Studies on the Respiration Rate of Banana Fruit Based on Enzyme Kinetics

Aerobic respiration rates of banana as a function of O2 and CO2 concentration at 21°C in closed respirometer is described based on enzyme kinetics. Parameters of three types of Michaelis-Menten equation based on type of inhibition were considered. A Microsoft Visual Basic computer simulation package (MM-Calculator) was developed to calculate parameters. This program estimated regression parameters and the sum of squared errors between observed and predicted values of respiration rates. The proposed software was used for experimental data to find proper Michaelis-Menten parameters. The uncompetitive form was found as the best type of inhibition for respiration rate of banana. In addition simulated surface plots for the respiration rates of banana at 21°C with respect to different atmospheres of O2 and CO2 using the model constants were presented. Based on simulation curves RO2 and RCO2 decreased by decreasing the O2 and increasing the CO2 levels and influence of CO2 concentration on respiratory quotient (RQ) did not observed. Therefore, using both of low O2 and high CO2 atmospheres decreased the respiration of banana. In addition, the RQ remained stable and close to unity. © 2010 Friends Science Publishers