Scientists have long assumed that bitter taste evolved as a defense mechanism to detect potentially harmful toxins in plants. The Current Biology paper provides the first direct evidence in support of this hypothesis by establishing that variants of the bitter taste receptor TAS2R38 can detect glucosinolates, a class of compounds with potentially harmful physiological actions, in natural foods.
In the study, 35 healthy adults were genotyped for the hTAS2R38 bitter taste receptor gene; the three genotypes were PAV/PAV (sensitive to the bitter-tasting chemical PTC,) AVI/AVI (insensitive), and PAV/AVI (intermediate).
Subjects then rated bitterness of various vegetables; some contained glucosinolates while others did not. Examples of the 17 glucosinolate-containing vegetables include watercress, broccoli, bok choy, kale, kohlrabi, and turnip; the 11 non-glucosinolate foods included radicchio, endive, eggplant and spinach. Subjects with the sensitive PAV/PAV form of the receptor rated the glucosinolate-containing vegetables as 60% more bitter than did subjects with the insensitive (AVI/AVI) form. The other vegetables were rated equally bitter by the two groups, demonstrating that variations in the hTAS2R38 gene affect bitter perception specifically of foods containing glucosinolate toxins.
Together, the findings provide a complete picture describing individual differences in responses to actual foods at multiple levels: evolutionary, genetic, receptor, and perceptual. "The sense of taste enables us to detect bitter toxins within foods, and genetically-based differences in our bitter taste receptors affect how we each perceive foods containing a particular set of toxins," summarizes Breslin.
Breslin notes, "The contents of the veggies are a double-edged sword, depending upon the physiological context of the individual eating them. Most people in industrialized cultures can and should enjoy these foods. In addition to providing essential nutrients and vitamins, many are reported to have anti-cancer properties."
Lead author Mari Sandell comments on additional nutritional and practical implications of the study, "Taste has a great impact on food acceptability and choice. A comprehensive understanding how food components contribute to taste is necessary to develop modern tools for both nutritional counseling and food development."
Paul Breslin | EurekAlert!
More genes are active in high-performance maize
19.01.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn
How plants see light
19.01.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau
On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.
We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
19.01.2018 | Materials Sciences
19.01.2018 | Health and Medicine
19.01.2018 | Physics and Astronomy