The van Krevelen diagrams showing the alignment of the molecular formulae in each sample, for
the whole, unfractionated sample, the
acid-insoluble portions, as well as the
hydrophilic C18 filtrate and
hydrophobic C18 retentate. Data points are colored according to heteroatom composition, where black points are CHO-only, and red, blue, and green points are CHON, CHOS, and CHONS formulae, respectively. Regions for specific biomolecular compound classes are given, and the averaged mass spectral calculations are shown in Table 3.