Antioxidant activity and total phenolic content of aqueous and methanolic extracts of Jordanian plants: an ICBG project

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Nicholas Oberlies, Associate Professor (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/

Abstract: As part of an International Cooperative Biodiversity Groups (ICBG) program to study Jordan's biodiversity, the relative levels of antioxidant activity and the total phenolic content of aqueous and methanolic extracts of a total of 95 plant species, all of Jordanian origin and those collected at random, have been measured. The total phenolic content of aqueous and methanolic extracts of the investigated plant species ranged from 4.4 to 78.3 mg and from 2.1 to 52.8 mg gallic acid equivalents g-1 dry weight, respectively, while the total antioxidant capacity ranged from 20.0 to 916.7 and from 15.1 to 915.6 µmol Trolox equivalents g-1 dry weight, respectively. Based on this collection, approximately 5% of assayed plants showed high levels of antioxidant activity. There was a significant linear correlation between antioxidant activity and total phenolic content for aqueous and methanolic extracts, suggesting that phenolic compounds were the predominant antioxidant components in the investigated plant species. Interestingly, a few of the collected plants had high-antioxidant activity yet “low” phenolic content includes Ceratonia siliqua and Viscum cruciatum. These plants may serve as sources of antioxidants with new chemotypes.

Additional Information

Publication
Natural Product Research. 21, 1121-1131
Language: English
Date: 2007
Keywords
Antioxidants, Total phenolic content, Jordanian flora, Free radicals