Anaerobic Microbiomes and their Applications

Anaerobic Microbiomes and their Applications

Ponente:
Dr. Christian Abendroth

Yeah E on okay take okay e e and [Applause] ch for for Thank you Um Prof PR Para te Christian avend professor is Po in instit the waste management and circular economy in Inen say in in in Valencia For for ch question okay thank you very much for this uh introduction can you all hear me everything’s working okay so I will stay here oh thank you yeah so I also speak some words Spanish but uh more like a child so I think you uh would maybe not

Understand my talk when I give it in Spanish so I will better give it in English I hope you all uh speak some English or at least can understand it if you have some questions you can also try to raise these questions in Spanish I can try to understand it and of course

Then I will answer in in English so thank you very much for this uh introduction I also have some introductory pictures that I will show you so that you can see where I’m coming from um this is the Institute where I start started my research it’s in yenna not in

Vienna many people understand Vienna but Vienna is in Austria and yenna is a small city um in the center of Germany and here we have this institute the Robert boil Institute is a private Institute which is working almost exclus exclusively on anerobic digestion and also in a very close collaboration with the industry

So when I started here I actually started already doing my master thesis there and I knew that I wanted to go somewhere abroad to do my PhD and in the end I decided to go to the university of Valencia in Spain and it was a difficult decision because I had

No no funding ready so I decided to apply for some research money doing my master thesis and I was very lucky that this was working um in the end we got funding for an industrial project and we were uh working in collaboration with the University of Valencia on this so I was traveling

Every three months from yena Germany to the University of Valencia and then three months later I traveled back and I did this uh for four years so I was pending for four years between the University of Valencia and the Robert boy Institute in yena so those are directors that we are

Actually or that were constructing when I was still there at the Robert boy Institute I was rather responsible for the biological part but I was always in very close collaboration with Engineers which were building these kind of reactors where were uh testing different conditions to investigate the digestability of certain substrates or

To anal Anze how we can improve anerobic digestion processes this is the institute in Valencia where I studied for almost four years um they are really focused on molecular biology bioinformatics they work a lot of um with sequencing DNA sequencing microbiology so it really goes into the

Direction of biosciences and I have to say that from my background originally I am also um um bioscientist so I studied biochemistry and then my thesis in Valencia was in biotechnology and then eventually after my thesis I did my postdoc thesis at The Institute for circular economy in the

University of Dron in this time I was still collaborating with my colleagues in Spain and my colleagues at the Robert boil Institute until I F finally um came to the University of cus where I’m now hired as a professor since two years so I’m relatively new I’m still struggling to

Get all my lecture material together and survive all the lectures but so far everything worked out so I marked you here some important places so this is the center of Germany uh we call it turingia and here we have the city of yena that’s where I’m still living and where I did

My PhD here we have the University of Dron where I did my post and here we have cotus the University of cotus and here you see a little bit larger picture of the University of cotus or not the university but the the place where it is

Located and you see that there are like two places one is in cotus and the other one is in zenenberg so originally those were two universities and now they have been combined to one larger University which is now the university uh cotus sber yeah to close this introduction I

Present you here a nice view on the University of cotus here in the background you see see the campus of the university and then here in the front you see the library so the university is quite proud of this Library which looks a little bit like a spaceship so it’s a

Really nice place to study um I searched for some information to give you a little bit of insight into what’s happening at the B cotus so it’s a small University um compared to other universities in Germany we have roughly 6,00 ,800 students and many of them are international students this might be

Interesting for you if you’re planning to come one day to make your PhD here or just for a short stay we actually have one uh person here who visited me in cotus uh Mitzy Lopez was here for or there for three months and if you have any interest in this you can talk

Directly to her and get some Firth handed insight how studying at BTU works yeah we have six faculties and we have 60 study programs in Bachelor and master so I’m from faculty 2 which is from environmental sciences and I’m actually the study leader for environmental engineering so a field

Where you probably feel more comfortable but we also have faculties which work on mathematics and uh informational Technologies we have faculty three which is on the construction of machines and electr techniques faculty four is on uh Sciences for human human science faculty five is about economy right and

Society and then finally we have faculty six which is about architecture and construction of buildings there are three main fields which we are focused on at a B cotus so we are interested in uh energy and decarbonization we interested in health science and life sciences and we are

Interested in global changes and all this is connected via artificial intelligence research so those are the three basic Columns of the research at the btu at the moment we have 180 professors and I think it’s a nice ratio compared to the 6,400 students or 6,800 students so um usually every Professor

Has another employee to get some support with teaching so we have something between 350 and 40 people that can actually teach and if you make the calculations then you have yeah less than 20 people per person if you just make an average number and I think this

Is nice because this results in a really close uh collaboration or um connection between the professors and the students which is really nice for teaching yeah and since two years now I’m leader of the chair for circular economy and I’m somewhere in between of bioengineering and biosciences I told

You in the beginning I’m originally from from my studies a bioscientist but now I’m actually trying to teach bioengineers at the B cotus to give them some idea of biology which is also important for engineering especially if we talk about anerobic digestion so here you see several reaction systems that we constructed at

My chair so this is until some point bioengineering but then we’re really interested to understand what’s going in in uh uh what’s going on in inside these reactors so here’s one picture um that we did with an electron microscope just to see um what’s happening inside of

Course just from such a picture we don’t really know who is there what are the names of these microbes here we need some other Technologies which I will also introduce to you in the further course of this um module this is our logo now because when I started my chair um many people

Contacted me for emission trading or mass flow analysis and many topics which are concerned to Circular economy but uh with this logo I wanted to high of circular economy therefore we have here this circular symbol with some microbes inside FG is a abbreviation in in German for chair and KRW stands for

Circular economy it’s also German abbreviation and then below we have circular microbiomes to highlight that we are really interested to understand how microbiomes are involved in circular economy and how we could uh use them to make the circular economy more around let’s say yeah so far we have some uh main topics

We are working on we have multiphase fermentation and um multi-stage digestion I’m not going to explain this reactor now in detail we’ll talk later about technological approaches here then we are working on power to gas anyone knows what power to gas is have you heard about power to Glass before

Okay so uh it’s something which is uh I would say quite hot in Germany at the moment um because sometimes we produce too much electricity and then we don’t know what to do with it and it’s really difficult to save this energy and one idea is to

Do this with power to gas so we can perform an electrolysis and when we electrolyze water with this Surplus energy we produce hydrogen and oxygen but then we don’t know what to do with the hydrogen because it’s difficult to store um it has a large volume compared to methan and when we

Produce a large amount of hydrogen at once we can’t directly use all of it so we have to store somehow the the hydrogen and the idea is that we are feeding microbes with this hydrogen and so-called methanogenic are here you will learn at a further course what Asia are so-called metan genic Asia

Are able to eat hydrogen and to use it to chemically reduce carbon dioxide and like this we can produce methan which is much easier to store we can directly pump it into the German gas grid which is much better with methan than with hydrogen so the gasd was originally produced for for

Methan we can also store it much easier because the molecule is much smaller than methan so uh if we have like a foil tank for for gas then it’s much easier to store methan than than hydrogen yeah this is actually um I would say at a doorstep to the industry

So we have a patent here in the University of cotus and this patent is licensed to a company which is trying to bring this now to the market and there are a few other companies which are competitors on this topic and they now try to get rid of other competitors

Let’s say and to stabilize their position in the market and uh at the moment we are applying for first project to test this on an industrial level so I would say the basic science is ready here and now the question is how to make the the transfer into um into the industrial

Level can you see everything do I block the side or is it okay yeah okay yeah then we have teaching of course and here I’m visiting some um yeah this is a compost but there is also a land film and this work with our International course for environmental

Resource management for them it was really interesting because many of them are from developing countries which are not with proper landfills at the moment and for them it was really nice to see how a proper landfill can work how you can make sure that nothing is leeching

Out into the soil that no gas is coming out that you can collect all the gas to uh produce electricity from it so um that’s what we try to to show them and they have directly a composting plant here next to the landfill side and then of course anerobic

Microbiomes so we are really interested to understand what’s happening inside of these reactors or inside of these typical anerobic digestors or what’s happening in a composter with composting we are just getting started so far I was only working with anerobic digestion but we just got a student from Afghanistan son

Who gets now funding for four years to work on microbiomes in uh composting so I’m very excited to see what’s coming out of this yeah and we also tried to make some advertisement here at the moment we are engaged in a huge European project with 14 Partners all over Europe and all

Together we want to highlight the word microbiomes in anerobic digestion because at the moment anerobic digestors are basically a topic of environmental engineering and most of these Engineers are concerned about the technical construction of these plants but they are not really so Keen to look deeply inside these reactors to see what’s

Happening on a microbial level and what could be done done to to improve these digesters okay that’s all with my introduction I hope it’s all clear and now we can start with the real presentation or the real course uh I don’t know whether there are any questions so far feel free to speak

Um you don’t have to raise your hands necessarily you can just speak into the room if there is something you want to ask okay but you’re nodding so everything seems to be fine okay so um yeah I guess you have seen this list already those are the

Topics that I would like to talk about in the next two weeks um I saw already that I planned for a bit too much time so I have to restrict myself a little bit I don’t know yet how to do this either we cross out one topic entirely

Or I’m shortening some of the topics I have to see how I’m doing this so I have a basic structure written now but um the fin polishing is still to be done so I will provide you with each lecture after I gave the lecture to you so you will

Get this lecture then I guess by tomorrow yeah we will start with some Basics because as I told you usually I um teach a similar lesson to environmental engineers and usually there are not much concerned with topics on biology so for them it was uh really

Helpful in the past two years years that I gave them just a very rough introduction into biology itself into the functioning of cells how organisms work and then we go a little bit into photosynthesis maybe you had it already in school um I remember it from school

But when I asked my students about it no one remembered let’s see whether you remember anything and and then we will talk about microbiomes I will introduce the term microbiomes and then we will actually talk about some technical Concepts I don’t know had you already um some insight into biogas plans did you

Cover this topic in your lectures so far is it completely new to you or little bit bit so you have a rough idea what this is about okay great yeah so we will go a bit deeper into the technical concept here and then we will talk also a little bit about

Biochemistry of anerobic digestion um of course you could fill a whole course just with biochemistry and I’m not going to do this so I really give you a short summary of things that are important to understand what’s happen happening in anerobic digestors well and once we covered this basic information then we’re actually

Coming to the things that I work on I included also my personal research from my PhD when it comes to taxonomic profiles in my PhD I was collecting a lot of of different biogas plants and then I was extracting the DNA sequencing everything and then I was comparing the taxonomic profiles with um

The chemical parameters that we had in these plants so I will give you an insight into this then we will also talk a bit about proteomics maybe you have he about proteomics it’s about the proteins that we have in anerobic digestors which are really important to understand the functioning of anerobic microbiomes

Because on the on the taxonomic level we basically get an insight about who is there but we are not entirely sure what what they are doing and with proteomics we can get some insight into what the microbes are actually doing there and then uh the last chapter um it’s

Something that I definitely want to cover so I have to shorten these lectures in a way that we manag this because this also includes the results from my postdoc thesis where I made an overview on interesting microorganisms that we could use in the future and in future research to improve anerobic

Digestors and then a very uh new topic from the point of basic research is the application of light so usually there is no light applied in anerobic digestion um so some people also talk about dark fermentation and this term already says that there is no light

Involved but I think it could be really promising to apply light here of course it’s a really far way to go from an understanding that light has an impact here to the Industrial Level so this is very deep basic research yet but I think it’s also interesting to for you to see

What’s maybe coming in the in the next years okay so much for the overview of the whole module and now we start with the introduction from the content line so so I will talk a little bit about biochemical conversion I will also talk about the structure of a cell and then

We will introduce the main players of anerobic digestion processes which are mainly bacteria AA and ukar are you familiar with these terms yes yes okay great I will still repeat it because I included it already in my lecture but so it’s nice that you already have some

Ideas about it and then we will close with a general view into the biomass cycle before we start the next topic I don’t know how fast we’re going with this maybe we can start the second topic today let’s see okay any questions so far okay everyone’s happy

Great okay so what we are seeing here this is actually the total biological waste that we have in Germany it’s 15 million tons sounds like a lot uh if we take into account the total waste not just biow waste we have maybe 400 million tons of waste approximately

So it’s really just a small fraction and we are not even able to collect all of it maybe you have um I don’t know how it’s handled here um but in Germany we try to retrieve the bowte separately this works more or less fine not all

Cities are doing it already some try to get around it there are some small villages and they say yeah well most people do composting so we we just uh don’t collect it separately and so step by step we try to evolve here and the idea is that eventually we are able to

Collect all the bowte separately why should we do this what’s the importance of this any ideas what’s the advantage of having the biological raised separately from the total rais yes please easy manage have seate yeah comp so you mean that the further treatment is easier but the separate fractions yes this would be

True it’s some additionally effort though so to get it separated you really have to M motivate all the people to participate in this but then once you have it separate um then you can treat it much easier any other ideas why this could be helpful yes please compost composting yes

Composting composting is really helpful we can produce fertilizer with it so we have actually a product out of it and well if you don’t collect the biological way separately it would basically yeah basically go into a landfill so we came use the race somehow and there are several

Possibilities to use the race so we can uh produce compost as you suggested or we can perform anerobic digestion and the big Advantage uh in regard to anerobic digestion is that we are also producing electricity and when we perform composting um all the energy dissipates

In form of heat so we basically lose all the energy and if we are now performing anerobic digestion we have the possibility to collect um the biogas which we can incinerate and with this we can then produce electricity so um in the end it’s much more friendly for the university for the

Um for the environment and we are relying Less on fossil fuels which is also an overall goal for for the industry yeah as I said we have 50 million tons it’s a small fraction of the waste and so far most of it is used for composting so it would be nice if we

Put all of in all of it into a biogas plant and I think it would be feasible because from a biogas plant we also get fertilizer we basically digest everything which is carbon and then we have a concentrate rich in ammonia and phosphate and this is a really nice

Fertilizer maybe it’s not as good as compost but it’s still a good fertilizer and we have Additionally the the electricity and then we have a large fraction of biowaste which is not presented here in this organic fraction which is the residual waste so we have a

Waste bin for the organic waste and then we have a waste bin for the residual waste and well not everyone performs the Sorting so organized some people just throw it into the residual waste sometimes you can’t separate it sometimes you have for example um some kind of container which

Still biomass inside and you don’t want to open it and separate it so you just throw everything into the residual waist and in the end we have a certain fraction of bowte in the residual fraction I don’t know how high it is but we are trying now to also develop

Specialized systems which are able to um industri sort this residual waste to gain an organic fraction that we can then throw into our biogas plant and that’s the topic of my main interest how to do this how to take all these residues and convert them in something useful and in the further

Course of this uh module you will see that we are not only talking about electricity so far electricity is the main interest of people that are performing anerobic digestion but in research there are already thousands of article where people highlight the possibility to produce other things that are also important for the

Industry especially organic aets organic assets are really expensive and valuable for the chemical fine Industries and then also High hydrogen it’s also possible to produce hydrogen on a biological level oh now we lost our presentation someone knows what’s happening oh it’s back perfect well and this brings us already to

Biochemistry what has bioch CH istry to do with all of this the most simple answer which is maybe not 100% correct but it’s very general uh we can say that we have a substance a and we want to produce a substance B and for this we need an

Organism and when we know how this organism works and why this organism is there or why it disappears which other microorganisms are involved if we understand this that then we might find a way to improve the transition from our waste which I call substance a to something useful which

Can be many things not just methan and compost so we can Define that biochemistry is the study of chemical processes in living organisms or the study of the metabolism we have a big problem here because it’s not so easy to eat waste not for us and also not for the

Microorganisms we could imagine that the microorganisms like the waste much more than we do but this is not always the case there are some substances which also the microorganisms cannot digest and this is where we have an interplay between biochemistry and biosciences and engineering to to find a way to treat

Pre-treat these substances in such a way that our microorganisms suddenly like these substances and start to ferment them to produce something useful out of it so sometimes biology needs help and here are some terms which you certainly know uh like biotechnology biochemical conversion bio Refinery bioeconomy those are terms which are deeply investigated

At the moment so you can already find hundreds of articles about it and I will focus not too much on the technical level I know that’s uh what you probably would like to hear most but I think it’s really good to get a small taste of biochemistry as an

Environmental engineer as well and I would promise to make it as simple as possible so that you can follow it even without any pre- knowledge on biology so the focus is on biochemistry molecular biology and microbiology but always in regard to environmental engineering and here we will start with

A simple question what is a procario anyone knows what a procario is no not an animal cell hello oh yeah we hear you uh is a cell without nucleus yes mostly true there are some exceptions but that’s the definition that we usually apply so it’s quite correct

So we can say it’s a space separated from the environment and in this space we want to fill in our waste and we want to retrieve our product out of it this bace is surrounded by something that we call membranes probably you have he of membranes we have um specific kind of

Molecules which are hydrophilic on one side and hydrophobic on the other side and then they attach to each other because if they are in water then all the hydrophobic uh ends are attaching together to avoid the water so in the end you have two hydrophilic sides and the hydrophobic part is in

Between and this makes it really difficult for any substrate to penetrate through this membrane into this space where we want to create our subst substance of Interest there’s a transport so these organisms are able to specifically take up certain substances like aquaporin it’s a channel just for water we also

Have diffusion but this works just for very few um substances for example some specific gases with channels for irons here it says gated iron Channel because it’s really specific for certain ions which are in the right size to pass through this channel we have sort because sometimes

It could be that one substance can’t enter because there’s already so much inside so there’s like an osmotic gradient and the substance would rather go out but this can be circumvented if you have an code transport from another material which is not present inside but present outside and then this material

Can kind of create the necessary uh kinetic energy to move this other substance into our space we have carrier molecules which can take up a substance which is of interest for us and they can pass the membrane and then release the substance there or we have antiporters which is

Just the opposite of an sorter so you see this is already quite complex and I promise I will not talk much more about any transport mechanisms in cells in the whole course um but you get an basic idea how this Transportation works here we have a cell

Wall I guess you have all heard about cell walls in which organisms do we have cell walls any ideas plants and bacterias that’s right so plants have always a cell rall and BAC we are usually all also and then we also have funji okay so those are the basic cells

That we know which have a cell wall that’s a cell wall it sounds quite complicated again I promise I’m not going very deeply into this because it will not help us much um for the further course of this module I will just for the completeness mention that this

Exists here you see so-called grum positive bacteria and grum negative bacteria maybe you have heard of this grum negative and gram positive it’s um just based on a certain coloring substance we can put it on the microbes and either they are colorful than they are gr positive bacteria or they don’t

React than they gr negative bacteria it’s just one way to to Cluster all of this um I’ve seen that you have made a photo um it’s not necessary I mean you can do it but I will provide the the lecture eventually so you will all all get it

Um yeah and then here we have the fungi the plant cell is missing here so this was just one figure that I have found and yeah usually when someone looks at this without ever thinking about a cell wall before he’s quite confused or might be quite confused from all these words

But actually they are not that complicated I I will just explain few of them for example the tonic acids tonic acid sounds really complicated and probably it’s difficult to remember the NM the term tonic but taas comes from the Greek word wall so you can say it’s

Basically an AET which is in the wall of organisms sounds pretty simple in the end or we have Pepto glycan maybe you have heard of Pepto glycan before they are also known as murin also a strange term again but then if you translate the world the word murus it

Stands for wall again so another wall substance that we have in our walls um yeah and the pipan is a combination of peptides and polysacharides so glycon is A polysacharide and P peptides is usually a combination uh of a maximum of eight amino acids and if you have more than

Eight amino acids connected then you already have a protein so we have some kind of acids in these walls we have uh pides we have peptides we have also substances which are pure purely um carbohydrates um polysaccharides like the glucan it’s very very similar to the glucose and actually it’s just a polymer

Made out of many glucose um um molecules then we have the chitin I think you all have he about the chitin where do we find a chitin yeah fungus right so that’s all so I’m I’m not going deeper into this why is this important for us I think it’s just important to

Know that we have uh relatively complex polymers which are sometimes inside and on one hand they help the cells in order to have a specific transport to have a individual Behavior to interact in a really individual way with other microorganisms also for communication and so on therefore we have so

Complicated and uh organism specific cell walls and membranes but then for us it’s really important that some of these polymers which are implemented into these walls are really difficult to degrade so like Cheatin for example or lightning you all know line from plants so if you put line into a biogas plant

There will very likely nothing happen or very little so you get very little biogas out of Timber or wood so this is again a point where we come to environmental engineering so we need technologies to somehow Crush these molecules to make them small and accessible for the microbes

Involved okay now we know what’s surrounding our procaryote but then there’s something inside for example the DNA I guess you all know DNA and yeah the DNA is the basic information storage from um all life not only procaryotes but all life that exists um uses DNA to carry information and usually this information

Is so specific that we can uh distinguish different organisms just by reading their DNA then we have RNA anyone remembers what RNA was I can give you the full name which is yeah it’s an nucle acid yes what is it good for one what of one chain single stranded yes right what

Else why do we need it is the D not enough yes please yeah that’s right perfect so uh there’s a process called transcription this is when the is reading the DNA and then it tries to translate the DNA into RNA and the RNA can then be used to produce the proteins

But RNA can more so this is the the basic um School knowledge that we use these rnas to produce proteins but then uh if we go into research we find strange articles like this one where we have an RNA which a really strange structure and this is a like a motor

Unit for a packaging system inside the cell so sometimes we have quite unusual um behavior for the RNA but mostly the cell is using it to translate information from the DNA into uh proteins that can be used by the cell or implemented in the structure of the

Cell then we have the ribosomes what are the ribosomes for four there are a macromolecular complex of proteins and RNA yeah that’s right and what do they do and uh this uh for synthesis of proteins yeah that’s right perfect so the RNA these small um stripes are our

RNA and they go into the ribosome and then for each triplicate for each combination of three nucleotides one amino acid is chosen and attached to the growing protein chain from the ribosome so with this we have already the complete picture uh of biochemistry I would say here you see

The overall structure of the ribosome and as you said the the ribosome also consists of RNA which is quite strange because it appears that the RNA is able to read other RNA and to synthesize something out of it so I think this is quite surprising and this brings us now to the

Basic dogma of molecular biology from DNA to RNA to the protein so DNA is our informational storage RNA is the information what the cell wants to do in this very moment to translate this DNA and then the protein is the outcome from the uh RNA after it passes the ribosome

S so why is this important we will come back to this quite often because this is the basic for some uh analysis techniques that we need to understand what’s happening inside an anerobic microbiome yeah what rare proteins again I mentioned it already so maybe someone remembers yes than eight Amino yes that’s right

Perfect so eight amino acids is one peptide and several peptides can form one protein or when the peptide grows longer then we also get a protein yeah here I explain it again but we just talked about it this is just for you when I provide later on the the file

For you and here you see the chemical structure of an amino acid so you have basically an amino group then you have this carboxy group and then in the middle you have one carbon atom which is connected to a residual um substance which makes the amino acid specific so we have kind of

20 different residues which results then in 20 different amino acids that we can use to uh code our protein let’s say here you see all of them um don’t be worried you don’t have to learn them in our biochemistry studies I had to learn all of them and I forgot all of them

Again so I don’t want to give this task to you but it’s just for you to see what are these amino acids are and later on we will also talk a little bit more about their functionality if we find the time so at this point I have a very

Short video to summarize um the dogma of molecular biology but for an eukariotic cell I hope it works and also that the Sound Works let’s try here is a cell the basic unit of all living tissue in most human cells there is a structure called a nucleus the nucleus contains the

Genome in humans The genome is split between 23 pairs of chromosomes each chromosome contains a long strand of DNA tightly packaged around proteins called histones within the DNA are sections called genes these genes contain the instructions for making proteins when a gene is switched on an enzyme called RNA polymerase attaches to

The start of the gene it moves along the DNA making a strand of messenger RNA out of free bases in the nucleus the DNA code determines the order in which the free bases are added to the messenger RNA this process is called transcription before the messenger RNA

Can be used as a template for the production of proteins it needs to be processed this involves removing and adding sections of RNA the messenger RNA then moves out of the nucleus into the cytoplasm protein factories in the cytoplasm called ribosomes bind to the messenger RNA the ribosome reads the code in the

Messenger RNA to produce a chain made up of amino acids there are 20 different types of amino acid Transfer RNA MO ules carry the amino acids to the ribosome the messenger RNA is read three bases at a time as each triplet is red a transfer RNA delivers the corresponding amino

Acid this is added to a growing chain of amino acids once the last amino acid has been added the chain folds into a complex 3D shape to form the protein okay that’s it um I think it was a good summary of what we have heard so far there’s just one

Thing that we didn’t talk about so far which is the nucleus and the nucleus was specific for what again where do we find the nucleus and which kind of organisms I think you mentioned it before ukots yes that’s that’s correct so to our original question what

Was a procaryote again we can say it’s B basically bacteria and ARA which have this simplified cell structure without a nucleus and then we have the ukar which are people but also animals plants and fungi at this point I would like to highlight that there’s a huge difference

Between bacteria and AIA and many people forget this so um very often when I talk to people about biogas they say there are metog genic bacteria and something like this does not exist there is an exception but um it’s not really that relevant for biogas production so usually the methan uh

Itself is produced by so-called AIA which is an own domain of Life next to the bacteria they both look this way but then if you go on the molecular level they are really different and sometimes these areia are even closer to the UK carots than to the bacteria therefore it’s really important

To distinguish between bacteria and Asia when it comes to biogas production here are some uh differences I’m not going to discuss them in detail just to give you an idea what the difference is so we we can’t say there is an overall function which makes AIA specific they can do very similar things

Like the um bacteria but then if we go really deep into the biochemical level we see for example that uh ukar have no circular chromosomes but Asia and bacteria have or only Asia have a membrane with branched hydrocarbonates or only bacteria have a cell wall with peptido glycon so it’s really on the

Biochemical level where we have this differences um there’s maybe one thing where we can generalize very often AIA are extremophilic so very often they are able to survive in strange environments with a lot of salt or really high temperatures or they can produce the methan which is at the bottom of the

Energetic feasibility for for life in general also refin very specific membranes for the ARA and um they have some very specific chemical structures and one interesting thing is that sometimes this um B layer for the membrane is just connected in the middle so we have

Like a monol layer in the end and this can make the whole cell much more stable and because of this they can for example Thrive at a BL like smokers in the in the deep sea where we have really harsh conditions where other organisms can hardly

Survive there is this tree of life maybe you have he about the tree of life it’s something that we build on the similarity of organisms we have the beginning with Luca maybe you have heard about Luca Luca stands for um last Universal common ancestor and since then outgoing from

This cell based on the theory of evolution the rest of Life evolved and very early um around 3.5 billion years ago we have already a big br Branch between Aria and bacteria then everything is branching further and further but you see that from the Aria the UK cariot are

Branching out and that’s why the ukots sometimes are closer to Asia than bacteria and sometimes is the other way around therefore it’s really important to distinguish Asia from bacteria and ukar all um ukar although they look under the microscope very similar to the bacteria so here we have now a eukariotic

Cell what would you say what kind of organism could this be to which organism could this cell belong a PL why no another idea it’s a animal cell yes that’s right so what would we need to make a plant cell out of this yeah that’s right something else that we discussed

Already cell it’s cell yeah that’s right so here you see the cell wall of plants again I don’t want to go really deep into the details here I just show it shortly but I think it’s important to understand the structure of a cell wall in order to know what to do to destroy

It to make it accessible for us so we have actually different levels here we have the plasma membrane then we have a primary primary cell Ro and then the so-called um middle Lamela again we have some very specific um molecules inside like the pectine for example um it’s also a

Polysaccharide or we have cellulose I guess you all are aware on cellulose here it becomes already difficult to degrade so cellulose is um not the best substrate for biogas plants but still sometimes we use microcrystalline cellulose for anerobic digestion experiments and this shows the importance of uh a targeted destruction

Of this materials once we have it in very small molecules then the organisms can swellow it and digest it but then when we have a complex fiber which is maybe even interl with lignine from from from trees then it’s really difficult to degrade this we have glycon it’s a another

Polymer mainly uh made from monosaccharides yeah those are the main components of our cell wall and this sounds very basic but I found a recent article that was really interesting uh from 2018 and they were investigating based on a chemical level crosslinking between hemicellulose and liin so they highlight

This here you see that there’s connection between both polymers here they also gave a chemical structure and this makes it really difficult to um to degrade this in anerobic digestion so if it would be just the cellulose we could probably somehow uh degraded but then we somehow have to um dissolve this chemical

Binding in order to separate the line from the from the cellulose to make it accessible for our biogas plants what’s actually the difference between lignine cellulose and hemos anyone knows this I think it’s a nice question because I ask this question very often and very often people don’t know it but

We use these terms very often I mean if I say liin everyone has somehow a picture in the head and has he this word somewhere same with cellulose or hemicellulose but then if I ask what is the difference people are often not sure about it do you have any idea yes

No yeah Sol is mean uh compo um construct with exos and Amic cellulose with pentos um molecular again please yes and the this solos uh is uh built with the um exos sugar CH of uh ex sugar sugar and the Yos is built with the pendos yes pendos sure not entirely but

There are different uh it’s a more heterogenous substance that’s right okay than great so so one nice answer already are there any other ideas okay then I will resolve the riddle you see here the legine and here the cellulose and here the hemicellulose what is the difference

Here what makes them so different I mean just watching them we see that they are different but um if we try to describe this somehow what makes them different no idea you have an answer you have an answer no uh is because the cellulose is bed on glucose gluc do you

Say yeah maybe this one answer so what is important is that the hemicellulose is Branched so here we have always one line and the connection is always the same so theoretically you could have one enzyme which destroys this connection and then you can already degrade it it’s really

Simple but then we have here the hemicellulose and if you have one enzyme which destructs this then you still have the branches the branches and they have a different binding so here you already need another enzyme this makes it difficult to to degrade it you need specified microorganisms or you can even buy

Enzymes and we have several companies in Germany which are selling enzymes to the biogas plants and then they throw the enzymes into the biogas plant to better degrade the hemicellulose yeah and then we have the ligin and ligin is pure chaos so there is no General accepted formula you can um

Watch different parts of Elin and you will have always a different formula it’s extremely heterogeneous you have always these aromatic groups inside which are really difficult to um to degrade and therefore liin is almost impossible to to be degraded under anerobic conditions but again here people try to develop special

Pre-treatment methods for example a so-called extruder and here we are um trying to destroy the line based on physical methods um until we have almost monomers let’s say so it’s really pulped and really small molecules which can then be accessed Easier by the mo microbes and like this liin also becomes degradable

There’s at the moment uh a discussion going on whether we should degrade line or not would you degrade line would you throw it into a biogas plant if you know that you could make biogas out of it based on this extruder for example would this make sense for you yes or no or

Maybe can you repeat the question please so if we have this extruder and this extruder allows us to pre-treat the liin to make it accessible for biogas plants would it make sense for you to use it as a substrate for biogas plant yes you say yes other

Opinions it’s like a sugar cane uh the plants with the me soup it’s like uh like timber forest like like wood from the forest or grass uhuh so it’s extremely solid and has a lot of line you said yeah yes why why did you say yes yeah yeah it’s one opinion other

Opinions so it’s uh it’s really a topic of discussion and and people find it difficult at least in my opinion to get a clear agreement on this uh I work together with a company that focuses on the degradation of wood they are from Finland they have a lot of wood

So they want to do something with it um but then um I’m not sure whether it’s a good idea because we can incinerate the the wood as well and if you have a really good incinerator plant then you can also produce electricity from this so you can collect all the heat you

Can uh create Steam and with this steam you can power a generator to produce electricity and this is much more efficient for for wood than a biogas plant because in a biogas plant if I’m lucky I can degrade 50 or 60% so I have like 40% of my substrate which leaves

The biogas plant again I need a lot of energy to steer it to move it through my biogas plant and in the end I just put it as compost in the soil so this is not that efficient but um yeah then there are other people who

Say that uh if we just incinerate that we are somehow losing the concept of circularity because we incinerate everything then we have the Ash and we also have the the the the fumes which might be toxic so it’s maybe not the best way and if we put it into a biogas

Plant we have at least a material use because then we still have a compost next to the electricity and according to the uh hery in in circularity we always want to have a material used before we produce electricity so electricity is the last option basically well it’s a

Question where we have no answer people are still offering it there are companies some incinerate some throw it into biogas plants and we need more arguments and more discussion about this topic to to fully resolve it so which time do we have okay we still half an

Hour yeah here I gave some information on what we just discussed just for later for you when you uh get the slides so we have done um further helpers for the biochemical conversion because usually we talk about bacteria and Asia if you read any research articles about microbiomes in biogas

Plant I would say 95% are talking about bacteria and AA just based on my stomach feeling I didn’t make any statistics on this but then there are other organisms which are also of Interest or they could be of interest in the future and we are still investigating this and there are a

Few articles now which indicate that protozoa meoa plant and algae they could also have some uh interest for anerobic digestion processes yeah what is a protozoan I guess you have he of what he of it before sometimes we call it primordial animals so those are animals that

We regard as very old animals and usually they just consist of um yeah a few hell so very often those are um micro organisms like the one that you see here yeah then we have the measur measur is then the opposite of a protur this is

An kind of animal where we have a lot of cells that are involved to build up this organism like these animals for example those are um protoo which are actually important for uh anerobic digestion processes maybe you have he of them before so any one of these guys um known to you

No they have actually a key function in wastewater treatment if you uh if you have a wastewater treatment plant usually have the the sludge activation and in the sludge activation you want to produce kind of uh granular flocks that can separate from the water after cleaning and usually this would not

Happen if we have bacteria and AIA they would grow everywhere and you would have um a thick solution like a thick sludge where you can’t separate anything but then you have these guys and they are actually growing on the bacteria in the sludge but sometimes you have bacteria

Which are able to grow in small granules and if if they do so then the UK iots the the protoo and mura are not able to to access them so they are eating all the free swimming bacteria AIA or the small cells and then we remain only with

The organisms that are fixed in this granules or this flocks that we can then separate from the water based on chemical processes like precipitation yeah those are complicated names and I don’t remember them either um maybe you could remember these names all of them are ciliates then you have

Some warms the warms are called nematodes or aneles and the rotifer those are more General names that you might remember um but I will certainly not ask in the in the exam about these complicated names here so I think now we have the basic rules

To to follow my module in the in the coming lessons and we have a basic understanding how these guys are working what bacteria and AIA are made of and how Proto metora and plants are functioning in regarding in regard to U carots and now we talk uh shortly about the biomass cycle

So this transfers all of this into a concept of circular economy so usually we have some biomass in agriculture we produce all kind of plants and we do something with it so we produce products and we use and consume these products eventually we can’t use them anymore or

We we ate them whatever uh and then we would like to still do something with it so we don’t want to throw everything on the landfill so we need certain concepts of recycling and reuse in order to get this into a circular concept again for example to use residues as fertilizer

For the production of plant material we can make this more and more complicated here’s just an example um we can even make it more complicated in this example we have here the the plants and we have a cow so we also produce biomass from animals then we have

Factories they process all of this to products that we can use and then we try to transform this into minerals that we can use into electricity or even heat that we can use so those are at the moment the best usage scenarios for for biomass I hope in the future it’s going

To be more complicated but that’s where we are now so what do we get from it in the end we have maybe new recyclables this is still part of research uh maybe slowly uh approaching already the industry then we have the energy fertilizer and the Heat and for the production we can

Distinguish between algae plants insects and animals which are important to grow some kind of biomass that we can use uh in the biob biobased Productions later on and in this module we will very much focus on this wet error and we will start from this right

Now here is a very short summary what we have here now so we talked about the basic structure of the cells which you should remember for the coming lectures we learned about the different domains of life and here I highlighted the difference of AIA to bacteria which is

Really important for the coming lectures we also talked a bit about ukar in the coming lecture we will talk hardly about ukar but then in the very last lecture we will take this uh topic up again um yeah then we talked about plants alga as primary producers of biomass in

Regard to this circular way or this way of circular thinking and we also highlighted the problems in the degradation of lignine um also in regard to hemicellulose and cellulose but the last two are somehow still accessible for biogas plants and for the liin we need really heavy treatment and then we

Have this discussion about whether we really should throw liid into a biogas plant or not we also he about some representatives of the protoo which are really important for Waste Water treatment this is actually the reason that we have this formation of flocks at all without them water treatment would

Not be possible at least not in the way as we know it and then we highlighted in this circle of biomass um the possibility to recycle and reuse biomass and we will focus in the coming lectures especially on this in regard to anerobic digestion so with this we are done um we

Still have uh 25 minutes minutes so I think we can already start the next presentation I provided the presentation so can we open it please thank you do you have any questions so far anything was unclear could you follow everything okay great so wait a minute we have to a there it is

Already okay so we will just get started with this um we will finish this lecture the next time tomorrow um but we will at least get started so we are now in the second lecture of this complete module on photosynthesis and we will talk a little bit about photosynthesis in general how

It works then we will talk about so-called C for plants and C plants have you hear about them there’s a really famous C4 plant which is used a lot here in in Mexico it’s corn this this is one of the best examples for a C4 plant but we will talk

About it in detail to explain you how it works and then we will also get it taste how photosynthesis might be relevant for circular economy so where is actually the connection between photosynthesis and waste management so one importance is the mineralization of waste so that we can

Create or produce an extract of minerals which we can use to um produce crop and to grow biomass again we have the possibility to use carbon dioxide which is one of the main substrates for plants you know this already we have the possibility to use uh waste as a substrate for very

Specific organisms to produce actually something which is not Just Energy or heat we can use it for example to grow micro algae for the production of certain Pharmaceuticals and we can also combine this topic with biotechnology in order to make plants more efficient which might also affect

Our concept of Waste Management in the end so what is this what I’m showing here it’s a plant yes it’s a part of a plant it’s not an entire plant yes chloroplast that’s right that’s a chloroplast that’s where we have our photosynthesis so at this point I will go into an

Article which I found really nice I mean um photosynthesis is already investigated really well and and we find it in many school books but I found this article and I think uh they summarized the concept of photosynthesis really nice so I I recommend it to

You and here you see a first scheme of Johnson at all that’s the the author of this article what photosynth is is actually about so here we start here we have our sunlight and we want to use the sunlight somehow to retrieve energy and eventually biomass so what is happening here what’s this

Process what is happening with the water yes that’s right it’s kind of an electrolysis we use the energy from the Sun to make some kind of uh plant internal electrolysis in the chloroplasts to split it into oxygen and then we have the hydrogen and the hydrogen is used to chemically reduce carbon

Dioxide and then we have have already something close to polyes in the first place they the plant wants to use this to build up its its um biomass to to grow but eventually they also need energy so they are also degrading this biomass eventually so they produce hydrogen again they also

Using oxygen for this so they perform a kind of respiration to produce electricity um or energy in a chemical way conserved that they can use it and then they also dissipate heat here you see a chloroplast this is a very simple way to show how a plant cell looks like we have

Our nucleus we have a so-called vaku which is important important to regulate the osmotic pressure we have the chloroplast which I just showed here as green dots and we have the cell membrane with a cell wall this is really simplified and then if we magnify this Green Dot here the chloroplast then it

Looks like this so it gets even more complicated we have here a network of so-called Tyler Crees many Tyler assembled together to one granum we have several Grana in our chloroplast and then we have a double walled system which the cell uses to build up some gradients in in protons to

Create an proton gradient that can later on be uh converted into to chemical energy that a plant can use here’s the basic chemical reaction that takes place when we talk about photosynthesis so here we have the light reaction and then we have a dark reaction so not everything is happening

Uh in the presence of light and in the presence of light we have the um disruption of of water as you mentioned before we need the light and then we produce oxygen protons electrons so this is important so we could also say we just produce hydrogen but actually the the cell is separating

Protons and electrons and we have a different let’s say mass flow for for these and um I will show it in more detail later on and then we have the dark reaction here we are using the carbon dioxide which the plant is taking up eventually and it uses protons and El

Electrons to chemically reduce the carbon dioxide to produce this minimal poite which is then later on used to produce more biomass we have here this Delta G do you know what a Delta G is yeah I think it’s more familiar to you then to me you’re all

Engineers um still I wanted to show in a really simple way so you can show it with these two balls and when this ball falls down it is doing it freely so there is like potential energy uh which can be converted in kinetic energy and this

Happens um on itself when Delta G is uh negative negatively and then if we want to lift up this ball then we have to apply actively energy to the system and then the Delta G is positive okay now it’s going to be step by step a bit more complicated so here

We see again the chloroplast and we see the Tyler Crees inside and here we can separate between the light reaction and the dark reaction of course this separation is not physically present so in the chloroplast everything happens at once everywhere um but to systemize it to better understand

It we can say we have here on the left side the light reaction and then on the right side we have the dark reaction during this light reaction we produce something called ATP and nadph have you ever heard about these substances is it completely new for you or have you ever heard about

It okay so I have the feeling you have seen it but you can’t completely comprehend what’s what’s behind it okay we will discuss some of these terms and we will start with the ATP ATP is the way how life is using energy this is the full name it’s really

Long and you don’t have to remember it if you remember just ATP I’m absolutely happy with this and to create this ATP we need the ADP ADP is the same as ATP just one phosphate group less and to bind this phosphate again to the ADP we have to apply energy to these

Substances and then they will fuse together they form the ATP and this is a highly energetic substance which can then kind of push um sub um um processes in the cell which are in need of energy this is seen here so here we have the ATP and then the phosphate separates

Again from the ADP the electricity or the energy um gets free and can then be used to power all kind of reactions which wouldn’t take place otherwise then we have the nadph the name is even more horrible and you don’t have to remember it either I

Will not read it now we just remember it is nadph and this is a bigger molecule which is needed as a kind of Transport vehicle for protons and electrons if you remember this formula we have here the release of protons and electrons and they can be transported to any kind of chemical

Reaction using this nadph then we have the chloroplast which we know already it’s like a subcellular organel this is a bit easier to comprehend and then we have the stroma it’s well basically the liquid which is filling the chloroplast I know this is difficult to to understand or to remember if you

Never worked on on biochemistry but I encourage you to to do so because in the further course of the lecture we will talk at multiple positions about ATP and nadph so therefore it’s really important that you remember these terms so then we have the light reaction which takes place in the Tyler greets

And then the dark reaction um is focused on the so-called Calvin cycle we will see the Calvin cycle in a moment it’s like a complex um chain reaction that takes place over and over again in order to enrich biomass to produce biomass so um I will show this later and

Now we want to see in more detail what is actually happening inside the Tyler creates so I think everyone is now a bit overwhelmed from this drawing it’s quite complicated but again it’s important because in anerobic digestion uh we will also talk about electron transport chains um so those

Are kind of um there are Universal reactions involved which are taking place in the photosynthesis but also otherw so I think it’s good to um get introduced in some biochemical Concepts and then later on it’s going to be important when we talk about the the possibility to actually improve anerobic

Digestors applying light it’s an hypothesis that we still have and there are some um nice evidence that this really has an impact and to understand why we believe so we need to understand what’s happening here so you don’t have to understand everything at once we will now move step

By step through this whole scheme and we start with the sun which provides our ATP and the nadph which we know already so this is the first step and now we’re trying to Cluster this step step by step U or this process step by step in a more complex

Concept this we know Al also and we start start with the so-called photosystem 2 it might appear strange that we start with the photosystem 2 but this is just because historically we found the photosystem 2 first and then later we found the photosystem one which cames in

It in its radi action actually a bit later and here in this photosystem two we have the electrolysis that we talked about earlier so it’s an energy harvesting complex and it harvests light from the sun and the more energy it collects the more reactivity it has and at some point the

Reactivity is enough to disrupt the the water to disrupt it into the electrons the hydrogen and um uh the electrons and the protons and the the oxygen yeah here some are some terms which we also need to understand uh pigments I guess you know pigments are substances

Which are able to take up wavelengths from from the light to to collect the energy and then we have the so-called firster resonance energy transfer this is how light is collected and transferred to one point where then the electro Electro IIs takes place don’t worry we will take a deeper look at this

As well so maybe you have seen in your Chemistry lectures the so-called jablonski diagram anyone remembers yeah you’re noing so um what we are seeing here is fluorescence we have electrons they receive some energy and they jump on a outer shell one shell higher or two and then

They can jump back and then the energy is released as a certain wavelength so this you know already what’s phosphor resense what’s the difference between fluoresence and phosphor resense no both need energy both are glowing processes both can glow in the dark okay I will resolve it if you have

An uh excitement and the electrons jump onto shell two there could be like an internal relaxation so it could jump here and if then the electron jumps back and light is released then we call it phosphor resense but if the electrons jump back from the original state then it’s called

Fluoresence but both processes are actually about um a glowing process based on energy that is released from electrons which are jumping back to a lower shell you can also show it with the bore model so here we have our electron surrounding the nucleus and then the electron is excited

Jumps back not back jumps on the outer shell and then eventually it jumps back to release some energy in form of W length you can show it also like this so here have you the lower shell and this is in an excited state and you can actually lower the

Electron to transfer the energy um on another electron which you have here so that this jumps up again and here we are already talking about the energy transfer so what we usually know is that the electron jumps up jumps back and then light is released but we could have an

Radiation free transfer of the electron from here to um to the acceptor and then it jumps back there and the um energy or the the light is is released there in order to allow this energy transfer the this radiation free transfer of light we need an overlap of the emission spectrum and the

Exitation Spectrum so if we have one molecule which is able to um emit light with a certain wavelength which would be able to excite another molecule then it’s possible that the energy directly jumps over without any radiation produced and that’s what uh we call threat a guy named firster was

Describing this for the first time as I know and uh so this stands for firster resonant energy transfer why is this important because we need to achieve a sufficient energy density to allow the electrolysis of our water so imagine that all these pigments here are collecting

Energy but then the energy is not enough to split the hydrogen uh the water so what the photosystem 2 is now doing they’re conducting their their energy with this spread this with this energy uh transfer to the so-called reaction Center so you have a continuous flow of energy into the center and like

This the energy accumulates until eventually we are able to electroly the water to produce the oxygen and the electrons and the protons here’s another way which shows basically the same here we have the sun we have a pigment and it uh takes up some energy from the Sun and then it

Conducts the energy further in another pigment without without any radiation and then all the energy is collected here in the reaction Center and we reach then an energetic level which is high enough to uh destroy the water molecules and to release relase the electrons that are used then in the further

Process there are many pigments and some of them are actually quite interesting for for the industry so they’re extremely um interesting for the pharmaceutical industry and they would have a really high value so the value of selling this would be much much higher than selling methan or electricity if we could produce

Something like this from biogas this from biogas processes this would be nice and there was actually an an art the industry yet so this is still on an academic level so they described it in regard to the color industry that’s the article evaluation of chlorophyll and antioxidative components harvested from

The anerobic digestion of fruit and vegetable waste um I have a short explanation here for you later on but I will just explain it now with my own words so basically if you throw in your plants into the biogas process they will be degraded as much as possible and

Everything will turn into methan but then if you have like um pre-stage where you incubate your plant material just for a short moment before you then um transfer the material further into the main biogas plant you can actually collect a metabolic which is not fully degraded yet and this metabolite contains these different

Pigments so this is an um interesting site story and why do we actually have so many pigments why why don’t we have just one pigment for the photosynthesis different W yes exactly that’s the right answer so we have different wavelengths and here you see an absorption Spectrum for chlorophyll a

It’s the the green line so here it absorbs very well then for a while there happens nothing and then between 600 and 700 nanometers there is again a really good um absorption then we have the blue line which is Chlorophyll B and the yellow line which is uh better curtins and you

See they are all a bit shifted so the the more pigments we have uh the wider is the range of wavelengths that we actually can collect okay now back to our photo system We Now understand the importance of pigments we understand that they’re really important for the industry would

Like to collect them but they are also in the photo system too and there they are playing a major role for the photosystem to so that they can um collect the necessary energy for electrolysis and now we start with the so-called electron transport chain so the protons are released here for the

Moment they just remain there and we are building up a big gradient of protons which we will discuss later again but the electrons they are now jumping over to a molecule called cytochrome BCF complex leaving is so late already oh yeah the time is over

So sorry we stop here we will uh start here again tomorrow thank you very much for your attention if you have any questions you can still ask them um you can also ask them tomorrow as you wish so thank you very much graas told look for e O