Abstract
Yeast extract is widely known to have the elicitor activity. In order to assess the activity of the brewers’ yeast extract, we quantified the accumulation of glyceollin in soybean cotyledons treated with it. The glyceollin isomers were accumulated in those cotyledons, therefore it also had elicitor responsiveness.
It was fractionated by ultrafiltration membranes, and the each fraction was assessed by the cotyledon bioassay. Large molecules over 100 kDa had the high activity. This fraction was mainly composed of glucans and mannans. Of the polysaccharides tested, glucans have the much higher activity. These results suggest that glucans are one of the elicitors of the brewers’ yeast extract and induce plant disease resistance. Further identification and purification of elicitors, the mechanism of elicitation are in progress.
