The enthalpy of combustion of the samples agree with the previous reports except for the sample GA. The reason for this deviation is not clear. The enthalpy of formation \(({H}_{f}^{o})\) for each sample was calculated using standard heat of formation\({H}_{f}^{o}\left(\text{CO}_{2(g)}\right)=\ -393.51\ kJ/mol\) and\({H}_{f}^{o}\left(H_{2}O_{(l)}\right)=\ -285.83\ kJ/mol\)[24], according to the reactions (5), (6) and (7).
The accuracy of these values \(({H}_{f}^{o})\) is a function of the validity of the molecular formula of the carbohydrate used to represent the B. vulgaris agro-waste which has a direct influence on the accuracy of the heat determination. Environmental factors such as temperature, pH, substrate concentration and presence of toxins have been used extensively to elucidate the feasibility of microbial degradation. Estimation of physical property such as heat capacity and heat of formation will further ascertain the veracity of microorganism in environmental engineering application.