Figure 6.
HPL-chromatograms of analytical experiments with Spathiphyllum wallisii leaf material showing the oxidation of artificially added NCC 4epi to oxidized NCCs 5epi and 6epi, and YCC 7, under different experimental conditions. Solutions containing the NCC 4epi were first purged with specified gases (O2, air, N2, CO/air 1/1 (v/v)), and then mixed with deoxygenated Sp. wallisii leaf material. After storage under the indicated conditions for half an hour in the dark at ambient temperature the slurries were centrifuged and supernatants analyzed by HPLC. Formation of oxidized NCCs (6epi and 5epi), as well as of YCC 7, was monitored by UV/Vis detection at 320 nm. Experiments are shown (top to bottom) from purging with O2, with air, with N2, and with CO/air 1:1 (v/v), and which indicate decreasing activity, in this order.