Abstract:

A high-performance liquid chromatographic method was presented for the determination of the contents of six isoflavones. An Alltima C18 column (150 mm × 4.6 mm, 5μm), whose temperature was set at 35 ℃ was used for the chromatographic separation, which was achieved using methanol/water as mobile phase in the gradient elution mode. The detection wavelength was set at 254 nm. The injection amounts of six isoflavones over respective ranges displayed good linear relationship with the peak area and the correlation coefficients equaled or exceeded 0.9998. The average spike recoveries for six isoflavones ranged from 97% to 102%, with a RSD of less than 3%. There were significant differences in the contents of six isoflavones among soybean meals fermented by different microorganisms.

Key words: HPLC, isoflavones, quantification, fermented soybean meal