[Changes in water state and soluble protein contents of wampee axes during inducing desiccation tolerance by sucrose preculture].

Progressively increasing sucrose concentration of culture medium could increase desiccation tolerance of wampee [Clausena lansium (Lour.) Skeels] axes. The changes in water state and soluble proteins of axes during acquirement of desiccation tolerance were measured by differential scanning calorimeter (DSC) and SDS-PAGE. The results showed that the cooling and heating thermograms of sucrose-precultured axes were similar to those of the control; but there was a stepwise change in the heating thermograms of sucrose-precultured axes, implying that vitrification might occur in axes. Unfreezable water amounts of wampee axes were measured, the results showed that amounts of unfreezable water of sucrose-precultured axes and control were 25.4% and 25.9% (by the linear regression equation method), or 24.3% and 23.7% (by the heat of ice fusion method) respectively, which were not significantly different. The soluble protein content of sucrose-precultured axes was 68% higher than the control, and SDS-PAGE showed that a 20-kD protein markedly increased in content.