Suggested Reaction 1.1.3.-

Left

9-Hydroxy-3,5,7,11,13,15,17-octaoxo-nonadecanoyl-[acp]
+O2

Right

3,5,7,9,11,13,15,17-Octaoxo-nonadecanoyl-[acp]
+H2O2

[BiSSCat | GREP ]