Carotenoids not only give carrots and red smear cheeses, such as Munster, Limburger, and Romadur, their characteristic red color, but they also protect organisms from oxidative stress.
A research team headed by Hans-Dieter Martin and Wilhelm Stahl at the University of Düsseldorf has now synthesized and characterized one of these carotenoids in the lab. As they report in the journal Angewandte Chemie, this compound is characterized by outstanding antioxidative and photoprotective properties.
Ranging in color from yellow to purple, carotenoids are pigments found throughout nature that act, among other things, as antioxidants. Antioxidants protect organisms from oxidative stress by capturing reactive oxygen species such as singlet oxygen and free radicals. Antioxidants are also added to foods, drugs, and plastics to prevent the oxidation of sensitive molecules.
Brevibacterium linens, bacteria used for the production of red smear cheeses, contain 3,3’-dihydorxyisorenieratene (DHIR), a carotenoid with a unique structure. Carotenoids are made of a long hydrocarbon chain with alternating single and double bonds. In addition, DHIR has phenolic groups, aromatic six-membered rings of carbon atoms with an OH group, at either end of the chain. Phenolic compounds are also known to be antioxidants; for example, they are present in the tannins in tea and wine.
By using a new synthetic route, the German research team was able to produce enough DHIR for the first comprehensive study of its properties. This revealed it to be an excellent antioxidant that beats other highly effective carotenoid antioxidants by a mile. In addition, its photoprotective properties are outstanding: DHIR protects cells from damage by UV radiation by absorbing UV light as well as capturing the free radicals produced by the radiation. These amazing antioxidative and photoprotective properties seem to stem from synergistic cooperation of the carotenoid and phenolic structural elements of DHIR.
When scavenging free radicals, in some cases both of the phenolic groups are first oxidized to quinoid groups. The resulting quinoid carotenoid, which the researchers were also able to synthesize and characterize, is itself also a very strong antioxidant. Interestingly, it is blue and thus broadens the color palette attainable with carotenoids.
Whether DHIR and its quinoid oxidation product can be used industrially as food and feed colorants, cosmetics, or antioxidants, is currently under investigation. These compounds may also be useful for the prevention of degenerative diseases related to free-radical damage, such as macular degeneration.
Author: Hans-Dieter Martin, Heinrich-Heine-Universität Düsseldorf (Germany), http://www.chemie.uni-duesseldorf.de/Faecher/Organische_Chemie/OC1/Martin
Title: 3,3’-Dihydroxyisorenieratene, a Natural Carotenoid with Superior Antioxidant and Photoprotective Properties
Angewandte Chemie International Edition 2009, 48, No. 2, doi: 10.1002/anie.200803668
Hans-Dieter Martin | Angewandte Chemie
‘Farming’ bacteria to boost growth in the oceans
24.10.2016 | Max-Planck-Institut für marine Mikrobiologie
Calcium Induces Chronic Lung Infections
24.10.2016 | Universität Basel
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
24.10.2016 | Earth Sciences
24.10.2016 | Life Sciences
24.10.2016 | Physics and Astronomy