Takehara Munenori, Kuwa Takahiro, Inoue Yoshinori, Kitamura Chitoshi, Honda Masaki
Department of Materials Science, The University of Shiga Prefecture, Hassaka, Hikone 522-8533, Japan.
Department of Materials Science, The University of Shiga Prefecture, Hassaka, Hikone 522-8533, Japan.
Biochem Biophys Res Commun. 2015 Nov 6;467(1):58-62. doi: 10.1016/j.bbrc.2015.09.122. Epub 2015 Sep 28.
(15Z)-Lycopene was prepared by thermal isomerization of (all-E)-lycopene derived from tomatoes, and isolated by using a series of chromatographies. The fine red crystalline powder of (15Z)-lycopene was obtained from 556 mg of (all-E)-lycopene with a yield of 0.6 mg (purity: reversed-phase HPLC, 97.2%; normal-phase HPLC, ≥99.9%), and (1)H and (13)C NMR spectra of the isomer were fully assigned. More refined computational analyses that considered differences in the energy levels of the conformers involved in isomerization have also determined the stabilities of (15Z)-lycopene and other geometric isomers, along with the activation energies during isomerization from the all-E form. The fine control of conditions for HPLC separation and an advanced theoretical insight into geometric isomerization have led to the discovery of the 15Z-isomer generated from a natural source.
(15Z)-番茄红素是由番茄中提取的（全反式）-番茄红素经热异构化制备而成，并通过一系列色谱法进行分离。从556毫克（全反式）-番茄红素中获得了0.6毫克（纯度：反相高效液相色谱法为97.2%；正相高效液相色谱法≥99.9%）的（15Z）-番茄红素精细红色结晶粉末，并对该异构体的(1)H和(13)C核磁共振谱进行了全归属。考虑异构化过程中构象体能量水平差异的更精细计算分析，也确定了(15Z)-番茄红素和其他几何异构体的稳定性，以及从全反式异构体异构化过程中的活化能。高效液相色谱分离条件的精细控制以及对几何异构化的深入理论洞察，促成了从天然来源生成的15Z-异构体的发现。
