stilbenes

Stilbenes are a class of natural phenolic compounds characterized by a 1,2‑diphenylethylene backbone (C6‑C2‑C6). The core structure consists of two aromatic rings linked by a two‑carbon ethylene bridge, which may be substituted with hydroxyl, methoxy, or other functional groups. This simple scaffold gives rise to a diverse family of metabolites found in many plant species, fungi, and some bacteria.

In plants, stilbenes function primarily as phytoalexins, low‑molecular‑weight compounds produced in response to biotic stress such as pathogen attack or herbivory. The most widely studied stilbene is resveratrol, isolated from the roots of Vitis vinifera and present in grape skins, peanuts, and berries. Other notable members include pterostilbene, piceatannol, and astringin. Biosynthesis proceeds via the phenylpropanoid pathway, where the enzyme stilbene synthase condenses p‑coumaroyl‑CoA with three molecules of malonyl‑CoA to form the stilbene scaffold.

Stilbenes exhibit a range of biological activities that have attracted scientific interest. Antioxidant, anti‑inflammatory, and cardioprotective effects have been reported for several compounds, especially resveratrol, which has been investigated for its potential role in longevity and disease prevention. Additionally, certain stilbenes possess antifungal and antibacterial properties, contributing to the plant’s defensive arsenal.

Commercially, stilbenes are used in dietary supplements, functional foods, and cosmetics, often marketed for their purported health benefits. Their stability can be limited by oxidation and photo‑isomerisation, prompting formulation strategies such as encapsulation or derivatization. Ongoing research explores synthetic analogues and metabolic engineering approaches to enhance production and tailor biological activity, underscoring stilbenes’ continued relevance in pharmacology, agriculture, and biotechnology.