Evaluation of four types of inhibition for modelling the influence of carbon dioxide on oxygen consumption of fruits and vegetables
Herman W. Peppelenbos and Johan van 't Leven
Postharvest Biology and Technology Vol: 7 Issue: 1-2 page 27-40.
1996
บทคัดย่อ
High carbon dioxide (CO2) concentrations can reduce the oxygen (O2) consumption rate of a number of fruits and vegetables. This reduction can be modelled by four types of inhibition in an enzyme kinetics model: (1) the competitive type; (2) the uncompetitive type; (3) a combination of both previous types; and (4) the non-competitive type. These different types of inhibition were tested for describing the CO2 influence on O2 consumption using experimental data supplemented with data from literature. The gas exchange rates of apples (cv. Golden Delicious and Elstar), asparagus, broccoli, mungbean sprouts and cut chicory were measured under a wide range of O2 and CO2 concentrations. With the range of CO2 concentrations used, no influence was found on gas exchange rates of apples. There was a clear influence of high CO2 on the gas exchange rates of the other produce. A good estimation of O2 consumption could be obtained with the inhibition models. This supports the use of Michaelis-Menten kinetics for modelling O2 consumption. Depending on the product the statistical analysis gave good results for the competitive and the uncompetitive type of inhibition. Based on gas exchange data only, no distinction between the competitive and uncompetitive type of inhibition could be made. It suggests the simultaneous existence of both types of inhibition. The idea is that the combined inhibition equation is most closely related to what is actually occurring in plant tissues. However, for reasons of simplicity the non-competitive type of inhibition is preferred, showing similar results to the combined inhibition, and giving good results for all the products tested.