Title : Determination of caffeine and hydrogen peroxide antioxidant activity of raw and roasted coffee beans around Habru woreda, Ethiopia using UV-Vis spectroscopy
Abstract:
Coffee is one of the most popular beverages that are widely used around the world. Ethiopia which is a motherland of Arabica coffee has grown a genetic diversity of coffee with different physical and chemical properties. It is a complex chemical mixture consisting of many bioactive compounds that have antioxidant and radical scavenging activity naturally. Caffeine is considered the most active component in coffee that acts as a mild psychoactive stimulant drug. The aqueous and organic phases of extraction are commonly used to separating and quantifying caffeine using UV-Vis spectroscopic method. The result of this work is there is the highest amount of caffeine in Bohoro’s raw and roasted coffee bean in both aqueous and dichloromethane solvent extraction. The amount of caffeine in aqueous and dichloromethane extraction occurs in the range of 124.01 to 191.27 ppm and 145.15 to 200.09 ppm respectively in raw and roasted coffees. The aqueous phase coffee beans extract also hydrogen peroxide scavenging activity is nearly similar to ascorbic acid with similar concentration. There are a significant difference between Bohorow, Wurgisa, and Girana raw and roasted coffees in dichloromethane and aqueous extraction at α = 0.05.
Keywords
Caffeine, Coffee, Hydrogen peroxide scavenging, UV-Vis spectroscopy
