[Show abstract][Hide abstract] ABSTRACT: Chemical investigation of the ethyl acetate extract of Trichoderma sp, a fungal endophyte isolated from Cola nitida (vent),
yielded two secondary metabolites identified as pretrichodermamide A (1) and nafuredin (2). The chemical structures were
elucidated by spectroscopic analysis including HRESIMS, 1H, 13C, DEPT, 1H-1H COSY, HMQC and HMBC. Cytotoxicity
was tested against mouse lymphoma cell line L5178Y, both compounds show no activity at the tested dose of 10 μg/ml. To
the best of our knowledge, this is the first report of the isolation of the endophyte Trichoderma sp, from the Nigerian
medicinal plant C. nitida
[Show abstract][Hide abstract] ABSTRACT: In this study the chemical composition and insecticidal evaluation of the essential oil of Mentha suaveolens L. and Mentha pulegium L. which are growing in Morocco were investigated. The volatile extract was isolated using hydro-distillation technique followed by continuous liquid-liquid fractionation (Water / Ethyl acetate). The essential oil was then analyzed by gas chromatography (GC) and gas chromatography - mass spectroscopy (GC-MS). The major compounds which are characterized in the essential oil of Mentha suaveolens L. were piperitenone (1) (33.03%), pulegone (2) (17.61%), piperitone (3) (9.18%); and of Mentha pulegium L. were pulegone (2) (73.33%), menthone (4) (8.63%). The study of the insecticidal activity of the essential oils on two species of devastating insects of the stored foodstuffs: Sitophilus oryzae and Rizopertha dominica was investigated. The mortality percentage of the species of insects was recorded in the first hours of treatment by the essential oils in the amount of 3, 12 and 50 µL.
[Show abstract][Hide abstract] ABSTRACT: Enniatins are mycotoxins which have important impact on human health, e.g. as contaminants of cereals, but also are discussed as possible anticancer agents. We investigated toxic effects of enniatins A1, B and B1 isolated from Fusarium tricinctum on different cancer cell lines. The enniatins showed moderate activity in HepG2 and C6 cells (EC50-values approximately 10–25 μM), but were highly toxic in H4IIE cells (EC50-values approximately 1–2.5 μM). In H4IIE cells, all enniatins increased caspase 3/7 activity and nuclear fragmentation as markers for apoptotic cell death. Enniatin A1, enniatin B1, and, to a lesser extent, also enniatin B decreased the activation of extracellular regulated protein kinase (ERK) (p44/p42), a mitogen-activated protein kinase which is associated with cell proliferation. Furthermore, enniatins A1 and B1, but not enniatin B were able to inhibit moderately tumor necrosis factor α (TNF-α)-induced NF-κB activation. Screening of 24 additional protein kinases involved in signal transduction pathways (cell proliferation, survival, angiogenesis and metastasis) showed no inhibitory activity of enniatins. We conclude that enniatins A1 and B1 and, to a lesser extent, enniatin B may possess anticarcinogenic properties by induction of apoptosis and disruption of ERK signalling pathway. Further analysis of these substances is necessary to analyse their usefulness for cancer therapy.
[Show abstract][Hide abstract] ABSTRACT: The endophytic fungus Stemphylium globuliferum was isolated from stem tissues of the Moroccan medicinal plant Mentha pulegium. Extracts of the fungus, which was grown on solid rice medium, exhibited considerable cytotoxicity when tested in vitro against L5178Y cells. Chemical investigation yielded five new secondary metabolites, alterporriol G (4) and its atropisomer alterporriol H (5), altersolanol K (11), altersolanol L (12), stemphypyrone (13), and the known compounds 6-O-methylalaternin (1), macrosporin (2), altersolanol A (3), alterporriol E (6), alterporriol D (7), alterporriol A (8), alterporriol B (9), and altersolanol J (10). The structures were determined on the basis of one- and two-dimensional NMR spectroscopy and mass spectrometry. Among the alterporriol-type anthranoid dimers, the mixture of alterporriols G and H (4/5) exhibited considerable cytotoxicity against L5178Y cells with an EC(50) value of 2.7 microg/mL, whereas the other congeners showed only modest activity. The compounds were also tested for kinase inhibitory activity in an assay involving 24 different kinases. Compounds 1, 2, 3, and the mixture of 4 and 5 were the most potent inhibitors, displaying EC(50) values between 0.64 and 1.4 microg/mL toward individual kinases.
[Show abstract][Hide abstract] ABSTRACT: This study reports the chemical investigation and cytotoxic activity of the secondary metabolites produced by the endophytic fungus Chaetomium sp. isolated from Salvia officinalis growing in Morocco. This plant was collected from the Beni-Mellal Mountain in Morocco and belongs to the Lamiaceae family and is named in Morocco “Salmia”. The endophytic fungus Chaetomium sp. was isolated from the tissues of the stem of this plant. The fungal strain was identified by PCR. The crude organic extract of the fungal strain was proven to be active when tested for cytotoxicity against L5178Y mouse lymphoma cells. Chemical investigation of the secondary metabolites showed that cochliodinol is the main component beside isocochliodinol. The structures of the isolated compounds were determined on the basis of NMR analysis (1H, 13C, COSY and HMBC) as well as by mass spectrometry using ESI (Electron Spray Ionisation) as source.