Sugar and cyclitol determination in vegetables by HPLC using postcolumn fluorescent derivatization.

摘要

Non-reducing sugars such as sucrose, raffinose, myo-inositol, pinitol and galactinol were separated on a polyamine-bonded polymer gel (NH2 type) column using acetonitrile/water (3:1, v/v) as the mobile phase. Sugars in the eluate were detected by periodate oxidation and subsequent derivation with guanidine to fluorescent compounds. Detection limits were: sucrose 2.5, D-glucose 2.5 and pinitol 4 ng. In comparison with the conventional method using refractive index detection, this highly sensitive method was quicker and more accurate when determining sugar contents in immature soybean seeds, sweet corn kernels and chinese mustard leaves; smaller volumes of extracts were injected onto the column and the column life was longer.