FATTY-ACID PATTERNS OF PHOSPHOLIPIDS AND LIPOPOLYSACCHARIDES IN ENVIRONMENTAL-SAMPLES

Fatty acid patterns of phospholipids and lipopolysaccharides were quantitatively determined in six typical environmental samples in order to characterise their microbial community structures. The grassland soil displayed elevated alpha and mid-chain hydroxy fatty acids, and contained a great numbers of methyl branched saturated fatty acids on C2 and C4. The aggregated soil lacked mainly mid-chain hydroxy, dicarborxylic and omega-hydroxy fatty acids, the latter two are indicators of eukaryotes, therefore exhibited enhanced ratio of beta OH fatty acids which symbolise Gram-negative bacteria. The salt marsh lacked Bacillus species, fungi and plants, but contained enhanced proportion of indicators for Desulfovibrio io strains and Gram-negative bacteria by its fatty acid composition. The forest layers showed high percentages of indicators of fungi and extremely low proportions of fatty acids contributed by Gram-negative bacteria. The branched chain saturated fatty acids, indicators for actinomycetes and Gram-positive bacteria increased proportionally with the depth of forest layers.