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Three new α-pyrones, nocapyrones E-G (1-3), and three new diketopiperazine derivatives, nocazines A-C (4-6), together with a new oxazoline compound, nocazoline A (7), were isolated from the marine-derived actinomycete Nocardiopsis dassonvillei HR10-5. The new structures of 1-7 were determined by spectroscopic analysis, X-ray single-crystal diffraction, CD spectra, and modified Mosher and Marfey methods. Compounds 1-3 showed modest antimicrobial activity against Bacillus subtilis with MIC values of 26, 14, and 12 μM, respectively.

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Fucoxanthin and eicosapentaenoic acid (EPA) provide significant health benefits for human population. Diatom is a potential natural livestock for the combined production of EPA and fucoxanthin. In this study, first, the effects of three important parameters including light intensity, nitrogen concentration and salinity were evaluated for the production of EPA and fucoxanthin in two diatom strains Phaeodactylum tricornutum and Cylindrotheca fusiformis. And then, two steps method based on light intensity were applied to produce EPA and fucoxanthin in large scale. Higher light intensity was first adopted for the high growth rate and lipid content of diatom, and after a period of time, light intensity was lowered to enhance the accumulation of fucoxanthin and EPA. In final, the highest EPA yields were 62.55 and 27.32 mg L for P. tricornutum and C. fusiformis, and the fucoxanthin yield reached 8.32 and 6.05 mg L, respectively.

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Different culture conditions directed by the OSMAC (one strain-many compounds) approach drastically modified the metabolites of the fungus Spicaria elegans, which yielded the novel spicochalasin A (1), five new aspochalasins M-Q (2-6), and two known aspochalasins (7 and 8). The gross structures of 1-6 were elucidated by 1D and 2D NMR and MS methods, and their absolute configurations were determined by X-ray

Callus cells of Arabidopsis thaliana (cv. Landsberg erecta) were exposed for 8 h to a horizontal clinostat rotation (H, simulated weightlessness), a vertical clinostat rotation (V, clinostat control), or a stationary control (S) growth condition. The amount of glucose and fructose apparently decreased, while starch content increased in the H compared with the V- and S-treated cells. In order to investigate the influences of clinostat rotation on the cellular proteome further, the proteome alterations induced by horizontal and vertical clinostat rotation have been comparatively analysed by high-resolution two-dimensional (2-D) gel electrophoresis and mass spectrometry. Image analysis of silver-stained 2-D gels revealed that 80 protein spots showed quantitative and qualitative variations that were significantly (P <0.01) and reproducibly different between the clinorotated (H or V) and the stationary control samples. Protein spots excised from 2-D gels were analysed by microbe high performance liquid chromatography-ion trap-mass spectrometry (LC-IT-MS) to obtain the tandem mass (MS/MS) spectra. 18 protein spots, which showed significant expression alteration only under the H condition compared with those under V and S conditions, were identified. Of these proteins, seven were involved in stress responses, and four protein spots were identified as key enzymes in carbohydrate metabolism and lipid biosynthesis. Two reversibly glycosylated cell wall proteins were down-regulated in the H samples. Other proteins such as protein disulphide isomerase, transcription initiation factor IIF, and two ribosomal proteins also exhibited altered expression under the H condition. The data presented in this study illustrate that clinostat rotation of Arabidopsis callus cells has a significant impact on the expression of proteins involved in general stress responses, metabolic pathways, gene activation/transcription, protein synthesis, and cell wall biosynthesis.

Fractionation of the ethyl acetate extract of an acid-tolerant fungus, Penicillium purpurogenum JS03-21, resulted in the isolation of six new compounds, purpurquinones A-C (1-3), purpuresters A and B (4 and 5), and 2,6,7-trihydroxy-3-methylnaphthalene-1,4-dione (6), together with three known compounds, TAN-931 (7), (-)-mitorubrin (8), and orsellinic acid. The structures of 1-6 were elucidated primarily by NMR experiments. The absolute configurations of 1-4 were assigned on the basis of CD and NOESY data. Compounds 2-4 and 7 exhibited significant antiviral activity against H1N1, with IC50 values of 61.3, 64.0, 85.3, and 58.6 μM, respectively.