Abstract
AbstractPlant samples from several species and populations of the genus Sideritis (Labiatae) grown in Bulgaria (S scardica, S syriaca and S montana) were extracted with different solvents. Their antioxidant activities were determined by the β‐carotene bleaching test (BCBT), 2,2′‐diphenyl‐1‐picrylhydrazyl (DPPH•) radical scavenging method and static headspace gas chromatography (HS‐GC) and compared with the antioxidant activity of two reference compounds of different polarity, viz butylated hydroxytoluene (BHT) and rosmarinic acid. The pure reference compounds were applied in a ten‐times lower concentration than the plant extracts. The highest antioxidant activity in the BCBT, close to that of BHT, was observed for the more apolar extracts. The inhibitory effect on β‐carotene bleaching of the polar extracts and rosmarinic acid was much lower than that of BHT. The inhibition of hexanal formation in bulk safflower oil by most of S syriaca and S scardica extracts was as effective as BHT but less so than rosmarinic acid. S montana extracts showed weak antioxidant or even pro‐oxidant properties. Extracts from butanol and from ethyl acetate and the total methanol extracts from all Sideritis plants studied showed a strong radical scavenging activity against DPPH•, close to that of rosmarinic acid. S montana extracts were, as a whole, slightly weaker radical inhibitors than the extracts from the other two species. The antioxidant activity of Sideritis extracts was attributed to the presence of flavonoid and phenylpropanoid glycosides. Copyright © 2003 Society of Chemical Industry
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
