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Free-radical-scavenging principles from Phlomis caucasica
Abbas Delazar1, Araz Sabzevari, Mahdi Mojarrab
1School of Pharmacy and Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Journal of Natural Medicines
|May 20, 2008
Summary
Seven compounds were isolated from Phlomis caucasica. Forsythoside B and acteoside demonstrated the most potent antioxidant activity, identified through DPPH assay.
Area of Science:
- Phytochemistry
- Pharmacology
- Natural Products Chemistry
Background:
- Phlomis caucasica is an Iranian medicinal plant with potential therapeutic properties.
- Phenolic compounds, including flavonoids and phenylethanoid glycosides, are known for their antioxidant activities.
Purpose of the Study:
- To isolate and identify free-radical-scavenging compounds from Phlomis caucasica.
- To evaluate the antioxidant potential of the isolated compounds using the DPPH assay.
Main Methods:
- Methanol extract of aerial parts of Phlomis caucasica.
- Isolation using reversed-phase preparative high-performance liquid chromatography (HPLC).
- Structure elucidation by spectroscopic methods.
- Antioxidant activity assessment using 2,2-diphenyl-1-picryl hydrazyl (DPPH) assay.
Main Results:
- Seven phenolic compounds were isolated: five flavonoids (rutin, chrysoeriol 7-O-rutinoside, kaempferol 3-O-glucoside, chrysoeriol 7-O-glucoside, naringenin) and two phenylethanoid glycosides (forsythoside B, acteoside).
- Forsythoside B (6) and acteoside (7) exhibited the most potent antioxidant activity.
- RC(50) values for forsythoside B and acteoside were 4.97 and 4.27 microg/ml, respectively.
Conclusions:
- Phlomis caucasica is a source of potent antioxidant compounds.
- Forsythoside B and acteoside are significant contributors to the antioxidant capacity of Phlomis caucasica.
- These findings support the traditional medicinal use of Phlomis caucasica and highlight its potential for developing new antioxidant agents.
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