The
FAU-Food Chemistry work group is highly interested in the
bioactivity and functionality of food components. Our studies are based
on
sophisticated analytical and bioanalytical methods, allowing for the
unequivocal characterization of the molecular structure of active
compounds.
The bioactivity of the food components is studied in cell-based assays
as well
as in human intervention studies, which are carried out in cooperation
with the university hospitals in Erlangen.
Non-enzymatic
posttranslational modifications of proteins and peptides
Immunomodulating activity of
roasting products
DNA-Glycation
Development
of bioanalytical and mass spectrometric methods in food analysis
Sensory properties
Non-enzymatic posttranslational
modifications of proteins and peptides
During
food
processing, proteins and peptides undergo fundamental chemical
modifications, which considerably influence their physiological and
toxicological properties. The most prevalent non-enzymatic
posttranslational modifications are oxidation, glycation (AGEs), and
Maillard reactions. Similar processes also take place in the human
organism, having a major impact on the development of diseases related
to diabetes, kidney failure, and ageing. Using mass spectrometry, the
FAU-Food Chemistry workgroup can systematically monitor these
non-enzymatic posttranslational modifications and quantify them
time-dependent and specific for each product and binding site. In a
pilot intervention study, we investigated the relationship between the
intake of AGEs by industrially produced infant formulas and endogen
formation in infants.
Immunomodulating
activity of roasting products
In
addition to
protein modifications, the reactivity of carbohydrates during food
processing also triggers the formation of a variety of other products.
In severely heated food products, sugars react with other low molecular
components, such as amino acids or polyphenols. The roasting of coffee,
for example, has been shown to produce amino reductones or oligomeric
melanoidins, leading to activation of macrophages by nuclear
translocation of NF-κB and finally to apoptosis.
Macrophages are essential to the healthy intestinal immune system. When
out of metabolic balance, they contribute to the development of
inflammatory bowel diseases, such as Morbus Crohn. Activity guided
fractionation has allowed the FAU-Food Chemistry work group to identify
the bioactive molecules in coffee.
DNA-Glycation
Similar
to proteins,
DNA can also be modified by sugars and/or their reactive degradation
products (carbonyls) in a process referred to as DNA glycation,
resulting in the formation of DNA-AGEs. The carbonyls are either
ingested with the diet (or medical products) or formed by metabolic
processes directly in the human organism. With the discovery of
carboxyethyldesoxyguanosin (CEdG), an
important marker has been found, which can be used to monitor the
development and
consequences of DNA glycation in vivo or in cellular model systems. Our
research has shown that CEdG residues, which were synthetically
introduced into DNA, have the potential to increase the mutation rate.
Development of bioanalytical and mass
spectrometic methods in food analysis
The
FAU-Food
Chemistry work group is also thoroughly interested in the development
of
highly sensitive and selective bioanalytical and mass spectrometry
methods and their application to food analysis. In collaboration with
the Institute of Biochemistry and Molecular Medicine, for example, we
have developed a novel marker for the immunochemical analysis of CNS
contamination in meat and meat products. The consumption of CNS tissues
can
increase the risk of BSE transmission from cattle to humans.
Sensory Properties
Although
the visual
impression is very important during food intake, our olfactory sense is
still
more involved in the assessment of foods. With about 350 odor
receptors, the human nose can discern several thousands of different
aromas and such has decisive influcence how appetizing we consider a
meal.
A junior research group headed by Dr. Andrea Büttner explores the impact of odors on neonatal nutrition. These investigations could play an important role in the understanding of neonatal and subsequent food preferences and in the development of diet-related diseases.