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The analysis of the enthalpies of formation for polyenes up to nine ethylene units and many [C.sub.40][H.sub.56] carotenes inclusive of beta-carotene, alpha-carotene, lycopene, and prolycopene is described. The group equivalents related with isodesmic reactions give precise predictions within the test set.

The ultrafast internal conversion (IC) dynamics of aldehyde-substituted apocarotenoids (n'-apo-[beta]-caroten-n'-als with n = 4, 8 and 12) are examined in a systematic variation of conjugation length and solvent polarity by using time-resolved femtosecond transient absorption spectroscopy. In highly polar solvents, the IC to [S.sub.0] is very fast, irrespective of the conjugation length, which could be due to the stabilization of an intramolecular charge transfer (ICT) state in 12'-apo-[beta]-caroten-12'-al and 8'-apo-[beta]-caroten-8'-al.

A study demonstrates that nanoparticles of trans-beta-carotene are accessible using spinning disk processing (SDP), by varying the reaction conditions and the choice of surfactant, macrocyclic amphiphiles, sulfonato-calix[4,5,6,8] arenes, and alpha-beta-cyclodextrins. SDP ensures rapid mixing and fast kinetics, and nanoparticles of the carotene formed in the presence of the calixarenes are stable with respect to extraction of the carotene into an organic solvent, unlike in the presence of the cyclodextrins.

The quantum chemistry computations are employed to study the all-trans to mono-cis isomerizations of polyenes and two [C.sub.40][H.sub.56] carotenes, [beta]-carotene and lycopene, at the ground singlet ([S.sub.0]) and triplet ([T.sub.1]) states. The result obtained provide insight into the energy barrier which increases or decreases based on the central C=C rotational barrier.

The extracts of dried berries, Lycii fructus, used as food ingredients have a characteristic odor that gives undesirable sensory attribute in foods and this study focuses on isolating the aroma-active components by using direct solvent extraction with high vacuum transfer. Thirty-three aroma compounds were identified, which might be produced by enzymatic oxidation or oxidation of lipids and carotenes.

The laser-induced optoacoustic spectroscopy technique is employed to study the impact of the entropic changes on the charge separation process in triads, which is shown to mimic the photosynthetic charge separation. The results show that the entropy changes completely control the discussed charge separation.

A study describes the chemical composition, as well as the antioxidant activity of the seeds of different cultivars of mungbeans. Mungbeans are found to have a good antioxidant activity and hence can be a potential source of nutraceuticals and functional foods.

The transient dc photocurrent method is used to investigate the dipole moment of the charge-separated state in tetrahydrofuran and 2-methyltetrahydrofuran. The results show formation of a giant dipole with a moment in excess of 150 D, corresponding to separated charges located on the fullerene and carotene moieties of the triad.

Electron transfer (ET) reactions of carotenoids (Car), beta-carotene, canthaxanthin, and 7'-apo-7',7'-dicyano-beta-carotene imbedded in MCM-41 and Ti-MCM-41 were studied as a function of oxidation potential. Complexes were formed with beta-carotene and 7'-apo-7',7'-dicyano-beta-carotene but not with canthaxanthin.