 Thanks very much Bruce. I wish I could say that that was just around the corner But I think we are making steps in that direction, but we're not quite at growing cars right out of the ground But I'm very excited to to be here today to tell you a little bit about The work in my lab that involves both renewable materials and renewable chemistries that come from plants and two two areas I'm going to discuss are Metabolic pathway discovery and engineering and in this context we're interested in small molecules both for human and for plant health And the other and I want to talk about is using plant biomass directly to make biobased and renewable materials So specific stories I want to to tell you about Have to do again with small molecules and large molecules from plants. So small molecules here Are represented by this compound called the toposide. So this is a clinically used anti-cancer agent That's derived from a plant molecule. So the gray part is the synthetic part and the rest all comes from plant chemistry And of course again, this is a compound that's very important for human health And down here on the bottom. I have a molecule looks very different This is a model of lignin, which is a polymer a major component of plant biomass This polymer is used by plants for structural support and protection And we're trying to find figure out new ways to use it for materials So these two things this small molecule up here for human health Pharmaceutical and this biopolymer that comes from plants might seem very distantly related So so why am I telling you these these two very different stories? It turns out that they're not so different to the plant right So plants are are very ingenious in using their metabolism in in all different kinds of ways So it turns out that this molecule and this biopolymer are actually come from the same roots of metabolism So you can trace back this blue part to these phenylproponoids which are derived just from primary metabolism And the molecule phenylalanine. So this is a I think a great example of how Plants use something that they have to have to make proteins and they can make compounds important for their own health And turns out for human health and biopolymers that we use to make materials So within these these two niches of metabolism, there's different kinds of engineering questions So their first when it comes to small molecules relates to how can we build these pathways? What are the components necessary to perform metabolic engineering so that we can copy the chemistry that's found in nature and Possibly make new and more active derivatives And down on the bottom in the context of lignin plants actually are really great at making tons of lignin I'll tell you in a little bit It's the second most abundant biopolymer on earth And so we I arguably sometimes we would like to make actually less of it So there's plenty of it around and so the question here is more how can we use it rather than can we make more? So I'm going to start with this this bottom story of how can we use lignin to make renewable materials and our efforts in this area are Really part of a collaborative team on campus here We affectionately call ourselves the the green team So these are a group of faculty students and postdocs as well I don't have all their pictures shown who are interested in generating renewable materials and so this is not a comprehensive Listing of everyone involved, but some of the work. I'll talk about today involves Sarah Billington Who's a structural engineer Craig Crittle an environmental engineer Kurt and myself both from chemical engineering and Bob Weymouth? from chemistry and Again, our vision is to be able to use monomers derived from nature that are renewable assemble them into polymers and then fabricate materials that are indeed renewable and so we're not just Involved in this front part of the process But are also very interested in ensuring that this is a sustainable material cycle that the materials we make not only our high performance but can be reused through end-of-life disassembly and reassembly This kind of cycle all relates To finding a way to shortcut a much longer petroleum based carbon cycle, right? Of course, this is a renewable process. It just takes a really really long time And so where we're focusing our efforts are on shorter cycles that come from biomass to make renewable materials Now as I mentioned one of the biopolymers that we've been focusing on is lignin and Many of you might be familiar with lignin But to give you a little background. What is lignin and why do we care about it? This is a sandwich structure of a plant cell wall here And there's actually quite a few biopolymers that are part of the plant cell wall one of them shown in orange here is cellulose So this is what's really exciting about second generation biofuels These cellulose Fiberals are the polysaccharides which which with which we're trying to extract sugars to generate liquid biofuels But as you can see these cellulose fiberals are tied up in a mat of other bio polymers including lignin So in this context lignin can be a nuisance because you need to get rid of it to get at cellulose So as part of biofuels processing streams Where cellulose is coming out at one end to get fermentable sugars? There's also a large fraction of lignin. That's very low value. That's generated So to take a closer look and compare cellulose and lignin again cellulose is a polysaccharide So we try to get out these monomers so that we can put them to work with microbes to generate liquid biofuels Lignin looks very different And what really attracted me to lignin was the fact that it's one of the only sources in nature where you can get these Aromatic all-carbon based units And so I thought that this is currently a very low-value material But perhaps we could work with it to and apply some chemistry to make it into something more valuable And again cellulose is the most abundant biopolymer earth, but lignin is just the runner up So there's an order of billion tons biosynthesized annually So in thinking about this problem in my lab We've been approaching it in two different ways. This is kind of a busy slide, but but let me walk you through So again, this is just a model of what lignin looks like from plants One approach to using lignin would be to actually break it down and try to capture some of these valuable aromatics out of lignin You could see very quickly you start to to get towards compounds that look like BTX like chemicals So this indeed could be a renewable source of platform chemicals However, this is a difficult thing to do even in nature. It's hard to break down lignin And to do it in a selective way is quite a challenge So a second approach that we've taken in parallel is rather than break down lignin. Let's use it as it is Let's use it and see if we can generate novel materials and biocomposites from it However, it turns out that lignin really functions best when it's part of that fabric in the plant cell wall So by itself it doesn't make a great material So what we've tried to do is combine lignin with other renewable Polymers sourced from nature to make novel composites and simply mixing them together as I'll tell you Also is not ideal. So surface modification of the lignin and actual physical cross-linking of lignin with other bio polymers Is what we've turned to to generate lignin building blocks with tunable properties So you probably can tell I like to think in terms of molecular structures So on this slide, I just I like to take a step back and think about what's available from nature in terms of biopolymers There's quite a bit of diversity, but there still are some limits to it So there's kind of a repertoire of biopolymers some you may have heard some you may not have of course DNA is is a very Widely-noon biopolymer polysaccharides. This is an example of chitin Biopolymers, but there's also some nice poly esters and even hydrocarbons rubber poly isoprene So what we wanted to do is take lignin and see if we could combine it with one of these other Renewable biopolymers to make a composite that was high performing And so what we thought is we have hydroxyl groups here on lignin Perhaps we can find a way to chemically link it to a polyester So I've shown here polyhydroxybutyrate, but another renewable polymer that you can get from natural materials is poly lactic acid And that's the one that we focused on So I also want to mention that Lignin comes in many different forms Depending on how you get lignin out of the plant if you're trying to make paper You might use a certain process that that ends up giving you lignin with Certain chemical functionality if you're trying to extract sugars to make biofuels You might get another kind of lignin So the one that we focused on is this Injulin AT lignin which comes from the paper and pulp industry But ultimately our goal is to use lignin that comes from biofuels processing streams since we anticipate With second-generation biofuels a lot of this will be available Okay So again the challenge here is to take lignin and see if we can combine it with some of these poly esters To make a renewable material and I'm going to make a long story short by just showing you the the final results here That came through that collaboration with multiple faculty in chemistry structural engineering and chemical engineering What we ended up doing was taking lignin and actually graft polymerization of Lactide to generate a lignin poly lactic acid Co-polymer so we were able to show using a variety of spectroscopic techniques that we had a covalent linkage here between the poly ester and Lignin and the way we did this was to use a green process So Bob Weymouth in chemistry had some very nice catalysis that we could apply to make these kinds of renewable co-polymers these co-polymers turn out to blend very nicely with poly lactic acid to generate biocomposites So just to give you a sense of the importance of actually linking lignin covalently to the poly ester This is what happens. So here's poly lactic acid by itself. You actually can't see it. It's translucent And it's poly lactic acid is an important material for making things like biodegradable cups and renewable food containers So if you mix poly lactic acid directly with lignin you see that you get a composite But it's it's not the lignin is not well dispersed within the poly lactic acid matrix However, if you mix poly lactic acid with our covalently modified lignin we now get a much improved dispersion In these PLA composites And so you don't have to just look by eye To see that there's the blending is much better here the UV and optical properties change as well So this is just a profile showing UV transmittance. This is actually a problem with poly lactic acid plastics that are used In that that there's quite a bit of optical transmittance at higher wavelengths But you can see when you compare this green line here to the red line when we use our co-polymer We get very nice absorption on par with what you observe with Polytothalic acid compared to the red line, which is just mixing of PLA and lignin together So mechanical properties are also Withheld here as well these green bars. These are just different mechanical tests performed by my colleague Sarah Billington and her students to show that when once you start adding this co-polymer Of lignin PLA to a PLA matrix you retain the strength of the material So one drawback here though is that we're taking lignin We're covalently modifying the PLA and then we're mixing it with PLA So the total amount of lignin in these materials is not very high So another approach that we've tried to take here is to make the material The much higher percentage of the material lignin So this would be a much better use of our lignin source and through chemical modification We thought we might be able to generate a renewable base adhesive Right, so what we've done here again I won't show you the details of the chemistry But we've been able to take lignin and use a renewable biobase cross linker to generate Again a covalently modified lignin which now has adhesive properties So you can see these are some sandwich boards made in the Billington lab I mean we envision that this kind of co-polymer could be very useful as a renewable adhesive So again just illustrating some of the mechanical properties of this biobase adhesive This is done with a three-point bending test To show that lignin adhesives actually retain very good strength In this context compared to other biobase adhesives on the market So to take a step back I think we've done some nice work with lignin And we think that there's a lot more to do here But in general again we're really interested in renewable materials And one thing that we're constantly up against is that some of the polymers in nature Don't have the kinds of properties that we might want for a plastic or a packaging material And so where do we go if this is our repertoire of biopolymers what can we do from here So one thing that we've started thinking about is that Even though this is the repertoire of biopolymers found in nature There's a much larger repertoire of monomers That are renewable found in nature And so we could use these monomers and then apply either a chemical or an enzymatic polymerization process To make a non-natural polymer that perhaps has materials properties that are more desirable So I think this is kind of what's on the horizon for us in terms of green team efforts So in order to in order to obtain some of these monomers A lot of what's required is metabolic engineering of pathways in nature So I want to take the just the last few minutes here and tell you a little bit about How we think about building metabolic pathways I mean in that context I'm going to turn back to this molecule That I told you is very important for human health atop a side This is currently prepared semi-synthetically So the the the part in black here is isolated from the plant And then chemistry is used to build on this functionality of oxygen So we would like to know how does nature make this molecule And can we engineer that pathway so that we can make other derivatives On this compound with improved properties such as side building activity So again these are small molecules coming from plants The one that I'm going to highlight here is a clinically used drug But this kind of process could be used for making any kind of molecule That could potentially come from plants Something important for nutrition biofuels materials and fine chemicals So what do we need what do we need from plants To get to the chemistry that's involved in making these molecules Really the key is the blueprint So the biosynthetic genes that encode the enzyme catalyst that make these molecules And since 2000 when the first plant was sequenced We now have about a hundred plants Who have we have some genetic information about their genome sequence So just with these letters on a page we can start building pathways To make these small molecules So turning back to that compound I told you about a top aside This is our test case here We would like to be able to metabolically engineer this pathway And as I told you it starts out from a molecule that's pretty simple It's actually the precursor both to this molecule as well as lignin But the entire biosynthetic pathway is not known So there's a fraction of it that we understand well So I'm just summarizing here which is sort of the bottom left portion We know the genes and the biosynthetic enzymes that are involved in making this advanced stage Intermediate but there's a big portion that we don't know So it's really impossible for us to actually go and metabolically engineer the entire pathway at the moment So this is the challenge that my lab took We wanted to take gene information that we had from the producing plant We don't want to work in the producing plant We want to be able to metabolically engineer the entire pathway And so we had again a part that was known and a part where discovery was required So how do we go about discovering pieces of a pathway and components of a pathway that are not known So like I said, we don't want to have to work in in the actual plant We'd like to be able to take these biosynthetic genes and move them to some other host where it's much easier to observe activity And it turns out that an easy host for us to use is the tobacco plant in lab So we can take biosynthetic genes one two three four any number of them And within just a matter of days we can put them into the leaf of this plant And we can start installing a pathway We then use mass spectrometry to observe new compounds that that are produced So in this way we can combinatorially start building a pathway and discovering new pieces So again our first um Going back one side Our first objective here was to build the known part of the pathway and then we wanted to discover the back part So I'll just tell you where we're at in that process Um and show you a little bit of data Okay, so I'll just close by um acknowledging my research group. I have five graduate students who are working on these projects Um, uh, as well as several undergraduates and a postdoc I mentioned our collaboration on the renewable materials efforts As well as these are some funding sources and I'd be happy to take any questions you might have Yes, sorry the Thank you. Can you comment anything about the phase diagrams of these bio polymeric systems? The phase diagrams. Yeah. So like you mentioned like, okay, um for storage Um, we know that we use binary colloids to develop New systems. And so there's a phase diagram of Normal polymers or regular polymers. So I was wondering if is there a specific phase diagram for biopolymers And can you comment anything on? How does that look different from regular polymers so, um Not really actually. I'm not I'm not sure I understand the question in terms of of the material itself compared to Um, other polymers found in nature or other man-made polymers Other man-made polymers Well, I think I showed the the properties that I'm most familiar with are the ones that we've measured for The lingon pl a copolymer and that was the optical properties um, and then the mechanical properties so Uh beyond that, I guess I don't I don't have any other information But again, you know, one of the nice things about working on this project is my Um expertise is really in the area of plant chemistry Whereas, uh, I rely on the billington lab for mechanical engineering expertise Um and curt for polymer chemistry curt. Do you have any comments that you you could add on that? Okay So, um, sorry Yes Trisa wegaser from chevron, um Out of curiosity, why did you pick the tobacco plant as your model or your host? Yeah, um, so tobacco works the The method for actually expressing these biosynthetic genes in tobacco is not ours. That was established in the literature Um tobacco works really well what we have to do and I skipped over this But to get a gene into a leaf we actually have to infiltrate this bacterial suspension Tobacco has really nice big leaves. Um, and also has a reasonably short life cycle Um, so it's been a nice model plant to use in the lab Sorry, once you put the gene into the leaf, can you pollinate it and all its children have got the same ability? Um, so that's that's the the approach that we're using that I really like is that this is transient expression We're not generating Transient or or transgenic lines of plants. So we're only Introducing DNA into the leaf not into the seed. So it's it's progeny will not carry these biosynthetic genes And that's why we can do it so fast You know, it only takes a few days to see results