Supplementary and revised assignment of the peaks of the 7,9-, 9,9′-, 13,13′-, 9,13′-di-cis and 9,9′,13-tri-cis isomers of β-carotene in high-performance liquid chromatography using a column of calcium hydroxide

Koyama, Yasushi; Hosomi, Mitsunori; Miyata, Akio; Hashimoto, Hideki; Reames, Seth A.; Nagayama, Kuniaki; Kato-Jippo, Toshiyo; Shimamura, Toshio

doi:10.1016/s0021-9673(01)83855-3

Cited by 42 publications

(20 citation statements)

References 7 publications

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“…heating in vacuo the all-trans crystals to the melting point, 183 ЊC, and (d) by I 2 -sensitized photoisomerization of the all-trans isomer in n-hexane. Assignment of each peak in the elution profiles (c) and (d) is based on structural determination by 1 H NMR spectroscopy 16,19,22 and also on the results of thermal-and photo-isomerization. 20 I 2sensitized photo-isomerization produces only the methylatedcis (9-cis and 13-cis) configurations, and thermal isomerization produces additionally a pair of unmethylated-cis (7-cis and 15cis) configurations.…”

Section: Resultsmentioning

confidence: 99%

Unique properties of the 11-cis and 11,11′-di-cis isomers of β-carotene as revealed by electronic absorption, resonance Raman and 1H and 13C NMR spectroscopy and by HPLC analysis of their thermal isomerization

Hu¹,

Hashimoto²,

Moine³

et al. 1997

J. Chem. Soc., Perkin Trans. 2

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Section: Resultsmentioning

confidence: 99%

Unique properties of the 11-cis and 11,11′-di-cis isomers of β-carotene as revealed by electronic absorption, resonance Raman and 1H and 13C NMR spectroscopy and by HPLC analysis of their thermal isomerization

Hu¹,

Hashimoto²,

Moine³

et al. 1997

J. Chem. Soc., Perkin Trans. 2

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“…Even in the acetone extract, the broad elution profile of component 2 (Figure la), which is assigned to the single component of all-trans-~-carotene, indicates that the 15-cis to alltrans isomerization is taking place even in the HPLC system during the adsorption/desorption processes in the column and possibly during the transfer in the tubings as well; the resolution of each isomer in the elution profile for a mixture of stable isomers was much higher under similar HPLC conditions (Koyama et al 1988). Further, another isomer (possibly 13-cis) was found as an intermediate in the process of 15-cis to all-trans isomerization when the extract was left to stand in the dark (data not shown).…”

mentioning

confidence: 98%

15-Cis-?-carotene found in the reaction center of spinach Photosystem I

et al. 1996

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β-Carotene was extracted from spinach Photosystem I reaction centers (one consisting of the Psa A, B, C, D and E subunits and the other consisting of the Psa A and B subunits alone), and the extract was subjected to high-pressure liquid chromatography using an apparatus equipped with a two-dimensional diode-array detector; all the procedures were performed at ≈ 4 °C in complete darkness. Both 15-cis and all-trans-β-carotene were identified in the extract by means of electronic absorption spectroscopy. Thus, universal presence of 15-cis carotenoid in the reaction centers of purple photosynthetic bacteria and of spinach Photosystem I and Photosystem II has been shown.

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“…Peak assignment of the different isomers were done using the relative relationship between the max‐peak absorbance at 454 nm and the cis ‐peak absorbance at 340 nm as described by Koyama and co‐workers . Quantification was done using a 5‐point standard curve at 421 nm.…”

Section: Methodsmentioning

confidence: 99%

Physical State of β‐Carotene at High Concentrations in a Solid Triglyceride Matrix

Schjoerring-Thyssen

Olsen

Koehler

et al. 2019

Euro J Lipid Sci & Tech

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The highly hydrophobic -carotene is often distributed or dissolved in triglycerides to enhance either nutritional or coloring effects. This study aims at elucidating the physical state of -carotene that at high concentrations are mixed into a solid high-melting tri-glyceride matrix by dissolution at high temperatures (165°C) in the melted triglyceride. Extensive isomerization of -carotene is observed by HPLC after melting crystalline all-trans -carotene and in the solid mixtures of -carotene and fully hydrogenated sunflower oil. Crystalline triglyceride is found in the mixed samples by XRPD analysis whereas no signs of crystalline lattice structures of -carotene are detected. DSC thermograms show only the melting and recrystallization events of triglycerides, which are affected by the presence of -carotene. Severe line broadening is observed in the 13 C CP/MAS NMR spectra of the -carotene-triglyceride mixtures when compared to crystalline -carotene, demonstrating the lack of long-range order of the carotene. Altogether, the results demonstrate that -carotene is present as an amorphous mixture of transand cis-isomers dispersed into a structure of crystalline triglyceride in the solid carotene-triglyceride mixtures. Practical applications: The amorphous structure of transand cis-isomers in solid formulations of -carotene-triglyceride mixtures will strongly affect their functional properties related to nutrition and color as food ingredients.

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Supplementary and revised assignment of the peaks of the 7,9-, 9,9′-, 13,13′-, 9,13′-di-cis and 9,9′,13-tri-cis isomers of β-carotene in high-performance liquid chromatography using a column of calcium hydroxide

Cited by 42 publications

References 7 publications

Unique properties of the 11-cis and 11,11′-di-cis isomers of β-carotene as revealed by electronic absorption, resonance Raman and 1H and 13C NMR spectroscopy and by HPLC analysis of their thermal isomerization

Unique properties of the 11-cis and 11,11′-di-cis isomers of β-carotene as revealed by electronic absorption, resonance Raman and 1H and 13C NMR spectroscopy and by HPLC analysis of their thermal isomerization

15-Cis-?-carotene found in the reaction center of spinach Photosystem I

Physical State of β‐Carotene at High Concentrations in a Solid Triglyceride Matrix

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