Fatty Acid Analysis and Soil Microbial Community Analysis

Fatty acid analysis by gas chromatography has been used commercially since the mid-1980s for microbial identification of pure cultures, direct fatty acid analysis, and soil microbial community analysis. The automated peak naming and data analysis system we use was developed by our sister company, MIDI, Inc.

We employ a variety of extraction methods. For non-soil samples, we use:

  • Whole-cell fatty acid (FAME) analysis: We identify fatty acids that are linked to all lipid classes, including those from Sphingolipids (Anaerobes).

For soil microbial community analysis, PLFA is the primary method, then PLFA + NLFA, and finally EL-FAME. A summary of the soil analysis methods we use include:

  • Phospholipid fatty acid (PLFA) analysis: We identify fatty acids that are linked to phospholipids only (those from the "living" microbial biomass).

  • Neutral lipid fatty acid (NLFA) analysis: We identify fatty acids that are linked to triglycerides (fungal storage lipids, including those from arbuscular mycorrhizal fungi) and diglycerides (those from the "dead" microbial biomass).

  • Ester-linked fatty acid (EL-FAME) analysis: We identify fatty acids that are linked to all lipid classes, except those from Sphingolipids (Anaerobes).
We use the Sherlock PLFA Analysis System and a high-throuput extraction protocol for the peak naming and data analysis, co-developed by our sister company, MIDI, Inc. (Buyer & Sasser, 2012)

High-throughput PLFA Method for Soils

Additionally, for bacterial identification, FAME analysis is an effective tool for strain tracking, an advantage over other identification techniques (e.g. MALDI-TOF and 16S rRNA sequencing-based systems).

As a sister company of MIDI, Inc., we have more experience with fatty acid analysis technology and the MIDI Sherlock system than any other lab worldwide.