Table 1. Amino Acid Composition of the Peptidomelanin Acid Hydrolysate Acquired via LC-MS (DNA Labs India, Hyderabad)^a.

	Absolute mass %	Relative mass %
Amino acid	(mean ± SD)	(mean ± SD)
Glycine	7.73 ± 0.82	33.62 ± 0.92
Glutamate**	2.49 ± 0.05	10.85 ± 0.61
Proline	2.45 ± 0.09	10.69 ± 0.46
Alanine	2.39 ± 0.12	10.42 ± 0.27
Aspartate*	2.26 ± 0.19	9.83 ± 0.06
Arginine	1.42 ± 0.10	6.19 ± 0.05
Leucine	0.90 ± 0.02	3.93 ± 0.21
Lysine	0.78 ± 0.07	3.39 ± 0.03
Serine	0.61 ± 0.01	2.67 ± 0.16
Phenylalanine	0.51 ± 0.03	2.23 ± 0.04
Threonine	0.47 ± 0.18	2.03 ± 0.62
Histidine	0.25 ± 0.11	1.08 ± 0.40
Tyrosine	0.21 ± 0.01	0.93 ± 0.03
Valine	0.18 ± 0.01	0.80 ± 0.01
Methionine	0.16 ± 0.01	0.69 ± 0.03
Isoleucine	0.13 ± 0.02	0.55 ± 0.15
Cysteine	0.01 ± 0.00	0.06 ± 0.01
Tryptophan***	0.01 ± 0.00	0.04 ± 0.00
Asparagine*	0.00 ± 0.00	0.01 ± 0.01
Glutamine**	0.00 ± 0.00	0.00 ± 0.00
Total	22.98 ± 1.84	100

^a19 of 20 canonical amino acids were detected in the peptidomelanin acid-hydrolysate. Absolute mass % refers to the mass of each amino acid as a percentage of the total mass of peptidomelanin. The sum total of the absolute mass % of all amino acids is 22.98 ± 1.84%, which is the total % amino acid composition of peptidomelanin. Relative mass % refers to the mass of each amino acid as a percentage of the total mass of all amino acids present. It should be noted that some amino acids cannot be quantified via acid hydrolysis. Amide groups like those found on asparagine* and glutamine** would be converted into carboxyl groups in hot hydrochloric acid, leading to an over-representation of aspartate* and glutamate**. Tryptophan*** is readily degraded under acid hydrolytic conditions and would therefore be underrepresented.