화학공학소재연구정보센터
Bioresource Technology, Vol.143, 623-631, 2013
Detection of algal lipid accumulation due to nitrogen limitation via dielectric spectroscopy of Chlamydomonas reinhardtii suspensions in a coaxial transmission line sample cell
In this study, dielectric characterization of algae cell suspensions was used to detect lipid accumulation due to nitrogen starvation. Wild-type Chlamydomonas reinhardtii (CC-125) was cultivated in replete and nitrogen-limited conditions in order to achieve a range of lipid contents, as confirmed by Nile Red fluorescence measurements. A vector network analyzer was used to measure the dielectric scattering parameters of a coaxial region of concentrated cell suspension. The critical frequency f(c) of the normalized transmission coefficient vertical bar S*(21)vertical bar decreased with increasing lipid content but did not change with cell concentration. These observations were consistent with a decrease in cytoplasmic conductivity due to lipid accumulation in the preliminary transmission line model. This dielectric sensitivity to lipid content will facilitate the development of a rapid, noninvasive method for algal lipid measurement that could be implemented in industrial settings without the need for specialized staff and analytical facilities. (c) 2013 Elsevier Ltd. All rights reserved.