Photo-Oxidative Protection of Chlorophyll a in C-Phycocyanin Aqueous Medium

In this study, potential protection of chlorophyll from illumination and oxidation-induced decomposition has been examined using C-phycocyanin (C-PC) aqueous medium. Photo-oxidation resistance of chlorophyll was monitored in various aqueous media using ultraviolet-visible spectroscopy and direct-infusion atmospheric pressure chemical ionization mass spectrometry analysis. The spectroscopy results showed that chlorophyll in C-PC medium experienced the lowest rate of conversion to its derivatives; thus, it was demonstrated that chlorophyll was mostly intact in the C-PC medium. Furthermore, the C-PC treated with chlorophyll showed the lowest concentrations of malondialdehyde, and chlorophyll in C-PC medium did not cause serious damage to human liver cells in vitro after intensive illumination. Therefore, we propose a new method of protecting chlorophyll from photodegradation and oxidation using C-PC aqueous medium.