Research

Elucidation of aroma and smell compounds in food and non-food items, in the food value chain, and during manufacturing and recycling processes

Our research focuses on the characterization of aroma and smell by elucidating the structure, the occurrence and the origin of aroma and odor compounds. Our concluded and currently ongoing studies, amongst others funded by the Detusche Forschungsgemeinschaft (DFG), deal with the identification and quantification of odorants in a large variety of food and non-food items, like herbs, spices, human milk, wood, plastics or adhesives. Sensory and chemo-analytical techniques applied in our labs include high resolution gas chromatography-mass spectrometry in combination with olfactometric techniques and stable isotope dilution assays. These analyses lay the foundations for a fundamental understanding of the molecular bases of the aromas and smells emitted by the respective items.

Besides answering fundamental scientific questions, our expertise also promotes innovations in applied research, for example with regard to quality and sustainability aspects in the cultivation of food sources from organic farming to aquaculture. Within our project SHIELD, funded by the Bayerische Forschungsstiftung (BFS), we want to improve the quality and safety of food products and enable the design of sensors for assuring food quality in the production and transport chain. In the RASOPTA project, funded by the European Union in the framework of the H2020 Marie Skłodowska Curie Actions – Innovative Training Networks (H2020 MSCA ITN), we work for a sustainable and ecological future of aquaculture as the globally, fastest-growing animal food sector. In our labs, we identify the molecular causes of off-flavour tainting of fish, caused by fish breeding in recirculated water systems and contribute to the development of procedures that alleviate off-flavors in fish, improve product quality as well as environmentally sustainable farming.

Furthermore, we investigate odor compounds and contaminants in materials and products of daily use in order to tackle the problems arising from our constantly growing population and product use. A circular economy and safe products become a significant necessity in nowadays society. Our research group is contributing to this development by designing industrial processes in such a way as to minimize human exposure to potentially hazardous contaminants as well as odor-active compounds. One of our focus points is sustainable human interaction with plastic materials. For implementation of a functional plastics circular economy, major advances in recycling technologies need to be achieved. To address this issue, our research group is part of the C-PlaNeT (Circular Plastics Network for Training) project, funded by the European Union in the framework of the H2020 Marie Skłodowska Curie Actions – Innovative Training Networks (H2020 MSCA ITN).

Investigation of the resorption, metabolisation, excretion and bioactivity of aromatic substances in the human body

The characterization of resorption, transfer, excretion and metabolic processes within the human body after consumption or pulmonary uptake of aroma compounds is realized by in vivo as well as in vitro studies. Recent DFG-funded projects are our intervention studies on the uptake and excretion of aromatic substances in the context of breastfeeding. Moreover, we aim to elucidate physiological (e.g., neurotropic) effects of food constituents and odorants in the human body. Our studies show that some food aromas undergo substantial transformation in the human body. In several collaborative studies, we are investigating the physiological effects of odorants and their metabolites in vivo and in vitro, such as the activation of brain receptor systems involved in sedative and anxiolytic processes, and develop tailored isolation strategies to access complex structures from natural materials. For instance, we recently targeted the isolation of sesquiterpenes and sesquiterpenoids and their modulating activity on human GABA_A receptors.

Understanding olfactory perception: from molecules to perception

Our research group has a long-standing interest in elucidating structure-activity relationships in olfaction, i.e., to unravel the relationship between molecular structure and olfactory perception. Lately, we have been focusing on the description of odor thresholds and odor qualities of guaiacol derivatives, for instance. Beyond psychophysical studies, our group is also elucidating molecular mechanisms of olfaction, e.g., the role of perireceptor events for olfactory perception. A recent collaborative project on aroma metabolism in the olfactory mucosa, funded by the German and the French Research Foundations (DFG-ANR), aims at identifying nasal metabolites relevant to the olfactory perception. Besides studying peripheral processes, we are also interested in central processes during odor detection and perception. For example, we want to understand psychological effects produced by the exposure to odorous materials like wood, or scents used in the design of items as well as living and working spaces.

Smell landscapes: the cultural role of odor in past, present and future

Identification of smell landscapes that define our societies is not only of importance for present and future times, but also for past scenarios that shaped our cultural consciousness. Being part of the Odeuropa project, funded by the European Union’s Horizon 2020 research and innovation program, we explore the odors of the past and identify historically relevant smells. This work will help to create multi-sensory experiences in museums and a better understanding of the volatile substances prevailing in the lifes of our ancestors, in order to promote the wide-ranging role scents and smelling have in our cultural heritage.

Chemical communication: information transfer via molecules

Chemical communication is a widespread phenomenon and used both within and between species for information transfer. One of the research focuses of our group is to elucidate the molecular basis of such information transfer. To achieve this, odor-analytical methods are employed to investigate the volatiles emitted by individuals. At the same time we also study behavioural correlates in the perceiver. Current examples are our research activities on the role of body odors in human chemical communication and the elucidation of chemical and biological principles of body odor formation in an Emerging Fields Initiative (EFI) project funded by FAU (PI: Dr. Helene Loos). In various DFG-funded activities we use sensory-analytical methods to investigate body odors in relation to individual characteristics and variations in chemical signatures. We also apply our methods to research questions in the animal kingdom, e.g., chemical communication in insects and songbirds.

Molecular chemical communication is also at the core of the research training group SymoCADS. Together with our colleagues, we aim at investigating the influence of different release, transport, and sensing principles on functioning of synthetic airborne molecular communication systems at different scales.

Biointerfaces in neurobiological processes

The projects targeted in the Biointerfaces Lab span from engineering tools and interfaces for cellular control to elucidating biophysical interfacial mechanisms and the interrogation of cellular signalling in nervous systems. The junior professor position of Prof. Dr. Danijela Gregurec was funded by the Bundesministerium für Bildung und Forschung (BMBF) for the purpose of promoting this line of research.

Our research here is centered around the development of materials and technologies that aim at controlling neurobiological processes. Therefore, we couple external magnetic fields to corresponding nanomaterials and apply transducers for wireless control of sensory cells. Developing and building biosensors for detection of neurotoxic analytes in vitro and in vivo is another focus area of our research. To design biosensing devices that are fast, miniaturized, and attractive for onsite testing, we use nanoparticle-based biosensing. Neuronal mechanotransduction is our third area of investigation. Here we elucidate transductory mechanisms in neurons. Our focus are mechanosensitive ion channels, such as TRPV4 and Piezo1, endogenously expressed in the peripheral neurons and involved in the sensory perception such as touch, hearing, and pain.