Analytical Sciences


Abstract − Analytical Sciences, 20(2), 329 (2004).

Determination of Biologically Active Substances in Roasted Coffees Using a Diode-Array HPLC System
Mayumi MINAMISAWA,*  Shoichiro YOSHIDA,** and Nobuharu TAKAI***
*Tokyo College of Medico-Pharmaco Technology, 6-5-12 Higashikasai, Edogawa-ku, Tokyo 134-8530, Japan
**Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
***Department of Biotechnology, College of Science and Engineering, Tokyo Denki University, Hatoyama, Hiki-gun, Saitama 350-0394, Japan
We studied the simultaneous quantitative analysis of biologically active substances, such as nicotinic acid, trigonelline, caffeine, qunolinic acid and tannic acid and pyrogallic acid, in several roasted coffees by an HPLC/diode-array system with a home-made sol-gel and ODS-2 columns. A simple method for simultaneous quantitative analysis of biologically active substances in the coffee brew became feasible by an HPLC/diode-array system with a sol-gel column at a single wavelength of 210 nm. The most efficient condition of the Rs value was above 1.05 when two sol-gel columns were connected. In addition, the elution behavior of nicotinic acid in brew extracted from commercially available coffee beans suggests the thermal decomposition process during roasting, and indicated the maximum value for full city roasted coffee.