Pronyl lysine
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hexanoate_200.svg)
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| Surname | Pronyl lysine | |||||||||
| other names |
Methyl 2-acetamido-6- (2,4-dihydroxy-2,5-dimethyl-3-oxopyrrol-1-yl) hexanoate ( IUPAC ) |
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| Molecular formula | C 15 H 24 N 2 O 6 | |||||||||
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| Molar mass | 328.36 g mol −1 | |||||||||
| Physical state |
firmly |
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| As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . | ||||||||||
Pronyl-lysine (from P yrrolinon- R educt onyl-lysine ) is a compound that on heating of lysine or lysine-containing proteins produced with sugars and is contained in many foods such as bread, beer and coffee. It is one of the low molecular weight melanoidins .
history
After the discovery of the positive health properties of melanoidins in 2001, more attempts were made to extract these substances from foods and to clarify their structure. Since the group of substances is very inhomogeneous and polymers with masses of up to 100,000 Dalton occur, it was initially not possible to extract individual melanoidins. It was not until 2002 that pronyl lysine was isolated from the crust of mixed rye bread and its antioxidant properties were proven.
Appearance and properties
Pronyl-lysine is produced by heating a hexose such as glucose and lysine with elimination of water. First, the glucose is condensed to acetylformoin , which then reacts with lysine to form a precursor of pronyl-lysine. The carboxylic acid group of the molecule is esterified with methanol and the precursor is then converted with acetic acid to form the end product:
In laboratory tests, pronyl-lysine showed an increase in the activity of glutathione-S-transferase ( GST ) and an inhibition of NADPH-cytochrome-c-reductase in human colon cancer cell cultures . From this, the researchers derived an antioxidant and chemopreventive activity, which could also be proven in current studies on rats. The effect as a cancer inhibitor , on the other hand, is currently judged rather cautiously by reputable sources such as the Federal Institute for Risk Assessment .
See also
Individual evidence
- ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
- ↑ M. Lindenmeier, V. Faist, T. Hofmann: Structural and functional characterization of pronyl-lysine, a novel protein modification in bread crust melanoidins showing in vitro antioxidative and phase I / II enzyme modulating activity. In: Journal of agricultural and food chemistry. Volume 50, Number 24, November 2002, pp. 6997-7006, PMID 12428950 .
- ↑ Anke Förster: Quantitative study on the occurrence and metabolic transit of alimentary Maillard reaction products , TU Dresden , February 15, 2006.
- ↑ V. Somoza, E. Wenzel, M. Lindenmeier, D. Grothe, HF Erbersdobler, T. Hofmann: Influence of feeding malt, bread crust, and a pronylated protein on the activity of chemopreventive enzymes and antioxidative defense parameters in vivo. In: Journal of agricultural and food chemistry. Volume 53, Number 21, October 2005, pp. 8176-8182, doi : 10.1021 / jf0512611 , PMID 16218661 .
- ↑ BfR : Bread Crust Against Cancer ( Memento of February 2, 2007 in the Internet Archive ), opinion of December 13, 2002.