Amino acids and monosaccharides in sediments in the vicinity of an urban sewer

Changes in the composition and distribution of organic matter from the urban sewer of the City of Marseilles (France) were studied in superficial sediments (16 stations) and in suspended particulate matter collected by sewer sediment traps. Sugar and amino acid compositions were assayed by HPLC (high pressure liquid chromatography) analysis in parallel with determination of hydrolysis kinetics and the insoluble to soluble ratios. The organic matter from the sewage outlet and in sediments located near the outlet was more rapidly hydrolysed and exhibited lower I/S ratios than that of marine sediments. The monosaccharide composition and particularly the glucose/ribose, glucose/fucose and mannose/fucose ratios which varied strongly with increasing distance from the sewage outlet may constitute a fingerprint of the terrigenous matter in the marine environment. The variations in the amino acid spectra were comparatively smaller. Four major forms were dominant in the outlet itself, the superficial sediments and particle-traps and exhibited significant changes. Changes in the nitrogenous fraction could be attributed to changes in some minor or non-protein amino acids such as methionine and methionine sulfoxide.