Streptophyte green algae are the closest known living relatives of land plants. Today, they are found in various environments and climate conditions, showing an impressive ability to adapt outside their native environment – water. One of the reasons behind this transition from water to land are UV- protective compounds – which, scientists say, could become a key sunscreen ingredient someday.
Since this type of algae can be found in multiple regions across the globe, researchers are interested in comparing samples from different locations to one another. Unsurprisingly, this kind of research can reveal that seemingly subtle variations are not so small when you put them under a microscope.
Building on the discovery of new strains of Streptofilum, Karin Glaser (Technical University Bergakademie Freiberg, Germany), Tatiana Mikhailyuk (National Academy of Sciences of Ukraine), Charlotte Permann (University of Innsbruck, Austria), Andreas Holzinger (University of Rostock, Germany), and Ulf Karsten (University of Rostock, Germany) focused on identifying their properties and differences from other strains of the same family of algae.
In preparation for this study, two new strains of Streptofilum were isolated from soil in different regions: one from coastal sand dunes in Germany and the other from tundra soil in the Arctic. By exposing them to desiccation (drying out), high and low light conditions, and UV radiation, the team of researchers observed how these algae survive – and thrive – on land.
The Arctic strain didn’t grow under UV exposure, but the other strain did, suggesting it can produce UV-protective compounds. With further research to confirm this ability and learn more about these compounds, the second type of algae could potentially be used for sun protection on human skin. Given that most of the sunscreens on the market today are based on chemical SPF, this is a promising discovery for our planet.
The study also found enough differences in the Arctic strain from other samples to classify it as a new species, Streptofilum arcticum. With cells covered by pili-shaped scales, this strain is different from other algae. Streptofilum arcticum is also very resilient: it can survive desiccation (drying out) and tolerate both high and low light conditions. This discovery suggests that Streptofilum algae could be more varied – and more widely distributed across the world – than previously thought.
