Amino acids and carbohydrates disappear rapidly in recent marine sediments. Most of the organic matter exists as a high-molecular weight, insoluble polymer which has properties similar to humic acids. Glucose and amino acids react rapidly at neutral pH in the laboratory by the Maillard reaction, to produce a polymer that has many properties common to natural humic acids.

Both form gels that bind large quantities of water. They have comparable elemental compositions. The synthetic reaction produces a polymer with a wide molecular weight range extending to very high values similar to humic acids. They react rapidly with added amino acids. Both give a similar electron spin resonance spectrum. Degradation of the natural and synthetic humic acids by methylation, chlorination, and mild oxidation yields a similar suite of low-molecular-weight, chlorinated organic acids.

Carbohydrate-amino acid-reaction products are likely precursors of part of the polymeric organic matter in recent sediments.

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