New PROMICON paper: Researching alternative measurements in cyanobacteria PHB production

A PROMICON-supported research article titled ‘Monitoring PHB production in Synechocystis sp. with hyperspectral images’ has been recently published in the Water & Science Technology Journal. The study investigates the application of hyperspectral technologies to monitor cyanobacteria population growth and PHB production. The research has been conducted by a team of leading experts, amongst whom are PROMICON project partners Francisco Rodríguez Lorenzo, Miguel Placer Lorenzo, Luz Herrero Castilla, Santiago Gómez, Juan Manuel Fernández Montenegro, Dr. Rubén Diez-Montero from AIMEN Technology Center and Polytechnic University of Catalonia · BarcelonaTech Dr. Joan Garcia and Eva Gonzalez-Flofrom the Polytechnic University of Catalonia · BarcelonaTech . 

Microalgae wastewater treatment systems have the potential for producing added-value products. In particular, polyhydroxybutyrates (PHBs) may be isolated from cyanobacteria and employed in the manufacturing of bioplastics. However, PHB production calls for appropriate culture conditions and ongoing monitoring, which puts a strain on cutting-edge technology.  

This study looks into the use of hyperspectral technologies to track the development of the cyanobacterial population and the generation of PHB. Therein, throughout the paper, the researchers have described the process of developing a revolutionary measuring technique that can identify spectral reflectance variations caused by light emitted to cyanobacteria in various stages, allowing for the separation of the PHB accumulation phase and the cyanobacterial growth phase.

The main conclusion reached in this paper are the following:

• The population of cyanobacteria may be monitored using hyperspectral technology.

• Spectral measurements vary between the growth and PHB-accumulation stages.

• Using machine learning techniques to define methodologies makes the categorization of pilot-scale microorganisms and stages possible.

• Algorithms for image recognition enable the visual evaluation of chlorosis progression.

The results of the analysis in this study present an interesting alternative for traditional measurements in cyanobacteria PHB production and its application in pilot-scale PBRs. Although not directly determining the amount of PHB production, they would give insights into the undergoing processes.

You can read the full paper here.

Photo: (a) Scheme of the tubular horizontal semi-closed PBRs’ configuration and (b) Agròpolis experimental campus of the Universitat Politècnica de Catalunya-BarcelonaTech (UPC) installations. Red arrows indicate the water flow direction. Green arrows indicate the flux direction inside each PBR. Blue arrows indicate the injection of CO2.