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A new chromene, (S)-banchromene (1), together with seven known compounds, ergosterol, beauvericin (2), fusaproliferin (3), radicinin (4), poly(3-hydroxybutyric acid) (PHB, 5), N-methylpyrrolidone and an inseparable mixture of isochromene derivatives 6a, 6b, were isolated from a culture of Fusarium sp. strain CAMKT24b1, an endophytic fungus from the leaves and twigs of Piper guineense (Piperaceae). The structures of these metabolites were elucidated on the basis of their spectroscopic data; the absolute configuration of 1 was determined by ab initio-calculation of the optical rotation. In tests with the zoospores of the grapevine downy mildew pathogen Plasmopara viticola, compounds 1-4 showed moderate to high levels of motility-impairing activity at concentrations as low as 2.5μg/mL. Compound 2 was the most active, exhibiting both motility-halting and lytic activities. Furthermore, compounds 2 and 3 displayed significant cytotoxic activity against brine shrimp larvae (Artemia salina) at 10μg/mL. This is the first report on motility inhibitory and lytic activities of metabolites from an endophytic Fusarium species against the zoospores of the downy mildew pathogen P. viticola. [ABSTRACT FROM AUTHOR]

The article presents a chemical structure related to an article on banchromene (I) and other secondary metabolites from the endophytic fungus Fusarium species by F.M. Talontsi and others, published in the "Tetrahedron Letters" in 2014.

A new dimeric naphtho-γ-pyrone, 2-hydroxydihydronigerone (1), along with five compounds, nigerone (2), pyrophen (3), kojic acid (4), 4-(hydroxymethyl)-5-hydroxy-2H-pyran-2-one (5), and p-hydroxyphenylacetic acid (6), was isolated from an endophytic fungus Aspergillus niger AKRN associated with the roots of Entandrophragma congoënse. The structure of the new compound has been elucidated using spectroscopic data including 1D and 2D NMR as well as the high-resolution mass spectrometry. Compounds 1–5 showed weak antimicrobial activity on five selected Gram-negative bacteria, namely Enterobacter aerogenes (CM64), Enterobacter cloacae (BM67), Klebsiella pneumonia (K2), and Escherichia coli (ATCC8739 and ATCC10536). [ABSTRACT FROM AUTHOR]

Betulinic acid (1), 5-hydroxy-3-methoxyxanthone (2), 1,6-dihydroxy-7-methoxyxanthone (3), daucosterol (4), bijaponicaxanthone C (5), hypercalin C (6), 1-hydroxy-6,7-dimethoxyxanthone (7), cadensin D (8) and 5-hydroxy-1,3-dimethoxyxanthone (9) were isolated from the roots of Hypericum riparium. These compounds are reported for the first time from this plant. The extracts and two of the isolated compounds (2 and 8) exhibited both antibacterial and antifungal activities that varied between the microbial species (MIC = 0.97- 250 µg/mL). In addition, the brine-shrimp (Artemia salina) lethality bioassay of compound 6 showed potent cytotoxicity with LD50 of 3.23 µg/mL. [ABSTRACT FROM AUTHOR]

We have independently investigated the source of tramadol, a synthetic analgesic largely used for treating moderate to severe pain in humans, recently found in the roots of the Cameroonian medicinal plant, Nauclea latifolia. We found tramadol and its three major mammalian metabolites (O-desmethyltramadol, N-desmethyltramadol, and 4-hydroxycyclohexyltramadol) in the roots of N. latifolia and five other plant species, and also in soil and local water bodies only in the Far North region of Cameroon. The off-label administration of tramadol to cattle in this region leads to cross-contamination of the soil and water through feces and urine containing parent tramadol as well as tramadol metabolites produced in the animals. These compounds can then be absorbed by the plant roots and also leached into the local water supplies. The presence of tramadol in roots is, thus, due to an anthropogenic contamination with the synthetic compound., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)