Determination of Caffeine and Hydrogen Peroxide Antioxidant Activity of Raw and Roasted Coffee Beans Around Habru Woreda, Ethiopia Using UV-Vis Spectroscopy

Abstract

Background: Coffee is a well-known beverage that is widely used around the world. Despite the wide use of coffee in Ethiopia, there is a lack of extensive studies addressing the issues related to the caffeine content and hydrogen peroxide antioxidant activity of varieties of coffee types, particularly in Habru woreda, Ethiopia. Objective: This study aimed to determine the caffeine content and hydrogen peroxide antioxidant activity of raw and roasted coffee beans collected directly from Habru woreda, North Wollo zone of Ethiopia. Methods: The study was conducted in Bohoro, Girana, and Wurgisa kebeles of Habru woreda, Ethiopia, by collecting 500 g of green beans of Arabica coffee without considering their variety. Then, the collected beans were divided into raw and roasted coffee to perform aqueous and dichloromethane extraction of their caffeine content and hydrogen peroxide antioxidant activity using UV-Vis spectrophotometry. Results: The amounts of caffeine in aqueous and dichloromethane extraction were in the range of 124.01−191.27 ppm and 145.15−200.09 ppm in raw and roasted coffees, respectively. Using the IC 50 value, the hydrogen peroxide scavenging activity of the aqueous phase coffee bean extracts in Bohoro raw, Bohoro roasted, Wurgisa raw, Wurgisa roasted, Girana raw, and Girana roasted coffee were 32.17 ppm, 11.69 ppm, 26.14 ppm, 3.12 ppm, 24.83 ppm, and 11.06 ppm, respectively, while that of ascorbic acid was 6.91 ppm. Conclusion:The study showed that the highest amount of caffeine in both aqueous and dichloromethane solvent extraction was found in Bohoro's raw and roasted coffee beans. Also, the amounts of caffeine in all coffee bean samples were safe and the antioxidant activity was excellent. In most of the samples, significant variations in the concentration of caffeine in raw and roasted coffee bean samples were observed in the two extraction solvents.

Coffee Fruit Roasting: An Approach To Enhance Yield and Bioactivities of Ethanol Extracts from Coffee Husk

“…Coffee husk roasted at 150 °C for 25 min exhibited a hydrogen peroxide scavenging capacity comparable to ascorbic acid. Roasted and unroasted coffee cherry beans processed by the dry method from various regions yielded comparable results, with percentages ranging from 39.90 ± 1.35 to 83.38 ± 0.85% . Because there are no other reports of the hydrogen peroxide capacity of coffee cherry husk or other coffee byproducts, we compared our results to berry fruit byproducts with similar compositions to coffee husk; results were comparable (57.9–73.9%) .…”

“…Roasted and unroasted coffee cherry beans processed by the dry method from various regions yielded comparable results, with percentages ranging from 39.90 ± 1.35 to 83.38 ± 0.85%. 79 Because there are no other reports of the hydrogen peroxide capacity of coffee cherry husk or other coffee byproducts, we compared our results to berry fruit byproducts with similar compositions to coffee husk; results were comparable (57.9−73.9%). 80 The variation may be due to different extraction methods and variations in the raw material used.…”

Antibacterial, Antioxidant Potency, and Chemical Composition of Essential Oils from Dried Powdered Leaves and Flowers of Hypericum revolutum subsp. keniense (Schweinf.)

“…The absorbance of the solutions was measured at 230 nm against a blank consisting of phosphate buffer (pH 7.4) only. All the tests were performed in triplicates, and the scavenging activity of hydrogen peroxide was calculated using the formula stipulated by Legas Muhammed et al [ 31 ]. where A 0 is the absorbance of the control reaction and A 1 is the absorbance in the presence of the samples or standards.…”

High‐pressure processing‐assisted in‐situ extraction of caffeine, chlorogenic acid, phenolic content, and antioxidant properties of green coffee bean

“…Caffeine from the GCE was extracted using dichloromethane in a solvent ratio of 1:4 (v/v), following a modified version of the method reported by Muhammed et al (2021). In this procedure, the GCE from each treatment combination was mixed with dichloromethane in a volume ratio of 2:2 mL to facilitate caffeine extraction.…”