Feasiblity of the Optical Density (OD) in The Determination of the Microalgal Biomass using Palm Oil Mill Effluent (POME) as Medium
Microalgal biotechnology has attracted intense research interests in the past decade, and relevant topics of microalgal application in different fields have been extensively explored. Plotting the microalgae growth profile vs culture time period is the intuitive way to help understand the growth performance. Estimation of the microalgal biomass concentration by plotting the standard curve of optical density (OD) at certain wavelength is a rapid and common approach. However, the accuracy of this method might be affected by wavelength, microorganism morphology and culture medium compositions. In this study, the standard curve was generated from the biomass concentration of the microalgal strain Chlorella cultivated in diluted palm oil mill effluent (POME) against OD at 750 nm. The average errors of lag phase, exponential phase and stationary phase, as well as that of the entire culture period, were 9.59%, 8.12%, 3.25% and 6.86%, respectively. The results indicate that it is practical and feasible to use OD to determine the biomass concentration when the microalgae grow in POME medium.