In the quest for sustainable and cost-effective microalgae production, researchers have turned to an unlikely ally: herbicides. A recent study published in *Scientific Reports* (known in English as “Scientific Reports”) explores how natural isolates of the green alga *Chlamydomonas reinhardtii* can thrive in the presence of norflurazon, a common herbicide. This research, led by Kantinan Leetanasaksakul from the National Center for Genetic Engineering and Biotechnology at the National Science and Technology Development Agency, could have significant implications for the energy sector and the broader push towards a circular economy.
Norflurazon is widely used in agriculture to manage weeds by inhibiting carotenoid synthesis, which ultimately disrupts the photosynthetic machinery and causes cell bleaching. However, microalgae, which are increasingly seen as a valuable resource for biofuels and other high-value products, face challenges in mass cultivation due to contamination from other algae. This contamination can be devastating, leading to the collapse of entire cultures. The ability to cultivate microalgae that are resistant to specific chemicals could be a game-changer, reducing contamination and lowering production costs.
“Many norflurazon-resistant microalgae strains have been developed, but the use of genetically engineered organisms requires caution,” Leetanasaksakul explained. “We wanted to explore the potential of natural isolates that could tolerate norflurazon without genetic modification.”
The study evaluated 20 isolates of *Chlamydomonas reinhardtii* for their tolerance to norflurazon. Two isolates stood out, capable of withstanding concentrations of 5–10 µM, levels previously used to select mutant and transgenic strains. Physiological and proteomic analyses revealed that one isolate enhanced photosynthesis and photoprotection processes as its primary mechanism for tolerance. The other isolate, however, showed a reduction in protein synthesis, photosynthesis, and cell motility.
These findings suggest that natural isolates could be harnessed for large-scale microalgae production in the presence of norflurazon, offering a more sustainable and potentially cost-effective approach. The integration of microalgal production with phycoremediation—using algae to remove pollutants—could further contribute to a circular economy, where waste is minimized, and resources are efficiently recycled.
The research also raises important questions about the environmental impact of introducing chemically resistant strains into natural ecosystems. While the study focused on natural isolates, the broader implications for genetic engineering and conventional breeding methods remain a topic of ongoing debate.
As the energy sector continues to explore sustainable alternatives, the insights from this study could shape future developments in microalgae cultivation. By leveraging natural resistance mechanisms, researchers may be able to develop more robust and efficient production systems, ultimately contributing to a greener and more sustainable future.
“This research opens up new avenues for exploring natural resistance mechanisms in microalgae,” Leetanasaksakul added. “It’s a step towards more sustainable and cost-effective production methods that could benefit the energy sector and beyond.”