“In-depth studies revealed that Cu(II) catalyzed hydrolysis of PG to benzylpenicilloic acid (PA) and oxidized PA to yield phenylacetamide and other products.”
“When benzylpenicillin (i.e., penicillin G (PG)) was exposed to Cu(II) ion at an equal molar ratio and pH 7, degradation of PG occurred rapidly in the oxygen-rich solution but gradually slowed down to a halt in the oxygen-limited solution.”