Attached
Most antibiotics are metabolized incompletely
by patients after administration and enter the municipal
sewage with the patients’ excretion. Therefore, studies
on the biodegradability of some clinically important
drugs can be taken as a very first step of an
environmental risk assessment. The present study reports
the biodegradation of CIP by Lactobacillus gesseri,
Enterobacter sp., Bacillus sp., Bacillus subtilius and
Micrococcus luteus which were isolated as CIP resistance,
non pathogenic bacteria. The presence of antibioticresistant bacteria was identified using the 16s rRNA
sequencing. A 0.5ml of overnight starved bacterial
suspensions was introduced into medium containing CIP at
5 ppm. Triplicate samples were incubated at 280
C with
shaking at 100ppm. A 0.5 ml of subsamples was removed at
2 days interval for a period of 14 days. Samples were
subjected to High Performance Liquid Chromatography
(HPLC) analysis. Fourier Transform Infrared Spectroscopy
(FTIR) analyses were carried out for each sample at the
end of the 14 days to find structures of by-products.
Complete degradation of CIP by L. gasserri was detected at
the end of 14 days of incubation with average degradation
rate of 0.182 ±0.15µg /day. Descending degradation rates
were followed by Enterobacter sp. (0.75 ±0.03 d-1
) and
Bacillus sp. (0.41±0.02d-1
) at 8 and 6 days respectively.
However, clear cut degradation of CIP was not detected for
B.subtilis and Micrococcus luteus respectively. Further,
FTIR spectrum revealed that incubation of L. gesseri,
Enterobacter sp. and Bacillus sp., changed the piperazine
ring and quinolone part in the CIP structure while
degradation occurred.
