Photosynthetic inhibitors in Eucalyptus grandis

Unlike the G-inhibitors isolated from the leaves of Eucalyptus grandis, synthetic G-inhibitors showed no inhibition of photosynthetic electron transport. These findings indicated that small amounts of impurities present in the natural samples were responsible for the inhibition of photosynthetic electron transport. In support of this, grandinol and homograndinol were isolated from the leaves of E. grandis and were shown to be the active photosynthetic electron transport inhibitory components in the E. grandis preparation of G-inhibitors.