Abstract
1. A colorimetric method to determine the activity of TTC reduction in tissue slices of bean embryo was established.
2. The reduction proceeded at constant rate under aerobic condition as well as under anaerobic condition.
3. The reduction rate increased with reaction temperature till 50°C. The pH of surrounding medium influenced the reaction rate slightly.
4. Plasmolysis with sugar solutions depressed the reaction, whereas urea favoured it at high concentration. Deplasmolysis prior to the reaction stimulated the reduction.
5. Plasmolysis with inorganic salt solutions influenced the reduction in different degrees. At the plasmolysing concentrations, anions affected the reaction in the order of the lyotropic series. No serious order was observed among cations.
6. Relationship between the activity of the reaction and site of the enzymes in the cytoplasm and its colloidal state was discussed.
