It is perhaps surprising that fruits with blue pigments are less common, since many visually guided fruit eaters have eyes highly adapted to blue sensitivity. However, some fruits do not contain blue pigment. In a new study, scientists from the University of Bristol and elsewhere investigated dark fruits with wax blooms, such as blueberries, plums and juniper cones, and found that structural color mechanisms are involved in their appearance. Did.
The structural color of the wax bloom gives the fruit a blue appearance across a wide range of accessions. (A) Undamaged highbush blueberries growing on the plant. (B) Blueberry (i) unmodified wax, (ii) mechanical wax removal, (iii) chloroform wax removal, (iv) surface application of (approximately) index-matched oil, (v) surface application of water; (vi) peeling off the outer skin to expose the pulp; (vii) the underside of the peeled skin; (C) Transmission light microscopy of a blueberry peel peeled from the inner edge showing red pigmentation of epidermal cells. Scale bar – 200 μm. (D) (i and ii) Plum selection (Plum) Fruits with different cell pigmentation, (i) with wax intact and (ii) with wax removed.Image credit: Middleton other., doi: 10.1126/sciadv.adk4219.
“You can't 'extract' the blue color from blueberries by crushing them, because blueberries are not present in the highly pigmented juice that can be squeezed from the fruit,” said lead author Dr Rocks Middleton, a researcher at the University of Bristol.
“That's why I knew there had to be something strange about this color.”
“So we removed the wax and recrystallized it on the card. In doing so, we were able to create a completely new blue UV coating.”
This ultra-thin colorant is about 2 microns thick, has a low reflectance, but looks blue and reflects UV well, potentially paving the way for new colorant methods.
“This shows that nature has evolved to use a very neat trick: an extremely thin layer of a vital colorant,” Dr Middleton said.
Most plants are covered with a thin layer of wax, which has multiple functions, many of which are still unknown to scientists.
They know that it is highly effective as a hydrophobic, self-cleaning coating, but only now have they realized how important this structure is for visible coloration.
Now Dr. Middleton and colleagues plan to look at easier ways to recreate and apply the coating.
This could lead to the development of more sustainable, biocompatible, and even edible UV- and blue-reflecting paints.
Additionally, these coatings may have multiple functions similar to natural biological coatings that protect plants.
“It was really interesting to discover that there was an unknown coloration mechanism just beneath the surface of the popular fruit that we grow and eat all the time,” Dr Middleton said.
“It was even more exciting to be able to recreate that color by taking wax and creating a new blue coating that no one had ever seen before.”
“Our dream is to incorporate all the functionality of this natural wax into a man-made material.”
of result It was published in the magazine scientific progress.
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Rocks Middleton other. 2024. Self-organized disordered structural colors from fruit wax blooms. scientific progress 10(6); doi: 10.1126/sciadv.adk4219
Source: www.sci.news
