Xanthone Biosynthetic Pathway in Plants: A Review

Area of Science:

• Plant biochemistry
• Natural product biosynthesis
• Metabolomics

Background:

• Xanthones are diverse secondary metabolites with significant pharmacological properties.
• Plant xanthone biosynthesis pathways require comprehensive updates, particularly regarding recent discoveries up to 2021.
• Understanding these pathways is crucial for harnessing xanthones' therapeutic potential.

Purpose of the Study:

• To provide a detailed and updated review of plant xanthone biosynthesis pathways.
• To illuminate the intricacies and inter-species differences in xanthone formation.
• To serve as a resource for future research in xanthone-producing plants and synthetic biology.

Main Methods:

• Literature review focusing on plant xanthone biosynthesis.
• Analysis of the shikimate pathway and key intermediates like benzophenones.
• Examination of enzymes and reactions involved in xanthone ring formation and derivatization.

Main Results:

• Detailed elucidation of the xanthone biosynthetic pathway, starting from the shikimate pathway.
• Identification of key intermediates such as 2,3',4,6-tetrahydoxybenzophenone and core precursors 1,3,5-trihydroxyxanthone (1,3,5-THX) and 1,3,7-THX.
• Characterization of relevant enzymes and pathways for various downstream xanthone derivatives from species like *Hypericum* spp., *Centaurium erythraea*, and *Garcinia mangostana*.

Conclusions:

• This review presents one of the most complete overviews of plant xanthone biosynthesis to date.
• The findings provide a valuable foundation for directed molecular studies in xanthone-producing plants.
• The comprehensive pathway information supports future applications in synthetic biology for xanthone production.