Abstract
5-O-methylcyanidin 3-glucoside was isorated from Egeria densa. When detached leaves were incubated in sucrose solution under the light, both anthocyanin synthesis and chlorophyll degradation were induced simultaneously. This system may be regarded as one of model system to elucidate the mechanism of "autumnal coloration." When detached etiolated leaves were incubated in 0.6 M sucrose solution, all the cells were plasmolyzed, in some of which the protoplasts were divided into nearly equal halves within a cell. Anthocyanin was synthesized only in nucleated halves. This result indicated that nucleus were required for anthocyanin formation. When detached leaves were irradiated partially with UV-light and incubated in distilled water, anthocyanin was synthesized in whole leaves. These results suggested the some signal factor(s) inducing for anthocyanin formation might transmit in a leaf. When detached leaves were incubated with sectioned stems in distilled water, anthocyanin synthesis was induced, suggesting that some signal molecule(s) was released from sectioned stems in water acting for detached leaves. We are going to identify and purify the signal molecules from sectioned stems.
