Determination of Selenium Species in Cordyceps militaris by High-performance Liquid Chromatography Coupled to Hydride Generation Atomic Fluorescence Spectrometry

ABSTRACT

The purpose of this work is to develop a high-efficiency extraction method for determining the selenium species in Cordyceps militaris. Six extraction solutions, including hot water, HCl, methanol–water, ammonium acetate, protease XIV, and protease K, combined with ultrasound-assisted extraction, were utilized in the measurements. The selenium species in the extracts were separated and characterized by high-performance liquid chromatography. Their concentrations were subsequently determined by hydride generation atomic fluorescence spectrometry. The 25 mM ammonium acetate was selected as the extraction solution due to its advantages in cost and efficiency. Validation was performed, and the selenium species recoveries were 69–97% for selenocystine, selenite, selenomethionine, and selenate with good linearity and precision. The major selenium species in C. militaris were selenocystine and selenomethionine that accounted for almost 73.1 ± 1.6% of the total selenium.

KEYWORDS:

• Atomic fluorescence spectrometry
• Cordyceps militaris
• high-performance liquid chromatography
• hydride generation
• selenium species

Additional information

Funding

This research was supported by National Natural Science Foundation of China (31470531) and the Special Fund for Agro-scientific Research in the Public Interest (201303106).