Hungry for algae 2 (nanocellulose)
In the first part of our hungry for algae series, we wrote about the application potential of algae as ingredients in food products. The next parts of this series will go way beyond that and will describe the usage potential of algae for biomaterials, biofuels, animal feed, fertiliser and wastewater treatment. A lot to write about, so let's start with the first one.
Algae as a source for biomaterial
Since some decades researchers are trying to optimise the process to produce the wonder material nano-cellulose from wood fibers. It can be lightweight, flexible, stronger than steel, stiffer than Kevlar and can even be conductive by mixing nano sized conductive material between the nanofibers. That’s what it’s a material many industries are craving for, but the process still consumes a lot of energy, which still prohibits the greater use of this unique polymer on a broad scale. Currently, it is made by adding water to cellulose-containing materials (usually wood waste, as would be found at a paper or lumber mills), then using high-pressure homogenisers, grinders or microfluidizers to rip the wood fibers into much smaller cellulose nanofibers. This results in a gel which is subsequently freeze-dried to remove the water, leaving the long, interconnected nanofibers behind.
Not so long ago, Researchers from the University Austin Texas now found a way to simplify this energy-intensive process by a lot using algae. At first, they started in the 1970th with the bacterium Acetobacter xylinum, which can secrete nano-cellulose fibers into a surrounding media, but with the improvement in genetics they swapped to the more efficient blue-green algae by implementing the nano-cellulose producing gene into the genome of the algae and which is way easier to cultivate and does even produce oxygen during the syntheses instead of CO2. This was in 2013 and bigger trials are still ongoing, but things look pretty promising that algae will become one of the main sources for more sustainable nano-cellulose.
The application possibilities of that new and hopefully soon cheap material are endless, starting from plastic-free packaging material for food products, to thin electronic conductors for more sustainable batteries, till even medicinal applications.
R.Malcolm Brown, for example, who was also the leading researcher at the Texan university and the implementation of the bacteria genome into the algae for the improved nano-cellulose production, filed a patent in 2015 for nano-cellulose based nonallergenic tissue transplants, based on the nano-cellulose produces by algae. Nano-cellulose is perfect for that as they can be made very flexible and thin films and can also be coated with antiseptic substances like lanosol, which can also be extracted from algae. It is a red algae variety is called Osmundaria serrata and showed to kill for example 99,99% of Staphylococcus aureus bacteria in tests, which is one of the most dangerous bacteria in a hospital, but also other bacteria and even fungi. It could also be a good alternative to usual Silver and Zinc oxides, which is often used in deodorant sprays and would be less toxic to the environment and would also be able to prevent the smell produced from the bacteria on our skin. So just another thing algae could be beneficial for.
Back to the materials itself, algae cannot just be used for the production of dense nano-cellulose materials, but also for soft foam materials. The US Startup Bloomfoam, for example, uses the algae foams floating on eutrophic lakes for the production of foamy materials for shoes, flip-flops, and mattresses by filtering the algae out of the water, which also helps the lake ecosystem to recover from this high nutrient load. A win-win situation for the business and the ecosystem.
You see algae can be a great source of biomaterials and this is just a glimpse into what it is out there. If you want to learn about this topic area don't hesitate to get in touch with us.
Looking forward to the next episode of hungry for algae