In dietary supplements, cosmetics, pharmaceutical products, and even in energy generation: microalgae are already used in a variety of ways. However, researchers are constantly discovering new application options for these little miracle plants.
The founders of the Portuguese company Algicel discovered a high concentration of the antioxidant astaxanthin in the microalgae in their native Azores, more precisely on the island of São Miguel. Antioxidants protect not only the skin’s cell structure, but also the whole body against oxidative stress and aging symptoms as well as inflammation.
Since 2007, the company has been researching a way to produce the health-promoting substance astaxanthin from the microalgae growing in their natural environment on the Azores. After all, the climate and pure inland waters of the islands are ideal for this type of microalgae. In the summer of 2019, the company started the industrial cultivation of the Haematococcus pluvialis species of microalgae based on the technology that was developed in-house.
In order to produce the microalgae for the mass market, the company first had to create an environment which is similar to that of the inland water bodies of the Azores. Algicel opted for so-called photobioreactors made of ACRYLITE® tubes.
The extruded acrylic tubes are UV permeable across the entire spectrum of sun rays and provides 92% light transmission, offering optimum conditions for the microalgae. Along with nutrients, water, and carbon dioxide from the air, algae primarily require plenty of even light to grow, making the ACRYLITE® acrylic tubes the obvious choice to cultivate the microalgae.
"ACRYLITE® acrylic is one of the most transparent materials available today. There is virtually no absorption of visible light in the material," says Janina Rossmann, Product Manager at Roehm. And, the transparency of the tubes remains unchanged for decades: ACRYLITE® has UV protection inherent to the material. This prevents yellowing and thus the loss of transparency. ACRYLITE® colorless tubes are backed by a 10-year warranty.
Thanks to these properties, the microalgae now grow under nearly natural conditions and reach their maximum number within just 30 days. Harvesting takes place by centrifugation of the mix – water/microalgae. "The absolute roundness of our tubes means that there are no edges that could cause trouble," Rossmann explains.
Then, the harvest cycle begins again. The more than 1,000 six-foot high tubes have to be rinsed and refilled with every cycle. The smooth, non-porous inner walls ensure that no putrid bacteria or microorganisms remain stuck to the walls. This keeps the ACRYLITE® tubes clean during the entire cultivation – thereby contributing to an efficient and sustainable biomass production.
