Sulfated flavanones and dihydroflavonols from willow

Area of Science:

• Phytochemistry
• Plant biochemistry
• Natural products chemistry

Background:

• Sulfated flavonoids are rare in plants, with limited prior characterization.
• Mammalian metabolism of dietary flavonoids involves sulfation, suggesting potential biological roles.

Purpose of the Study:

• To isolate and characterize novel sulfated flavonoids from Salix × alberti.
• To investigate the in vitro antioxidant properties of these compounds.

Main Methods:

• Phytochemical profiling using NMR spectroscopy and high-resolution mass spectrometry.
• Isolation of four sulfated flavonoids: taxifolin-7-sulfate, dihydrokaempferol-7-sulfate, eridictyol-7-sulfate, and naringenin-7-sulfate.
• DPPH radical scavenging assay to evaluate antioxidant activity.

Main Results:

• Four sulfated flavonoids, previously unobserved in plants, were identified and structurally elucidated.
• Sulfation of taxifolin and eriodictyol attenuated their antioxidant activity but did not eliminate it.

Conclusions:

• Salix × alberti is a source of unique sulfated flavonoids.
• 7-sulfation impacts the antioxidant capacity of flavonoids, offering insights into their biological functions and metabolism.