Cyanophycin from Urine


Cyanophycin from Urine

Urine accounts for only 1% of total household wastewater volume but is very rich in nutrients, in particular nitrogen and phosphorus. Recently it was shown that urine makes an excellent media for microalgae cultivation. However, the phosphorus to nitrogen ratio in urine does not match the requirement of microalgae, and part of the nitrogen is not removed. Cyanobacteria could make a promising alternative to microalgae for the treatment of urine since many species can accumulate the nitrogen-rich polypeptide cyanophycin. Cyanophycin derived bulk chemicals have applications for example in the nylon, acrylonitril industry and in the pharmaceutical industry


The biological characteristics of cyanophycin accumulation (kinetics and maximal yields) are still not well understood. No knowledge is available for cyanophycin accumulation under real outdoor production conditions for phototrophic cultures because all studies until now have been carried out at rather low light intensity of not more than 20% of maximal sunlight levels. Based on dedicated studies the real potential of this process thus needs to be assessed in the laboratory and, if successful, a real process needs to be developed for the concomitant treatment of urine and the production of cyanophycin-rich biomass.
In this project we aim to demonstrate and develop a process in which urine is treated and, at the same time, cyanophycin is produced with phototrophic cyanobacteria.


The plan is to make use of the high nitrogen to phosphorus ratio in urine to induce cyanophycin accumulation and improve nitrogen removal efficiency from urine. Cyanobacteria will be selected which are able to grow on minimally diluted urine and able to accumulate cyanophycin to large quantities for extended periods of time under non-sterile conditions. Cyanobacteria growth conditions on light and urine will be studied in order to steer and maximize cyanophycin production. After harvesting, cyanophycin will be extracted from the biomass.

Thesis Projects

Within this project there are various possibilities for doing a BSc or MSc thesis. If you are interested in doing a BSc or MSc thesis, feel free to contact me. Researcher: Vinu Ayyappan Nair