| Abstract
| - Sodium copper chlorophyllin (SCC), a water-soluble commercial derivative of chlorophyll, has gainedimportance as a food colorant and dietary supplement with apparent chemopreventive activities. Thethermal stability of SCC was studied to assess the potential application of this chlorophyll derivativefor use in thermally processed foods and supplements. Thermal degradation of an aqueous 500ppm SCC solution was monitored between 25 and 100 °C by a loss of absorbance at 627 nm.Decomposition was also followed by reversed phase C18 HPLC with photodiode array detection tomonitor the loss of Cu(II)Chlorin e4, the major component of commercial grade SCC. The rate ofthermal degradation of SCC was found to follow first-order reaction kinetics. HPLC analysis confirmedthe ultraviolet and visible absorbance data and also demonstrated loss of the major SCC component,Cu(II)Chlorin e4, at a rate faster than that of overall SCC. The activation energy was estimated usingthe Arrhenius equation and found to be 13.3 ± 0.8 and 16.0 ± 2.1 kcal/mol for the thermal degradationof SCC and Cu(II)Chlorin e4, respectively. The observed temperature sensitivity of SCC wasdetermined to be similar to that of natural chlorophyll and raises the possibility of color deteriorationwhen used in food products where mild to severe thermal treatment is applied. Furthermore, theimplication of rapid loss of Cu(II)Chlorin e4, a reported bioactive component of SCC, upon heatingmay result in alteration of potential dietary benefits such as antimutagenic and antioxidant activity. Keywords: Sodium copper chlorophyllin; Cu(II)Chlorin e4; thermal degradation; UV−vis spectrophotometry; HPLC
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