Enantioseparation of Isoxanthohumol in Beer by Hydroxypropyl-γ-cyclodextrin-Modified Micellar Electrokinetic Chromatography

Kodama, Shuji; Yamamoto, Atsushi; Satô, Atsushi; Suzuki, Kentaro; Yamashita, Tomohisa; Kemmei, Tomoko; Taga, Atsushi; Hayakawa, Kazuichi

doi:10.1021/jf0710478

Cited by 15 publications

(17 citation statements)

References 38 publications

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“…In hop cones, the most abundant prenylated chalcone is xanthohumol, which accounts for 80–90% of the prenylated flavonoids in hop. During the brewing process of beer, xanthohumol is converted into the corresponding isomeric prenylflavanone isoxanthohumol 28. A hydroxypropyl‐γ‐CD‐modified MEKC method has been proposed for the chiral resolution of isoxanthohumol enantiomers in beer samples.…”

Section: Phenolic Compoundsmentioning

confidence: 99%

Synthesis of 5‐(1,2,3‐Triazol‐4‐yl)‐2′‐deoxyuridines by a Click Chemistry Approach: Stacking of Triazoles in the Major Groove Gives Increased Nucleic Acid Duplex Stability

et al. 2007

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A general protocol for converting alkyl and aryl halides into azides and for converting these in situ into 1,4-disubstituted triazoles was applied with 5-ethynyl-2'-deoxyuridine. This afforded three modified 2'-deoxyuridine analogues with either unsubstituted or 1-phenyl-/1-benzyl-substituted triazoles in their 5-positions. Modelling demonstrates coplanarity of the two heteroaromatic rings, and UV spectroscopy showed the uracil pK(a) values to be almost unchanged. The three nucleosides were introduced into nonamer oligonucleotides by phosphoramidite chemistry. The heteroaromatic triazoles became positioned in the major grooves of the short dsDNA and DNA-RNA duplexes. While single modifications led to decreased duplex stability, the stacking of four consecutive modifications led to enhanced duplex stability, especially for DNA-RNA duplexes. The duplex structures were studied by CD spectroscopy and molecular dynamics simulations, which supported the conjecture that the duplex stabilizing effect is due to efficient stacking of the heteroaromatic triazoles.

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Section: Phenolic Compoundsmentioning

confidence: 99%

Synthesis of 5‐(1,2,3‐Triazol‐4‐yl)‐2′‐deoxyuridines by a Click Chemistry Approach: Stacking of Triazoles in the Major Groove Gives Increased Nucleic Acid Duplex Stability

et al. 2007

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“…The wide use of UV detection was also true for food and food contaminants analyses 85, 177, 190, 196–287. However, increasing also were those exploiting CE‐MS 141, 143–145, 146, 148, 288–303.…”

Section: Detection Strategiesmentioning

confidence: 99%

“…Using CZE with β‐CD, the method offered high separation efficiency, short analysis time (<20 mins), small sample consumption, and good repeatability. Employing a hydroxypropyl‐γ‐CD‐modified MEKC, the chiral resolution of isoxanthohumol in beer samples has been performed 282. The racemization of isoxanthohumol in beer was also attributed to its enantiomers being easily interconverted.…”

Section: Chiral Separationsmentioning

confidence: 99%

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Capillary electrophoresis of natural products: Highlights of the last five years (2006–2010)

2011

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An extensive search of the published research and review articles indicated a growing number of works that employed electroseparation techniques. Capillary zone electrophoresis (CZE) and electrokinetic chromatography (EKC), in particular, were found to be popular for the analyses of natural products. This review outlines the important developments in this field over the years, especially during the 2006-2010 period. An overview of the natural product applications such as pharmaceuticals/herbal products, fingerprinting and quality control, food and food contaminants, and toxicological compounds of interest to forensics were presented. Important areas of detection strategies, microchips, sample preconcentration, and chiral separations were also discussed. Hence, quick information was provided on the researches already undertaken and the possibilities of unexplored areas. In addition, fundamental concepts for the understanding of CZE and EKC and their suitability for natural products analyses were briefly discussed.

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“…Then, Martinez and Davies () also studied the enantiospecific pharmacokinetics of IX in rats using LC–MS with a Chiralcel OD‐RH column and found that ( S )‐8‐PN was excreted in the urine more than ( R )‐8‐PN. We also studied enantiomeric separation of IX (Kodama et al, ) and 8‐PN (Kodama et al, ) by hydroxypropyl‐ γ ‐cyclodextrin‐modified micellar electrokinetic chromatography. In this study, we determined XN, IX and 8‐PN in beer, hop pellet and hop samples by reversed‐phase HPLC method and also analyzed enantiomers of IX and 8‐PN by HPLC with chiral columns.…”

Section: Introductionmentioning

confidence: 99%

Chiral separation of isoxanthohumol and 8‐prenylnaringenin in beer, hop pellets and hops by HPLC with chiral columns

Moriya

Tanaka

Iida

et al. 2018

Biomedical Chromatography

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Xanthohumol, isoxanthohumol, and 8-prenylnaringenin in beer, hop and hop pellet samples were analyzed by HPLC using an InertSustain phenyl column and the mobile phase containing 40% methanol and 12% 2-propanol. Fractions of isoxanthohumol and 8-prenylnaringenin obtained by the above HPLC were separately collected. Isoxanthohumol and 8-prenylnaringenin were enantioseparated by HPLC using a Chiralcel OD-H column with a mobile phase composed of hexane-ethanol (90:10, v/v) and a Chiralpak AD-RH column with a mobile phase composed of methanol-2-propanol-water (40:20:40, v/v/v), respectively. Isoxanthohumol and 8-prenylnaringenin from beer, hop and hop pellet samples were found to be present in a racemic mixture. This can be explained by the fact that the two analytes were produced by a nonenzymatic process. The effects of boiling conditions on the conversion of xanthohumol into isoxanthohumol were also studied. A higher concentration of ethanol in heating solvent resulted in a decrease in the conversion ratio and the conversion was stopped by addition of ethanol at >50% (v/v). The isomerization was significantly affected pH (2-10) and the boiling medium at pH 5 was minimum for the conversion. Therefore, it was suggested that xanthohumol was relatively difficult to convert to isoxanthohumol in wort (pH 5-5.5) during boiling.

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Enantioseparation of Isoxanthohumol in Beer by Hydroxypropyl-γ-cyclodextrin-Modified Micellar Electrokinetic Chromatography

Cited by 15 publications

References 38 publications

Synthesis of 5‐(1,2,3‐Triazol‐4‐yl)‐2′‐deoxyuridines by a Click Chemistry Approach: Stacking of Triazoles in the Major Groove Gives Increased Nucleic Acid Duplex Stability

Synthesis of 5‐(1,2,3‐Triazol‐4‐yl)‐2′‐deoxyuridines by a Click Chemistry Approach: Stacking of Triazoles in the Major Groove Gives Increased Nucleic Acid Duplex Stability

Capillary electrophoresis of natural products: Highlights of the last five years (2006–2010)

Chiral separation of isoxanthohumol and 8‐prenylnaringenin in beer, hop pellets and hops by HPLC with chiral columns

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