During sourdough production, bacteria convert the linoleic acid in bread flour to a compound that has powerful antifungal activity. The research, which could improve the taste of bread, is published online ahead of print in the journal Applied and Environmental Microbiology.
The major benefits from the research are twofold: better tasting bread, says Gaenzle, because "preservatives can be eliminated from the recipes, and because sourdough bread has a more distinct and richer flavor compared to bread produced with yeast only;" and novel tools to control fungi in malting and plant production, via treatment of seeds with the anti-fungal fatty acids.
Genuine sourdough bread differs from ordinary bread in having an extra fermentation step, over and above yeast fermentation. This step is mediated by lactic acid bacteria, typically of the genus Lactobacillus, says Gaenzle.
In the study, "we offered linoleic acid to lactobacilli and screened for organisms producing potent antifungal activity," says Gaenzle. The investigators then fractionated the metabolites to isolate and identify compounds with antifungal activity. "The identification was a bottleneck in the research project," says Gaenzle. "In collaboration with analytical chemists, we had to develop novel methods for identifying the compounds."
L. hammesii produced substantial quantities of hydroxylated monounsaturated fatty acids which the researchers found strongly inhibited mold formation. A second antifungal fatty acid produced by cereal enzymes contributes to the antifungal activity of sourdough.
"The two compounds and their formation by cereal or microbial enzymes had been described previously, but their antifungal activity and their generation in food production was unknown," says Gaenzle. These new findings, he says, were "a step towards understanding how and why lactobacilli metabolize fatty acids. This could be useful in the long term to improve our understanding of the biology of these organisms."
A copy of the manuscript can be found online at http://bit.ly/asmtip0213a. Formal publication of the article is scheduled for the second March 2013 issue of Applied and Environmental Microbiology.
(B.A. Black, E. Zannini, J.M. Curtis, and M.G. Gaenzle, 2013. Antifungal hydroxy fatty acids produced during sourdough fermentation: microbial and enzymatic pathways, and antifungal activity in bread. Appl. Environ. Microbiol. Online ahead of print 11 January 2013. doi:10.1128/AEM.03784-12)
Applied and Environmental Microbiology is a publication of the American Society for Microbiology (ASM). The ASM is the largest single life science society, composed of over 39,000 scientists and health professionals. Its mission is to advance the microbiological sciences as a vehicle for understanding life processes and to apply and communicate this knowledge for the improvement of health and environmental and economic well-being worldwide.
Jim Sliwa | EurekAlert!
Flow of cerebrospinal fluid regulates neural stem cell division
22.05.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt
Chemists at FAU successfully demonstrate imine hydrogenation with inexpensive main group metal
22.05.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
Cardiovascular tissue engineering aims to treat heart disease with prostheses that grow and regenerate. Now, researchers from the University of Zurich, the Technical University Eindhoven and the Charité Berlin have successfully implanted regenerative heart valves, designed with the aid of computer simulations, into sheep for the first time.
Producing living tissue or organs based on human cells is one of the main research fields in regenerative medicine. Tissue engineering, which involves growing...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
22.05.2018 | Trade Fair News
22.05.2018 | Life Sciences
18.05.2018 | Power and Electrical Engineering