Comparison of the chemical composition of three species of smartweed (genus Persicaria) with a focus on drimane sesquiterpenoids

• Published in: Phytochemistry (Oxford) Vol. 108; pp. 129 - 136
• Main Authors: Prota, N., Mumm, R., Bouwmeester, H.J., Jongsma, M.A.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.12.2014
• Subjects: antifeedant; Drimane; Ecosystem; flavonoids; Flowers - chemistry; Fruit - chemistry; Gas Chromatography-Mass Spectrometry; GC–MS; humans; Molecular Structure; Persicaria hydropiper; Persicaria maculosa; Persicaria minor; Plant Leaves - chemistry; Polygodial; Polygonaceae; Polygonaceae - chemistry; Polygonaceae - genetics; Polygonum; polygonum genus; Seeds - chemistry; Sesquiterpenes - chemistry; Sesquiterpenes - isolation & purification; Terpenes; Water-pepper; Polygonum; GC–MS; Persicaria maculosa; Polygonaceae; Persicaria hydropiper; Water-pepper; Polygodial; Persicaria minor; Drimane; Terpenes
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/j.phytochem.2014.10.001

Three species of smartweed (genus Persicaria), found in the same habitat, but with strongly different contents of polygodial. [Display omitted] •Twenty-nine secondary metabolites of three Persicaria species were compared.•The drimane contents specifically differed 200–100,000 fold between the three species.•Second stage flowers of P. hydropiper had the highest drimane content.•The headspace of P. hydropiper contained 8 compounds, but none were drimanes. The genus Persicaria is known to include species accumulating drimane sesquiterpenoids, but a comparative analysis highlighting the compositional differences has not been done. In this study, the secondary metabolites of both flowers and leaves of Persicariahydropiper, Persicariamaculosa and Persicariaminor, three species which occur in the same habitat, were compared. Using gas chromatography–mass spectrometry (GC–MS) analysis of extracts, overall 21/29 identified compounds in extracts were sesquiterpenoids and 5/29 were drimanes. Polygodial was detected in all species, though not in every sample of P. maculosa. On average, P. hydropiper flowers contained about 6.2mggFW−1 of polygodial, but P. minor flowers had 200-fold, and P. maculosa 100,000 fold lower concentrations. Comparatively, also other sesquiterpenes were much lower in those species, suggesting the fitness benefit to depend on either investing a lot or not at all in terpenoid-based secondary defences. For P. hydropiper, effects of flower and leaf development and headspace volatiles were analysed as well. The flower stage immediately after fertilisation was the one with the highest content of drimane sesquiterpenoids and leaves contained about 10-fold less of these compounds compared to flowers. The headspace of P. hydropiper contained 8 compounds: one monoterpene, one alkyl aldehyde and six sesquiterpenes, but none were drimanes. The potential ecological significance of the presence or absence of drimane sesquiterpenoids and other metabolites for these plant species are discussed.