title: Unique spectroscopic properties of synthetic 15-cis beta-carotene, an important compound in photosynthesis, and a medicine for photoprotective function.
abstract: The (1(1)B(u)+) energy of synthetic 15-cis beta-carotene exhibits a linear dependence on (n(2)-1)/(n(2)+2) in non-polar and polar solvents; in this it is similar to (that of) all-trans beta-carotene. The point of intersection is at (n(2)-1)/(n(2)+2) = 0.3 for both isomers. The microenvironment of 15-cis beta-carotene in the Photosystem II reaction center was established as having a mean refractive index 1.473. Persistent spectral hole burning with a very broad (approximately 30 nm) hole observed around 500 nm (corresponding to an extremely short excited lifetime tau approximately 9 fs) indicates that 15-cis beta-carotene has/displays very efficient photoprotective quenching.
authors.affiliation: Faculty of Technical Physics, Poznań University of Technology, 60-965 Poznań, Nieszawska 13 a, Poland. bialek@phys.put.poznan.pl
authors.forename: Grazyna Ewa
authors.initials: GE
authors.lastname: Białek-Bylka
authors.forename: Beata
authors.initials: B
authors.lastname: Jazurek
authors.forename: Roman
authors.initials: R
authors.lastname: Dedic
authors.forename: Jan
authors.initials: J
authors.lastname: Hala
authors.forename: Andrzej
authors.initials: A
authors.lastname: Skrzypczak
mesh_terms: D003080:Cold Temperature; D006586:Hexanes / Q000378:metabolism; D015394:Molecular Structure; D010788:Photosynthesis; D045332:Photosystem II Protein Complex / Q000737:chemistry; D011837:Radiation-Protective Agents / Q000378:metabolism*; D013057:Spectrum Analysis / Q000379:methods*; D019207:beta Carotene / Q000032:analysis* / Q000737:chemistry
chemical_list: D006586:Hexanes; D045332:Photosystem II Protein Complex; D011837:Radiation-Protective Agents; D019207:beta Carotene