A collaboration between research teams from the Sandia National Laboratories (SNL) and Lawrence Livermore National Laboratories (LLNL) has developed a method to prevent algae feedstock crop collapse, the Bioenergy Technologies Office (BETO) of the US Department of Energy (DOE) announced.

Algae’s fast growth rate, dense culture and genetic diversity made it suitable for multiple applications, BETO said, and the SNL and LLNL team was exploring one application that has the potential to turn algae into sustainable aviation fuel (SAF).

However, despite algae’s versatility, algae ponds have the potential to “crash” or be overtaken by pests, BETO said, and this rapid deterioration posed significant challenges for the scaling up of algae production.

The researchers at SNL and LLNL were developing methods to monitor and predict pond crashes before they happened, giving pond operators time to implement countermeasures, the 29 March report said.

SNL scientist Todd Lane led the collaborative project to monitor chemical signals – called volatile organic compounds (VOCs) – emitted by algae when under stress, BETO said.

In a recent study in the journal Metabolites, the team described how they tested if the monitoring tool could distinguish between different types of algae stresses.

Biotic stress occurs due to damage done by an organism while abiotic stress is caused by non-living impacts on a specific environment.

In the study, funded through DOE’s Genomic Science programme within the Office of Biological and Environmental Research, the team used the algae strain Microchloropsis gaditana and subjected it to either grazing by a rotifer (a tiny animal predator that eats algae) or a series of freeze/thaw cycles. By using this method, they could compare biotic and abiotic stresses.

The study showed that algae being eaten by grazers put out different chemical signals compared to algae that were frozen and thawed, the report said. However, there were some common chemical signals, suggesting that algae produced general stress signals alongside signals specific to a particular stressor.

The group identified and reported on the specific VOCs emitted by the algae, BETO said, and these compounds could be used as chemical signatures to detect and diagnose early signs of stress in algal cultures with the aim of delivering targeted and effective treatments prior to a catastrophic culture crash.

“The efforts of our work to develop early diagnostic markers of a pond crash, specifically VOC biomarkers from abiotic- and biotic-wounded algae, has great potential to increase the yield of algae-derived compounds, with the target of reducing prices of manufacturing biofuel and bioproduct production precursors,” Kirsten Reese, the paper’s co-first author alongside Carolyn Fisher, said.

In addition to the team’s work on algae monitoring, it was also working on techniques to prevent algae crops being eaten, the report said.

Rotifers and fungi are common grazers and parasites that can lead to rapid algal pond crashes, according to the report, and the team identified a bacterial community that can be grown alongside an algal species, Microchloropsis salina, that protects it from grazing by the rotifer Brachionus plicatilis.