Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Don’t Compare Bananas to Pears

23.06.2010
Unique blue fluorescent chlorophyll decomposition products in banana leaves

Yellow leaves on banana plants give off a blue glow when viewed under UV light. This luminescence comes from decomposition products of chlorophyll, the substance that makes leaves green.

The decomposition products are appended with special sugar molecules in a unique fashion (hypermodified), and accumulate in ageing leaves, as Bernhard Kräutler and his team from the University of Innsbruck (Austria) report in the journal Angewandte Chemie. The researchers speculate that these long-lived chlorophyll decomposition products have physiological significance.

In other higher plants, such as apples and pears, mainly colorless, nonfluorescent chlorophyll decomposition products are found. Fluorescing decomposition products have been detected in ageing leaves before, but these have been short-lived intermediate products of chlorophyll degradation. Some time ago, Kräutler and his co-workers discovered that bananas give off a blue glow under UV light. As the bananas ripen, chlorophyll decomposition products that are colorless, but fluoresce blue, accumulate in the banana peel.

The compounds in the banana peels and leaves differ from each other, but they are both long-lived (persistent). In addition, the compounds have a structural similarity: a unique, complex ester function on a specific side chain. This group has a chemical stabilizing effect and explains the unusually long life of the fluorescing intermediates in the banana and its leaves. The leaf decomposition product, called Ma-FCC-61, is a pyrrole pigment with a previously unknown sugar unit attachment. The researchers do not rule out that this novel chlorophyll decomposition product could be a building block for previously undetected and even more complex pigments.

“When leaves of plants de-green and when fruits ripen, they develop fascinating colors,” says Kräutler. “Bright colors of fruit are believed to have evolved as valuable signals to attract frugivores, which are needed for seed dispersal. Indeed, the blue luminescence of ripe bananas may fulfill such a role,” according to Kräutler. The additional “advertisement” of fruit with colorful and possibly luminescent leaves could be a further optical signal from fruiting plants. “In any case, we need to reconsider the previous assumption that chlorophylls in ageing leaves are always disposed of by a general route leading to nonfluorescent decomposition products,” says Kräutler.

Author: Bernhard Kräutler, Universität Innsbruck (Austria), http://pc43-c726.uibk.ac.at/oci/people/en_bernhard_kraeutler.html

Title: Hypermodified Fluorescent Chlorophyll Catabolites: Source of Blue Luminescence in Senescent Leaves

Angewandte Chemie International Edition 2010, 49, No. 30, Permalink to the article: http://dx.doi.org/10.1002/anie.201000294

Bernhard Kräutler | Angewandte Chemie
Further information:
http://pressroom.angewandte.org
http://pc43-c726.uibk.ac.at/oci/people/en_bernhard_kraeutler.html

More articles from Life Sciences:

nachricht Cryo-electron microscopy achieves unprecedented resolution using new computational methods
24.03.2017 | DOE/Lawrence Berkeley National Laboratory

nachricht How cheetahs stay fit and healthy
24.03.2017 | Forschungsverbund Berlin e.V.

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>