Changes in Soluble-N in Forest and Pasture Soils after Repeated Applications of Tannins and Related Phenolic Compounds

Figure 1

Chemical structures for (a) (+)-catechin (CAT), (b) gallic acid (GA), (c) methyl gallate (MG), (d) sorghum procyanidin (SOR), (e) β-1,2,3,4,6-penta-o-galloyl-d-glucose (PGG), and (f) tannic acid (TA). The structure shown for tannic acid is a representative molecule for tannic acid, an imprecisely defined mixture of galloyl esters [44]. Figure redrawn from [34].