The respiration and anaerobic fermentation of tea leaf and their relationship to tea fermentation

Abstract

The R.Q. for fresh tea-leaf was close to 1 and fell on carbohydrate impoverishment. Rate of respiration, but not oxidase activity, was depressed by starvation in darkness. Respiration and tea-fermentation required [image]/100 HCN for maximum inhibition. Tea oxidase-substrate systems had the same cyanide sensitivity. The low cyanide sensitivity of plant oxidases in general might be due to the presence of other organic Fe compounds in the tissue which compete with the oxidase system for the cyanide. The CO inhibition of the tea oxidase was reversed by light. This, and the wide range of substrates oxidised, suggests that the tea oxidase is a cytochrome oxidase. Anaerobic fermentation was demonstrated in tea leaf after cyanide inhibition or in an atmosphere of N2. Extensive damage to the tissue almost completely destroyed its ability to undergo anaerobic fermentation. As dehy-drogenase activity was not affected to the same extent, the effect of injury to the tissues was evidently to inactivate the coenzymes concerned in carbohydrate oxidation.