Nematicidal sphingolipids from the freshwater fungusParaniesslia sp. YMF1.01400

Two new sphingolipids from the leaves of Piper betle L

Two new sphingolipids, pipercerebrosides A (1) and B (2), were isolated from the leaves of Piper betle L. Their structures, including absolute configurations, were determined by spectroscopic analysis and chemical degradation. These two compounds did not show significant cytotoxic activity against the cancer cell lines K562 and HL-60 in a MTT assay.

Ophiocerol, a novel macrocylic neolignan from the aquatic fungus Ophioceras dolichostomum YMF1.00988

From cultural filtrates of the freshwater fungus Ophioceras dolichostomum YMF1.00988 a novel neolignan with an unprecedented dibenzo-1,6-dioxacyclodecane carbon skeleton, ophiocerol (1), was isolated, and the known compounds isoamericanoic acid A (2) and caffeic acid (3) were identified. The structure of the novel compound was determined by interpretation of its spectroscopic data, including 1D and 2D, (1)H and (13)C NMR (COSY, HMQC, HMBC, NOESY), and MS. Compounds 1-3 were assayed for their nematicidal activity against Bursaphelenchus xylophilus as well as their antifungal activity against several plant pathogen fungi.

Two unusual naphthalene-containing compounds from a freshwater fungus YMF 1.01029

Two novel naphthalene-containing compounds, colelomycerones A and B (1 and 2, resp.), and three known metabolites, including preussomerin D (3), (2RS,2'SR,3'E,3SR,4E,8E)-1-O-(beta-D-glucopyranosyl)-3-hydroxy-2-[(2-hydroxyoctadec-3-enoyl)amino]-9-methyloctadeca-4,8-diene (4), and 3beta-hydroxy-5alpha,8alpha-epidioxyergosta-6,22-diene (5), were isolated from the culture broth of an unidentified freshwater water fungus YMF 1.01029. This fungus was collected from a decaying branch of an unidentified tree near Lake Fuxian in Yunnan Province, China. The structures of these five compounds were determined on the basis of their spectroscopic and mass-spectrometric data. Colelomycerones A and B (1 and 2, resp.) represent unprecendented examples of naphthalene-1,2-diones with novel cyclic acetals. Compounds 1-3 showed noticeable antifungal and antibacterial activities.

Sphingolipids with neuritogenic activity from Euphorbia sororia

Two groups of sphingolipids 1 and 2 were isolated from the aerial parts of Euphorbia sororia. On the basis of spectroscopic data, chemical methods and GC-MS analysis, the structures of 1 and 2 were characterized as 1-O-beta-D-glucopyranosyl-(2S,3S,4R,8Z)-2-[(2'R)-2'-hydroxydocosanoyl approximately hexacosanoyl, octacosanoyl amino]-1,3,4-octadecanetriol-8-ene and (2S,3S,4R,8E)-2-[(2'R)-2'-hydroxyeicosanoyl approximately hexacosanoyl amino]-1,3,4-octadecanetriol-8-ene, respectively. Both of them exhibited marked neuritogenic activity on the rat pheochromocytoma PC12 cell line.

Nematicidal Resorcylides from the Aquatic Fungus Caryospora callicarpa YMF1.01026

This study investigated metabolites with activities against plant parasite nematodes from the fresh-water fungus Caryospora callicarpa YMF1.01026. We obtained three novel tetradecalactone metabolites, caryospomycins A-C, with such activities. The chemical structures of these were determined through NMR spectroscopic analysis and were found to belong to the 14-membered macrolides with a fused 1,2-dimethoxy-4-hydroxybenzene ring, a rare structure among the resorcylides. In the in vitro tests, all three compounds exhibited moderate killing activity against the nematode Bursaphelenchus xylophilus. To our knowledge, this is the first report of secondary metabolites in the aquatic fungal genus Caryospora.