Plastic Eating Fungi

Some fungi eat plastic. Could this be a solution to plastic waste?  While plastic-eating fungi offer a compelling approach to plastic pollution, there is more to the story.  On today’s show, we are addressing a long awaited topic on the interaction between fungi and plastic materials. From mycoremediation and degradation, microplastics, polymer science and ecological observations.

We welcome not just one, but four PhD students from Bayreuth University’s Collaborative Research Center (CRC) 1357 Microplastics. Among them are:

Yuanhu Zhang,  who has a background in Polymer Science and Engineering and is currently at the department of Macromolecular Chemistry II at the University of Bayreuth.

Julia Möller, from the Department of Animal Ecology I (Supervisor Prof. Christian Laforsch), University of Bayreuth. Julia has a background in environmental engineering and microplastics.


Stephan Rohrbach, an environmental microbiologist at the Institute of Microbiology of Leibniz University Hannover and is currently working on his PhD within the CRC 1357 Microplastic.

Gerasimos Gkoutselis, a molecular ecologist  currently pursuing his PhD at the Chair of the renowned mycologist Professor Dr Gerhard Rambold. Gerasimos is at the Department of Mycology at Bayreuth.

Join us and this dream team to get up to speed with how fungi and plastic interact in the environment.

Topics Covered:

  • History of plastics and microplastic
  • Defining bioplastics and alternatives to plastic materials
  • The pros and cons of bioplastics
  • The geometry of microplastics and how their forms impact how they interact with the environment
  • Potential impacts of microplastic on animals and the ecology
  • Current understandings in microbial responses to plastic substrates
  • Mycobiome of microplastics and why pathogenic species are more pervasive
  • Practical solutions for reducing plastics in our environment
  • What makes plastic difficult to breakdown
  • Predicting future applications of fungi and plastics


Show notes:

  • CRC 1357 Mikroplastik: https://www.sfb-mikroplastik.uni-bayreuth.de/en/index.html
  • "Microplastics accumulate fungal pathogens in terrestrial ecosystems”: https://www.nature.com/articles/s41598-021-92405-7.epdf
    • Press Release: https://www.uni-bayreuth.de/en/university/press/press-releases/2021/100-microplastics-fungi/index.html
  • More publications: https://drive.google.com/drive/folders/1AJ8k1JXDao2I-irUOqiFhwigWpVDhuA_?usp=sharing
  • CRC 1357 Mikroplastik Twitter:  https://twitter.com/SFB1357
TRANSCRIPT
Transcribed by https://otter.ai ** Subject to error
Alex 0:00
You my fellow humans are listening to the mushroom revival podcast.

Lera 0:05
Happy November friends. Today's episode we are addressing a long awaited topic on the interaction between fungi and plastic from myco remediation and degradation, petroleum chemistry microplastics pathogens. There is a lot in today's episode. So we welcome not just one but four PhD students from Beirut university's research center for microplastics. We have a molecular ecologist and mycologist and environmental microbiologist, an environmental engineer and animal ecologist and a macro molecular chemist with expertise in polymer science and engineering. So with all these specialties and plastics and fungi in ecology and chemistry, we hope that this does justice to the current state of affairs with fungi and plastic because it's a hot topic, many people are revved up about how fungi might help us with our plastic pollution problems. And we just really wanted to provide a realistic view on what's going on the capabilities what we actually know about this application of fungi.

Alex 1:16
You know, the dried settled drill fam, before we dive into the hyphal networks beneath the soil the review of the week. This one is from Elena Schiebel fantastic podcast, love, love, love all of this as a mycology lover. hat's off to you guys. So happy to find out. So happy to have found your station. We freakin love you Elena and every buddy else who is tuning in and tuning in to our fungal station. Thank you everyone. If you want to be featured on our show, leave a review. We'll pick one lucky review every single week and feature it on our show. The easiest way to do that is to go to Apple podcasts and leave a review. Please leave a star rating tell your friends and family that helps us a lot. Another way to support us is going to our site at mushroom revival calm we have a whole line of super delicious, amazing functional mushroom products. Right now we have tinctures. But in early November, we in the month of November 2021 We're launching the first world's first certified organic mushroom capsules, a whole line of super delicious mushroom powders. And the world's first certified organic mushroom gummies coming soon and we have a ton more products coming 2022 super exciting. bunch of blogs a bunch of awesome stuff on that. So head over we also have a special discount code. The code is called pod treat for our amazing listeners, we're not going to tell you how much you're going to save. It is a total surprise. You have to find out for yourself how much it is we change it all the time. Who knows. And now let's get into the remediation station on this mushroom station, plastics and fungi

so thank you everyone for being here all the way from Germany. We are in Austin Texas. So it's thank God for video streaming and audio streaming platforms to allow this to be possible. Now I want to know you know we have a big group call today so maybe one of the time if if everyone wants to give a little intro and who you are.

Julia 3:53
Yeah, sure. I'll start the voice said ladies first. So there I go. My name is Julia Mela. I am currently a PhD student at the University of bio Boyd's doing my PhD on microplastics in soils, and I am actually I have no idea about mushroom. But I am doing detection of microplastics in complex matrices like soils and compost. Yeah.

Lera 4:19
That's me. Thanks for joining us, Julia.

Julia 4:22
Thanks for having me.

Yuanhu 4:25
So I'm a PhD student at the Department of macromolecular chemistries at University of pirates also. And I'm currently doing research related with microplastics I synthesize polymers and characterize polymers. In the field of fungi plastic degradation, I provided a polymer materials for degradation test and I take physical chemical properties characterizations of the related polymer materials.

Stephan 4:56
Yeah, hello guys. My name is Stefan from the I'm working closely collaborating with Terashima on plastic accumulation of bacteria and fungus systems where I have focus on material parts. And we are especially interested in pigmentation behaviors and potentials and also biofilm formation. And yes, that's often.

Gerasismos 5:26
Yes. Hello guys. Also from my side, I'm very happy to be here. My name is Erasmus chrysalis, and I'm a molecular ecologist and also a PhD student at the University of pilot, currently under the supervision of a renowned mycologist, Gad, rhomboids. And I'm interested in all kinds of interaction between plastics and funghi, on organismal, as well as on a molecular level during experimentations, NGS analysis, and so on. And I'm actually the mycologist in this group.

Alex 5:56
Awesome. Thank you, everyone, for being here. And I think a great starting point would be the history of plastic. Right? You know, why? Why were they first made? Why did humans make them? When, and you know what, I don't know if you know the timeline of the different types of plastic made?

Yuanhu 6:15
Well, the first synthesized plastic was invented a bit over 100 years ago by a Belgian chemist, Dr. Hendrik Backlund, who use the phyllo format, formaldehyde reaction techniques to produce so called Bakelite. And he was also called the father of plastic industry. So why did he do this? Right in the beginning of 20th century, scientists wanted to know to bake some polymeric materials because they found natural reasons and February's are polymeric. It was during that time when backland jumped into the research of phenol formaldehyde reaction to produce synthesized or Amharic were cured materials to make money. And about 50 years ago, degradable plastics attracted interest and was produced since then. So we have all TAB TAB for our plastics, dated back to 50 years, the plastic industry boomed during World War Two, the so called PVC polyvinyl chloride was produced significantly, there was used as insulated cable living sheets, and polyethylene was invented in the 1930s, followed by printing in 1950s. So these two type of polymers, P and PP are the most used plastics, accounting for around 50%, the annual manufacturing. This is a basic time now of the plastic history.

Lera 8:07
And honestly, plastic is a wonderful material it has given us properties we couldn't find anywhere else. And an inexpensive way. You know, we've got flexibility and elasticity, cheapness, inertness, there's all sorts of wonderful things about these polymers. But of course, we're not treating their afterlives very well, by throwing them into the landfill. And they're showing up everywhere. I mean, the literature that you guys shared with us that the fact that we are seeing microplastics nano plastics Meza plastics in the air that we breathe, the water we drink, it doesn't seem to not be anywhere anymore. Everything we consume has some trace of this material. And I mean, what a dream team to have all of you together, teaming up on this, defining it, and then looking into the effects of the microbiomes surrounding it. So before we dive into exactly what your team is doing, why come together? What what are the alternatives that exist for petroleum based plastics and why are they so difficult to integrate into today's society?

Yuanhu 9:24
I guess I can also answer this question because I'm the only one from the polymer sciences. Yeah. A very good alternative is the bio plastic for the conventional plastic. But let me clear here the definition of the bio plastics can be confusing because they not only refer to bio based plastics, but also biodegradable plastics, and the bad based plastics, of course, those from renewable biomass sources like vegetables, corn starch. Dust and natural polymers like centers and proteins and biodegradable plastics refer to those that could be degraded by living organisms, for example, POA and PBIT so called ecoflex has that brand name and the bank based plastic to lock mean degradable and by degree the plastics are not necessarily from based on materials also. So, compared to conventional plastics, the plastics has some advantages of course, the first is the use, they don't use the petroleum oil. So, there is less petroleum oil consumption and also in some cases the plastics are even more stronger and lighter compared to the conventional plastics. And, and of course, more importantly the less plastic pollution because of the biodegradability. And the disadvantage could be the plastics are more expensive considering their sources and they could compete with food sources also. Let me highlight the last point is the bioplastic cannot degraded in all natural environment. So, we, for example, even in the compost, our recent research found degradation of the air degradable plastics in compost is not complete. So, using plastics doesn't mean one could throw this materials at well, we we should always remember proper handling plastics either for the conventional or view plastics is a super important aspect for reducing plastic pollutions. So, it's it's like a double edged sword right

Alex 12:04
and by the grip almost, to put this point a little further, we're in the mushroom growing industry and most mushrooms are grown out of PP five or polypropylene number five bags. And they're great bags. You know, they're very high heat resistant, and they work really well for growing mushrooms. But polypropylene number five is incredibly, I think impossible to break down microbially or it'll take 1000s of years. So the alternative people have been using Oxo plastic, I think is that the correct terminology. And basically, it's from my understanding, I'm not a plastic scientist, but there's certain chemicals or enzymes in the plastic, which has it break down. But the problem is it breaks down into microplastics, which is the whole theme of this episode. So it sounds great. And it they they throw the name compostable on, you know, on the label, but really, it's actually probably making the problem worse. And then another thing I was reading is that, you know, these bio plastics, they sound very eco friendly, but a lot of people will put them in the recycling bin. And then when when industries will are looking to recycle regular plastic, it messes up the recycling. And we were actually interviewing a local recycling company. And they said, Yeah, this is a terrible problem, because they have to throw out whole batches of plastic that they're looking to recycle because of this bio based plastic messing with the chemicals or something. And it's actually a huge problem. So, you know, we haven't figured out alternatives to petroleum based plastic yet, but we're working on it. And I love you know, there's fungal based alternatives as well like myco works, or Ecovative are a lot of companies working on alternatives to Styrofoam and things like that. But the problem still lies on plastic that we already have in the environment, right? So they start to degrade, they make something called microplastics, which I'm sure I hope most listeners have heard about microplastics while they're terrible, so why don't you guys give a little backstory for people who have never heard of the term micro plastics, what are they where are they coming from, etc.

Julia 14:29
All right, I think I'll jump in here. So microplastics are commonly defined as plastic particles smaller than five millimeters, but they go down to like the lower micrometre range and then nano plastics are even smaller. And where they come from is, I think for here we need to define between primary microplastics and secondary microplastics. So primary microplastics are plastics that are intentionally produced as very small plastics. and they were used, for example, I think the most common example is the abrasive that are used in the peeling creams that you use for beauty creams. And they were added there as an abrasive to make the skin smoother and more beautiful. So that is primary microplastic added to product, whereas secondary microplastics are plastics that come from larger plastic products that somehow fragmented either in the environment or due to mechanical abrasion into these microplastics. And, yeah, I think, at least here in Europe, the primary microplastics were like the, the thing the, you know, most people looked to to avoid in order to reduce microplastic pollution, but the main pollution actually comes from the secondary microplastics that come from larger particles, for example, due to littering, which is a major, major problem throughout the world. Also, tire abrasion, you know, the rubber that comes from tires, also is a massive input of microplastics into the environment. And also fibers that are shared from clothing while we wash them. So if we have synthetic clothing, we will also shed synthetic fibers, which are then classified as microplastics. So yeah, there is a lot of input pathways into the environment. And the ultimate source is us humans human population.

Alex 16:34
I was so surprised that all the places that microplastics show up, I mean, it's literally everywhere. I mean it from, I mean, plants can absorb them there, it's in salt, beer, I think sugar was on the list. Even in the air that we breathe, I think that was the most surprising fact I had no idea. You could breathe in microplastics, I just thought if it was only in the ocean, and the fish eat, we eat the fish. But I had no idea how abundant microplastics actually work. So that was insane to me, and I'll never look at dust the same. Now learning that there's a lot of microplastics and dust. So when you're dusting, maybe it'll fall in your food on surfaces, things like that. That's insane. It's pretty crazy. So I was also reading there's, there's all these different shapes to have microplastics. And, you know, microplastic seems to be a general term, you know, for for anything under a specific size. But you gave so many examples of, you know, in like a facial cleanser, they seem to be like spherical, but you know, nano particles of your clothes, they might be threads, I was also reading that they could be bubble shaped, or all these different shapes are there? Is there one that's more toxic than others? Like a thread shape is more toxic than a sphere? Or? I'm guessing that microplastics are also made of all different types of plastics as well. So is there one, that's the worst that you have to avoid the polypropylene threads or something like that?

Julia 18:22
To be fair, that is exactly what we are trying to find out right now in the CRC. So as a scientist, I have to say the data is still inconclusive. But yeah, it's true, like micro plastic is not does not equal micro plastic. It's not the same thing. It's not like when you talk about authentic, it's one substance. So we have a lot of substances with a lot of different shapes. Like, yeah, as you said, fibers or foil shapes. And all of them, like, do impact the environment and organisms differently. So how exactly the the effects? Anything is, is still being researched? So I can't actually answer that question right now.

Lera 19:04
Well, thanks for doing that research. I know geometry is huge on the micro level of things. So you know, when surprised me that the physical form of an identical polymer could be way more destructive than another. So perhaps you guys are investigating it. But we do know that there are some repercussions to microplastics. And your team did contribute to parts of this. So yeah, could you just discuss with what we do know about how they're toxic for us? And some species of animals that seemed to disrupt their circadian rhythms, whereas in others it didn't. And are there any other Stark examples that you guys have found in the last few years?

Julia 19:52
Yeah, here. We have to be honest that a lot of the the ecotoxicology studies that were done were conducted with very, very high levels of microplastics. So, here, the there were always negative effects on, for example, the muscles that were fed were led into an aquarium with a lot of microplastics. And here, you did have negative effects. But on an environmental or environmentally relevant level of concentration, the data is still very inconclusive. So there are like some, some animals show negative effects others did not. Even with the same animals, sometimes they had effects or not, depending on the concentration, and obviously also on the plastic type plastic form. What I can say here is that, especially plastics that are that have a lot of additives, like for example, softeners, that are known to be cancer genic, for example, plastics that do contain these, for example, PVC, they will definitely have negative effects on on animals, even in environmentally relevant concentrations, I guess,

Alex 21:16
and would have to think I don't have the exact statistic in front of me. But I was reading that, I think it was around the 1930s, the annual production of plastic was around a million tonnes, I think it was then. Not too long ago, it was over 300 million tonnes, something like that, I think was 360. Yeah, which, and that was an incredible increase of production. And I would imagine that what's environmentally relative now will be minuscule compared to 40 years from now, right. And so the super high levels of the muscle test that might be very environmentally relevant and say, 10 plus years or so, when we have increased production of plastics, etc. Hopefully, that doesn't happen. But, you know, this is something that we have to anticipate as being relevant in the future. Right. So, you know, it just shows how little we know and how potentially incredibly scary that is. Yeah, considering how how invasive this problem is, and how, you know, it shows up everywhere. So we should get ahead of the curve and do as much research as possible. What do there? Are there any solutions that exist currently for cleaning up microplastics? Or is it pretty difficult? Because they're pretty much everywhere and so tiny?

Julia 22:53
Yeah, it is. I would personally say pretty much impossible to get rid of the micro plastics that are already in the environments at begin without destroying the entire environment in the process. So I think the goal we should be aiming at right now is not to get the plastic out of the environment, micro plastic plastic, yes, but not microplastic. But we should stop introducing plastics and microplastics into the environment. And there are so many ways you could do that. waste disposal is such an essential thing. And we should, yeah. waste disposal, recycling are two major issues we should tackle. In order to reduce our plastics input into the environment.

Lera 23:43
It seems like the first responders to a new substrate in the world is always going to be micro organisms. They're the ones that are dealing with this kind of face to face, you know. So in your studies as a team, are there any direct evidence that you have of noticing microbes change their metabolism to get into some of these plastics, so petroleum, a lot of this is naturally occurring, right? We mined it from the ground, it's, it's a natural substance. And there are organisms that can work with this material and metabolize it. But then humans take take this oil and we process it, and a number of different ways to create some other polymers that do incredible things in our day and age. How have you seen the microbiology respond to this if at all?

Stephan 24:45
So relating to ingestion of the state of Nebraska, so, like Oklahoma, new homes or daphnia. We could see that after introducing microplastics and then the early penalty was increased that Also their metabolism was definitely, you know, affected by plastics. So you could see that other enzymes were more abundant or less abundant in metabolism. And this is like closely related to, for example, gut microbiome. They're also because you have to imagine you have like a gut system, it's an equilibrium of microorganisms. And when you're entering their plastics, and you have a completely different surface there, which is huge, because it's so small there. And also, you can add to the already said, additives, or add vaccine biotics for the environment, which can really attach to the surfaces, and therefore you can really influence the microbiome because some bacteria or some other microorganisms can either know that more or faster this new habitats, and have rolled to it. And so you have changed the equilibrium there.

Alex 26:05
That was, that was one of the most fascinating things that I read about how these microplastics destroy the the gut microbiomes of some organisms, and how that it had a huge effect on immune system function, right? I know, in humans, our gut, you know, about 70% of our immune system is supported in from our gut microbiome, and from your research on pathogenic fungi, you know, being super intelligent and, and sliding into that lifecycle of microplastics, you know, Cryptococcus, you know, finding its way on microplastics. And then, you know, getting its way into other organisms, specifically humans. If, if it is also destroying the gut microbiome of organisms to have a suppressive effect on the immune system of organisms, Cryptococcus and other pathogenic fungi can slide right in. So it's, it's evil. You know, it's almost like an evil mastermind of these pathogenic fungi to slide in there, almost at the perfect conditions. It's, it's, that was mind blowing for me to read that.

Lera 27:22
Yeah, I would like to get into that a little bit more, because one thing that your team seems to have more extensive research into is how these microplastics foster pathogenic fungi and I'm wondering, what's the mechanism here? Why are pathogenic fungi in particular, able to take advantage of these tiny little plastic temples is kind of how I'm thinking about it. Right? You know, what, is there? Some chemical attractant there? Or you know, why, why aren't we seeing so called beneficial fungi or bacteria colonizing these these microplastics?

Gerasismos 28:07
Yeah, I think that's a very interesting question. But it is not that straightforward to answer it is rather, yeah, you have to see from from the one person from the plastic centric perspective, and from the fungal perspective, on the one hand, plastic is hydrophobic, and in a hard surface, in in the environments, and on the other, you have the pathogens, the funghi out there, we found a lot of pathogenic fungi because actually funghi in the environment, and particularly pathogens prefer an attached lifestyle over free living one they live, for example, associated with human skin or with the plant cuticle. And yeah, plastic actually resembles the natural habitats. And yeah, these pathogenic fungi came in here a spectrum of biological properties that allows them to mix them pretty tight to really colonize what is called the plastic sphere. For example, the form biofilms, they produce invasive structures of like upper storey for example, they have general invasive growth, they produce melanins, which are also responsible for invasiveness and yet allow them to colonize extreme substrates or new ones like rocks and other surfaces and also plastic and also filamentous funghi, which were the most abundant ones we found in the plastic sphere produce a molecular AutoPro Murphy, which is called hydrocarbons. Those are small hydrophobic proteins, which help them to assemble on hydrophobic surfaces and allow them to really adhere to those like plant particles but also to plastics so from an ecological as well as from a biological perspective. fungal pathogens seem pretty signs colonize plastics in the environment.

Alex 29:58
In one paper I was reading There is a quote, and it said, between 34 and 127, distinct fungal ot use, which is operational taxonomic units, which I would love for you to define, could be identified within a single plastic sample, which blew my mind and I tried to Google ot use, and I still am not. I don't have a full understanding and is that species or what is in OT you?

Gerasismos 30:29
Well, I'm an OT you operational taxonomic unit is basically a species, Proxima based on sequence similarity, when you try to find, for example, how many species of funghi are in a sample of soil or a plastic sample, and you do sequencing molecular analysis, you try to delineate to tell apart species based on a particular marker gene, a particular part of their genome of the sequence of the DNA. And we've done so by taking a marker gene, the so called it s, internal transcribed spacer, which is actually the state of art marker gene for funghi. And by analyzing the sequence similarity of the different funghi, we found, who could tell apart species that were found on plastics, so basically, yes, you can call them working species what we have, and yet, there were quite a lot.

Alex 31:21
That is way more than I was expecting. I, that blows my mind. And I'm curious, it seems like the majority of those were pathogenic fungi. But there were, you know, saprophytic fungi, there's all different types. What, what did y'all find? And what has been found, period, you know, being growing on these microplastics or macrobiotics?

Gerasismos 31:46
Yeah, very interesting question. And yet, we were also very surprised to find these pathogens, we were actually just looking what is there in general, because this was the pilot study the first time it has been done for terrestrial systems, and yet also for aquatic systems. For my knowledge, there is nothing about fungal pathogens that colonize plastics. There's nothing known. Actually, what was characterizing the plastic sphere, as you said, were crypto cocoa funghi, like yeasts or cryptococcal. Yeast and black funghi. From the class of two to my seeds, which are actually filamentous funghi, that produce a lot of melanin and that are known to invade and penetrate into surfaces of rocks of walls, for example, in houses, and yeah, which are often found to call to cause diseases, so called Ferro high for mycosis, which are actually melanin induced diseases from funghi. In humans, this is actually what characterize the plastic view analyze.

Lera 32:48
Yeah, that have knowing that the crypto cockle genus is the one that's thriving the most on microplastics does not give me peace of mind. We just interviewed a medical mycologist, who studied infectious fungi. And Cryptococcus was the single most destructive fungus in terms of human disease. So I'm maybe it's too soon to tell, but have you seen these species? sort of ride this, this microplastics spaceship through our industrial processes? And, you know, do you find this in our beer? Do you find it in the water? Do you find it in the air? Or are these colonized microplastics more present just in the topsoil? Or, you know, anywhere else? Like where were you finding the most concentrated Cryptococcus pathogenic fungi?

Gerasismos 33:44
Well, actually, as this was the first one, we can't tell if Cryptococcus are different, other pathogenic fungal genera can be found on plastics all over the world. But it's highly conceivable assuming that from an ecological and biological point of view, their precious time to colonize. So it gets this is something that happens on a global level, whether it is I mean, whether the plastics found in the soil are more colonized than others needs to be investigated. This is just the starting point initiation point of the research in this regard. But yeah, I can think that I think that pathogenic family will colonize plastics everywhere.

Alex 34:26
And this specifically was in a village in Kenya, correct? Sorry, sir. Yeah. Yeah. And I think I read that there were more fungal diversity in this soil than there was in marine plastics, is that correct?

Gerasismos 34:46
Well, yes, from the one side or on the other, you have to admit that it is really difficult to compare between different ecosystems as sampling techniques, extraction, and all other following processes are very difficult to compare. But yes, if you put that aside, yes.

Lera 35:07
So I could see someone thinking, okay, these species of fungus are adhering to the surface of the plastic, which means there's some protein binding, which isn't too far off from metabolism. So are you seeing any metabolites from these fungus that are attempting to degrade these microplastics? And if not, why not? And do you ever think that they will? Or is this something you'd expect from a different genus? Or maybe even bacteria and fungi are not the answer.

Stephan 35:42
So I can jump into this here. So actually, in this study, we didn't focus on liquidation analytical distillation. So for this certain Caicos finding here, it can't say anything about Buddhism here. For other studies, they are known that when you have, you know, mathematization, or imitation processes, on the one side, it's not clear often if it's just from additive, or from rich research, plastic material there, because also the study from our group, from OCLC, which say that you'd say, like UV radiation of awesome, great impact on a periodic degradation. But when you would have an easily degradable plastic, when you wouldn't have a problem of microplastic, because then a degradation will take place, you know that in a year or less time, and then you couldn't like discuss about it. But what we can say is that we see attachment. And this attachment might be following some regulation, but trust us today not fully understand or movement difference really coming from the polling their molecules itself without any treatments there. And also for, you know, when we think about if it will be in the future, we talking about so large ages here, which it's hard to predict, I mean, we could assume that it will happen at some point in evolution, but for now, we all know is that it will be like in the very near future.

Alex 37:18
Probably that the most famous example of plastic degradation that I I'm aware of that hit big media, at least here in the United States was, I believe it was 2013, when researchers from Yale went to the Amazon rainforest in Ecuador, and did some endophyte samplings in in the Amazon there. And they found a species of fungi P microspore. And they brought it back to the lab and they found that it could partially degrade polyurethane. And this was big news at the time, and it hit a lot of big headlines. And they did grow this this fungus in a bioreactor. So liquid culture, and it was able to partially degrade polyurethane in record times compared to other things, which is still very, very slow and not that impressive, but but more impressive than than what exists. But my understanding is there's lots of things that degrade polyurethane from UV light to lots of strains of bacteria. And it seems like from my limited research, polyurethane is the only type of plastic that has been found to be degraded by fungi, but it could be wrong and I hope I'm wrong. So are there other types of plastic that have been found to be able to be degraded by fungi and other like organisms like bacteria and, and things like that?

Gerasismos 38:56
A crucial question. Basically, what you said about polyurethane, we've tested ourselves we've isolated funghi from the plastic we sample in siia in Kenya, and tried to also see whether they do like an initial screening phase of plastic biodegradation, also using polyurethane and over 80% of the strains could partially or fully degrade polyurethane in optimum condition, of course, which seemed Yeah, impressive, but somehow, okay, it's just poorly retained. But if you go into the literature, you can see that many fungal species have been tested like Alternaria alternata, are also Fusarium oxysporum. Both funghi were also found in our study, and they've shown that they can degrade plastics, like mud, but not to the full extent. Like there is no mineralization and assimilation, what has been reported until now. So my knowledge at least is that surface modification and stuff and also weight loss, abrasion and also fragmentation. such things such processes happen and fungal are part of it, they do it, but the full extent of biodegradation, but funghi any different type of plastic? It's not been shown yet. But this is something we're currently doing a research on, there's a lot going on with, together with Stefan and Hannover, we currently focusing on that as well,

Alex 40:23
when you said fragmentation, are you implying that they're potentially making microplastics? Are you? Are you implying that they're making the problem worse? Are they the cause of this?

Gerasismos 40:34
You got me there? No, I'm not saying that we are not. There's no evidence of funghi, making microplastics. But what we found from a lot of microscopic analysis is that the funghi colonize or prefer, presumably prefer to colonize fragmented surfaces. But this is, I guess, because they prefer surfaces that are rather raw and on not too smooth, because there's a lot of surface mites easier for them to colonize. In some ways. I don't think that they are causing the microplastic. But they prefer to live in fragmented surface areas.

Alex 41:13
I see. Yeah. And, you know, if they're able to degrade, you know, parts of the plastic, what, what are the byproducts if it's not, you know, nano plastics, if they're not just breaking apart into smaller bits? Are they chemically breaking it down into what co2 Or what are the byproducts of that? If you know,

Stephan 41:40
so here is, as we said before studies for complete liquidation, so the complete degradation would cause and co2 If pollution there, but you know, at some point either internally in the organism itself, metabolism, that's probably like the mass of the plastic, and also some byproducts of that and our processing to include metal Buddhism, you know, and, but this is also not investigated so far. That's to give to bacterial samples, because they asked for other organisms. Also, it's important that they can read completely polyethylene terephthalate. And then you can really found the monomers of the retrieval bacterium there. But it's very hard to really focus on single monomers of metabolites from the whole process, the whole topic.

Lera 42:41
I'm curious if you have ever investigated, breeding fungi to be better to graders of plastic? Or maybe even bacteria? Because it seems like there could be some real potential here for application maybe even industrially, I'd love to get your opinion. But I would also love to hear you speak on the fungal metabolism potential. I mean, from my understanding of fungi, they are like, professional eaters and chemical makers, right? So if you could kind of like walk us through the fungal point of view, you're meeting this new plastic material. Maybe you don't have the metabolism to digest it right now. But you're going to experiment, right? You're going to throw some Spit here and there some enzymes see what works. How are they doing this? Is it in their genetics and their gene codes that they're just tapping into different parts that weren't previously manufactured? And then testing it? I mean, what what do you know about this?

Gerasismos 43:48
Well, maybe yeah, just a real, a real quick tap into the funnel world, actually. funghi are extremely powerful and versatile bio catalysts. And in their entirety, they can degrade any polymer or any biopolymer on Earth, even recalcitrant ones likely lignin even and year form the decomposers, the major decomposers on Earth, and they do that by means of a wide range of oxidative EXO enzymes, which they secrete into the worlds and so decomposing depolymerize polymers into smaller units, which they can then internalize incorporates by means of diffusion. This are words that are small drops. And yeah, you can imagine like this is why fungi especially interesting and that's why maybe the term plastic eating is also a little bit confusing, because there's actually no ingestion procedure but rather something that happens extracellular and then is incorporated if provided the substrate can be tropically exploited. And what makes funghi particularly interesting and could make them the biological capacity in plants. Stick biodegradation is that they have unique features of or the follow way of life is unique in a way that if you have that dynamic, ethically and branching mycelium, which is exploring through the best substrate, for example, the sword, it can really thoroughly explore the environment, the contaminated environment and go into pores into mash works of soil, for example, to find the plastic. And this is something for example, that bacteria do not do this is something unique to funghi. And once for example, the hyphae have encountered the plastics provided they can really by metabolic station or capitalization using their extra enzymes exploit the substrate. Yeah, they can wonderful one plastic it to another in produce balance, they shift from explorative growth into explosive growth form and my then produce a biomass and in principle, be able to degrade the plastic in a way that's somehow efficient in if that's ever possible. And I think that's the unique selling point of our funghi in the plastic biodegradation debates. And maybe this is what makes them promising in this whole issue because they have a unique form of life, which could make them the ideal natural decontamination, machineries for plastic.

Alex 46:27
And from an industrial point of view, because I'm, I been studying micro remediation on and off for a few years now. And I'm just blown away at the large scale applications of micro remediation, or using fungi to degrade or whatever the mechanism any see no toxins in our environment. And most of the time, if not 99 point 99% of the time, they're using genetically modified organisms, right, that are more can produce more of these, you know, ligninolytic enzymes are whatever it may be. And so that's step one of creating the super strains, right? The second would be, we have so much plastic, I mean, 300, and would you say 60 million tons. That is incredible. And that's what all the recorded amounts, there's probably a lot more that are unrecorded. To tackle that the scale is mind bogglingly huge. And so a lot of times this remediation is done in these liquid bio reactors, right. And I can't even imagine trying to tackle 360 million tons in these liquid bio reactors. It doesn't really sound feasible to me, although maybe at a smaller scale. The other thing that comes to mind, especially when these headlines were coming out about this P microspore. Especially because it can exist without oxygen. They thought oh, you could put it underneath these landfills, you know, in these environments that didn't have oxygen. Another thing that comes to mind is creating these immobilized enzyme spray and spraying it on landfills. But there could be a potential that could make more micro plastics, potentially. I mean, I'm just spitballing here. I'm sure this is your day, day in day out. How do you imagine we we tackle this this feat?

Gerasismos 48:38
Yeah, good question. One crucial question. Of course, when I first started to work with funghi with regards to plastic and plastic degradation, I thought the same thing, screen a lot of fungal strains, find some ligninolytic enzymes that may be suitable for degrading plastics as well by isolate them by engineer them artificially put them in big tanks to make bio reactors put all the plastic inside and outcomes, something useful, something that's not so bad for nature. But the truth is, I don't think that's commercializable order are somehow used to industry because who gets down to the ocean floor to get the microplastic out who gets down so many soul horizons or into the Arctic ice or the stratosphere to get the microplastics I think that even landfill having landfills is I wouldn't say a bad thing. But you consider more elegant solutions because one, it's in a landfill that microplastics can easily come into the environment. Actually landfills are sources of microplastics that later accumulate in the environment. And I don't think that it's so easy, it would be nice, but I don't think so it's avoiding plastic, and hopefully in 500 to 5000 years funghi which are really everywhere. They also be kids this trade they share with microplastic they may adopt insofar as they somehow efficiently The great plus in a way, but the input needs to stop needs to be turned.

Alex 50:05
Julia, I know you were starting to talk about this. And you you said, you know, it's impossible to tackle the microplastics that already exists. And it seems it sounds like you've already been thinking about this, I hope I would imagine. So what are your thoughts of, you know, this is your line of work of seeing microplastics in the soil and oceans and things? How do we stop that initially? Is it lined landfills? Or, you know, what, what's your thought process?

Julia 50:34
Well, we in Europe don't have landfills anymore. Oh, that's awesome. Yeah, so actually, we mainly burn plastic, which is also environmentally critical. But on the other hand, at least we get energy out of it. And so that's one of one of the the main things that the plastic industry also says, you know, you can recycle plastic, or if you can't recycle it, you can burn it and use the energy that comes out of that. So that's one of the major issues that I do think we need to tackle is, is plastic waste management. And also just plastic collection for recycling is also something that we need to enhance and make better that the infrastructure is is there globally. I mean, we in Europe are very, you know, privileged. But if we look to to other countries in Africa, and India, the logistics aren't on there. So I do think that if we tackle plastic waste management on a global scale, we could we could really, really reduce plastic input into the environment on a major scale. And it wouldn't be that difficult to do, you just need a couple of resources. And governments that pool with you.

Alex 51:53
I can't tell you how many countries I've been to where it's such common practice to burn piles of plastic, you know, in your backyard, because there is no infrastructure. You know, there's no recycling day where someone comes around and picks up your trash or recycling. If you want to get rid of your trash. There's no such thing as recycling, you burn it, you make a pile in your backyard, you light it on fire, that is in so many places, what the only thing that exists. So yeah, having that infrastructure would be amazing. And are you You talked about industrially burning plastic for fuel, it sounds like there has to be some economic incentive to to make this infrastructure right. And it sounds like that might be a incentive economically, do you feel like having some sort of air particle filter to capture the microplastics to prevent them the microplastics from entering the the atmosphere like Do you Do you feel like that could be done environmental in an environmentally friendly way? Or what kind of structure what kind of structure do you imagine globally as being the best or if you don't know and we're still figuring out that's also an adequate answer.

Julia 53:17
Yeah, I'm obviously Incineration is there's incineration and incineration so burning plastic in your backyard is definitely not a good idea. Simply because of the the toxic gases that are released during that burning process. So I do believe that large scale incineration plants, not only for plastics, but but for household wastes in general are a good idea. But the thing is, you have a small part that is the incineration and a massive part on the back that is the gas cleaning process in order to not pollute the air. And so yeah, obviously it can be done it is done. And then you know, the the cleaned air at the end contains co2, maybe water and that's that's it. And all the rest, then actually also goes to landfills, which is not ideal, but we have no other option. And so, yeah, that I believe that that's the option we have at the moment. I'm not sure if it's the best option. So I believe there can be more you know, humans are ingenious, so I'm sure we can we can manage a better, better process in the future. But that's the one I see at

Alex 54:48
the moment. And potentially we can combine these two approaches right of of industrial incineration and then using fungi and bacteria and other things to help with that cleanup. process, right, so creating an in economic incentive for creating fuel and energy, but then also using microorganisms to help with that cleanup process. And I'm sure the the end products are of less or less to clean up, then they pre burning. If that makes sense, that was a weird way to say it.

Stephan 55:26
I think it's just very important to separate the three different types of plastic because as we were before, some kinds of plastic are more easily degraded than others. And so when you can separate them to each other benefits would be more feasible to make something like a pie wrecked on a smaller scale there. But also, there's a problem in like the thought you have, there's no damsels in Europe. But I know from field experiments, you don't have these classic dancers, but from the municipal base because of beds, a separation, you're still plastic in there. And then it's just like thrown waste plastic. And I mean waste of space in the end. And so it's also a huge part of the human that we have to change our behaviors.

Lera 56:12
So we won't who you could speak to this, but I'm just curious if you can describe in simple terms, why plastic is so difficult to degrade? I mean, what about this, this chemical is so hard to unlock,

Yuanhu 56:29
because microplastic are composed of polymers, and these polymers are made from some carbon, carbon, carbon hydrogen resources, chemicals, and this carbon carbon compound is it's very difficult to is very inert and resistant to conditions like temperature and humidity. And also you'll note in the environment, and this is the good aspect for the plastic, it is light, and it is persistent, and durable, also. But it the bad aspect, of course, from now, resulting in the problem. environmental problem is causal. It's good properties.

Alex 57:30
Yeah, I'm not a chemist. So this question is, you might laugh at me, but bear with me from a layman's terms, my understanding of how fungi work, and you were just talking about this on this nonspecific action of how, you know, they work with a free radical mechanism in which the free rock radical oxygen, my understanding is it binds to these molecules and basically rips them apart, right? If I'm wrong, just let me know. But that was that was my understanding and how, you know, this fungal degradation worked in terms of plastic is, are the free radical oxygen? Are they not able to pull these compounds apart? Because the bonds are too strong? Or? Yeah, I'm trying to understand it from someone who is not a chemist.

Yuanhu 58:32
Yeah, absolutely, because this is not the way that polymer or late we need to introduce free radicals to the smaller polymer, so called polymer and this is the building block for polymer and polymer is 1000s 10s of 1000s of repeating unit of this monomers and the monomer which contain free radical in one at one end of this bond can can initialize another monomer. So, then, this prolongation of this polymer can can proceed and in in the other way that when this once the polymer formed, the like you said the three radical oxidate is not so strong enough to to cut off this by the pond and which is too strong and too inert. This other chemical compounds that's the reason would make it more very inert and stable.

Alex 59:52
For use, it seems like because we're able to recycle a lot of plastic it seems I'm guessing they use really harsh chemicals to break that bond or something. This is or is there an industrial technique to break down say polypropylene number five? Is there an industrial technique to break that down but it's really toxic? Or how is that what we're trying to figure out?

Yuanhu 1:00:25
Yeah, yeah, um polypropylene and polyethylene are one of the most difficult type of polymers to degrade data, because they consist of only carbon carbon backbone. And, and for like, for the Pawnee, Easter's which consists of Eastern groups on the backbone, which can be hydrolyzed by like Amazon or other Kinkos. So, this is the type for the biodegradable polymers. But for the polypropylene and polyethylene, it there is not a very good way to do it is still our problems. And Sundays have to pay more effort and their time in this field.

Lera 1:01:21
So picture this carbon backbone, as if each carbon atom is an industrial strength magnet, it's super easy to get them to bond and stick together, but pulling them apart, not so much. It requires a lot of energy. And getting that energy on the micro scale to pull these carbon bonds apart is no easy feat, even for the incredible kingdom of fungi. So far,

Alex 1:01:48
this analogy helped me a lot. You know, we're having a discussion after this interview, and I was trying to wrap my mind around. Is it so funny how relatively easy it is for humans to make plastic? But breaking it apart is so impossible, or seems to be impossible for us? And isn't that such a funny conundrum that we're in, we can make it, but we can't make it. And so I think that magnet analogy helped me a lot. And hopefully it helps our listeners, you guys are up against quite a feat. And I'm super grateful for for your team of tackling this because it's monumental. I mean, the problem is everywhere. And if it affects all living organisms, I think I would assume it affects all living organisms from many different kingdoms. In some way, some I guess, you know, Cryptococcus benefits from it. But but other I would assume most organisms, it's detrimental for for their evolution. So it's, it's huge. It's a huge feat to tackle. And I'm, I'm really grateful for your team, doing it and figuring out these really, really difficult questions.

Lera 1:03:07
Yeah, and if there's anything, any of you for want to share that we didn't touch on, just with your personal research and with your team's research, now's the time we welcome any of that any prompts for our listeners to continue investigating, and maybe even go into this research themselves?

Gerasismos 1:03:26
Guess you've covered the most important points of research. And we are very grateful that you invited us to talk here. It's very nice that you share awareness of such important topics with other people all around the world. And now I'm a keen listener to your podcast. I must admit I have listened to so many, and really like it. Thank you for inviting us once again. Thanks

Alex 1:03:46
for listening.

Lera 1:03:47
Yeah, thanks for being here

Alex 1:03:49
and talking and being a part of it.

Stephan 1:03:51
Thank you for inviting us to your podcast here.

Alex 1:03:55
Did you know that Legos are made using something called iconic acid, which is produced by a fungi, and one day, we'll use fungi to break them down so you can save your vulnerable little feet from ever stepping on one ever again.

Lera 1:04:15
It's one of my favorite fun facts about the fungal kingdom. They're even in your Legos. So big thanks to Babe Ruth university's research center and to our four PhD students who so generously gave us an hour of their time all getting all of them together to discuss this topic. There is a whole slew of shownotes where you can read more about this institution and the wonderful students working on it, as well as their publications and more links just to learn more about this vast and potentially super important application for fungi.

Alex 1:04:52
Big fungal hug to all of our listeners out there. We literally could not do this show without you. So as always, much love And then the spores be with you