Eating algae as part of a balanced diet

Algae might be the nemesis of pond owners everywhere - but researchers at the University of Cambridge think it could help people who are seeking to increase the amount of vitamin B12 in their diet. B12 - for the uninitiated - is a key nutrient involved in blood and nerve cells. However, people with plant-based diets may not get enough of it, and algae might be able to help them. Professor Alison Smith is the head of the plant metabolism group at the University of Cambridge.

Alison - Algae are very simple plants. Most of them live in water and they take up vitamin B12 from the liquid that they live in. So bacteria that are also living in the same place, like in a pond, a river, or even the sea, the bacteria make the B12 and then algae take it up.

Chris - And the algae conveniently package it for us. And if we eat the algae, we get the B12.

Alison - Exactly. Whereas plants don't do that.

Chris - And that's why the emphasis in your world is on algae as being a possible way to remediate this problem with a plant-based diet.

Alison - That's right. Yes.

Chris - So tell us about how this might work then. What would be the idea here?

Alison - What we've been doing in my research is to investigate the interactions between algae and bacteria and trying to understand the processes by which the B12, which is a large molecule, can be taken up by these simple plants, they're unicellular plants and also which types of bacteria are best for the algae to live with. There are various types of B12 and the type that we need, called cobalamin, is also preferred by algae. So that's an important nuance. So it makes the B12 that you find in the algae, the same as the ones that humans want. But there are some bacteria that make different types of B12. There are lots of different ones and there's one in particular called pseudo cobalamin. And this is made by certain bacteria and algae can't really take that up and neither can humans. So knowing which types of bacteria to grow your algae with is obviously important if you're trying to make a food which is rich in B12 that humans can use.

Chris - So your argument would be, now you've identified who the algae need to have as a good bacterial bedfellow to get the B12 that they need. And what would we do? Would we grow lots of algae? A bit like we make Marmite from growing fungi or yeasts and we concentrate it to make a delicious snack. We would make algae based snacks.

Alison - It depends on your point of view.

Chris - <laugh>. Oh, you either love it or you hate it. Alison. It's said it divides people, doesn't it? Marmite. But would that be the idea then you do the same thing for algae and that's how we would get the B12 in our diet. But a vegan, for instance, would be very comfortable eating that because it's a plant.

Alison - That's right. Yes, you can make B12 from bacteria and that's how it's made when you prepare pills from it. But if you want to have a sort of natural diet, you can grow algae with benign bacteria, their own microbiome, and they will then take up the B12. Interestingly, yeast also doesn't make B12 and Marmite, which comes from the yeast, actually have B12 added to it.

Chris - Oh, so you could have a match made in heaven here <laugh>.

Alison - Horrible, horrible Marmite

Chris - <laugh>. Watch it. You don't, you don't want to have Marmite on the phone to you <laugh>. But could you add the algae to the Marmite perhaps? Is there a collaboration here? <laugh>?

Alison - I guess you could do that as well, <laugh>. But you know, I'd like to stick to it being green. How about that?