Dissolved organic carbon in seawater

Simply on the basis of the normal composition of marine organisms, we would expect proteins and peptides to be normal constituents of the dissolved organic carbon in seawater. While free amino acids might be expected as products of enzymic hydrolysis of proteins, the rapid uptake of these compounds by bacteria would lead us to expect that free amino acids would normally constitute a minor part of the dissolved organic pool. This is precisely what we do find the concentration of free amino acids seldom exceeds 150 xg/l in the open ocean. It would be expected that the concentration of combined amino acids would be many times as great. There have been relatively few measurements of proteins and peptides, and most of the measurements were obtained by measuring the free amino acids before and after a hydrolysis step. Representative methods of this type have been described [245-259]. Since these methods are basically free amino acid methods, they will be discussed next in conjunction with those methods. 

In this connection, Gershey et al. [ 58 ], in a detailed study, have compared results obtained for dissolved organic carbon in seawater using the evaporation-... 

Gershey, R.M., M.D. MacKinnon, P.J. leB Williams, and R.M. Moore. 1979. Comparison of three oxidation methods used for the analysis of the dissolved organic carbon in seawater. Marine Chemistry 7 289-306. 

Sharp, J.H., R. Benner, L. Bennett, C.A. Carlson, S.E. Fitzwater, E.T. Peltzer, and L.M. Tupas. 1995. Analyses of dissolved organic carbon in seawater The JGOFS EQPAC methods... 

Sugimura, Y., and Y. Suzuki. 1988. A high temperature catalytic oxidation method for the determination of non-volatile dissolved organic carbon in seawater by direct injection of a liquid sample. Marine Chemistry 41 105-131. 

Only 10% of the dissolved organic carbon in seawater has been characterized on a molecular level. About 5 to 23% of this DOC can be isolated from seawater by adsorption onto a nonionic macroporous resin fiallowed by elution with an alkaline solution. 

An approach such as that suggested for the re-examination of the molecular weight distribution of dissolved organic carbon in seawater (Carlson et al., 1985) has been successfully adapted to evaluate the performance of ultrafiltration in the study of radionuclide speciation ... 

Wang, J.T., Z.B. Zhang, and L.S. Liu. 1997. Determination of dissolved organic carbon in seawater using UV/persulphate method and HTCO method. Chin. J. Oceanol. Limnol. 15 25-31. 

Solomon CM, Lessard EJ, Keil RG, Foy MS (2003) Characterization of extracellular polymers of Phaeocystis glob-osa and P. antarctica. Mar Ecol Prog Ser 250 81-89 Sugimura Y, Suzuki Y (1988) A high temperature catalytic oxidation method for the determination of non-volatile dissolved organic carbon in seawater by direct injection of a liquid sample. Mar Chem 24 105-131 Sunda WG, Huntsman SA (1995) Iron uptake and growth limitation in oceanic and coastal phytoplankton. Mar Chem 50 189-206... 

Sharp, J. H., Benner, R., Bennett, L., Carlson, C. A., Dow, R., and Fitzwater, S. E. (1993). Re-evaluation of high temperature combustion and chemical oxidation measurements of dissolved organic carbon in seawater. Limnol. Oceanogr. 38, 1774—1782. 

Aluwihare L. L, Repeta D. J., and Chen R. F. (1997) A major biopolymeiic component to dissolved organic carbon in seawater. Aatere 387, 166-167. 

Starikova, N.D., 1970. Vertical distribution patterns of dissolved organic carbon in seawater and interstitial solutions. Oceanology, 10 796—807. 

Williams, P.M., 1969. The determination of dissolved organic carbon in seawater a comparison of two methods. Limnol. Oceanogr., 14 297—298. 

Wang JT, Zhao WH, Zhang ZB (2000b) Adsorption of natural dissolved organic carbon in seawater on needle ferric mineral. Oceanol Limnol Sin 31(3) 309-313 (in Chinese with English abstract)... 

Spyres G, Nimmo M, Worsfold PJ, Achterberg EP, and Miller AEJ (2000) Determination of dissolved organic carbon in seawater using high temperature catalytic oxidation techniques. Trac-Trends in Analytical Chemistry 19 498-506. 

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