Studies On The Chemical Constituents Of Ganoderm Acochlear

Objective: Many Ganoderma species are famous traditional medicines.However,for a long time have triterpenoids and polysaccharides been considered as the major constituents in the genus.In the recent years,our group has identified several renal protective or neuroprotective meroterpenoids from the fungi of this genus,revealing a new class of bioactive compounds of Ganoderma species.With the purpose to explore the structur diversity of meroterpenoids and pave the way for further application of Ganoderma fungi,we undertook the investigation of the title specie which is widely seen in the markets and utilized in Chinese folk.Methods: The powders of G.cochlear fruiting bodies were refluxed with aqueous EtOH?80%?and concentrated under reduced pressure to yield a crude extract.An aliquote?1000 g?was suspended in water and partitioned with CHCl₃ three times followed by removing solvents to afford 420 g extracts.300 g of which was separated via column chromatography or preparative thin layer chromatography on using silica gel,MCI Gel CHP 20 P,RP-18 or Sephadex LH-20 to yield 37 compounds.Their structures were identified by spectroscopic methods including 1D and 2D NMR,MS and UV.Of note the absolute configuration determination of the isolated enantiomers are running by computational methods.In addition,in vitro biological evaluation of some isolates was conducted using COX-2.Results: In the present study,37 compounds including 35 new compounds and 2k nowcompoundswere isolated from G.cochlear.Their planarstructures apart from abs olute configurations were assigned.Both the literatures and our work indicate that most meroterpenoids were isolated as racemic mixtures.Thus we carried out chiral separation against some of the isolated meroterpenoids to yield their individual en antiomers.Bioassay revealed that the most tested compounds exhibit potent anti-infl ammatory activity against COX-2 with IC₅₀ valuse less than 10 ?M.Conclusion:In total,35 structurally novel meroterpenoids were characterized from the title specie.Some structures share common motifs with the reported such type of compounds.Whereas,the most isolates are unique in structures implying the intriguing mechanisms of this fungus making meroterpenoids.Last but not the least,the the findings of anti-inflammatory property of meroterpenoids not only disclose diverse bioactivities but also lend a hand for further G.cochlear based product development.