A chemical substance produced by corals – palithin is ideal for the production of creams from the so-called UV filter – say scientists from Spain. Their research is described in Physical Chemistry Chemical Physics.
A substance with strong photoactive properties, it enables the transformation of dangerous UV radiation contained in sunlight into harmless thermal energy. The transformation process takes place without the participation of harmful reactive oxygen compounds.
Long-term exposure to strong ultraviolet (UV) radiation causes many negative side effects in living organisms, including humans. Part of the UV radiation is absorbed by the Earth’s atmosphere (the ozone layer), but the dose that reaches the surface of our planet is still not indifferent to the proper development of plants and animals. For this reason, nature has invented many defense mechanisms against UV radiation, including photoactive chemicals.
Scientists from the University of La Rioja (Spain) looked at one of these substances – palitin – which is naturally produced by corals in order to protect tissues from the destructive effects of UV radiation. The conducted experiments were aimed at understanding the mechanism responsible for the conversion of ultraviolet radiation into thermal energy by the palitin.
Model studies, using advanced computer simulation, made it possible to discover the mysterious properties of palithin, and more specifically energy transformation, without producing any reactive intermediates or highly reactive reaction by-products (e.g. oxygen radicals).
From the physicochemical point of view, palitin most strongly absorbs solar radiation with a wavelength of 320 nm.
It turned out that the palitin molecule – which belongs to the group of amino acids – undergoes spatial reorganization after receiving the appropriate dose of UV radiation, generating additional bonds inside the molecule. As a result of such internal transformation, the absorbed light energy is converted into thermal energy without the participation of highly reactive oxygen species or other substances that may adversely affect living cells.
According to scientists, the newly discovered characteristics of palithin suggest that this molecule will soon be used by cosmetic companies as a safe UV sunscreen filter.
Already today, palithin meets all the criteria of a good UV protector, because it effectively absorbs ultraviolet radiation, efficiently transforming it into heat energy, without generating hazardous compounds that can damage the skin. Its advantage is also its natural origin. (PAP)