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Ph.d.

Fremtidens forskere inden for ingeniørvidenskab støbes hos os. Vores ph.d.-studerende har høje akademiske ambitioner og leverer resultater af høj kvalitet til både den private og den offentlige sektor. Vores hovedfokus er anvendt forskning, og vi har et stærkt samarbejde med branchen for bio- og kemiteknologi, fordi vi forstår dens kerneudfordringer og bidrager til at udvikle løsningerne.

Her på siden kan du møde nogle af vores ph.d.-studerende og læse om deres projekter.


AU-ingeniør hædres for sit arbejde med at udvikle batterier til lagring af grøn strøm

Civilingeniør og ph.d. Kristina Wedege modtog i 2019 Aarhus Universitets Forskningsfonds ph.d.-pris. Hun sætter pris på, at andre kan se værdien i hendes arbejde med at gøre lagringsteknologi til vedvarende energi mere grøn.

Hvis Danmark skal køre på vedvarende energi i 2050, som planen er, er vi nødt til at kunne lagre sol- og vindenergi. Et af tidens hotteste emner er derfor at finde egnede, teknologiske løsninger på denne udfordring, og det er netop hvad kemiingeniør Kristina Wedege har forsket i gennem sit ph.d.-projekt – et arbejde, som hun nu modtager den prestigefyldte Aarhus Universitets Forskningsfonds ph.d.-pris for.

Kristina Wedege er uddannet civilingeniør i kemi og bioteknologi fra Aarhus Universitet. Uddannelsen er også i høj grad en af grundene til hendes fascination af flowbatterier til lagring af grøn strøm. Foto: Claus Sjödin
Kristina Wedege er uddannet civilingeniør i Kemi og bioteknologi fra Aarhus Universitet. Uddannelsen er også i høj grad en af grundene til hendes fascination af flowbatterier til lagring af grøn strøm. Foto: Claus Sjödin

Medium and reaction engineering of enzymatic cascade for furan-dicarboxylic acid synthesis

Milica Milic
Milica Milic

Plastics originating from fossil fuels have long been a problem for our environment, and with the doomsday clock never closer to midnight, we need to find a way to employ renewable resources for plastic production. One possible way to do this is to use enzymes to transform sugars into valuable chemicals which will later be combined into a completely biobased polymer to replace PET.

The goal of my project is to establish an enzymatic cascade reaction for production of 2,5-furan-dicarboxylic acid (FDCA). FDCA, along with ethylene glycol made from sugar, can then be used to create polyethylene furanoate (PEF), a 100% biobased polymer, which could become a green alternative for everyday plastics. The reaction will be performed with enzymes attached to solid supports and placed in a rotating bed reactor. Another focus of the project is to perform the reaction without water using different organic solvents, and to examine their effect on reaction productivity.

This project is a collaboration between Aarhus University and the company SpinChem in Umeå, Sweden, and is part of the Horizon2020 Marie Skłodowska-Curie Innovative Training Network INTERfaces.

ABOUT THE PROJECT


Project title: Medium and reaction engineering of enzymatic cascade for furan-dicarboxylic acid synthesis 

PhD student: Milica Milić

Contact: milic@eng.au.dk

Project period: Oct 2020 to Sep 2023

Main supervisor: Selin Kara 

Co-supervisor(s): Emil Byström (SpinChem, Sweden) 


Profiling the degradation and toxicity of short-chain per- and polyfluoroalkyl substances (PFAS) in water

Per- and polyfluoroalkyl substances (PFAS) are a class of man-made chemicals that have unique properties, such as amphiphilic nature, and thermodynamic, physical and biological stability. PFAS are detected in the environment globally and have adverse effects on human’s health. Since 2002, PFAS manufacturers started to replace long-chain PFAS with unregulated short-chain PFAS (typically with carbon number less than 7), which were consequently widely used but not fully investigated. Short-chain PFAS are already found in the environment (concentrations range from ng/L to µg/L). They are less adsorbable, are transported over longer distances in the environment and may persist longer in the environment and organisms. They may also have more serious adverse health effects, but this aspect has not been fully investigated yet. Our knowledge to efficiently remove short-chain PFAS contamination from wastewater to prevent adverse effects in humans and the environment still remains limited.

This project aims to investigate and enhance the potential of photo-catalysis to degrade short-chain PFAS by defluorination. Quantitate and qualitative analysis will be performed by ultra-high performance liquid chromatography - high resolution mass spectrometry. In vitro bioassays will be used to investigate the removal of toxicity caused by PFAS and their transformation products.    

ABOUT THE PROJECT


Project title: Profiling the degradation and toxicity of short-chain per- and polyfluoroalkyl substances (PFAS) in water 

PhD student: Junying Wen 

Project period: Oct 2020 to Sep 2023

Main supervisor: Lars Ottosen

Co-supervisor(s): Leendert Vergeynst & Zongsu Wei


Novel Dual-reaction Centre Fenton-like Catalysts for Effective Degradation of Persistent Organic Pollutants (POPs)

The worldwide release of persistent organic organic pollutants (POPs) has caused serious pollution to the water environment and thus endangered human and ecosystem health. To address this challenge, advanced oxidation processes (AOPs) have become a research hotspot in the field of water purification. Among them, Fenton catalytic oxidation can produce hydroxyl radicals (•OH) that will destroy the structure of organic pollutants without selectivity. However, most of the polyphase Fenton catalysts developed at present are doomed to have low activity, poor stability  and low utilization of oxidants under neutral conditions. Dual-reaction center is a new mechanism of Fenton-like process to avoid problems mentioned above by separating the oxidation and reduction sites.  In this project, we plan to prepare novel Fenton-like catalysts with dual-reaction center and combine with interfacial reaction to degrade POPs rapidly under ultra-low concentration of oxidants. Further, we hope to improve the degradation of pollutants under neural conditions by in-situ production of hydrogen peroxide on the surface of catalysts without adding oxidants.    

ABOUT THE PROJECT


Project title: Novel Dual-reaction Centre Fenton-like Catalysts for Effective Degradation of Persistent Organic Pollutants (POPs) 

PhD student: Zhiqun Xie 

Project period: Oct 2020 to Sep 2023

Main supervisor: Zongsu Wei


Nanobody-based inhibitors of allergen-mediated anaphylaxis

Josephine Baunvig Aagaard
Josephine Baunvig Aagaard

This project focuses on understanding and interfering with the molecular events in allergic reactions. Allergy is a disease in which the immune system reacts to otherwise harmless triggers, allergens, from the environment. Central in the allergic reaction is the binding of IgE antibodies to these allergens. In allergic patients, the allergen-specific IgE antibodies are bound to high-affinity IgE receptors (FcεRI) and causes long-term sensitization of effector cells. Binding of allergens to these IgE/receptor complex leads to activation of the effector cells and triggers immediate allergic reactions and potentially anaphylaxis, which can have severe consequences for the patient.

In recent years, the concept of using single domain antibodies (nanobodies) as therapeutics has gained ground.

In this project, I will explore the potential of using nanobodies as inhibitors of allergic reactions. I will develop and characterize novel nanobodies and nanobody-based formats that inhibit the IgE/allergen interaction and thereby reduce the risk of anaphylaxis during allergen exposure.

  Using nanobody-based inhibitors for immunotherapy in allergic patients could potentially bypass existing long-term allergen immunotherapy concepts or establish new concepts for those allergies lacking immunotherapeutic options so far.    

ABOUT THE PROJECT


Project title: Nanobody-based inhibitors of allergen-mediated anaphylaxis 

PhD student: Josephine Baunvig Aagaard 

Contact: jbaa@eng.au.dk

Project period: August 2020 to July 2023

Main supervisor: Edzard Spillner 


Novel adsorptive composite materials for catalytic ozonation of micropollutants in water

The instability and low solubility of ozone (O3) molecule in liquid phase limit the effective contact between micropollutants and O3/hydroxyl radicals (OH) in water. Thus, the uncompleted utilization of ozone molecule is largely prevalent in O3-based advanced oxidation processes (AOPs). This project hopes to promote O3 utilization by extending the O3 retention time in the liquid phase and enhancing the contact between micropollutants and oxidants. In particular, we will synthesize a uniquely hydrophobic adsorbent with pine-needle-like hierarchical nanostructures that can simultaneously capture O3 molecules and micropollutants. We will later load a catalyst on the surface of pre-prepared adsorbent to realize the efficient oxidative degradation of micropollutants on the surface of this composite. To investigate the performance of the prepared material, we will select herbicide glyphosate (Gly, N-(phosphonomethyl) glycine) as a model micropollutant and study the degradation pathway.    

ABOUT THE PROJECT


Project title: Novel adsorptive composite materials for catalytic ozonation of micropollutants in water

PhD student: Xingaoyuan Xiong 

Project period: Oct 2020 to Sep 2023

Main supervisor: Zongsu Wei 

Co-supervisor(s): Alberto Scoma 


Hydrothermal liquefaction and analysis for wastewater sludge valorization and immobilization

Lars Bjørn Silva Thomsen
Lars Bjørn Silva Thomsen

Wastewater treatment sludges are an increasing threat to the environment and health due to high levels of organic micropollutants such as pharmaceuticals, microplastics, and pathogens. Due to the high phosphorous content of sludges, they are commonly applied to land as a fertilizer, but this results in pollutants emerging into the food chain. However, these so-called solid wastes can be a source for hydrocarbon fuel production due to its high content of organic carbon.

The Ph.D. project will investigate the high temperature and pressure thermochemical processing technology, hydrothermal liquefaction (HTL) to convert sewage sludge into high-value bio-crude. The process mimics natural fossil fuel creation and the bio-crude can be upgraded into a drop-in diesel and jet fuel as well as carbon-based chemicals and materials.

The high temperature can effectively immobilize pathogens and convert microplastics to bio-crude. However, the process water generated from HTL process is very high in COD, which needs to be addressed to facilitate HTL integration into WWTP, increasing the overall carbon yield. Novel wastewater treatment technologies such as wet air oxidation (WAO) and microbial electrolysis cells (MEC) will be investigated as options to reduce COD levels from HTL process water, to generate heat, and to produce the H2 required for bio-crude upgrading.    

ABOUT THE PROJECT


Project title: Hydrothermal liquefaction and analysis for wastewater sludge valorization and immobilization    

PhD student: Lars Bjørn Silva Thomsen 

Contact: lthomsen@eng.au.dk

Project period: May 2020 to May 2023

Main supervisor: Alberto Scoma 

Co-­‐supervisor(s): Alberto Scoma and Konstantinos Anastasakis 


Exploring natural and artificial biofilms of acetogenic bacteria to improve microbial electrosynthesis rate

Microbial electrosynthesis is a novel biotechnological process for the conversion of electricity and CO2 into biofuels or other organic compounds. Microbial electrosynthesis could in the future contribute to the desired lowering of CO2 emissions, while at the same time storing excess renewable energy and producing sustainable biochemicals.

Microbial electrosynthesis is carried out by acetogenic bacteria (e.g. Sporomusa ovata), which are capable of reducing CO2 to organic compounds, using an electrode as the electron donor. One of the major obstacles that limits the rate of microbial electrosynthesis, and hence its upscaling beyond lab-scale, is the low number of cells that attach to the electrode. Currently, very little is known about attachment and biofilm formation by S. ovata. The goal of this project is to increase the cell numbers of S. ovata on the electrode, using two different strategies. First, natural biofilm formation will be stimulated and investigated. Second, artificial biofilms will be created by immobilizing cells in polymeric matrices. The different types of biofilm will be characterized using state-of-the art techniques (microsensors, confocal microscopy, etc.) and the effect of increased cell numbers on the electrode on microbial electrosynthesis rates will be investigated. 

ABOUT THE PROJECT


Project title:  Exploring natural and artificial biofilms of acetogenic bacteria to improve microbial electrosynthesis rates     

PhD student: Louise Vinther Grøn 

Contact: louise.groen@eng.au.dk

Project period: May 2020 to May 2023

Main supervisor: Assistant Professor Jo Philips 

Co-­‐supervisor(s): Assistant Professor Klaus Koren and Associate Professor Alberto Scoma 


Designing intumescent coatings - a fundamental study

Iben Hansen-Bruhn
Iben Hansen-Bruhn

 

The aim of the project is to obtain a fundamental understanding on formulation of intumescent coatings for passive fire protection and express the understanding in the form of key material performance indicators, correlations, and predictive formulation models.  Intumescent coating research is due to its complexity, commonly done by trial-and-error and incremental formulation changes without in-depth scientific understanding. The absence of a correlation between material properties and chemical composition has led to this formulation approach. It is clear, that standard test methods and the complexity of the reactions, makes it extremely difficult to correlate material properties and fire-retardant performance. Therefore, a deeper understanding of these reactions and material properties and their contributions to fire-retardant performance is greatly needed to enhance fire retardant performance and cost reduction on developing and producing fire retardant paint.

ABOUT THE PROJECT


Project title: Designing intumescent coatings - a fundamental study

PhD student: Iben Hansen-Bruhn

Contact: iben.hansenbruhn@eng.au.dk

Project period: May 2020 to May 2023

Main supervisor: Assoc. Professor Mogens Hinge 

Co-­‐supervisor(s): R&D Team Manager, Jens Ravnsbæk, TEKNOS A/S 


Programmable Synthesis of Designer Lipids and Phospholipids -­‐ Linking chemistry and physics with function and manufacture

Oliver Bogojevic
Oliver Bogojevic

This project is anchored within the research fields across the chemistry behind synthesis of fats, 3D printing manufacturing and food physics; particularly in design and synthesis of novel lipids/fats, programmable purification, modeling and application in 3D printing food. Fats or lipids are ubiquitously occurring in almost all organisms, not only as structural molecules for cell membranes, but also take on various biological functions. The project aims to develop and construct a library of structural different lipids with distinct characteristics, by establishing new efficient conditions and optimizing already established procedures for the synthesis of lipids. Incorporation of the designed lipids with other suitable ingredients will constitute the ink (“bioink”) in a new established 3D printing system. Computational modeling will have a central role to understand the chemistry and interactions between the actual constituents in the bio-ink and the direct dynamics with the materials of the 3D printer system. This is of major importance in order to design a robust system with efficient control and understanding of factors as reproducibility, mechanical strength, print speed and scalability etc. The ultimate goal of this project is to create product arrays of new lipid molecules with documented programmability and standardized protocols. It is to generate sufficient scientific knowledge and technology for building up a 3D printing platform for food applications.

ABOUT THE PROJECT


Project title: Programmable Synthesis of Designer Lipids and Phospholipids -­‐ Linking chemistry and physics with function and manufacture

PhD student: Oliver Bogojevic

Contact: olbo@eng.au.dk

Project period: June 2020 to May 2023

Main supervisor: Zheng Guo

Co-­‐supervisor(s): Jens Vinge Nygaard, Lars Wiking



Electrospun 3D Nano-biointerfaces for non-invasive stimulation of excitable cells

Alongside the widely studied pathways of biochemical regulation by chemokines, cytokines and growth factors, one often-overlooked but significant influence over the behaviour of biological systems is electrical/electromagnetic signaling. Biological systems are rich in electrical activity. In particular, neural activities are precisely controlled by the membrane potential, which modulates either neuronal firing to trigger the signaling transporting over long distances. Inspired by the nanoscale features at cellular surface components (e.g., microvilli and filopodia) and extracellular matrix, the interactions between live cells and nanostructured materials in cellular environment have been studied. A unique technique that has gained tremendous attention in the last decade as the most robust, straightforward nanofiber processing method is electrospinning, which utilizes high voltage electric fields on extruded liquid containing virtually any polymers, composites or supra‐molecules to generate continuous submicron fibers.

This PhD project is aimed to apply the electrospinning technology and tissue engineering tools to build biocompatible fibrous hydrogel nanobiointerfaces that recapitulate the 3D in vivo environment for non-invasive stimulation of excitable cells. It will mainly involve the study of electrospinning of different synthetic or biopolymers with control over mechanical and topographical properties, surface chemistry and characterizations, bioconjugation, in vitro cell biology assay and in vivo animal studies.

ABOUT THE PROJECT


Project title: Electrospun 3D Nano-biointerfaces for non-invasive stimulation of excitable cells 

PhD student: Jordi Amagat Molas 

Contact: jordi@eng.au.dk

Project period: Nov 2019 to Oct 2022

Main supervisor: Menglin Chen 



Unveiling the role of H2 in the cathodic electron uptake by acetogenic bacteria

Laura Daniela Munoz Duarte

Some acetogenic bacteria have the capacity to use cathodes as electron donor for the reduction of CO2 into more complex compounds like acetate. This capacity can be applied for the development of highly interesting technologies, such as microbial electrosynthesis. This biotechnology combines the upgrading of CO2 to biofuels with the storage of excess renewable electrical energy. So far, however, the mechanisms by which acetogenic bacteria obtain electrons from cathodes are not well understood.

The objective of this PhD is to investigate the role of H2 as a mediator in the cathodic electron uptake mechanism of acetogens. This work will determine the H2 threshold of several acetogenic strains and measure the H2 partial pressures at the cathode surface. In addition, the role of H2 in the electron uptake from metallic iron (Fe(0)) by acetogenic bacteria will be examined. The latter process is highly analogue to the electron uptake from cathodes and plays an important role in microbial induced corrosion. The elucidation of the cathodic electron uptake mechanism of acetogens will allow to optimize microbial electrosynthesis and will contribute to its further development.   

ABOUT THE PROJECT


Project title: Unveiling the role of H2 in the cathodic electron uptake by acetogenic bacteria

PhD student: Laura Daniela Muñoz

Contact: laura.munoz@eng.au.dk

Project period: Oct 2019 to Sep 2022

Main supervisor: Assistant Professor Jo Philips

Co-supervisor: Associate professor Alberto Scoma


Novel methods for measuring gaseous emission dynamics from open sources

Yolanda Maria Lemes-Perschke
Yolanda Maria Lemes-Perschke

The aim of this project is to implement and validate methods for measuring emission of harmful gases from open sources in agriculture with focus on greenhouse gases (GHG, methane and nitrous oxide), ammonia (NH3) and odour emission from stored livestock manure.

A key part of the study is to:

  • Understand the chemical and microbial processes that influence GHG and NH3 emission      from the stored manure.
  • Combine novel micrometeorological flux measuring techniques with state of art gas measuring instruments (Cavity Ring Down Spectroscopy and Proton Transfer Reaction Mass Spectrometry equipment - PTRMS).
  • Validate the novel measuring method.

During the study, the methods shall be used to provide valid measurement of the annual emission of GHG and NH3 from full-scale manure store on Danish farms. The data is needed for calculating the annual national gas emission inventory, which must be send to the EU in accordance with the Gothenburg protocols.

ABOUT THE PROJECT


Project title: Novel methods for measuring gaseous emission dynamics from open sources

PhD student: Yolanda Maria Lemes-Perschke

Contact: ymlp@eng.au.dk

Project period: Sep 2019 to Aug 2022

Main supervisor: Assoc. Prof. Anders Feilberg

Co-supervisors: Senior Advisor Tavs Nyord and Prof. Sven Gjedde Sommer



Nitrogen transformation and greenhouse gas emissions from soils amended with organic waste and derived fertilizer products

Yihuai Hu
Yihuai Hu

This project is part of an interdisciplinary cross-sectoral European Training Network “REFLOW” entitled “Phosphorous Recovery for Fertilisers from Dairy Processing Waste”. The REFLOW research will (1) mitigate the environmental impact of dairy processing waste on soil and water, (2) provide safe environmentally-sustainable, cost-effective closed-loop solutions for crop nutrient management (3) meet the demand for skilled professionals to support the technical, regulatory and commercial development of the market for recycled phosphorous fertiliser products.

This project is aimed at developing an understanding of the chemical and microbial processes that influence greenhouse gas (GHG) emission (methane and nitrous oxide) and transformation of nitrogen and carbon in the organic waste and fertilizer products following application to soil. The project will include the following activities:

  • Chemical and physical characterization of organic wastes and fertilizers.
  • Laboratory incubation studies on N and C transformation and emission of CO2, N2O and CH4.
  • Field experiments with organic wastes and fertilizer products to measure crop N uptake and N2O, CO2and CH4 emission.
  • Apply or develop a model of GHG fluxes from soils amended with organic waste and fertilizer products.

ABOUT THE PROJECT


Project title: Nitrogen transformation and greenhouse gas emissions from soils amended with organic waste and derived fertilizer products

PhD student: Yihuai Hu

Contact: hyh@eng.au.dk

Project period: Sep 2019 to Aug 2022

Main supervisor: Prof. Sven Gjedde Sommer

Co-supervisors: Assoc. Prof. Sasha D. Hafner


Processing of brown juice from leaf protein concentrate production for high value-end applications

Natália Hachow Motta dos Passos
Natália Hachow Motta dos Passos

Green biorefineries are integrated multi-product systems for efficient and sustainable production of food, feed, bio-based chemicals and materials from green biomasses. This multiple product approach requires the valorization of any side streams in order to ensure the economic sustainability and success of the overall process.

Brown juice is a nutrient-rich liquid side stream generated in large volumes during leaf protein concentrate production from grasses, lucerne and clover within a green biorefinery. Brown juice contains sugars, peptides and amino acids, organic acids and minerals. 

This project aims to investigate the possibilities of processing brown juice into high-added value products. Technologies such as membrane filtration and fermentation will be evaluated and compared using a techno-economic approach. As brown juice is a complex and varying mixture, further research is necessary on mapping its composition and characteristics over time, and on the viability of its processing into valuable products such as chemicals and materials.

ABOUT THE PROJECT


Project title: Processing of brown juice from leaf protein concentrate production for high value-end applications

PhD student: Natália Hachow Motta dos Passos

Contact: nhm@eng.au.dk

Project period: Aug 2019 to July 2022

Main supervisor: Prof. Lars Ditlev Mørck Ottosen

Co-supervisors: Assistant Prof. Morten Ambye-Jensen


Pre-treatment technologies for enhanced biodegradability of sludge and lignocellulosic biomass in anaerobic digestion

Cristiane Romio
Cristiane Romio

Anaerobic digestion (AD) is a process by which microorganisms transform organic materials (such as manure, crop residues and wastewater sludge) under oxygen-free conditions into biogas, nutrients and additional cell matter (Montané et al., 1998). Biogas has CH4 and CO2 as main components and it can be used for heat and electricity generation, as a vehicle fuel and as a substitute for natural gas (Weiß et al., 2016).

In the first step of AD, hydrolysis, microorganisms produce and excrete enzymes that breakdown and solubilize large molecular structures into smaller components (Parawira et al., 2005). Hydrolysis has been considered as a rate-limiting step of AD and its efficiency can be increased by biomass pre-treatments, which aim to change the material structure and make it more accessible for enzymatic attack.

This PhD project will focus on the enhancement of biogas production through the application of biological pre-treatment on biomass, such as ensiling, enzymatic and fungal aerobic pre-treatments. Enzymatic pre-treatment simply applies industrial enzymes to the biomass to increase hydrolysis efficiency. Fungal pre-treatment relies on the capability of some fungi on selectively decomposing lignin (a fraction of plants which is useless for AD). This way, cellulose and hemicellulose (plant fractions relevant for AD) get more accessible for further AD. Ensiling is based on the preservation of biomass under anaerobic conditions, using bacterial fermentation to prevent further degradation. The low pH achieved by the acids produced during bacterial fermentation inhibits the activity of other microorganisms (Teixeira Franco, Buffière, & Bayard, 2016). Due to the low pH, a slow hydrolysis takes place, which can improve biogas production (Martínez-Gutiérrez, 2018).

 

References:
Martínez-Gutiérrez, E. (2018). Biogas production from different lignocellulosic biomass sources: advances and perspectives. 3 Biotech, 8(5), 233. doi.org/10.1007/s13205-018-1257-4

Montané, D., Farriol, X., Salvadó, J., Jollez, P., & Chornet, E. (1998). Fractionation of wheat straw by steam-explosion pre-treatment and alkali delignification. Cellulose pulp and byproducts from hemicellulose and lignin. Journal of wood Chemistry and Technology, 18(2), 171-191. https://doi.org/10.1080/02773819809349575

Parawira, W., Murto, M., Read, J. S., & Mattiasson, B. (2005). Profile of hydrolases and biogas production during two-stage mesophilic anaerobic digestion of solid potato waste. Process Biochemistry, 40(9), 2945-2952. https://doi.org/10.1016/j.procbio.2005.01.010

Teixeira Franco, R., Buffière, P., & Bayard, R. (2016). Ensiling for biogas production: Critical parameters. A review. Biomass and Bioenergy, 94, 94–104. doi.org/10.1016/J.BIOMBIOE.2016.08.014

Weiß, S., Somitsch, W., Klymiuk, I., Trajanoski, S., & Guebitz, G. M. (2016). Comparison of biogas sludge and raw crop material as source of hydrolytic cultures for anaerobic digestion. Bioresource technology, 207, 244-251. https://doi.org/10.1016/j.biortech.2016.01.137

ABOUT THE PROJECT


Project title: Pre-treatment technologies for enhanced biodegradability of sludge and lignocellulosic biomass in anaerobic digestion

PhD student: Cristiane Romio

Contact: cristiane.romio@eng.au.dk

Project period: June 2019 to May 2022

Main supervisor: Senior Researcher Henrik Bjarne Møller

Co-supervisors: Researcher Michael Vedel Wegener Kofoed


Mining the unexplored microbiome to produce high-value biopharmaceuticals

In nature, microorganisms use enzymes to modify peptides to complex natural products with new and improved properties. Our main hypothesis is that we can exploit the enzymes from known natural products’ biosynthesis to introduce peptide modifications that are currently inaccessible or only accessible through synthetic means.

Our main focus is on Ribosomally synthesized and Post-translationally modified Peptides (RiPPs) expressed as a precursor peptide with a leader and core region. The leader peptide is recognised by co-expressed enzymes, encoded in the biosynthetic gene cluster (BGC), next to the precursor peptide. This means that the recognition sequence is decoupled from where the modification-/s takes place.

In the beginning, we will focus on two different modifications, unnatural amino acids and disulphide mimics contributing to resistance towards proteases, general stability and structural rigidity leading to increased biding affinity. When this is settled, we aim to expand the technology to cover different kinds of modifications and a combination of these.

ABOUT THE PROJECT


Project title: Mining the unexplored microbiome to produce high-value biopharmaceuticals

PhD student: Camilla Kjeldgaard Larsen

Contact: camillakjeldgaard@eng.au.dk

Project period: Feb 2019 to Jan 2022

Main supervisor: Assoc. Prof. Thomas Tørring

Co-supervisors:  Anne Louise Bank Kodal, Novo Nordisk


Hydrothermal liquefaction of waste materials as a key technology for a circular economy of the chemical industry: A systematic approach to solve the engineering challenges

Juliano Souza dos Passos_AU Foto
Juliano Souza dos Passos

Demands for energy, materials and food are intrinsically connected to increasing world population, industrialisation and modern life style. The current linear economic model based on extraction of natural resources and disposal of wastes cannot cope with the societal demands in a sustainable manner.

Hydrothermal liquefaction (HTL) is a thermochemical process that uses hot and compressed water to convert a broad range of carbon-based materials into biocrude – a material similar to crude oil.

The project aims to determine the potential of HTL in relation to converting mixed waste streams that contain synthetic- and bio-polymers, e.g. municipal solid waste, agro-waste, sewage sludge, into biocrude. The technology has shown incredible potential for this application, though the lack of knowledge about the behaviour of such complex waste mixtures under hydrothermal conditions has yet to be addressed.

A future fossil free chemical industry requires new carbon sources. Waste streams containing synthetic- and bio-polymers are an under-utilised option to be considered, so understanding the efficiency, composition and potential of HTL products is necessary if a circular economy is to be achieved.

ABOUT THE PROJECT


Project title: Hydrothermal liquefaction of waste materials as a key technology for a circular economy of the chemical industry: A systematic approach to solve the engineering challenges.

PhD student: Juliano Souza dos Passos

Contact: jsp@eng.au.dk

Project period: Feb 2019 to Dec 2021

Main supervisor: Assistant Prof. Patrick Biller

Co-supervisors: Assoc. Prof. Marianne Glasius and Assoc. Prof. Lars Ottosen


Light-induced biocatalytic reductions

Luca Léo Schmermund
Luca Léo Schmermund

Enzymes have become a recognised and green tool in organic synthetic chemistry due to the generally mild and environmentally friendly conditions required for the reactions. At the time, methods were developed to perform chemical reactions by using light. These light reactions showed an extended substrate scope and proceeded under milder conditions compared to the light-independent alternatives. Therefore, this research project focus on the combination of photoreactions with enzymes in order to obtain sustainable reaction processes. For this purpose, a photoenzyme will be used in this project. Photoenzymes are light-driven enzymes that require light to perform a chemical reaction. Without light, no reaction is possible. The photoenzyme can serve as a starting point to replace hazardous and toxic reagents which are widely used currently in chemical reactions by light. This would be a very important step towards greener chemistry since light generates no waste, is non-toxic and can be obtained from renewable sources nowadays.

The overall goal is to find new reactions that are not feasible with chemical methods at the moment, and to find more sustainable reaction methods by using these photoenzyme. Therefore, a detailed characterisation of the substrate scope and features of this special photoenzyme are necessary. During the project, a secondment at the Aarhus University will focus on the optimisation of the process for industrial relevant applications. Furthermore, an industrial placement is planned at a pharmaceutical company in the UK. There will be the opportunity to work with a newly developed photoreactor and to investigate the influence of different light sources on photobiocatalytic reactions.

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 764920.

ABOUT THE PROJECT


Project title: Light-induced biocatalytic reductions

PhD student: Luca Léo Schmermund

Contact: luca.schmermund@eng.au.dk

Project period: April 2018 to March 2021

Main supervisor: Associate Professor Selin Kara

Co-supervisor: Prof. Dr. Wolfgang Kroutil, University of Graz, Austria


Water oxidation for FMN-dependent redox reactions

Nowadays, our demands on synthetic organic chemistry are higher than ever, and consequently, very specific reactions have to be applied to fulfill these requests. Herein, selective oxyfunctionalizations are of particular interest since they bring up the possibility to produce high-quality bulk chemicals as well as highly valuable fine chemicals. Suchlike reactions can be catalyzed by chemicals, which (often) requires harsh and hazardous conditions resulting in high-cost downstream processes, such as product purification, and suffer from the absence of selectivity.

These challenges can be overcome by the application of environmentally friendly and selective biocatalysts, e.g. enzymes. However, these enzymes in particular oxidoreductases require the assistance of additional components such as other enzymes or cofactors to ensure the catalysis of suchlike complex reactions. For example, oxygenase reactions require (natural) electron mediators, which increase costs in in vitro applications (when applied outside of the cell).

The PhD project “Water oxidation for FMN-dependent redox reactions” aims to overcome this as well as other technical obstacles by using efficient inorganic water oxidation catalysts (WOCs) instead of natural electron mediators. Such artificial mediators apply the energy caused from light to oxidize water into oxygen, while the liberated electrons will be transferred to catalyze the oxygenase reaction. Herein, a natural enzyme-associated compound – FMN – will function as an electron shuttle from the WOC to the enzyme, where the reaction can take place.

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 764920.

ABOUT THE PROJECT


Project title: Water oxidation for FMN-dependent redox reactions

PhD student: Robert Röllig

Contact: roellig@eng.au.dk

Project period: Sep 2018 to Aug 2021

Main supervisor: Associate Professor Selin Kara

Co-supervisor: Dr. Vèronique Alphand and Dr. Katia Duquesne, Aix-Marseille University, France


Extended reach interventions

Johannes Liljenhjerte
Johannes Liljenhjerte

When very long pipes/rods are subjected to a significant compressive load, instabilities can occur in the form of buckling. A phenomenon that can be observed by placing a long slender ruler vertically on a table and then press down its top edge until it starts bending.

This project is focusing on the oil and gas industry where kilometers long coiled tubings (CT) are injected into oil wells (of length up to 12km) for various operations such as removing scales or releasing chemicals. A build-up of compressive forces form due to friction between the CT and well casing. This build-up of compressive forces can initiate different buckling modes along the length of the tubes that eventually end up in a helical shape on the inside of the well. When this happens, friction between the tube and well increases to an extent where the tube locks up inside the well and thus can reach no further.

In this project, a novel solution to reduce friction and provide increased structural integrity for the tube is proposed. The desired properties and viability of the solution are investigated computationally and later experimentally, before introducing it in the field.

Instabilities in pipes/rods appear across various length scales and industries, thus the investigation can find its usefulness in other contexts as well, for example when inserting catheters into the body, jamming nanorods into confined channels or DNA packing inside viral capsules.

 

ABOUT THE PROJECT


Project title:  Extended reach interventions

PhD student: Johannes Liljenhjerte

Contact: jl@eng.au.dk

Project period: Aug 2018 to July 2021

Main supervisor: Associate Professor Jens Vinge Nygaard


Reaction engineering and up-scaling of light-driven in vitro oxidative lactonizations

Alex Cordellier
Alex Cordellier

Lactones represent an important class of substances used in a wide range of applications; however, their current chemical syntheses raise several issues of waste and energy management.

Biocatalytic approaches were developed employing oxidoreductases, namely alcohol dehydrogenases (ADHs) to synthesize lactones starting from diols, using natural cofactors as redox mediators. For the in situ regeneration of these cofactors, different methods have been evaluated so far. Among these recycling strategies, the use of light as the driving force presents the advantages of being applicable in a broad range of reaction conditions and being an environmentally benign strategy with reduced waste generation and energy demand.

Starting from this “green” reaction system, the aim of the PhD study is to develop a highly productive photobiocatalytic process for the synthesis of both bulk and fine lactones. First, a rigorous evaluation of the reaction system, i.e. screening and optimisation of reaction conditions, will be realised to design a suitable reactor type and operation modus. A secondment at the University of Graz will focus on the optimisation of the process by screening different ADHs and evaluating techniques of enzyme immobilisation. The improved process employing immobilised enzyme preparations will then be assessed. The economic and ecological evaluation of the developed process will be performed during another secondment at the Technical University of Denmark. To finish, the up-scaling of the model system will be applied for fine lactone's synthesis during a third secondment with the industrial partner Chiracon GmbH (Germany).

ABOUT THE PROJECT


Project title:  Reaction engineering and up-scaling of light-driven in vitro oxidative lactonizations

PhD student: Alex Cordellier

Contact: alex.cordellier@eng.au.dk

Project period: Aug 2018 to July 2021

Main supervisor: Associate Professor Selin Kara

Co-supervisor: Prof. Dr. Wolfgang Kroutil, University of Graz, Austria


Medium engineering for light driven in-vitro hydroxylation

Markus Hobisch
Markus Hobisch

Enzymes are applied in a wide range of chemical reactions. They can run reactions at mild conditions, saving energy and reducing toxic waste.

During the last years, the use of light for enzymatic synthesis has attracted great attention, especially in oxidoreductase-catalyzed reactions. Water has been applied as the main reaction media for biocatalysis, which, in turn, might result in poor solubility of hydrophobic substrates, consequently, leading to low productivities.

Medium engineering is the solution to overcome this limitation. Instead of water, the use of non-conventional media, e.g. organic solvents or neat substrates, will be evaluated within the PhD study.

A likely side effect of these efforts might be decreased enzyme stability, resulting in lower activity. To ensure sufficient enzyme activity under those non-conventional conditions, various immobilisation methods will be employed to stabilise the enzyme. The enzymatic activity, stability, immobilisation yield as well as protein leaching will be evaluated to elucidate the most suitable immobilisation method.

Besides Aarhus University, this research will take place at TU Graz in Austria and TU Delft in the Netherlands.

Finally, the research results will be used to implement this process at a pharmaceutical company in Germany.

ABOUT THE PROJECT


Project title:
Medium engineering for light driven in-vitro hydroxylation

PhD student: Markus Hobisch

Contact: hobisch@eng.au.dk

Project period: Aug 2018 to July 2021

Main supervisor: Associate Professor Selin Kara

Co-supervisor: Professor Robert Kourist



Tandem catalysis by coupling metal/metalloenzyme for biotransformation and new chemistry

The development of green, sustainable and economical chemical processes is one of the major challenges in chemistry. Besides the traditional need for efficient and selective catalytic reactions that will transform raw materials into valuable chemicals, green chemistry also strives towards renewable raw materials, atomic efficiency and high rates of catalyst recovery. Cascade reactions or tandem reaction, i.e. the combination of chemical catalysis and enzymatic transformations in concurrent one‐pot processes, offer considerable advantages: the demand of time, costs and chemicals for product recovery may be reduced, reversible reactions can be driven to completion and the concentration of harmful or unstable compounds can be kept to a minimum. In addition to the common technical advantages for a typical chemical cascade or multi-component enzymatic tandem reaction, cooperative effects between metal and enzyme may take place if they are well-aligned or intercompartmentalized in a well-structured nano-device or biomimick system. More importantly, both metal-complex and metalloenzyme can be engineered for optimal reaction and enable new-to-nature chemistry in a greener, biocatalytic (chemo-enzymatic hybrid) manner.

Based on this background, the main objectives of project are (1) to develop highly effective tandem catalytic system by coupling metal-complex and metalloenzyme catalysis to enable multi-step or orthogonal reactions; (2) to identify synergitic or cooperative effects between metal/bio- catalysts; (3) to construct or create a nano-device or compatible system for optimal performance for a sequence of precisely staged catalytic steps in a single vessel; (4) to produce value-added biochemicals or enable innovative synthesis for new chemistry by engineering a nano-device or engineering metalloenzyme for promiscuous activities. 

ABOUT THE PROJECT


Project title:
Tandem catalysis by coupling metal/metalloenzyme for biotransformation and new chemistry

PhD student: Rongrong Dai

Contact: diana@eng.au.dk

Project period: April 2018 to April 2021

Main supervisor:  Associate Professor  Zheng Guo

Co-supervisor: Mingdong Dong