Pioneered by Microbial Insights founder Dr. D.C. White, PLFA analysis is used to quantify total viable biomass and provide a general profile of the microbial community. Phospholipid fatty acids (PLFA) are a main component of the cell membrane (“the skin”) of all microbes.
PLFA are extracted directly from a sample removing the need to grow the bacteria and eliminating biases associated with traditional approaches (e.g., plate counts and MPNs).
PLFA decomposes quickly upon cell death, so quantification of total PLFA in a sample represents the concentration of viable (living) cells. Results reported as cells/mL, cells/g, etc.
Some types of microorganisms produce specific types or “signature” PLFA biomarkers. While not specific like DNA based techniques, the relative proportions of these groups of PLFA biomarkers provide a general profile of the microbial community highlighting groups such as sulfate reducing bacteria (SRB), anaerobic metal reducers, fermenters, and fungi.
Proteobacteria modify specific PLFA biomarkers during periods of slow growth or in response to environmental stress providing an indicator of their physiological status and health.
Analysis can be performed on almost any type of sample (water, solids, corrosion coupons, swabs, pig sediment, scrapings, and others).
Microbial Insights has been performing PLFA on field samples to evaluate MIC since 1992.
HOW TO USE PLFA:
Use PLFA to quantify total living biomass and produce a general profile of the microbial community composition.
Use PLFA to help answer…
- What is the total viable biomass concentration?
- Do system conditions support microbial growth?
- Was the biocide effective?
- Did viable biomass decrease in response to treatment?
- Is viable biomass rebounding?
- What is the overall microbial community composition?
- Has the microbial community changed?
- Did percentages of anaerobic microorganisms increase?