| dc.description.abstract | Antibiotics were a major tool utilized by the health care industry to fight bacterial infection;
however, bacteria were highly adaptable creature and were capable of developing resistance to
antibiotic. Consequently, decades of antibiotic use, or rather misuse, have resulted resistance to
many modern antibiotics. This antibiotic resistance could cause significant danger and suffering
for many people with common bacterial infection, those once easily treated with antibiotics. For
several decades, studies on selection and dissemination of antibiotic resistance have focused
mainly on clinically relevant species. However, recently, many investigators have speculated that
commercial bacteria including lactic acid bacteria (LAB) might act as reservoirs of antibiotic
resistance genes similar to those found in human pathogens. The main threat associated with
these bacteria was that they could transfer resistance genes to pathogenic bacteria. Gene
conferring resistance to Erythromycin, Tetracycline, Vancomycin have been detected in
Lactobacillus species isolated food products. A number of initiatives have been recently launched
by various organizations across the globe to address the biosafety concerns of starter
microorganism in horizontal transfer of antibiotic resistance genes to intestinal microorganism
and food associated pathogenic bacteria.
The aim of this study was to examine the transfer of Tetracycline, Kanamycin, Ampicillin and
Erythromycin resistance determinants from Lactobacillus acidophilus isolated from market drug
products and Lactobacillus helveticus isolated from fermented food. The transfer was performed by
using an in vitro mating method (conjugation). The conjugation experiments were carried out
with the donors and recipients using the filter mating method. The recipients were Methicillin -
sensitive- Staphylococcus aureus (MSSA) and Bacillus subtilis. Using disc diffusion test, all the
donors and recipients were tested the sensitivity to Tetracycline, Kanamycin, Ampicillin and
Erythromycin before mating.
Antibiotic susceptibility profiles were determined for Lactobacillus acidophilus and Lactobacillus
helveticus. Lactobacillus acidophilus was resistant to Kanamycin, Erythromycin, Ampicilllin,
Tetracycline at high concentrations (> 512µg/ml). In other hand, the MICs (Minimum inhibitory
concentration) of Lactobacillus helveticus to Tetracycline, Ampicillin, Erythromycin were 16µg/ml,
32µg/ml, 32µg/ml respectively. Lactobacillus helveticus was resistant to Kanamycin at
concentration higher than 512µg/ml. The MIC (Minimum inhibitory concentration) of Methicillin
- sensitive- Staphylococcus aureus (MSSA) and Bacillus subtilis to Ampicilin were at 2µg/ml. The
MICs of Staphylococcus aureus and Bacillus subtillis to Tetracycline were at 2µg/ml and 1µg/ml respectively. The MICs of Staphylococcus aureus and Bacillus subtillis to Erythromycin were at
64µg/ml and 32µg/ml respectively and to Kanamycin were at 128µg/ml. All transconjugated
Staphylococcus aureus and Bacillus subtillis were confirmed by disc diffusion test and agarose gel electrophoresis.
Impacts of these transfers were examined in the light of food or drug safety and potential effects on public health application. | en_US |
