A modified procedure for the identification of anaerobic bacteria by high performance liquid chromatography--quantitative analysis of short-chain fatty acids.

We have developed a new rapid method for analysing volatile and non-volatile short-chain fatty acids using high-performance liquid chromatography. Within 50 min, 22 fatty acids in a standard mixture could be detected in a single chromatographic run. The fatty acids released by anaerobic bacteria in the culture media were ether-extracted and analysed with an Aminex HPX-87H column. Using a microprocessor-controlled chromatography unit, a quantitative analysis of the fatty acids produced in bacterial cultures was possible. Resolution, rapidity and sensitivity were improved as compared to previous methods by using an eluent of 5% acetonitrile in 0.01 N H2SO4 and changing the column temperature to 35 degrees C.