Overview
CEN ISO/TS 29843-1:2014 (identical to ISO/TS 29843-1:2010) is a technical specification for assessing soil quality by determining soil microbial diversity using an extended lipid-based analytical approach. The standard specifies a method to extract and quantify both phospholipid fatty acids (PLFA) and phospholipid ether lipids (PLEL) from soils. PLFA/PLEL profiling provides a quantitative measure of viable microbial biomass and a phenotypic fingerprint for taxonomic differentiation within complex soil microbial communities.
Key Topics
- Scope: Defines an extended extraction and analysis method for both PLFA and PLEL; Part 2 of the series covers a simpler PLFA-only extraction.
- Sampling guidance: Refers to ISO 10381-6 for collection, handling and storage of soil intended for microbiological and biomass analyses.
- Extraction principle: Lipids are extracted using the Bligh and Dyer procedure and separated on a silica (si-) column.
- Transformations and separations:
- Mild alkaline hydrolysis to convert phospholipids to fatty acid methyl esters (FAME).
- Acidic methylation for PLEL conversion and specific cleavage of ether bonds (e.g., hydroiodic acid, HI, and subsequent reductive steps) as described in the text.
- Use of solid-phase extraction (SPE) columns (NH, SCX and others) to fractionate saturated (SATFA), mono-unsaturated (MUFA), poly-unsaturated (PUFA), hydroxy-substituted (PLOH) and non-ester-linked fatty acids.
- Derivatization procedures (e.g., TMSI, DMDS) and GC/MS measurement for identification and quantification.
- Measurement & calculation: Procedures for GC/MS-based identification and calculation of PLFA/PLEL fractions to infer microbial composition and physiological state.
Applications
- Environmental and soil quality assessments that require reliable measures of microbial biomass and community composition.
- Soil ecology and agronomy studies tracking microbial responses to land use, pollution, remediation, fertilization, or climate-related stress.
- Environmental monitoring and research laboratories needing standardized, reproducible PLFA/PLEL analysis.
- Complementary use alongside molecular/genetic methods for a combined phenotypic and genotypic view of soil microbial diversity.
Related Standards (if applicable)
- ISO/TS 29843-2 - Simple PLFA extraction method (PLFA-only).
- ISO 10381-6 - Guidance on soil sampling, handling and storage for microbiological assessments.
Keywords: soil quality, microbial diversity, PLFA, PLEL, phospholipid fatty acid analysis, lipid extraction, Bligh and Dyer, GC/MS, ISO/TS 29843-1, CEN ISO/TS 29843-1.