New bisabolane sesquiterpenoids from a marine-derived fungus Aspergillus sp. isolated from the sponge Xestospongia testudinaria

Three new phenolic bisabolane sesquiterpenoid dimers, disydonols A-C (1-3), and one known compound (S)-(+)-sydonol (4) were isolated from the fermentation broth of a marine-derived fungus Aspergillus sp., which was isolated from the sponge Xestospongia testudinaria collected from the South China Sea. Their structures were elucidated on the basis of comprehensive spectral analysis including 1D and 2D NMR spectra and HR-ESI-MS. These compounds were evaluated for cytotoxic activity against HepG-2 and Caski human tumour cell lines. Among them, compounds 1 and 3 exhibited cytotoxicity against the two cell lines.     

Cytotoxic scalarane sesterterpenes from a Korean marine sponge Psammocinia sp.

Three novel scalarane sesterterpenes were isolated from a Korean marine sponge, Psammocinia sp., along with four known derivatives. Their structures were elucidated on the basis of NMR, MS and IR spectroscopic data. The three new compounds are 12-deacetoxy-23-hydroxyscalaradial (1), 12-dehydroxy-23-hydroxyhyrtiolide (2) and 12-O-acetyl-16-deacetoxy-23-acetoxyscalarafuran (3), respectively, and the four known compounds are 12-deacetoxy-23-hydroxyheteronemin (4), 12-deacetoxy-23-acetoxy-19-O-acetylscalarin (5), 12-deacetoxy-23-O-acetoxyheteronemin (6) and 12-deacetoxyscalaradial (7). They exhibited cytotoxicity against intractable human cancer cell lines A498, ACHN, MIA-paca and PANC-1, with an IC₅₀ range of 0.4–48 μM.     

Thermoluminescence in pumice stone collected from the Mediterranean coast

Pumice is a low-density, light-coloured volcanic rock (igneous rock) formed when the magma from a volcanic eruption is suddenly cooled. It has a porous structure and can be different colours and have different densities. Pumice stone, unlike other rock, does not sink in water because it has a low density. In the present study, the thermoluminescent (TL) dosimetric characteristics, such as the dose–response, TL signal fading as a function of storage time, heating rate, and reusability of pumice collected on the Mediterranean coast were investigated. From this study, it was concluded that the pumice stone showed TL properties with a TL glow curve including an obviously wide peak at ∼200°C. A wide linear dose–response region up to 144 Gy, low fading of the TL signal when it was kept in a dark room for a long time, and poor reusability properties were observed for dosimetry use.     

Novel spiciferone derivatives from the fungus Drechslera hawaiiensis isolated from the marine sponge Callyspongia aerizusa

From the marine sponge Callyspongia aerizusa collected from the Sea of Bali, Indonesia, fungal isolates of Drechslera hawaiiensis were obtained. Culture filtrates of the fungus yielded four spiciferone derivatives which include spiciferone A (1) and B (2), and two other novel derivatives including spiciferol A (3) which is an alcohol congener of spiciferone A (1) and compound 4 which is an monocyclic spiciferone congener featuring a butoxyl side chain. The structures of the novel compounds were established on the basis of NMR spectroscopic (1H, 13C, COSY) and mass spectrometric (EIMS) data.     

New p-terphenyls from the endophytic fungus Aspergillus sp. YXf3

Five new p-terphenyls named prenylterphenyllin D (1), prenylterphenyllin E (2), 2′-O-methylprenylterphenyllin (3), 4-O-methylprenylterphenyllin (4) and 3′-O-methylterphenyllin (5) together with seven known compounds (6–12), were isolated from cultures of Aspergillus sp. YXf3. The structures of the new compounds were elucidated by extensive MS and NMR analyses. The NMR and MS data of 5 is reported for the first time, as its structure was listed in SciFinder Scholar with no associated reference. Compounds 6 and 7 were distinguished from each other on the basis of 2D NMR experiments. Compounds 1, 2, 3 and 8 showed antibacterial activities against X. oryzae pv. oryzicola Swings and E. amylovora with the same MIC values of 20 μg/mL while 10 exhibited activities against E. amylovora with an MIC value of 10 μg/mL.     

Studies on the secondary metabolites of a Pseudoalteromonas sp. isolated from sediments collected at the northeastern coast of Brazil

Continuing search for anticancer compounds from the marine environment, we have studied microorganisms that inhabit intertidal sediments of the northeastern Brazilian coast. Of the 32 strains isolated, 13 were selected for biological evaluation of their crude extracts. The acetate extract obtained from a Gram-negative bacterium was strongly active against cancer cell lines with IC(50) values that ranged from 0.04 (HL60 leukemia cells) to 0.26 μg/ml (MDA MB-435 melanoma cells). The bacterium was identified as a Pseudoalteromonas sp. based on 16S rRNA gene sequencing. A bioassay-guided fractionation of the active extract led to the isolation of prodigiosin, a well-known tripyrrole red pigment with immunosuppressive and anticancer activities. Further experiments with ErbB-2 overexpressing cell lines, including HB4a-C3.6 (moderate overexpression), HB4a-C5.2 (high overexpression), and the parental HB4a cell line, were performed. Prodigiosin was moderately active toward HB4a cells with an IC(50) of 4.6 μg/ml, while it was 115 and 18 times more active toward HB4a-C3.6 cells (IC(50) of 0.04 μg/ml) and HB4a-C5.2 (IC(50) of 0.26 μg/ml) cells, respectively. These data suggest that, in spite of its previously described apoptosis-inducing properties, prodigiosin can selectively recognize cells overexpressing ErbB-2, which could be highly appealing in human breast cancer therapy.     

Novel triterpene glycosides from the sponge Ulosa sp

New triterpene glycosides, ulososides C, (20S,22S,23R,24S)-3 beta,22, 23-trihydroxy-3-O-(beta-D-glucopyranosyl)-32-nor-24-methyllanost- 8(9)-ene-30-oic acid, D, (20S,22S,23R,24S)-3 beta,22, 23-trihydroxy-3-O-(beta-D-N-acetyl-glucosaminopyranosyl)-32-nor- 24-methyllanost-8(9)-ene-30-oic acid, and E, (20S,22S,23R,24S)-3 beta,22, 23-trihydroxy-3-O-(beta-D-glucuronopyranosyl-(1-->2)-alpha-D- arabinopyranosyl-32-nor-24-methyllanost-8(9)-ene-30-oic acid, were isolated from an Ulosa sp. sponge. Their structures were determined by spectral methods and chemical transformations. Specific features of their structures are discussed.     

New secondary metabolites from the mangrove-derived fungus Aspergillus sp. AV-2

Chemical investigation of the mangrove-derived fungus Aspergillus sp. AV-2 following fermentation on solid rice medium led to the isolation of a new phenyl pyridazine derivative (1) and a new prenylated benzaldehyde derivative, dioxoauroglaucin (2), together with fourteen known compounds (3-16). Chemical structures of the new compounds were unambiguously determined based on HRESIMS and extensive 1D and 2D NMR spectroscopic analyses. Compounds 2-7, 8 and 13 were assessed for their antiproliferative activity against Caco-2 cell lines, where flavoglaucin (6) revealed the most potent cytotoxicity with IC₅₀ of 2.87 μM.     

Niche separation between colonizing and indigenous goatfish (Mullidae) along the Mediterranean coast of Israel

The present study assesses the resource partitioning between two Red Sea colonizers, the goldband goatfish Upeneus moluccensis and the brownband goatfish U. pori , and the two indigenous Mediterranean goatfishes, the red mullet Mullus barbatus and the striped mullet M. surmuletus , along the Mediterranean coast of Israel.
Niche separation was studied along three axes: habitat selection, feeding habits and spawning season. Habitat selection is the most significant parameter separating the species. The two colonizing species occupy a shallow habitat, U. pori dominating the primarily sandy bottom at 20–30 m and U. moluccensis at 40–50 m, at which depth the sea bottom becomes increasingly silty. Of the two indigenous species, M. barbatus is dominant in depths below 55 m, while M. surmuletus appears at low abundance in all depths.
Niche separation by feeding habits is much less evident. All four species feed primarily on macrurid crustaceans and thus the values of diet overlap are rather high (0·666≤ T ≤0·928). Prey size is not an important factor in niche separation. Young fishes (S.L>,115 mm) of all four species feed upon prey of similar size (20–160 mg). Among older individuals (S.L.>115 mm) three species continue to feed upon the same size prey, while U. moluccensis feeds upon considerably larger prey (600–2200 mg).
The difference between the spawning seasons of the colonizing vs indigenous species and consequent timing of benthic settling may contribute to niche separation.
The results of this study suggest that success in colonization by Red Sea goatfish may be due to the existence of unexploited niches in the eastern Mediterranean ecosystem.     

Novel bioactive bromopyrrole alkaloids from the Mediterranean sponge Axinella verrucosa

The Mediterranean sponge Axinella verrucosa has been investigated for its alkaloid composition and has been found to produce a complex mixture of bromopyrrole alkaloids. Along with the previously isolated compounds 5-18, four novel alkaloids of this class, compounds 1-4, have been isolated, and their structures established through spectroscopic methods. Compounds 1-4 were found to display neuroprotective activity against the agonists serotonin and glutamate in vitro.     

Stappia alba sp. nov., isolated from Mediterranean oysters

Three bacterial strains isolated from oysters recovered at the Spanish Mediterranean coast have been phenotypically and genetically characterized. The results of the phylogenetic analysis based on almost complete 16S rDNA sequences clustered all three strains together with 99.9% average sequence similarity and situated them in the neighbourhood of the genera Stappia, Roseibium and Pannonibacter, Stappia aggregata being their closest neighbour with sequence similarities between 98.8% and 98.9%. DNA-DNA hybridization experiments using DNA of strains 5OM6T and S. aggregata CECT 4269T as reference DNAs confirmed the independent status at species level of the oyster isolates. Phenotypically, they can be distinguished from the closest relatives by the ionic requirements, growth temperatures and use of carbon compounds. We propose these oyster strains constitute a new species of Stappia, for which the name Stappia alba sp. nov. has been chosen, and strain 5OM6T (= CECT 5095T = CIP 108402T) as its type strain.     

来自普哥滨珊瑚的一株Talaromyces sp.真菌的活性次生代谢产物

利用硅胶柱层析、制备型HPLC和重结晶等手段从普哥滨珊瑚分离的一株Talaromyces sp.真菌C21-1中筛选得到2个活性化合物,运用核磁共振、质谱和圆二色谱等技术鉴定这两个化合物分别为(R)-(-)-hydroxysydonic acid（1）和homodimeric WIN 64821（2）,补充完善了化合物2的核磁共振信号归属,并对化合物进行抗菌活性和乙酰胆碱酯酶抑制活性的测定,发现化合物1对白色假丝酵母Canidia albicans和耐甲氧基青霉素的金黄色葡萄球菌Methicillin-resistant Staphylococcus aureus（MRSA）具有一定的抑制作用,其最低抑菌浓度（MIC）分别为0.075mmol/L和0.2mmol/L,对副溶血弧菌Vibrio parahemolyticus的抑制活性较弱,在0.2mmol/L浓度下的抑制率为17%;化合物2最大浓度0.2mmol/L条件下对这3种菌均没有明显的抑制效果。化合物2表现出剂量依赖的乙酰胆碱酯酶抑制活性,0.5mmol/L时抑制率达到35.1%。     

Himeic acid A: a new ubiquitin-activating enzyme inhibitor isolated from a marine-derived fungus, Aspergillus sp

A new ubiquitin-activating enzyme (E1) inhibitor, himeic acid A, was isolated from a culture of marine-derived fungus, Aspergillus sp. The structure was determined by spectroscopic analysis. The formation of an E1-ubiquitin (Ub) intermediate was 65% inhibited by himeic acid A at the concentration of 50 microM, while two new related compounds, himeic acids B and C, showed little inhibitory activity even at 100 microM.     

海洋真菌杂色曲霉F62丁内酯类化合物研究

为了深入研究相似蜂海绵相关真菌杂色曲霉F62的活性代谢产物,采用硅胶柱、凝胶柱色谱和HPLC等分离手段对其大米固体发酵物的乙酸乙酯提取物进行分离,并利用质谱和核磁共振等现代波谱学技术对其结构进行鉴定,从中共得到6个丁内酯类化合物,分别为丁内酯Ⅰ(1)、丁内酯Ⅱ(2)、丁内酯Ⅲ(3)、丁内酯Ⅳ(4)、丁内酯Ⅶ(5)、Aspernolides A(6),其中化合物1在10μmol/L时表现出较强的抗炎活性,其IC50值为8.73μmol/L。     

Antifungal activity of altenusin isolated from the endophytic fungus Alternaria sp. against the pathogenic fungus Paracoccidioides brasiliensis

BackgroundAltenusin is a biphenyl derivative isolated from different species of fungi, which presents several biological activities.AimsWe report the antifungal activity of the altenusin isolated from the endophytic fungus Alternaria sp., against clinical isolates of Paracoccidioides brasiliensis, and its action on cell walls of P. brasiliensis and the nonpathogenic yeast Schizosaccharomyces pombe.MethodsIn vitro antifungal activity of altenusin was evaluated using the broth microdilution method against 11 strains of P. brasiliensis and one strain of S. pombe. The effects of the altenusin on the cell wall were estimated using the sorbitol protection assay.ResultsThe altenusin presented strong activity against P. brasiliensis with MIC values ranging between 1.9 and 31.2 μg/ml, and 62.5 μg/ml for S. pombe. Our results demonstrated that the MIC values for altenusin were increased for P. brasiliensis Pb18 and for S. pombe when the medium was supplemented with sorbitol. Additionally, S. pombe cells treated with altenusin were more rounded in shape than untreated cells.ConclusionsAltenusin showed activity against clinical strains of P. brasiliensis at the concentration tested, and this compound probably affects fungal cell walls. These findings suggest that altenusin could act through the inhibition of cell wall synthesis or assembly in P. brasiliensis and S. pombe, and could be considered as a lead compound for the design of new antifungals.     

Bioactive cytosporone derivatives isolated from the mangrove-derived fungus Dothiorella sp. ML002

Three new cytosporone derivatives dothiorelones K–M (1, 2 and 7), together with six known ones (3–6, 8 and 9) were isolated from the mangrove-derived fungus Dothiorella sp. ML002. Their structures were determined by comprehensive 1D, 2D NMR spectroscopic and HR-ESI-MS spectroscopic data. Compounds 1, 2 and 5 displayed inhibitory activities against α-glucosidase with the IC₅₀ values of 22.0, 77.9 and 5.4 μg/mL, respectively. Additionally, compounds 1, 2, and 5 also exhibited antibacterial activities against Staphylococcus aureus (ATCC 6538) with the same MIC values of 50 μg/mL, respectively. The results indicated that cytosporone derivatives will be useful to as diabetes control agents.     

A new lateral root growth inhibitor from the sponge-derived fungus Aspergillus sp. LS45

Two new γ-lactones, aspergilactones A (1) and B (2), were discovered along with two known compounds, annularin A (3) and pericoterpenoid A (4), from a culture of the sponge-associated fungus Aspergillus sp. LS45. The planar structures of 1–4 were characterized using comprehensive spectroscopic methods and comparison with literature data. The absolute configurations of 1 and 2 were determined by comparison of electronic circular dichroism (ECD) spectroscopic and optical rotation data with those of known analogues as well as calculated ECD analysis. Compounds 1–4 were tested in a variety of bioassays, and both 1 and 4 exhibited significant inhibition against the lateral root growth of Arabidopsis thaliana Columbia-0 at a concentration of 100 μM. In addition, the in vitro cytotoxic activities of 1–4 against six human cancer cell lines CCRF-CEM, K562, BGC823, AGS, HCT-116 and MDA-MB-231 were evaluated. Compound 4 showed moderate inhibitory effects on CCRF-CEM and K562 cancer cell lines with IC₅₀ values of 13.8 ± 1.6 and 12.9 ± 2.5 μM, respectively. However, compounds 1–4 did not show any notable AChE inhibitory activity in vitro.