The investigation of compositional and structural characteristics of natural marine organic matter: a review

The natural marine Organic Matter (OM) is a complex mixture of carbohydrates, lipids and proteins present in seawater and sediments, able to affect many processes occurring in the marine environment such as the biochemical cycles of marine nutrients and living organisms. As the complexity of environmental studies concerning OM composition requires the application of accurate analytical methods, the aim of this review is the discussion of the most used and updated methods for OM characterisation, including all the analytical steps from sample preparation to the final instrumental analysis by means of spectroscopic and chromatographic techniques. Recent developments on the structural characteristics of OM are also reported.