Determination of 20 Free Amino Acids in Asparagus Tin by High-Performance Liquid Chromatographic Method after Pre-Column
- PDF / 188,113 Bytes
- 7 Pages / 595.276 x 790.866 pts Page_size
- 48 Downloads / 209 Views
Determination of 20 Free Amino Acids in Asparagus Tin by High-Performance Liquid Chromatographic Method after Pre-Column Derivatization Weihua Li & Meijun Hou & Yongsong Cao & Huan Song & Tianyu Shi & Xiwu Gao & Daning Wang
Received: 3 November 2010 / Accepted: 10 January 2011 / Published online: 28 January 2011 # Springer Science+Business Media, LLC 2011
Abstract A novel method was studied for determination of 20 free amino acids in asparagus tin by high-performance liquid chromatography with pre-column derivatization. Derivatization of the samples was performed with 4chloro-3,5-dinitrobenzotrifluoride (CNBF), and the SPE cartridge was used for purification and enrichment of the analytes. The derivatization conditions and the influence of elution composition on the separation were investigated. The reaction of amino acids with CNBF was completed in pH 9.0 borate buffer. The separation of amino acids was achieved at room temperature within 60 min by gradient elution mode with triethylamine in mobile phase, and the flow rate is 0.32 mL min−1 constantly. The method correlation coefficient was from 0.9975 to 1.0000 in concentrations ranging from 20 to 2000 μmol L−1, except asparagine (from 100 to 10000 μmol L−1). The detection limits of amino acids were from 1.2 to 6.0 μmol L−1, with a signal-to-noise ratio of three times. The calculated recoveries of the proposed method were from 81.4% to 109.4%, and relative standard deviations were 0.48–3.94% in application to the quantitative determination of free amino acids in asparagus tin samples. The present method is reliable and sensitive that allows fast analysis of free amino W. Li : Y. Cao : T. Shi : X. Gao : D. Wang (*) College of Agriculture and Biotechnology, China Agricultural University, No. 2 Yuanmingyuan West Road, Beijing 100193, China e-mail: [email protected] M. Hou : H. Song Technology Center, Shanxi Entry-Exit Inspection and Quarantine Bureau, NO. 8 Yi fen Street, Taiyuan, Shanxi 030024, People’s Republic of China
acids in asparagus tin, which makes it suitable for further study of free amino acids in other asparagus foods. Keywords Free amino acid . Asparagus tin . Highperformance liquid chromatography . Pre-column derivatization
Introduction Asparagus (Asparagus officinalis L) is a herbaceous perennial plant. For its abundant amino acid contents, asparagus is a top-grade vegetable and healthy food, which is recommended as one of the top ten vegetables in the world and enjoys reputation as the “king of vegetables”. Asparagus tin is achieved by adding weak acid juice to asparagus in tins and processing in high pressure and temperature. There is abundance of free amino acids, especially plenty of asparagine, in asparagus tin, which has a high nutritional value. The separation and determination of amino acids by reversed-phase liquid chromatography (RP-HPLC) were still active fields which were summarized by Blau and King (1977) and Knapp (1979). In recent years, separation of the derivatives by pre-column derivatization and RP-HPLC has been widely used (
Data Loading...
