Low Molecular Fatty Acids in the Marine Sediments of Eutrophic Coastal Regions

Abstract

Analytical procedure using a High Performance Liquid Chromatography (HPLC) for the simultaneous determination of volatile and non-volatile fatty acids in marine sediments was examin-ed. The fatty acids were extracted from marine sediments by modified Miyoshi's method. Using Shimadzu gel SCR-101H column on HPLC system, low molecular fatty acids were identified clearly.
The above procedure for the fatty acìds analyses was applied to the sediments of Uranouchi Inlet, Kochi Prefecture. Acetate, formate, propionate, and lactate were detected. Acetate was found in the highest concentration (7.1-29.6μmol/g dry sediment), followed by formate (2.5-11.0μmol/g dry sediment). Only trace amount of propinate was found regardless of season and depth of sediments, while lactate was detected only in the surface sediments during warmer seasons. No fatty acids were detected in the interstitial water. In general, the concentration of fatty acids in the sediments decreased with increasing depth. The concentration of fatty acids was closely correlated with that of carbohydrates in the sediments.