RÉSUMÉ
Five batches of resin from the Pili tree (Canarium ovatum Engl.) were distilled, and their essential oils and hydrosols were analyzed by gas chromatography. The oils, obtained in yields of 13.4-19.7 % v/m, featured α-phellandrene in high proportions (50-65 %), alongside limonene, ß-phellandrene and para-cymene. Chiral GC analysis confirmed that both phellandrenes were in fact >95 % (S)-(+) enantiomers, while the other monoterpenes featured less pronounced enantiomeric excesses. The hydrosols were rich in α-phellandrene oxidation products including cis-α-phellandrene epoxide and a series of para-menth-5-ene-1,2-diol isomers. Both essential oils and hydrosols were tested for their antibacterial activity against Escherichia coli and Staphylococcus aureus and exhibited MIC90 of less than 5 and 0.5â mg/mL of total volatiles, respectively. The essential oil features some potential as a source of readily available natural (S)-(+)-α-phellandrene.
Sujet(s)
Antibactériens/pharmacologie , Burseraceae/composition chimique , Huile essentielle/pharmacologie , Résines végétales/composition chimique , Antibactériens/composition chimique , Chromatographie en phase gazeuse/méthodes , Escherichia coli/effets des médicaments et des substances chimiques , Tests de sensibilité microbienne , Huile essentielle/composition chimique , Staphylococcus aureus/effets des médicaments et des substances chimiquesRÉSUMÉ
Phytochemical analysis of A. balsamea oleoresin led to the isolation of three new 3,4-seco-lanostane triterpenoids 1-3, one new cycloartane triterpenoid 4 along with fourteen known terpenoids. Structure determinations were based on extensive 1D/2D NMR, IR and MS spectroscopic analyses, and comparison with literature data. The isolated compounds were evaluated in vitro for their cytotoxicity against human cell lines (A549, DLD-1, WS1) and their antibacterial activity against E. coli and S. aureus. Abiesonic acid (6) exhibited weak cytotoxic activity against A549 (IC50 = 22 µM) while compounds 1 and 4 were weakly active against S. aureus (MIC = 25 µM).
RÉSUMÉ
Abibalsamins A (1) and B (2), two unprecedented tetraterpenoids featuring a 3,4-seco-rearranged lanostane system fused with a ß-myrcene lateral chain via a [4 + 2] Diels-Alder cycloaddition, were isolated from the oleoresin of Abies balsamea. Their structures were elucidated by means of extensive 2D NMR, IR, and MS spectroscopy analyses. The absolute configuration of 1 was determined by single-crystal X-ray diffraction. Both compounds exhibited significant cytotoxic activity against cancer cell lines.
