Light absorption and scattering by cell suspensions of some cyanobacteria and microalgae

Absorption spectra of cyanobacteria (Anacystis nidulans, Anabaena variabilis, and Chlorogloeopsis fritschii), red (Cyanidium caldarum and Porphyridium cruentum), green (Dunaliella maritima and Dunaliella salina) and diatom (Thalassiosira weisflogii) alga cell suspensions are presented; the spectra were obtained by using an approach developed earlier to compensate for scattering [1, 2]. In all species, the shapes of the absorption spectra were independent of the cell concentration. For Th. weisflogii and D. maritima, the analysis of selective and nonselective scattering was carried out. The effect of mechanical cell disruption on optical properties (absorption, scattering, and package effect) on D. maritima was studied. The character and dynamics of optical changes in D. salina under the influence of sodium chloride were followed.