Structure of Copper Chlorophyll Analogues in the Chewing Gum Product.

Abstract

Multiple copper chlorophyll analogues were detected in the chewing gum product containing the copper chlorophyll dye using a HPLC apparatus with photodiode array detection. The main components among these analogues were assumed to be 10-hydroxy copper chlorophyll a and b by IR, FAB/mass and NMR spectrometry. Since these copper chlorophyll analogues were main components in the commercial food additive dye, "copper chlorophyll", it was clear that these analogues in the chewing gum product were carried over from this food additive. The 10-hydroxy pheophytins, which are precursors of these copper chlorophyll analogues, were detected from the extract of silkworm excreta, the original material of this dye. These copper chlorophyll analogues were possibly produced by the metalation reaction between the copper and the 10-hydroxy pheophytins which might be generated from the oxidation of pheophytins, like "allomerization reaction", during the process of the synthesis of the original material and its storage. It is possible that these analogues have already been the main components in the original dye.