Triterpenoid saponins and other glycosides from the stems and bark of Jaffrea xerocarpa and their biological activity.

Six previously undescribed triterpenoid saponins and two previously undescribed norlupane triterpenes were isolated with five known saponins, three known lupane derivatives, 17,20-didehydro-20-deoxyjujubogenin, rutin, (±) 3α-O-β-d-glucopyranosyl-lyoniresinol, (±) 4-O-β-d-glucopyranosyl-maesopsin, three phenol glycosides, and uridine from the stems and bark of Jaffrea xerocarpa (Baill.) H. C.

Triterpenoids from the leaves of Alphitonia xerocarpus Baill and their biological activity.

Ten previously undescribed triterpenoid saponins and a previously undescribed norlupane triterpenoid were isolated, with three known saponins, four known flavonoids, two known lupane derivatives, sitosterol and 6'-heptadecanoyl-3-O-β-d-glucopyranosylsitosterol from the leaves of Alphitonia xerocarpus (Rhamnaceae), an endemic tree of New Caledonia. The chemical structures of the purified compounds were identified by nuclear magnetic resonance and mass spectrometry. The isolated compounds were tested for their antioxidant, antityrosinase, antibacterial and cytotoxic activity.

Fatal case of hemolytic-uremic syndrome in an adult due to a rare serogroup O91 Entero hemorrhagic Escherichia coli associated with a Clostridium difficile infection. More than meets the eye.

Hemolytic-uremic syndrome due to enterohemorrhagic Escherichia coli, belonging to serogroup O91 has rarely been described. We report here a case of post-diarrheal HUS due to EHEC O91 in an elderly patient for whom diagnosis was delayed given a previously diagnosed C. difficile infection.

Characterization of extended-spectrum beta-lactamase-producing Salmonella enterica serotype Brunei and Heidelberg at the Hussein Dey hospital in Algiers (Algeria).

The purpose of this work was to study the genetic determinants responsible for extended-spectrum cephalosporin (ESC) resistance of Salmonella collected during the period of 1995-2008 at the Hussein Dey hospital in Algiers (Algeria). Fourteen ESC-resistant Salmonella isolates were tested towards 22 antimicrobial agents. Polymerase chain reaction (PCR) and sequencing were used to determine the underlying genetic determinants responsible for the extended-spectrum beta-lactamase (ESBL) phenotypes.

Triterpenoid saponins from Symplocos lancifolia.

Three new bidesmosidic saponins (1-3) and a new ursane triterpenoid, 2α,3β,11α,23-tetrahydroxyurs-12-en-28-oic acid (4), along with seven known compounds, were isolated from a methanolic extract of the leaves of Symplocos lancifolia. The bidesmosidic saponins were found to possess the same sugar unit part, composed of two β-d-glucose moieties and one α-l-rhamnose moiety, linked to maslinic acid, arjunolic acid, and asiatic acid, respectively. Their structures were elucidated by interpretation of their 1D and 2D NMR spectra and completed by analysis of the HRESIMS data.

Isoflavonoid glycosides from the roots of Baphia bancoensis.

Chemical investigation of the methanol extract of the roots of Baphia bancoensis led to the isolation and characterization of three new isoflavonoid glycosides (1-3). Their structures were determined on the basis of spectroscopic studies andchemical evidence. Antibacterial activity of isolated compounds was evaluated against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa.