Valepotriates

Valepotriates are a class of ester compounds found in valerian (Valeriana officinalis) root and rhizome. They are believed to arise from valepotriol, a volatile monoterpene framework, through esterification with valeric acid derivatives, producing several closely related compounds reported in the literature, sometimes grouped as valepotriates B, C, and others. Valepotriates are notable for their instability: they hydrolyze and rearrange under heat, light, or prolonged storage, so their levels decline over time in dried material and commercial extracts. The instability also means that valepotriate content can vary among preparations and tends to be higher in fresh material.

Valepotriates are predominantly associated with valerian root, though related compounds may occur in other Valeriana species. They contribute to the characteristic odor of valerian preparations and are often used as a quality-control marker in phytopharmaceuticals to indicate the presence of certain valerian constituents.

Pharmacological evidence for valepotriates’ specific activity is limited. Some studies have linked valerian extracts with sedative effects and have suggested a role for valepotriates, but much of the observed activity is believed to result from the combined action of multiple constituents, including valerenic acids and valerenal. The chemical instability of valepotriates complicates pharmacological testing, standardization, and storage of valerian products.

Analytical methods, particularly high-performance liquid chromatography (HPLC), are used to quantify valepotriate content in extracts. Storage recommendations emphasize protecting valerian products from heat and light to preserve valepotriates.