This episode is sponsored by Wren, a  website with a monthly subscription that helps fund projects to  combat the climate crisis.

Click the link in the description  to learn more about how you can make a monthly contribution to support projects  like rainforest protection programs. [♪ INTRO] Imagine a world run by aquatic plants,  maybe even the tiniest ones in pond scum. Yes, pond scum.

You know, that green  film that forms on top of the water? The film has tiny critters called  phytoplankton, one of many kinds of algae that exist on our planet. And they are an extremely important food  source for a lot of life on this planet, whether they are tiny, single-celled  plants or meters long like kelp.

They’ve also served as food for thought  for some scientists, inspiring them to use algae to improve upon  many of our everyday products. From sunscreen to oil, let’s take a look  at five products that are in development that use algae as a muse. Humans aren’t the only ones that  need to use sunscreen as protection from the Sun’s rays.

Even those that rely on the Sun for their food  need to protect themselves from it sometimes. Algae spend a lot of their time soaking  up ultraviolet rays, because the Sun is what helps drive photosynthesis. Without it, these tiny plants  wouldn’t be able to create their food.

But too much of something isn’t  great either; like with us humans, soaking up a lot of sunlight can damage  the DNA of these microscopic plants. So algae produce their own sunscreen,  as a way of keeping themselves safe from being damaged by too much Sun exposure. And researchers are drawing inspiration  from the chemicals that algae produce to shield themselves, in order to make  a better, less damaging alternative to oxybenzone, a common active  ingredient found in sunscreen.

Oxybenzone works really well as a Sun protectant, but it can be bad news for the environment. In ocean ecosystems, it’s been shown  to cause stress to corals, making them more susceptible to bleaching and  causing irreparable damage to their DNA. But algae can provide an alternative.

They produce all sorts of chemicals,  like some amino acids and carotenoids, that researchers are currently experimenting with  to produce a safer alternative to oxybenzones. Not only that, but they are also  pretty good at absorbing UV rays, and some may even prevent DNA  damage, instead of causing it. But there are still some hoops to  jump through before sunscreens made with compounds derived from algae  make it on the commercial market.

Like, there aren’t a lot of these  chemicals present in a single plant, so harvesting them requires a lot of algae. Not only does this make it  expensive, but it could also negatively impact algal populations. Researchers are aware that the harvest  has to be done in a sustainable way, where the benefits outweigh the costs.

Or maybe it’s just the case that they  need to isolate which chemical is best and attempt to make it synthetically. Still, algae-inspired sunscreens have a  lot of promise, and it wouldn’t be too surprising to see them adorning  shelves in the next few years, once all the kinks have been worked out. Not only do algae produce their own  sunscreens, but they also work to keep themselves from being infected by the  billions of bacteria that live in the ocean.

Some algal species have the super-cool  ability to produce a chemical that keeps the bacteria from forming a biofilm,  a thin layer of interconnected cells, on the algae. Researchers have found that the  red algae known as Delisea pulchra doesn’t have biofilms coating its  surface like other algae species. That’s because it produces a substance  that disrupts individual bacterial cells’ ability to talk to each other.

And if they can’t communicate with  each other, they can’t coordinate and form a biofilm on the algae. This particular chemical also keeps  bacteria from producing an enzyme that breaks down certain types of antibiotics. Now researchers are trying to  harness those same chemicals produced by the red algae to make self-cleaning  surfaces, or at the very least, surfaces that stay cleaner for  much longer than they currently do.

This coating could then be applied to any  surface, including clothing and money, which would work to stop the growth  of bacterial film in the same way that it works in the algae. And the company has already  reported that in trials, this chemical appears to work on  not only bacteria but also fungi. While we don’t have self-cleaning money  yet, it’s definitely in the works, thanks to the incredible  resiliency of an unassuming plant.

Another super useful thing that algae  produce are oils and fatty acids. These fats are produced by the algae  during the photosynthesis process, but accumulate in the individual  cells when the algae are stressed out, like when nutrients become scarce. They store these fats up, in order  to have an energy reserve to tap into until the stressful conditions pass.

And now algae are being tapped  commercially for their fatty acids, as a potential alternative  to palm oil and coconut oil. Palm oil is used in a lot of everyday  products, but it’s a particularly controversial source of oil. The harvesting process is driving  deforestation and causing the extinction of several species in the forest  where the oil gets harvested from.

So finding a non-controversial alternative is  necessary to protect these vital ecosystems. And that alternative might just be algae. For one, algae don't take up as  much space, and harvesting them for their fatty acids doesn't lead  to deforestation like palm oil.

Currently, the major hurdle is the expense. It's more expensive to process the  oils extracted from algae than palms, which is why palm oil is still  more enticing to producers, despite the havoc it wreaks on nature. But with more research  trials and better technology, researchers could make progress  in the right direction.

Another, less conventional use of those  oils produced by algae are lenses! Specifically, night-vision goggle lenses. Cameras that work in the dark have a lot  of uses, everything from the military to security systems to wildlife tracking cameras.

But current infrared night-vision  lenses are pretty expensive, and the images they produce  aren’t the best quality. And the main reason they’re expensive is  because when you switch to night vision you need to also change the focus of  the lens, kind of like changing lenses in a regular camera to focus on  something that’s far out or closed up. Plus they need to be able to hold  their shape as their focus is changed.

This ability is what makes them so expensive. But to make lenses with algal  oils you need a process known as inverse vulcanization, which is a  pretty cool process in and of itself. Normally polymers are made  from petroleum-based products.

But the inverse vulcanization process  avoids petroleum products altogether. It takes sulfur, an unwanted  byproduct of refining petroleum, and heats it up to make polymers. And because algal oils are made  up of long chains of carbon atoms, their length helps make the newly  formed polymer stable and stretchy.

Because night-vision cameras are  widely used in so many situations, there is a high demand for their lenses  to be made from commonly available, cheap materials that can provide  a better user experience. So using a more flexible product  can drop the cost of the lens, while still hanging on to its ability to focus. And harnessing products naturally  produced by algae may be just the trick to attaining lower-cost, flexible lenses.

So far, we’ve learned that algae have  a lot of tricks up their … cells? They can produce their own  sunscreen, antibiotics, and fats. Oh, and they can make their own food plus  at least half of the oxygen on this planet.

Now that’s some amazing skills  for anything, let alone a plant! When did you last make your own food  and the air that you need to breathe? But it doesn’t end there!

Researchers are looking to harness  the photosynthetic abilities of algae to create photosynthetic skin grafts. They’re combining algae with  fibrinogen, a collagen-like protein. This combination creates a material with  the photosynthetic qualities of algae and the strength of the protein.

And thanks to the plant part of the  material, this product not only uses photosynthesis to feed itself, it  produces oxygen in the process. Which is exactly why researchers  hope to be able to use this material for a skin graft. They see these types of grafts as a big  improvement over regular skin grafts, because they can produce oxygen.

This means that the photosynthetic  graft could be applied to tissues, even if there was a lack of  proper blood flow to that area. These types of grafts could also be  used to keep organs alive during organ transplant procedures, because they would  supply a source of oxygen to the organ while it was in transport and disconnected  from any sort of blood source. And researchers have already found  some success with a rudimentary version of this, at least in rats.

They stored the transplanted organs  in gas-permeable bags containing live algal cells, which increased the rats’  recovery and survival after surgery. And trials in mice have shown success with  their bodies' acceptance of the grafts. Not only did the mice immune  systems not reject the algal cells, but the part-plant and part-animal  tissues began to bond better, a process often referred to as a chimera.

Also, a very recent trial in humans  has found that these types of grafts have promise, in that the patient's  bodies didn't reject them, although that’s as far as researchers have taken it so far. There's a lot more work to be done to see  if these types of grafts are going to be more beneficial in the long run  over more traditional skin grafts, but they certainly do hold a lot of potential. There are already quite a few products  that involve algae already on the market.

Carrageenan, a red algae extract, is in  everything from ice cream to toothpaste. And there’s already been a flurry  of work around creating biofuels from the oils produced by algae. But I think that it’s safe to say these  algae-inspired products are taking things to the next level.

From sunscreen to photosynthetic  skin-grafts and everything in between, with a little more work and a lot of innovation, Beyonce’s song may soon need a new verse. Who runs the world? It’s  algae.

Algae runs the world. But something that shouldn’t run  the world is carbon emissions, and today’s sponsor Wren can help with just that. They are a website with a monthly  subscription that helps to fund projects to combat the climate crisis.

Wren searches around the globe for promising  projects, getting data on the ground to track their impact over time. Like protecting the Amazon using  high-tech video and satellite imagery to help communities on the ground  to detect deforestation early. Over the long term, we need  governments to fund these projects, but we can start by crowdfunding them.

And as a bonus, we’ve partnered with  Wren to protect an extra ten acres of rainforest for the first 100 people who  sign up using our link in the description! And as always, thanks for supporting SciShow. [♪ OUTRO]