Biological Degradation of Chlorophyll in a System Using Bell Peppers (Capsicum frutescens)

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Abstract
SUMMARY– A degradation system was developed based on the incorporation of radioactive chlorophyll into a ripening bell pepper carpel.Pure chlorophyll a in aqueous triton X‐100 injected into green bell peppers (Capsicum frutescens) variety 035 was degraded up to 50% by the end of ripening, versus a control in buffer pH 5.4 not exceeding 7% loss in 2 weeks. Variety and stage of ripeness affected the amount of degradation.Labeled chlorophyll a with a specific activity of 7 to 8 × 105 dpm/mg was then prepared from young wheat plants, fed 14Cob and injected in amounts of 0.2 to 0.3 mg. The distribution of activity in pepper extracts after pigment degradation was evaluated. The acetone water extract remaining after transfer of lipid material to petroleum ether acquired activity within 2 days of injection, but the amount remains fairly constant for 12 days. The activity of the extraction residue, and of an 80% ethanol extract thereof, increased throughout the experiment. The residue containing increasing amounts of protein had the largest amount of radioactivity of the three fractions at the conclusion of the experiment.Preliminary chromatography did not yield isolated radioactive products.Extracts of pepper show no activity when substituted for soybean extract in a system containing chlorophyll and linoleic acid.The degradation of chlorophyll by ripening bell peppers provides a tool for further studies for degradation in a physiological system.Labeling facilitates isolation, identification, and establishment of origin of small amounts of breakdown products.