A novel substance with allelopathic activity in Ginkgo biloba

Area of Science:

• Phytochemistry
• Plant Physiology
• Natural Products Chemistry

Background:

• Ginkgo biloba is an ancient tree species with extensive traditional medicinal use.
• Ginkgo leaf extracts, like EGb761, are commercially significant herbal products.
• No plant-directed bioactive compounds had been previously identified in Ginkgo species.

Purpose of the Study:

• To investigate the allelopathic activity of Ginkgo biloba leaves.
• To identify and characterize novel allelopathic substances from Ginkgo leaves.
• To assess the potential of identified compounds as plant control agents.

Main Methods:

• Preparation of aqueous methanol leaf extract from Ginkgo biloba.
• Testing extract's effect on seedling growth of garden cress, lettuce, timothy, and ryegrass.
• Purification of the active compound using chromatographic techniques.
• Identification of the isolated compound via spectral analysis.

Main Results:

• Ginkgo leaf extract significantly inhibited root and shoot growth in tested seedlings.
• A novel compound, 2-hydroxy-6-(10-hydroxypentadec-11-enyl)benzoic acid, was isolated and identified.
• The novel compound demonstrated significant inhibition of garden cress and timothy growth at concentrations above 3 μM.
• Its activity was substantially higher than that of nonanoic acid.

Conclusions:

• The identified compound, 2-hydroxy-6-(10-hydroxypentadec-11-enyl)benzoic acid, likely contributes to the allelopathic effects of Ginkgo leaf extract.
• This novel compound may serve as a lead structure for developing new herbicides or plant growth regulators.