Separation of components of the biomass from high rate algal ponds using Percoll^R density gradient centrifugation

The biomass of a High Rate Algal Pond was separated into individual components of algae, bacteria and detritus. The two stage technique involved mechanical and chemical disaggregation of concentrated pond samples, followed by separation on preformed Percoll^R/sucrose density gradients. Throughout a diurnal cycle, monitored in September 1990, between 85 and 90% of the total chlorophyll a was recovered in the algal fraction. The greatest loss of chlorophyll from the sample occurred during the concentration stage; no further losses were encountered during physical and chemical disaggregation. The technique enabled the direct gravimetric determination of the separated algal biomass. The potential applications of the technique are discussed.