A comprehensive HPLC analytical system for the identification and quantification of hexoses that employs 2-aminobenzamide coupling.
Rare sugars are defined as monosaccharides with extremely low natural abundances. Their natural distributions and biological functions remain to be clarified. To establish a robust analytical system that can separate, identify and quantify rare sugars, 12 d-hexoses-including five rare aldohexoses and three rare ketohexoses-were labelled with 2-aminobenzamide (2-AB), and the fluorescently tagged monosaccharides were separated by high-performance liquid chromatography (HPLC). Because the ketohexoses were much less reactive than were the aldohexoses, the reaction conditions were optimized to achieve the maximum yields (>75%) for both aldohexoses and ketohexoses. The calibration curve determined for the rare ketohexose, d-psicose (Psi), was linear between 1 pmol and 1 micromol and had a correlation coefficient of 0.9999. Using the developed method, the psicose content in a leaf of Itea virginica, in which the presence of psicose has previously been reported, was found to be 2.7 mg psicose/g leaf. The result proved feasibility of the method even for natural products. Because the system is a comprehensive tool, it should help answer questions concerning the biosyntheses and functions of rare hexose sugars.
Hasehira
Kayo
K
Department of Functional Glycomics, Life Science Research Center, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, Japan.
Nakakita
Shin-Ichi
S
Miyanishi
Nobumitsu
N
Sumiyoshi
Wataru
W
Hayashi
Shie
S
Takegawa
Kaoru
K
Hirabayashi
Jun
J
D053000:Analytic Sample Preparation Methods; D002138:Calibration; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D056148:Chromatography, Reverse-Phase; D005632:Fructose / Q000032:analysis; D006601:Hexoses / Q000032:analysis* / Q000737:chemistry* / Q000302:isolation & purification; D006358:Hot Temperature; D057230:Limit of Detection; D009994:Osmolar Concentration; D018515:Plant Leaves / Q000737:chemistry; D015203:Reproducibility of Results; D031995:Saxifragaceae / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013997:Time Factors; D062367:ortho-Aminobenzoates / Q000737:chemistry*
D006601:Hexoses; D062367:ortho-Aminobenzoates; C003243:psicose; D005632:Fructose; C000219:anthranilamide