Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A substance from bacteria can lead to allergy-free sunscreen

25.10.2011
As the realisation that radiation emitted by the sun can give rise to skin cancer has increased, so also has the use of sunscreen creams.

These creams, however, can give rise to contact allergy when exposed to the sun, and this has led to an increasing incidence of skin allergy. Scientists at the University of Gothenburg and Chalmers University of Technology are leading the hunt for a natural UV filter that does not have undesired effects.

“Unfortunately, several of the chemical UV filters used in sunscreens cause contact allergy, either of themselves or when they are exposed to sunlight. We have therefore studied a UV filter, scytonemin, that is found in certain bacteria. We have managed to produce this substance artificially in the laboratory”, says Isabella Karlsson, research student in the Department of Chemistry at the University of Gothenburg.

Sunlight contains two types of UV radiation. The type known as “UVA” penetrates deeply into the skin and causes the pigment that we already have to darken. UVA, however, also causes the skin to age prematurely. The most common chemical UVA filter on the market is 4-tert-butyl-4'-methoxy dibenzoylmethane, BM-DBM, which is known to cause photocontact allergy when it reacts on the skin.
Isabella Karlsson has shown that BM-DBM breaks down in UV light to form several different products. One of these, a group of substances known as “arylglyoxals”, proved to be very potent contact allergens.

Isabella Karlsson also describes in her thesis studies of a relatively new UV filter, octocrylene. The popularity of octocrylene has increased a great deal since it is not broken down by sunlight, and it stabilises other substances such as, for example, BM-DBM. However, several reports of allergic reactions to octocrylene have appeared in recent years. Clinical studies and laboratory experiments have suggested that octocrylene can cause contact allergy, both of itself and when it is exposed to sunlight. Many patients who reacted by developing photocontact allergy to octocrylene developed photocontact allergy also to the drug ketoprofen.

“We tested 172 patients with suspected skin reactions to sunscreen creams and/or the drug ketoprofen in one of our studies. It turned out that 23 of these patients reacted to the UV filter octocrylene. Five of them were diagnosed with contact allergy and the other 18 with photocontact allergy.”

So Isabella Karlsson is placing her hopes onto the natural product scytonemin. She has managed to produce this substance artificially, in collaboration with Chalmers University of Technology. Scytonemin is produced by certain cyanobacteria that live in habitats exposed to very strong sunlight. Scytonemin absorbs UV light and thus protects the bacteria from being damaged by the sun’s radiation. More research will be required, however, before it can be added to sunscreen creams.

The thesis Chemical and Dermatological Aspects of UV-absorbing Compounds has been successfully defended at a disputation held at the University of Gothenburg.

For more information, please contact: Isabella Karlsson
Tel: +46 31 786 9108
Mobile: +47 70 732 4737
Email: isabella.karlsson@chem.gu.se
Bibliographic data:
Title: Oxidative Coupling as a Biomimetic Approach to the Synthesis of Scytonemin. ´
Authiors: Andreas Ekebergh, Isabella Karlsson, Rudi Mete, Ye Pan, Anna Börje, and Jerker Mårtensson.
Journal: Organic Letters 13, 4458-4461 (2011).
Link to article: http://pubs.acs.org/doi/abs/10.1021/ol201812n
Title: Clinical and Experimental Studies of Octocrylene’s Allergenic Potency
Authiors: Isabella Karlsson, Katrien Vanden Broecke, Jerker Mårtensson, An Goossens, and Anna Börje.

Journal: Contact Dermatitis 64, 343-352 (2011)

Link to article: http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0536.2011.01899.x/abstract;jsessionid=2B2C2791AFA46405D5B7E647B87FF545.d04t04

Helena Aaberg | idw
Further information:
http://hdl.handle.net/2077/26665
http://www.gu.se

More articles from Life Sciences:

nachricht Zap! Graphene is bad news for bacteria
23.05.2017 | Rice University

nachricht Discovery of an alga's 'dictionary of genes' could lead to advances in biofuels, medicine
23.05.2017 | University of California - Los Angeles

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

Im Focus: Bacteria harness the lotus effect to protect themselves

Biofilms: Researchers find the causes of water-repelling properties

Dental plaque and the viscous brown slime in drainpipes are two familiar examples of bacterial biofilms. Removing such bacterial depositions from surfaces is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

Innovation 4.0: Shaping a humane fourth industrial revolution

17.05.2017 | Event News

 
Latest News

Scientists propose synestia, a new type of planetary object

23.05.2017 | Physics and Astronomy

Zap! Graphene is bad news for bacteria

23.05.2017 | Life Sciences

Medical gamma-ray camera is now palm-sized

23.05.2017 | Medical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>