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A novel antioxidant phenanthrenoid dimer from Juncus acutus L.
Fathi A A Behery1, Zain-Elabdin M Naeem, Galal T Maatooq
1Department of Pharmacognosy, Faculty of Pharmacy, Mansoura 35516, Egypt.
Natural Product Research
|February 25, 2012
Summary
A novel dimer from Juncus acutus L. exhibits potent antioxidant activity. However, dimerisation of dehydrojuncusol significantly reduced its anti-inflammatory properties against inducible nitric oxide synthase (iNOS) protein expression.
Area of Science:
- Natural Product Chemistry
- Pharmacology
- Plant Biochemistry
Background:
- The halophyte Juncus acutus L. is a source of diverse phytochemicals.
- Phenanthrenoids and flavonoids are classes of natural products with known biological activities.
Purpose of the Study:
- To isolate and characterize novel compounds from Juncus acutus L.
- To evaluate the antioxidant and anti-inflammatory potential of isolated compounds.
Main Methods:
- Isolation and purification of compounds using chromatographic techniques.
- Structural elucidation via spectroscopic analyses, including 2D NMR.
- In vitro antioxidant activity assessed using the ABTS radical cation decolourisation assay.
- In vitro anti-inflammatory activity evaluated in lipopolysaccharide-stimulated RAW264.7 macrophage cells.
Main Results:
- A novel symmetrical phenanthrenoid dimer, 8,8'-bidehydrojuncusol, was isolated along with related compounds.
- The new dimer and other phenolic compounds demonstrated significant in vitro antioxidant activity, comparable to ascorbic acid.
- Dimerisation of dehydrojuncusol nearly abolished its inhibitory effect on inducible nitric oxide synthase (iNOS) protein expression in macrophages.
Conclusions:
- Juncus acutus L. yields structurally unique phenanthrenoids with notable antioxidant capacity.
- The biological activity of phenanthrenoids can be significantly altered by dimerization, impacting their anti-inflammatory potential.
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