in water, pH and their forms. However, mild changes in their color were detected. The dose 25 KGy was an efficient dose for complete sterilization and could not degrade the chemical structure of the samples as determined by HPLC, which indicated the stability of the drugs after sterilization by gamma irradiation. The results of microbiological potency showed that the antibacterial activity generally remained unaffected or slightly decreased for the three antibiotics.

Keywords: Antibiotics, Microbial load, 18S rRNA, Sterilization, Gamma Radiation.