NPN + Amines + Amides
+ AA + NH3 + Peptides
Peptides (> 9 AA) +
Proteins
Protein soluble in ND
A
B1
B2*
C
Lanzas et al. (2007)
ADIN
NDIN - ADIN
Soluble in
BPB
Insoluble
in BPB
NDIN
A
B1
B2*
C
Fox et al. (2004)
B3
Non amino-N
Amino-N
Extensins
Lignin-N, tannins-N, Maillard prod.
Examples
Globulins
Albumins
Fraction A and B1 are soluble in Borate Phosphate Buffer. Fraction B2 precipitates with Trichloroacetic Acid (TCA); usually 9 AA long.