Abstract
All-trans β-carotene in various solvents was irradiated with W-, Xe-, Hg-lamp or sunlight and the decreasing ratio of the light absorbance at λ_<mxa> was preliminary estimated. Irradiation products of β-carotene in n-hexane, acetone, chloroform or carbon tetrachloride were evaluated by column chromatography and were determined spectrometrically. They were identified as retro-dehydrocarotenes (all-trans, neo-A, D and F), mutatochromes (all-trans and neo-A) and β-carotenes (recovered all-trans, neo-U, B and E). Experimental data obtained under various conditions indicate that β-carotene in the above solvents does not seem to be epoxidized by short insolation.
