In vitro susceptibility comparisons and recommendations for oxolinic acid

Area of Science:

• Microbiology
• Pharmacology
• Analytical Chemistry

Background:

• Accurate antimicrobial susceptibility testing is crucial for effective treatment.
• Oxolinic acid is an antibiotic requiring standardized testing methods.
• Existing disk diffusion methods may need optimization for specific antimicrobial agents.

Purpose of the Study:

• To determine the optimal disk content of oxolinic acid for reliable susceptibility testing.
• To evaluate the performance of different oxolinic acid disk concentrations (1, 2, and 5 mug).
• To ensure the accuracy and authenticity of oxolinic acid concentrations used in testing.

Main Methods:

• Minimal inhibitory concentration (MIC) and disk diffusion susceptibility studies were conducted.
• Regression curve analyses were performed using disks with varying oxolinic acid content.
• Ultraviolet (UV) spectral analysis was employed to verify drug authenticity and concentration.

Main Results:

• The 5-mug oxolinic acid disk demonstrated superior performance in susceptibility testing compared to 1-mug and 2-mug disks.
• Regression analysis supported the efficacy of the 5-mug disk for standardized testing.
• UV spectral analysis confirmed the accurate concentration and authenticity of the oxolinic acid solutions.

Conclusions:

• A 5-mug disk is recommended for oxolinic acid disk susceptibility testing.
• This standardized approach enhances the reliability of susceptibility testing results.
• The findings contribute to improved antimicrobial stewardship and patient care through accurate diagnostics.