Premium
Chiral separation of isoxanthohumol and 8‐prenylnaringenin in beer, hop pellets and hops by HPLC with chiral columns
Author(s) -
Moriya Hyuga,
Tanaka Sohei,
Iida Yukari,
Kitagawa Satomi,
Aizawa Senichi,
Taga Atsushi,
Terashima Hiroyuki,
Yamamoto Atsushi,
Kodama Shuji
Publication year - 2018
Publication title -
biomedical chromatography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.4
H-Index - 65
eISSN - 1099-0801
pISSN - 0269-3879
DOI - 10.1002/bmc.4289
Subject(s) - xanthohumol , chemistry , hop (telecommunications) , chromatography , high performance liquid chromatography , methanol , boiling , solvent , organic chemistry , computer network , computer science
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.