Substances in olive products contribute to improved health as suggested by epidemiological data. In this study we assessed the effects of hydroxytyrosol (HT) on inflammatory mediators, cytokines and chemokines, and identified anti-inflammatory constituents of aqueous olive extracts, I.E., olive vegetation water (OVW). Murine macrophages (RAW264.7 cells) were stimulated with lipopolysaccharide (LPS) in the absence or presence of substances; inflammatory mediators [nitric oxide (NO), prostaglandin E₂ (PGE₂), cytokines, interleukins, chemokines] were determined by the Griess reaction, EIA, or multiplex ELISA (Luminex technology). Expression of inflammatory genes was determined by RT-PCR. Aqueous olive extracts were fractionated by preparative HPLC and the fractions investigated for their effects on NO and PGE₂ production. Results were further analyzed by principal component analysis. HT inhibited production of NO and PGE₂ with an IC₅₀ of 11.4 and 19.5 µM, respectively, reflecting strong anti-inflammatory activity. HT and OVW diminished secretion of cytokines (IL-1 α, IL-1 β, IL-6, IL-12, TNF- α), and chemokines (CXCL10/IP-10, CCL2/MCP-1). HT and OVW concentration-dependently reduced the expression of genes of inducible nitric oxide synthase (iNOS), IL-1 α, CXCL10/IP-10, MIP-1 β, matrix metalloproteinase-9, and prostaglandin E₂ synthase (PGES). The effects of HT were partly mediated VIA the NF- κB pathway, as shown by RT-PCR analysis. HT was identified as the main bioactive compound of OVW. The data provide a molecular basis for elucidating the effects of HT on inflammatory processes. The effects of HT on NO and chemokine production point to their impact on chronic inflammatory processes in endothelium or arthritis.

Die Kremplinge Paxillus atrotomentosus und P. panuoides produzieren in geringen Mengen orangegelbe Flavomentine und violette Spiromentine. Bei den Flavomentinen 1–3 handelt es sich um Ester des Atromentins (6) mit (2Z,4E)‐2,4‐Hexadiensäure oder (2Z,4S,5S)‐4,5‐Epoxy‐2‐hexensäure, außerdem kommt als weitere Verbindung dieses Typs 3‐O‐Acetylatromentin (4) vor. Die Spiromentine 8, 11, 12 und 13 besitzen eine ungewöhnliche Spirostruktur, in der ein 4,5‐Dihydroxy‐1,2‐benzochinon mit einem Lacton acetalartig verknüpft ist. Die spektroskopisch abgeleiteten Strukturen der Farbstoffe konnten durch die Synthese von Modellverbindungen und die biomimetische Überführung von Flavomentin B (2) in die Spiromentine B (11) und C (12) gesichert werden.

Atromentin (1) liegt in Fruchtkörpern des Samtfußkremplings hauptsächlich in Form der farblosen Leucomentine 3–5 vor. Die Leucomentine sind Ester des Leukoatromentins mit (2Z,4S,5S)‐4,5‐Epoxy‐2‐hexensäure, deren absolute Konfiguration durch Überführung in (+)‐O‐Acetylosmundalacton (6a) bestimmt werden konnte. Dabei wurde der Mechanismus der säurekatalysierten Abspaltung der Säurereste durch 18O‐Markierung aufgeklärt.

Vulpinic acid has been isolated from sporophores of Pulveroboletus ravenelii, its first reported occurrence in a Basidiomycete. Permethyl ethers of methyl xerocomate and methyl atromentate and its corresponding monochloro derivatives are produced by P. auriflammeus of Japanese origin.

Cultures and fruit bodies of Suillus bovinus produce the pulvinic acid derivative methyl bovinate (4), which contains an extra carbonyl group that bridges ring A of methyl variegatate with the hydroxy group at the central butenolide ring. This unprecedented structure was deduced fromthe spectroscopic data and confirmed by total synthesis via a grevillin intermediate. In this synthesis, the menthyl group was used for carboxyl protection.