James Wong: December 7th, 1941, a surprise Japanese aerial attack on the
James Wong: American Naval Base at Pearl Harbor in Hawaii initiated the
James Wong: formal entry of the United States into the second World
James Wong: War. Thousands were killed. The damage was extensive. In addition
James Wong: to those that died that day, the Pearl Harbor attack
James Wong: led to a far greater loss of life amongst the
James Wong: Allied forces. Since the start of the war, malaria had
James Wong: ravaged forces stationed in the West Indies. Only held at
James Wong: Bay by a wonder drug from the Dutch East Indies
James Wong: modern day, Indonesia. The source of this plantations of the
James Wong: humble Cinchona tree on the Island of Java, where 90% of
James Wong: the world's Quinine was sourced. Demand for this plant based
James Wong: malaria cure roared during wartime. But by crippling the Allied
James Wong: defense through the bombing of Pearl Harbor and the capturing
James Wong: of Singapore, there was nothing to stop the Japanese from
James Wong: taking Java and cutting off supplies to their enemies in
James Wong: the West In the effort to acquire the island's rich
James Wong: oil fields, Japan also denied its opponents one of the
James Wong: most crucial medicines in human history, and scientists were forced
James Wong: to seek out an alternative to the substance that had
James Wong: enabled Western colonization of the tropics for centuries.
Kim Walker: Cinchona has been called a tool of imperialism and that's
Kim Walker: because Quinine, which is the active antimalarial chemical found in
Kim Walker: the bark, was so important for empire, particularly across 18th and
Kim Walker: 19th century.
James Wong: Today, we find out how plants and medicines have changed
James Wong: the fortunes of nations, and their roots from forest to
James Wong: pharmacy throughout history. We'll hear how the hunger for cures
James Wong: has transformed landscapes, seen powers rise and fall, and altered
James Wong: human history forever.
Kim Walker: Quinine started to gain extra significance for them. So to
Kim Walker: be able to control the quality and quantity of supply
Kim Walker: became very important. Plantations started to be grown in British India and
Kim Walker: Dutch Indonesia.
James Wong: And we'll hear what we can learn and how lives
James Wong: can be saved in the search for modern day medicines.
Dr. Melanie-Jayne Howes: Plants are actually brilliant chemists.
James Wong: I'm James Wong, and welcome to Unearth Mysteries from an
James Wong: unseen world from Royal Botanic Gardens, Kew. Today, I'm finding
James Wong: out how one kind of tree changed the course of
James Wong: world history. The cinchona tree is native to South America.
James Wong: Myth has it that in 1630, the Spanish Countess of Chinchon
James Wong: visited Peru and fell ill with a fever. The substance
James Wong: given to cure her was the bark of cinchona, which we now
James Wong: know contains many useful substances, only one of which is
James Wong: Quinine. And whilst the real story of how cinchona's healing
James Wong: properties first made it into medicine, remains a mystery, there
James Wong: are plenty of clues to help us piece together some
James Wong: of that history. The Royal Botanic Gardens, Kew has one
James Wong: of the largest collections of cinchona bark in addition to
James Wong: Herbarium specimens and a wealth of historical records from the
James Wong: 19th century when Quinine was transported around the world. It's this
James Wong: archive that makes Kew, so compelling for my first guest.
Kim Walker: I'm Kim Walker, and I am a PhD student at
Kim Walker: Kew. And I work in the Economic Botany Department and
Kim Walker: I study that collection of cinchona bark. It does sound
Kim Walker: a bit dry, doesn't it studying bark? But actually if
Kim Walker: you're going to pick a bark, this is probably one
Kim Walker: of the most interesting ones in history. Cinchona bark contains
Kim Walker: Quinine which for over 300 years was the only known
Kim Walker: malaria treatment in Europe. And also is the flavoring in
Kim Walker: everybody's favorite cocktail, the gin and tonic, because it is
Kim Walker: the flavoring and tonic water.
James Wong: When we talk about malaria, it's quite difficult to picture a world
James Wong: before cinchona bark was in existence, because malaria wasn't something that was just found in
James Wong: remote location.
Kim Walker: Yeah, absolutely. So it's just slightly out of living memory
Kim Walker: now. So not many people realize that we used to have
Kim Walker: malaria and Britain all the way up to the first World War.
James Wong: So tell me about the history of cinchona bark. How
James Wong: do we know that it contains Quinine and that that's
James Wong: an effective treatment for malaria?
Kim Walker: That's a really interesting question because when the Spanish entered South
Kim Walker: America, which is where cinchona comes from originally, across the
Kim Walker: Eastern slopes of the Andes, before this period, malaria, or
Kim Walker: at least a very severe forms of malaria didn't exist.
Kim Walker: So as the Spanish come in, bringing malaria with them,
Kim Walker: and Cinchona trees already grow South America is not very
Kim Walker: clear who or when somebody connected that cinchona bark kills
Kim Walker: malaria. But it's likely that it would have been indigenous healers, had
Kim Walker: really superior knowledge of local botanics and healing. And so
Kim Walker: at the (inaudible) , as it were, where new diseases were
Kim Walker: entering the country and cinchona may have already been in
Kim Walker: use for other things, they would have put two and
Kim Walker: two together and found the treatment. We do know that
Kim Walker: was around about 1600. And by about the mid 1600s cinchona
Kim Walker: bark started being imported into Europe.
James Wong: Is this presumably because cinchona bark was really important for
James Wong: industry at one point in time? People wouldn't be able to
James Wong: conduct business across large parts of the world, if you
James Wong: couldn't physically access them while staying healthy.
Kim Walker: Absolutely. So cinchona has been called a tool of imperialism
Kim Walker: and that's because Quinine, which is the active antimalarial chemical found
Kim Walker: in the bark, was so important for empire, particularly across 18th and
Kim Walker: 19th century. And so, for many different countries within Europe
Kim Walker: who are interested in expanding into new territories and colonizing
Kim Walker: areas, such as India and parts of Africa, Quinine was
Kim Walker: really important because unless you can control disease, whenever you
Kim Walker: were to go somewhere that may have something like malaria,
Kim Walker: you're more likely to die off than to be able to
Kim Walker: enter those places.
James Wong: How is Quintin traditionally administered? Was it administered in tonic water?
Kim Walker: Tonic water came a little bit later in the 19th century,
Kim Walker: which is about the mid 1800s. But originally how Europeans
Kim Walker: started to use cinchona was in very traditional ways to
Kim Walker: use medicine, which is getting the bark, which is a
Kim Walker: very tough material, grinding up into a powder. So you
Kim Walker: can crack open all the plant cells and get the
Kim Walker: chemicals out, and then dilute it. And the best way
Kim Walker: to dilute and extract chemicals quite often is by using
Kim Walker: a bit of alcohol. So early ways to dilute it
Kim Walker: would have been using wine, or port, or perhaps stronger
Kim Walker: spirits like brandy. By the 19th century, it was one of
Kim Walker: the largest imports of American drugs imported to Europe. Demand
Kim Walker: started to outstrip supply, and it started to be over
Kim Walker: harvested in the world by some unscrupulous harvesters. And as this
Kim Walker: happened, and as the 19th century grew older and different
Kim Walker: empire started to look further afield to colonize new areas,
Kim Walker: Quinine started to gain extra significance for them. Around the
Kim Walker: early 1900s, different countries, particularly the Dutch and the British,
Kim Walker: started to look into how they could get hold of
Kim Walker: this tree for themselves to cultivate. Quinine was used all
Kim Walker: the way up to the second World War, when supplies
Kim Walker: from Indonesian plantations got caught off. Unfortunately, using Quinine to
Kim Walker: control the ability to colonize the areas is not a very
Kim Walker: nice thing to think about. And for the British and the
Kim Walker: Dutch to get hold of these trees, they were going
Kim Walker: to have to basically smuggle them out of South America.
Kim Walker: And they were justifying that as saving the seeds because
Kim Walker: of over harvesting, which is very complicated, because really nowadays
Kim Walker: you wouldn't do that. You would work with communities to
Kim Walker: bring up the cinchona bark and make it available for
Kim Walker: everybody if they chose to. Everything was different then. And
Kim Walker: unfortunately, they smuggled out to make plantations in India and Indonesia.
James Wong: So in that time, that was really considered par for the core.
James Wong: So people wouldn't have raised an eyebrow at all about
James Wong: the idea of taking plant material for one part of
James Wong: the world, or taking the knowledge of plant material even,
James Wong: and applying it for themselves. But nowadays we actually have
James Wong: a term for that bio- piracy and the same way
James Wong: that you would pirate a bootleg CD or a copy
James Wong: of a film that you download off the internet. We
James Wong: would have the same term for biological genetic information, and
James Wong: also information about how to grow and use plants. Now
James Wong: I should just point out here that Kim's book, Just
James Wong: the Tonic a Natural History of Tonic Water, which she co-
James Wong: wrote with Mark Nesbitt, is a fantastic read. If you'd
James Wong: like to delve a little deeper into the rich history of
James Wong: this favorite tipple, then check it out. The Cinchona story
James Wong: is just one example of how a naturally occurring medicine
James Wong: played an essential role in the movement of people internationally.
James Wong: With the current conversation about the British empire and its
James Wong: legacy, it's fascinating to me to contemplate whether European powers
James Wong: would have been able to colonize the world's tropical regions
James Wong: to the same extent, if at all, without this wonder
James Wong: drug. Or would history have unfolded quite differently? It's amazing
James Wong: to think that this humble tree might have carried the
James Wong: course of history upon its delicate branches. Nowadays, scientists are
James Wong: investigating new substances that can be created using other alkaloids
James Wong: within cinchona bark. And while science is opening more doors
James Wong: to plant medicines every day, they are still a constant
James Wong: source of novel, unexpected compounds. I chatted to Dr. Bente
James Wong: Klitgaar, Senior Research Leader in Identification and Naming and Head
James Wong: of the Americas Department at Kew. She's mostly based in
James Wong: the Herbarium where seven million plant specimens are held. Her
James Wong: team looks after the two million of them from the
James Wong: Americas. My first visit to Kew's Herbarium was 15 years ago
James Wong: now, and I was just starting on my master's. And
James Wong: it's quite difficult to picture what seven million samples is
James Wong: like. But to me, it was like going into a
James Wong: scene from Harry Potter, just floor after floor in this
James Wong: beautiful old Victorian building, of course, with some modern adjuncts
James Wong: now. And a Herbarium is to an untrained eye, just
James Wong: millions of pressed flower specimens.
Dr. Bente Klitgaar: They are.
James Wong: It's like some kind of someone's hobby just went really
James Wong: out of control. Why is it important to have so
James Wong: many just pieces of plant squished between paper?
Dr. Bente Klitgaar: They are the ultimate evidence. Because we don't just have
Dr. Bente Klitgaar: one of each plant species, we have about 80% of
Dr. Bente Klitgaar: the biodiversity in terms of the generic level, which is
Dr. Bente Klitgaar: a bit scientific, represented in Kew's Herbarium. So, Kew's Herbarium is one of
Dr. Bente Klitgaar: the best global collections in the world. And as I said, we can use it for any type
Dr. Bente Klitgaar: of research, because we don't have to have all one
Dr. Bente Klitgaar: of each species, we have the whole distribution range. I have
Dr. Bente Klitgaar: some plants that I have known ever since I started
Dr. Bente Klitgaar: my career in botany. And these are the legume family that I have been
Dr. Bente Klitgaar: specializing. I've been doing many things in my career, but
Dr. Bente Klitgaar: the legume family has always been part, been my friend all
Dr. Bente Klitgaar: the way along.
James Wong: So peas and beans, the legume family. It's such a massive
James Wong: family. And this includes everything from tiny little herbs in
James Wong: the Arctic Tundra-
Dr. Bente Klitgaar: Exactly, yes.
James Wong: ... right up to giant Amazonian trees.
Dr. Bente Klitgaar: Yes. Some of the biggest emergence in the Amazon are
Dr. Bente Klitgaar: legumes as well. So I'm going to show you some of
Dr. Bente Klitgaar: my very, very best friends and my first legume friend.
Dr. Bente Klitgaar: It's a genus called Brownea. When I started working on
Dr. Bente Klitgaar: this genus called Brownea, they're rainforest trees. They occur only
Dr. Bente Klitgaar: in Northwestern, South America. And I can show you-
James Wong: Wow, look at that.
Dr. Bente Klitgaar: Yeah. Yeah. So, at Key, we are very, very lucky.
Dr. Bente Klitgaar: There's one in the Palm house, which is Brownea Coccinia,
Dr. Bente Klitgaar: and there's one at Princess or Wales Conservatory called Brownea grandiceps.
Dr. Bente Klitgaar: So when I miss them, I can go into one
Dr. Bente Klitgaar: of these green houses, and they flower as well, they're fantastic. They get up about a football size.
James Wong: It looks like something straight out of the movie Avatar.
James Wong: It's like a giant pompom flower with these really, really
James Wong: long filaments that are coming out of it.
Dr. Bente Klitgaar: Yeah.
James Wong: Almost like you've got a big fistful of the showiest
James Wong: rhododendron and stuck them all together-
Dr. Bente Klitgaar: Exactly.
James Wong: ... and just made them look even more exotic.
Dr. Bente Klitgaar: As a young scientist, I decided to work on this
Dr. Bente Klitgaar: group for my Master's thesis. So I went then and my task was
Dr. Bente Klitgaar: to understand that the Brownea is species in Ecuador. That was one
Dr. Bente Klitgaar: task, and the other task was then to understand how the Brownea species
Dr. Bente Klitgaar: were used in Ecuador. And I wanted to write a book about
Dr. Bente Klitgaar: children who live in the rainforest. So I actually got
Dr. Bente Klitgaar: myself a deal with a publisher. And I went and visited
Dr. Bente Klitgaar: some indigenous communities in the Amazon at the same time.
Dr. Bente Klitgaar: So I realized-
James Wong: Talk about multitasking there. Is there anything you can't do?
Dr. Bente Klitgaar: I try and spoil it. But some indigenous tribes in
Dr. Bente Klitgaar: Northern Ecuador, they actually use one Brownea, a species of Brownea, grandiceps, as a contraceptive. And
Dr. Bente Klitgaar: I did lots of literature work. And I realized that
Dr. Bente Klitgaar: actually several species had been used by other indigenous tribes
Dr. Bente Klitgaar: in Colombia, in Venezuela, and in Ghana. So it's not,
Dr. Bente Klitgaar: it wasn't an isolated phenomenon. None of the families have
Dr. Bente Klitgaar: more than four children. The legume family members of the family, or members of the
Dr. Bente Klitgaar: legume family, it's been shown that they are the only
Dr. Bente Klitgaar: family to contain a group of chemicals called flavonoids, or
Dr. Bente Klitgaar: isoflavonoids. And these flavonoids or isoflavonoid, they've been found in a species of clover called trifolium
Dr. Bente Klitgaar: subterraneum. They have this estrogenic effect.
James Wong: Having clues like this from naturally occurring compounds can get
James Wong: scientists really excited, as it offers possible clues for building
James Wong: affordable, safe, and sustainable alternatives for human use in a
James Wong: lab. Bente explained why research like hers is so vital
James Wong: in the first place.
Dr. Bente Klitgaar: It has proved my viable. It has proved viable that you
Dr. Bente Klitgaar: found one compound in one plant that is protective against
Dr. Bente Klitgaar: cancer. And you can start to synthesize that part, but
Dr. Bente Klitgaar: you wouldn't have found that compound had you not found
Dr. Bente Klitgaar: it in a plant first.
James Wong: And that covers everything from some of the most important
James Wong: cancer drugs used in conventional medicine-
Dr. Bente Klitgaar: Yeah, yeah.
James Wong: ... to the leading treatment for malaria.
Dr. Bente Klitgaar: Exactly. Exactly.
James Wong: So want to know is, did you ever write the
James Wong: children's book?
Dr. Bente Klitgaar: Unfortunately, I got very sidetracked by the science.
James Wong: Thanks for listening to Unearthed. I'll be back again in
James Wong: just a minute. But first here's a message from our
James Wong: supporter, Kim Catrall.
Kim Catrall: As a charity, the Royal Botanic Gardens, Kew is facing
Kim Catrall: a severe funding crisis right now. The impact of Coronavirus
Kim Catrall: has created a financial shortfall of 15 million pounds. This
Kim Catrall: money is vital for the upkeep of these beautiful botanic
Kim Catrall: gardens and crucial to continuing its global conservation work. Plants
Kim Catrall: and fungi hold many of the answers to the world's
Kim Catrall: biggest challenges, such as climate change, food security, and biodiversity
Kim Catrall: loss. And Kew needs to play a role in furthering
Kim Catrall: the science and identifying desperately needed solutions. If there's one
Kim Catrall: positive thing that could come out of this pandemic, it
Kim Catrall: will be to encourage each and every one of us
Kim Catrall: to look afresh and with urgency at these global challenges.
Kim Catrall: If you are enjoying this podcast, and feel inspired by
Kim Catrall: the work that Kew does, please go to Kew. org
Kim Catrall: to donate today, to help not only protect Kew, but
Kim Catrall: also preserve the future of our planet.
James Wong: A really exciting area of Kew's modern day remit, lies
James Wong: in the evaluation of plants. And this can mean traveling
James Wong: far and wide to learn about new species, as well
James Wong: as how they're being used by local people.
Tom Prescott: I'm Tom Prescott, and my job title is Evaluation of
Tom Prescott: Plant Uses. I'm mainly focused on looking for potential medicines
Tom Prescott: from plants and fungi. So I first fell in love
Tom Prescott: with Papua New Guinea, kind of, I was working in
Tom Prescott: Australia and I decided to kind of go up there
Tom Prescott: and have a brief look. And then later on, when
Tom Prescott: I managed to start to get field work funding from
Tom Prescott: when I was an undergraduate, I started to go there.
Tom Prescott: People walk around barefoot and you have to. I'm quite
Tom Prescott: convinced of the idea actually, that if you live in
Tom Prescott: the rainforest permanently shoes are of very little value to you. And
Tom Prescott: the reason is that, just going about your day to
Tom Prescott: day business, walking across rainforest terrain, you need that sort
Tom Prescott: of tactile feedback from your feet. So for example, when
Tom Prescott: you're walking along, there's lots of deep ravines where the
Tom Prescott: little rivers at the bottom and you walk over essentially
Tom Prescott: tree trunks, from trees that have fallen over that act
Tom Prescott: like a bridge to walk across. But the downside is
Tom Prescott: if you get kind of scratched by something on your
Tom Prescott: ankle, in a rainforest environment, it gets infected really quickly.
James Wong: After experiencing an infection himself, Tom became deeply interested in
James Wong: how local plants were being used to treat them. Fortunately,
James Wong: the antibacterial, or antimicrobial properties of some plants are there
James Wong: to help tackle infections before they get serious.
Tom Prescott: My interest is the plant medicines that are used to
Tom Prescott: treat these cutaneous ulcers, so skin ulcers, which are really
Tom Prescott: common there. They're quite debilitating, and because they go deep
Tom Prescott: into the tissue, they're really, really painful. There's a kind
Tom Prescott: of more serious side to it, which is that they
Tom Prescott: act as a possible gateway for secondary infections. So there's
Tom Prescott: another kind of bacterial infection caused by Treponema bacteria. And
Tom Prescott: it's sort of believed or theorized to be the case
Tom Prescott: that once you have one of these little skin ulcers,
Tom Prescott: that all the kids have gotten these villages, the Treponema
Tom Prescott: bacteria can then get into your body. And Treponema causes
Tom Prescott: something called Yaws Disease. And that that can have really
Tom Prescott: horrific consequences. It's not uncommon for plants to produce anti-
Tom Prescott: microbial substances. And then people who live in rainforests have
Tom Prescott: adapted to their environment, by learning which plants to use,
Tom Prescott: to put onto these infected skin ulcers. Eighty percent of
Tom Prescott: people in Papua New Guinea live in rural areas, and
Tom Prescott: when we say rural, we don't really mean people driving
Tom Prescott: around in Land Rovers in Devon. We mean people living
Tom Prescott: right out in really hard to access areas. The one
Tom Prescott: thing that a plant medicine has that can really win
Tom Prescott: over a conventional pharmaceutical treatment. And the one thing that
Tom Prescott: has that will basically beat the other treatment hands down
Tom Prescott: every time, is it exists in the field, and it's
Tom Prescott: constantly there.
James Wong: Tom's fascination with local medicines available in the Papua New
James Wong: Guinea rainforest led him to run trials, comparing how these anti-
James Wong: microbial plant treatments with the sorts of things you can
James Wong: buy over the counter in the UK. We had a
James Wong: serious geek out about this. This is knowledge that people
James Wong: in societies all over the world have potentially had for
James Wong: decades, 100s, maybe even 1000s of years. But it's only
James Wong: being reported scientifically now. And skin ulcers are something that
James Wong: affects millions of people worldwide. So if there's an ability
James Wong: to find a treatment for them, that is somehow more
James Wong: effective, or either as effective as conventional therapies, then there's
James Wong: some real massive potential benefit to humanity here. What have
James Wong: we found so far?
Tom Prescott: The most promising plant that we've been looking at is something
Tom Prescott: called Ficus septica, which is a species of tropical fig.
Tom Prescott: And also a crucial point here is that we're looking
Tom Prescott: for the most common anti- microbial plant that we can
Tom Prescott: find. The rationale is that we want to find clinical
Tom Prescott: evidence to support the use of a traditional medicine, but
Tom Prescott: the traditional medicine should be so common that anybody in
Tom Prescott: any village, virtually in lowland Papua New Guinea, you could just walk
Tom Prescott: 50 yards and find this plant, and use it anytime
Tom Prescott: they want to. Ficus septica has really good antibacterial activity.
Tom Prescott: It produces lots and lots of little figs, sort of
Tom Prescott: like berry like things. And if you walk up to
Tom Prescott: Ficus septica, which is a small tree, and you can
Tom Prescott: find it kind of growing pretty much anywhere in lowland
Tom Prescott: Papua New Guinea, you pull off one of these little
Tom Prescott: fruit like things, and then this really beautiful white sap
Tom Prescott: starts dripping out of the end of the berry. And
Tom Prescott: the sap contains all these anti- microbial compounds. And what
Tom Prescott: you notice as it produces a slight sort of reddening around
Tom Prescott: where the sap has been, nothing too extreme, but as
Tom Prescott: if there's a little kind of immune response coming back,
Tom Prescott: which is quite interesting. But the other thing that the
Tom Prescott: plant sap does that we've seen really clearly is it
Tom Prescott: forms a kind of flexible plastic kind of covering over
Tom Prescott: the wound. There are flies that are attracted to these
Tom Prescott: wounds and they're believed to be transmitting bacteria. And I've
Tom Prescott: noticed this when I first had one of these infected
Tom Prescott: wounds, they make contact with the sap, it's almost like
Tom Prescott: they get a physical shock and they jump straight back,
Tom Prescott: and they won't go within a few millimeters of it.
James Wong: So you have the anti- microbial response, which gets rid
James Wong: of the infection, potentially it reduces your body's reaction to
James Wong: that, the inflammation, which can cause a lot of pain.
James Wong: It then seals the wound and also prevents secondary infection
James Wong: from insects. That's nuts, like four different things all in
James Wong: one plant.
Tom Prescott: Yeah. I was pretty surprised to see all of this.
Tom Prescott: I think there is a lot more out there in the rain
Tom Prescott: forest that's waiting to be discovered.
James Wong: It's so exciting to me to hear how the botanical
James Wong: world is still offering new scientific surprises, and helping us
James Wong: find solutions to old problems as we share knowledge around
James Wong: the world. It makes you wonder what other undocumented answers
James Wong: lie within the realms of our forests, hiding in plain
James Wong: sight. From rainforest now to a forest of information. In
James Wong: addition to Kew's living collections of medicinal plants, the economic
James Wong: botany collection, or ECB, holds around 25, 000 items of medicinal plant
James Wong: materials, including the Royal Pharmaceutical Society's collection of medicines, as
James Wong: well as Chinese traditional medicines. I found out how we're
James Wong: working with plants to make medicines today with Dr. Melanie-
James Wong: Jayne Howes.
Dr. Melanie-Jayne Howes: So my name is Melanie Howes. So I lead research
Dr. Melanie-Jayne Howes: in phytochemistry and pharmacognosy at Kew. So much of my
Dr. Melanie-Jayne Howes: research currently involves investigating the chemistry of plants, but especially
Dr. Melanie-Jayne Howes: to understand their uses as medicines and also for our
Dr. Melanie-Jayne Howes: health, such as in our diets.
James Wong: It's very easy to assume that the uses of plants in
James Wong: medicine is a historical anecdote. They were very interesting in
James Wong: the past, in the Roman empire, but in modern pharmacology,
James Wong: they're not used to the same extent. How accurate would
James Wong: you think that common belief would be?
Dr. Melanie-Jayne Howes: We have so many examples of pharmaceuticals, which were originally
Dr. Melanie-Jayne Howes: discovered from plants. So some of these are the original
Dr. Melanie-Jayne Howes: chemical that was derived from the plant itself. Some of
Dr. Melanie-Jayne Howes: them are derivatives. And some of them, we use the
Dr. Melanie-Jayne Howes: plant chemical to inspire us, to design a brand new
Dr. Melanie-Jayne Howes: medicine. And we have many of these examples available in
Dr. Melanie-Jayne Howes: clinical use currently. So for diseases such as dementia, cancer,
Dr. Melanie-Jayne Howes: heart disease, malaria, and diabetes, we have many pharmaceuticals that
Dr. Melanie-Jayne Howes: were originally inspired or provided by plants.
James Wong: So we're not talking about things that are limited to
James Wong: herbal medicines that you might buy in a alternative remedy
James Wong: shop. We're talking about things that you'd get in a
James Wong: regular pharmacy that would be prescribed on the NHS, for example.
Dr. Melanie-Jayne Howes: Precisely. I mean, up until around sort of the early 19th century,
Dr. Melanie-Jayne Howes: most people were using plants in the form of herbal
Dr. Melanie-Jayne Howes: medicines. So these contain mixtures of many different plant compounds.
Dr. Melanie-Jayne Howes: But then in the early 19th century, morphine was first
Dr. Melanie-Jayne Howes: isolated from the opium poppy. And this completely revolutionized how
Dr. Melanie-Jayne Howes: people used plants as medicine. Because for the first time,
Dr. Melanie-Jayne Howes: we were, or humans were, isolating single chemicals from plants
Dr. Melanie-Jayne Howes: and then developing these as a medicine. So this is
Dr. Melanie-Jayne Howes: really the concept of the single active ingredient or the
Dr. Melanie-Jayne Howes: pharmaceutical that we are familiar with in modern medicine today,
James Wong: Opium and its derivatives are still used in modern medicine.
Dr. Melanie-Jayne Howes: Absolutely. I mean, opium is a source of not only
Dr. Melanie-Jayne Howes: morphine, but another analgesic, which was also discovered in the
Dr. Melanie-Jayne Howes: 1800s, which is codeine. And both of these are currently
Dr. Melanie-Jayne Howes: in clinical use. And we still rely on the plant
Dr. Melanie-Jayne Howes: to obtain these alkaloids. Because as humans, we can't synthesize
Dr. Melanie-Jayne Howes: them easily from scratch in the laboratory. But morphine isn't
Dr. Melanie-Jayne Howes: just used itself as an analgesic. It's actually inspired the
Dr. Melanie-Jayne Howes: development of many other medicines. So this includes other analgesic
Dr. Melanie-Jayne Howes: medicines to help with pain, but also for other types
Dr. Melanie-Jayne Howes: of drugs, which are used for conditions such as coughs,
Dr. Melanie-Jayne Howes: addiction, and also Parkinson's disease. But opium also contains a
Dr. Melanie-Jayne Howes: completely different type of alkaloid chemical called Papaverine. Now this
Dr. Melanie-Jayne Howes: has very different properties. So one of its effects is
Dr. Melanie-Jayne Howes: that it can dilate blood vessels. So this compound was
Dr. Melanie-Jayne Howes: used to inspire the design of a drug called Verapamil,
Dr. Melanie-Jayne Howes: which is now in clinical use for certain heart conditions.
Dr. Melanie-Jayne Howes: So the opium poppy has been very important in discovering
Dr. Melanie-Jayne Howes: medicines, which we still find useful today. Plants are actually
Dr. Melanie-Jayne Howes: brilliant chemists. The story of aspirin is actually a very
Dr. Melanie-Jayne Howes: interesting story as a medicine, because it's discovery began in
Dr. Melanie-Jayne Howes: the mid 1700s when the bark of the willow tree
Dr. Melanie-Jayne Howes: was tested in people, and it seemed to be useful
Dr. Melanie-Jayne Howes: to reduce fevers. But it wasn't until the next century
Dr. Melanie-Jayne Howes: that it was discovered that the willow bark contains a
Dr. Melanie-Jayne Howes: certain type of chemicals called salicylates. And these were found
Dr. Melanie-Jayne Howes: to be the active ingredients of the willow bark. And
Dr. Melanie-Jayne Howes: they were the inspiration for the developments of the drug
Dr. Melanie-Jayne Howes: aspirin. But then it wasn't for another 80 years or
Dr. Melanie-Jayne Howes: more, that scientists actually uncovered its mode of action. So
Dr. Melanie-Jayne Howes: aspirin in the 1970s was found to inhibit the synthesis
Dr. Melanie-Jayne Howes: of some inflammatory substances in the body called prostaglandins. But
Dr. Melanie-Jayne Howes: its story doesn't end there. So even much later still,
Dr. Melanie-Jayne Howes: aspirin was found to have another completely new role in
Dr. Melanie-Jayne Howes: medicine. It was found to inhibit the aggregation of platelets
Dr. Melanie-Jayne Howes: in the blood. So as a result, aspirin became used
Dr. Melanie-Jayne Howes: more widely as a medicine to help reduce the risk
Dr. Melanie-Jayne Howes: of blood clots in people that could be at risk
Dr. Melanie-Jayne Howes: of certain heart conditions. So from the 1700s to the 1990s, we've
Dr. Melanie-Jayne Howes: still been making discoveries about a widely used drug, originally
Dr. Melanie-Jayne Howes: inspired by a plant.
James Wong: So it isn't just about harnessing a chemical that instantly has
James Wong: a therapeutic effect. It can be sometimes just using it as a
James Wong: roadmap for inspiration. But the compounds found in plants can
James Wong: be useful as an ingredient in which to create drugs after.
Dr. Melanie-Jayne Howes: Absolutely. Yeah. Much of the research we've been doing in
Dr. Melanie-Jayne Howes: recent years is looking at members of the mint family,
Dr. Melanie-Jayne Howes: so the lamiaceae. So these are common herbs, which are
Dr. Melanie-Jayne Howes: often used as part of our diet for flavoring food,
Dr. Melanie-Jayne Howes: such as sage, rosemary, lemon balm, and mint. And we've
Dr. Melanie-Jayne Howes: found some very interesting properties associated with these. We're really
Dr. Melanie-Jayne Howes: scrutinizing their chemistry to find out which specific chemicals occur
Dr. Melanie-Jayne Howes: in them and how they might have potential effects that
Dr. Melanie-Jayne Howes: could be useful to our health. Particularly, if used as
Dr. Melanie-Jayne Howes: part of our diet.
James Wong: It's thought that up to 50% of medicinal plant species
James Wong: will be extinct by the end of the century.
Dr. Melanie-Jayne Howes: So it's absolutely critical that we can protect biodiversity. There
Dr. Melanie-Jayne Howes: is now a shift to looking at plants, to use
Dr. Melanie-Jayne Howes: them to inspire us, to discover new medicines rather than
Dr. Melanie-Jayne Howes: exploit them.
James Wong: It's so easy to dismiss plant- based medicines as merely
James Wong: interesting historical anecdotes, a relic from another time. Yet 80%
James Wong: of the human population still relies on compounds found in
James Wong: plants as their primary form of healthcare. With at least
James Wong: half of all of the most commonly prescribed pharmaceuticals being
James Wong: originally derived from natural sources, unbeknownst to us, this includes
James Wong: a large chunk of the stuff in our own medicine
James Wong: cabinets. From local indigenous populations to international world- shaping cures,
James Wong: plants have been essential to human health since the dawn
James Wong: of humanity. And the reality is even today, we're still
James Wong: just beginning to scratch the surface of their potential. Thanks
James Wong: to breakthroughs in modern technology, we're able to travel further
James Wong: and learn more about how we can demystify these properties
James Wong: to make better lives for all. And none of this
James Wong: would have been possible without working alongside the people who
James Wong: live near and use those plants, being so generous with
James Wong: their knowledge. These communities and the information they share, can
James Wong: be absolutely vital to scientific discovery. Understanding the potential applications
James Wong: of plants from people who've been using them for 100s,
James Wong: if not 1000s of years has repeatedly proven to lead
James Wong: to game changing medical discoveries. And there is so much
James Wong: more to learn. To me, it's quite incredible to think
James Wong: how much of our learning in this area has taken
James Wong: place in the last few hundred years, a blink in
James Wong: the eye, in the history of our species, making use
James Wong: of the collection, knowledge and tools that we expand upon
James Wong: every day. Now that this information is more available than
James Wong: ever, our next challenge is how to create a sustainable
James Wong: and respectful relationship between biodiversity and human progress to future
James Wong: proof our planet for generations to come. The journey really
James Wong: has only just begun. Next time on Unearthed from Kew.
Speaker 7: These leaf cutting ants, it'll make them climb towards the
Speaker 7: light whilst the fungus finishes off the insides. And then
Speaker 7: once it's finished eating it, it bursts out and produces
Speaker 7: this little fruiting body. It's drawn out and horrible.
James Wong: When did you last come in contact with mold, fungus,
James Wong: and the like? Chances are you're doing it right now.
James Wong: And your life's a lot better, thanks to this remarkable
James Wong: kingdom. Next time I'll be delving into the forgotten world
James Wong: of fungi, and finding out how little we still know
James Wong: about one of the most important and mysterious elements of
James Wong: life on earth. Plus, I'll hear about the surprising links
James Wong: between psychedelic mushrooms and our mental health.
Speaker 8: About 15 years ago, we decided it was time to
Speaker 8: explore the brain science of magic mushrooms. And I think
Speaker 8: my claim to fame that I've probably given more different
Speaker 8: kinds of drugs to human beings than anyone alive, but
Speaker 8: the good news is they're all still alive too.
James Wong: Make sure you don't miss it by subscribing on your
James Wong: podcast app now. You can share this episode with a hashtag #
James Wong: KewUnearthed and follow us at Kew Gardens on social media.
James Wong: Join in the conversation with the hashtag # KewUnearthed. I am
James Wong: James Wong. Thanks for listening.