“A 30 ….1 mM CuCl2 suppressed responses to single concentrations of the following sweeteners: …, D-tryptophan, 6-chloro-D-tryptophan, L-valine, glycine , sucrose, maltose, lactose, tetrachloro-galacto-sucrose, glucose, fructose, methyl alpha-D-glucopyranoside, glycerol, …-4'-cyano-3'-(2-2-2-trifluoro acetamido)succinanilic acid, phenethyurea, and stevioside.”
“The responses to glycine HCl and NaCl were slightly suppressed by CuCl2.”