Method development and validation for the quantification of organic acids in microbial samples using anionic exchange...

Area of Science:

• Metabolomics
• Analytical Chemistry
• Microbiology

Background:

• Organic acids are vital for cellular metabolism and understanding regulatory processes.
• Quantifying organic acids aids in studying metabolic dynamics, especially under environmental stress.
• Existing methods for organic acid extraction and analysis are limited and require validation.

Purpose of the Study:

• To develop and validate a robust method for organic acid extraction and quantification from microbial samples.
• To assess the method's performance for a range of aromatic and aliphatic organic acids.
• To demonstrate the method's applicability in real biological samples.

Main Methods:

• Solid-phase extraction using a strong anionic exchange cartridge.
• Gas chromatography-mass spectrometric (GC-MS) analysis.
• Comprehensive method validation including recovery, detection limits, and regression analysis.

Main Results:

• High recoveries (100-111%) for 12 out of 15 tested organic acids.
• Low detection limits ranging from 3 to 272 ng/mL.
• Successful application to cell extracts of Escherichia coli and Prorocentrum minimum.

Conclusions:

• The developed method is effective for quantifying a broad spectrum of organic acids in microbial samples.
• The method provides reliable data for metabolic studies, particularly in environmental microbiology.
• Limitations exist for specific aliphatic acids with complex functional groups.