Developing analytical methods for glycyrrhizin and its major metabolite glycyrrhetic acid in the aquatic environments

• Main Authors: Yi-Ting Chen, 陳怡婷
• Other Authors: 林郁真
• Format: Others
• Language: en_US
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/77446000740473806350

碩士 === 臺灣大學 === 環境工程學研究所 === 98 === Licorice is one of common traditional Chinese medicines. Glycyrrhizin (GLY), the principle active ingredient of licorice, is the ingredient of antitussive and mucolytic-expectorant for the treatment of chronic hepatitis or allergies. GLY has also been widely used in food additives industry. After oral administration, GLY and its metabolite glycyrrhetic acid (GA) enter the aquatic environment via septic systems. The aims of this research were to: 1) develop analytical method of GLY and GA based on a solid phase extraction (SPE) procedure followed by liquid chromatography tandem mass spectroscopy and 2) investigate GLY and GA in Sindian river and two hospital effluents. In this research, the optimized SPE procedure that used Oasis MCX cartridges were pre-conditioned by rinsing with 6 mL methanol (MeOH) and 6 mL deionized water (DI water). After the conditioning step, water samples were percolated through MCX cartridges. Water samples were adjusted at pH 2 with hydrochloric acid. Then, the elute solution selected 6mL MeOH-NH4OH (95:5, v/v). Finally, the extract solutions are complete evaporated by nitrogen gas at 37 °C and reconstituted to 400 μL by MeOH-DI water (25:75, v/v). All standards were spiked at a concentration 100 ng/L into DI water and blank water samples. Recoveries ranged from 95-103% for DI water, river and hospital effluents by using the optimized SPE method. The method detection limits (MDLs) defined by signal-to-noise ratio of at least 10:1. MDLs of GLY and GA were 10 ng/L in DI water. MDLs varied between GLY and GA and were 10 ng/L and 50 ng/L for surface water, and 20 ng/L and 200 ng/L for hospital effluents, respectively. The result indicated the ubiquitous occurrence of GLY and GA in Sindian river. The detected concentration of GLY and GA ranged from 11 to 82 ng/L and 77 to 327 ng/L in Sindian river, respectively. The detected frequency of GLY and GA was 83% and 67%. The detected concentration of GLY and GA in hospital ranged from 1443 to 1750 ng/L and 226 to 7737 ng/L, respectively