Structures and allelopathic effects ofNuphar alkaloids: Nupharolutine and 6,6'-dihydroxythiobinupharidine
1Department of Chemistry and Biochemistry, University of Southern Mississippi, 39406-5043, Hattiesburg, Mississippi.
Journal of Chemical Ecology
|November 15, 2013
Summary
The yellow water lily contains two main alkaloids: nupharolutine and 6,6'-dihydroxythiobinupharidine. Only 6,6'-dihydroxythiobinupharidine significantly inhibited plant growth in a lettuce bioassay.
Area of Science:
- Phytochemistry
- Plant Biology
- Biochemistry
Background:
- Nuphar lutea, commonly known as yellow water lily, is an aquatic plant.
- Alkaloids are a diverse group of naturally occurring organic compounds that contain at least one nitrogen atom.
Purpose of the Study:
- To isolate and identify major alkaloids from Nuphar lutea.
- To evaluate the biological activity of isolated Nuphar alkaloids on plant growth.
Main Methods:
- Isolation of alkaloids using chromatographic techniques.
- Lettuce seedling bioassay to assess phytotoxicity.
- Structure elucidation using Nuclear Magnetic Resonance (NMR) spectroscopy (DEPT, 1H-1H COSY, 1H-13C COSY, 1H-1H NOESY).
Main Results:
- Nupharolutine and 6,6 -dihydroxythiobinupharidine were successfully isolated from Nuphar lutea.
- Nupharolutine showed no significant inhibitory effect on radicle elongation.
- 6,6 -dihydroxythiobinupharidine exhibited significant phytotoxicity, inhibiting radicle elongation at concentrations above 2 ppm.
Conclusions:
- 6,6 -dihydroxythiobinupharidine is a potent phytotoxin present in Nuphar lutea.
- The study confirms the structures and stereochemistry of the isolated alkaloids.
- These findings contribute to understanding the allelopathic potential of Nuphar lutea.
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