Page Banner

United States Department of Agriculture

Agricultural Research Service

Title: Phenolic Content and Antioxidant Activity of Extracts from Whole Buckwheat (Fagopyrum esculentum Moench) With or Without Microwave Irradiation

Authors
item INGLETT, GEORGE
item Rose, Devin
item CHEN, DIEJUN
item BISWAS, ATANU

Submitted to: Journal of Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 22, 2009
Publication Date: July 26, 2009
Citation: Inglett, G.E., Rose, D.J., Chen, D., Biswas, A. 2009. Phenolic Content and Antioxidant Activity of Extracts from Whole Buckwheat (Fagopyrum esculentum Moench) With or Without Microwave Irradiation. Journal of Food Chemistry. 119:1216-1219.

Interpretive Summary: This research on buckwheat extract with enhanced phenolic content and antioxidant activity will benefit the food manufacturers and nutraceutical companies in their ability to improve nutrition of human diets. Many of the health benefits of buckwheat have been attributed to its high levels of phenolic compounds, which exhibit antioxidant activity. In contrast to most cereal grains, buckwheat contains a majority of phenolic compouns present in the free form, allowing their extraction with proper solvents. The purpose of this study was to evaluate the effectiveness of extracting phenolic compounds with antioxidant activity from buckwheat using microwave irradiation or a water bath at various temperatures. The phenolic content of extracts increased with increasing temperature and in general, phenolic contents in microwave irradiated extracts were higher than those heated with a water bath. This study showed that microwave irradiation can be used to obtain buckwheat extracts with higher phenolic content and similar antioxidant activity as extracts heated in a water bath.

Technical Abstract: The purpose of this study was to evaluate the effectiveness of extracting phenolic compounds and antioxidant activity from buckwheat with water, 50% aqueous ethanol, or 100% ethanol using microwave irradiation or a water bath for 15 min at various temperatures (23 – 150 °C). The phenolic content of extracts increased with increasing temperature. In general, phenolic contents in microwave irradiated extracts were higher than those heated with a water bath. The highest phenolic content was observed in the buckwheat extract that had been microwave irradiated in 50% aqueous ethanol at 150 °C. The highest antioxidant activities were found in the 100% ethanol extracts corresponding to the highest extraction temperatures (100 and 150 °C), independent of heat source. This study showed that microwave irradiation can be used to obtain buckwheat extracts with higher phenolic content and similar antioxidant activity as extracts heated in a water bath.

Last Modified: 9/10/2014