Paper Published: Price, Shieh, Sales 2015.

We have published a paper in The Journal of Visualized Experiments (JoVE) describing a novel reactor design called a high density bioreactor (HDBR) and it’s use for the cultivation of highly dense algal-bacterial communities. JoVE’s unique format combines traditional primary research manuscripts with video presentations to enhance the dissemination and adoption of new methods and technologies.





A novel reactor design, coined a high density bioreactor (HDBR), is presented for the cultivation and study of high density microbial communities. Past studies have evaluated the performance of the reactor for the removal of COD1 and nitrogen species2-4 by heterotrophic and chemoautotrophic bacteria, respectively. The HDBR design eliminates the requirement for external flocculation/sedimentation processes while still yielding effluent containing low suspended solids. In this study, the HDBR is applied as a photobioreactor (PBR) in order to characterize the nitrogen removal characteristics of an algae-based photosynthetic microbial community. As previously reported for this HDBR design, a stable biomass zone was established with a clear delineation between the biologically active portion of the reactor and the recycling reactor fluid, which resulted in a low suspended solid effluent. The algal community in the HDBR was observed to remove 18.4% of total nitrogen species in the influent. Varying NH4+ and NO3- concentrations in the feed did not have an effect on NH4+ removal (n=44, p=0.993 and n=44, p=0.610 respectively) while NH4+ feed concentration was found to be negatively related with NO3- removal (n=44, p=0.000) and NO3- feed concentration was found to be positively correlated with NO3- removal (n=44, p=0.000). Consistent removal of NH4+, combined with the accumulation of oxidized nitrogen species at high NH4+ fluxes indicates the presence of ammonia- and nitrite-oxidizing bacteria within the microbial community.


The paper can be accessed and downloaded here or from the publications page. The full journal article and video can also be accessed from JoVE’s website.

Read and listen to Algae could be an unlikely helper for cleaning wastewater, a segment on the radio program The Pulse.

View Cleaning Wastewater with Pond Scum in the Science and Technology Section of Drexel Now.

View Pond scum research is clearing the waters in The Triangle.

View Researchers turn to algae for waste treatment in Water Online.

Full Citation:

Price, J.R., Shieh, W.K., Sales, C.M. 2015. A novel bioreactor for high density cultivation of diverse microbial communities. J. Vis. Exp. (106), e53443, doi:10.3791/53443.