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This article belongs to the Special Issue Marine Compounds and Inflammation II., Neurodegenerative diseases are age-related disorders caused by progressive neuronal death in different regions of the nervous system. Neuroinflammation, modulated by glial cells, is a crucial event during the neurodegenerative process; consequently, there is an urgency to find new therapeutic products with anti-glioinflammatory properties. Five new furanocembranolides (1-5), along with leptolide, were isolated from two different extracts of Leptogorgia sp., and compound 6 was obtained from chemical transformation of leptolide. Their structures were determined based on spectroscopic evidence. These seven furanocembranolides were screened in vitro by measuring their ability to modulate interleukin-1β (IL-1β) production by microglial BV2 cells after LPS (lipopolysaccharide) stimulation. Leptolide and compounds 3, 4 and 6 exhibited clear anti-inflammatory effects on microglial cells, while compound 2 presented a pro-inflammatory outcome. The in vitro results prompted us to assess anti-glioinflammatory effects of leptolide in vivo in a high-fat diet-induced obese mouse model. Interestingly, leptolide treatment ameliorated both microgliosis and astrogliosis in this animal model. Taken together, our results reveal a promising direct biological effect of furanocembranolides on microglial cells as bioactive anti-inflammatory molecules. Among them, leptolide provides us a feasible therapeutic approach to treat neuroinflammation concomitant with metabolic impairment., This research was funded by the Ministerio de Ciencia e Innovación (grants BFU2015-68149-R to MDG, SAF2016-77871-C2-1R to ICC, and SAF2009-0839 and RTA 2015-00010-C03-02 to MC) and by Consejería de Educación Junta Castilla y León (grant VA086G18 to MDG) and was cofinanced by European Regional Development Fund. MCG was supported by a University of Valladolid Ph.D. fellowship (call#2016). ARDM acknowledges support from Agustin de Betancourt Programme (Cabildo de Tenerife, TFinnova Programme supported by MEDI and FDCAN funds). A.B.G. would like to thank Convenio Universidad de Magallanes, programa interno PR-F2-01-CRN18-19 (Chile), and CSIC, project 2009CL0031, for financial support.

Se presenta una propuesta para el ajuste empírico de curvas correspondientes a transiciones de fase en mediciones obtenidas por Análisis Térmico Diferencial (ATD). La familia de funciones que se plantean para el ajuste se conoce como funciones Gumbel; estas funciones tienen características de asimetría que se asemejan a las de los picos típicos de ATD, a diferencia de funciones simétricas usualmente utilizadas para el ajuste de picos, como Gaussianas o Lorentzianas. El proceso de ajuste se llevó a cabo con mediciones de ATD realizadas en muestras de compuestos InxMn(1-x)Sb, los cuales exhiben la presencia de dos fases; InSb y MnSb, en las que dependiendo del valor de x se observan transiciones de fase que pueden ser o no simultáneas en temperatura. Al trabajar con curvas de transiciones de fase individuales, las funciones de Gumbel ajustan las curvas con coeficientes de correlación lineal (R2) superiores a 0.98, tanto para transiciones de fusión como para transiciones de solidificación, lo que evidencia el correcto ajuste de los datos experimentales. Se demuestra la valía de este tipo de ajustes al ser empleados en un sistema donde existen transiciones de fase simultáneas en temperatura, en este caso se muestra cómo, con las funciones de Gumbel, es posible separar estas señales superpuestas. Una vez separadas se podría tener acceso a información como la temperatura de transición o a la entalpía de transformación de cada uno de los compuestos presentes en la mezcla, algo que actualmente es muy complicado de hacer para señales simultáneas de ATD.

Eighteen new oxysterols have been isolated from a previously undescribed octocoral collected from the eastern Pacific of Panama. Their structures were determined based on spectroscopic evidence. The absolute configuration was established by derivatization with (R)- and (S)-MPA. Antimicrobial and antileishmanial effects were evaluated., This work was supported by the Ministerio de Ciencia e Innovación (BIO2007-61745 and SAF2009-0839). F. C. acknowledges financial support from Programa JAE-Pre (CSIC). ARDM acknowledges funding from IMBRAIN project (FP7-REGPOT2012-CT2012-31637-IMBRAIN).

In this work, we introduce an opto-geometric parameter for the morphologic characterization of cell populations during their early adhesion process. Using measurements for a cell population of the maximal optical phase for each cell and its substrate-contact-surface, we show, experimentally, that a relationship exists between these variables. This connection is primarily associated with morphological cell characteristics. It is also shown that using the relationship obtained above, we can derive a morphological parameter, which, for the cell populations studied, results in a monodisperse Gaussiansize distribution, which would allow for the use of regular statistical variables. This result is in total contrast with the polydisperse distribution obtained if only the contact surface area between cell and substrate is used. In addition, optical phase measurements where accomplished by phase shifted interferometry using a Mirau-type interference microscope. The cellular system studied consisted of Osteoblast-like cells, plated on 316VM medical-grade stainless steel polished surfaces. These cell populations were studied within the same culture conditions of cell type, plating time and substrate roughness conditions. The existence of a relationship between maximal optical phase and substrate contact area agrees entirely with the accepted spreading model for cell adhesion; in particular, considering the close link between the optical phase time change and cell thickness reduction.

Nine new cembranoids 1–9 containing an α–methylene–γ–butyrolactone together with the known diterpenes 10–15 have been isolated from a crude extract of Eunicea sp. and their structures were established by spectroscopic methods. The proliferative effect of six of these compounds on insulin-producing cells (beta–cells) was evaluated., This work was funded by the Ministerio de Ciencia e Innovación (SAF2009-0839 and RTA 2015-00010-C03-02). ARDM acknowledges financial support from Cabildo de Tenerife and Agustin de Betancourt Programme 2016. GP acknowledges a fellowship from Programa JAE-Pre (CSIC).

This article belongs to the Special Issue Progress on Marine Natural Products as Lead Compounds., Two new chloro-furanocembranolides (1, 2) and two new 1,4-diketo cembranolides (3, 4) were isolated from the crude extract of Leptogorgia sp. together with a new seco-furanocembranolide (5) and the known Z-deoxypukalide (6), rubifolide (7), scabrolide D (8) and epoxylophodione (9). Their structures were determined based on spectroscopic evidence. Four compounds: 1, 2, 7 and 8 were found to activate the proliferation of pancreatic insulin-producing (beta) cells., This work was supported by the Ministerio de Ciencia e Innovación (SAF2009-0839 and RTA 2015-00010-C03-02). ARDM acknowledges funding from IMBRAIN project (FP7-REGPOT-2012-CT2012-31637-IMBRAIN) and from Cabildo de Tenerife (Agustín de Betancourt Programme). A.B.G. would like to thank Convenio Universidad de Magallanes (Chile) and CSIC, project 2009CL0031, for financial support.

This work was supported by the Spanish Ministerio de Ciencia e Innovacion (MICINN) (SAF2009‐0839). F. C. acknowledges financial support from the Programa JAE‐Pre (CSIC). A.R. D.‐M. acknowledges funding from the IMBRAIN project (FP7‐REGPOT‐2012‐CT2012‐31637‐IMBRAIN). The Government of Panama granted permission for the collection of the samples. C. C. is supported by a “Waxweiler grant for cancer prevention research” from the Action LIONS Vaincre le Cancer. This work was also supported by Televie Luxembourg, the Recherche Cancer et Sang foundation, and the Recherches Scientifiques Luxembourg association. The authors thank the Een Haerz fir Kriibskrank Kanner association and the Action LIONS Vaincre le Cancer for generous support. Further support was received from the European Union (EU) (ITN “RedCat” 215009 and Interreg IVa project “Corena”). M. D. was supported by the Korean National Research Foundation (NRF), MEST [Tumor Microenvironment Global Core Research Center (GCRC), grant number 2012‐0001184].

Ptilonines A−F, pyranosylmagellanicus D−E and magellenediol are previously undescribed acetogenins isolated from the red alga Ptilonia magellanica. Their structures were determined from spectroscopic evidence. The absolute configuration of the known pyranosylmagellanicus A, was established by derivatization with (R)− and (S)−α−methoxy −α−phenylacetic acids (MPA). Ptilonines exhibit an unusual halogenation pattern, that may confer evolutionary advantages to Ptilonia magellanica, for which a biogenetic origin is proposed. The antimicrobial effect of some of these compounds was evaluated., This work was supported by the Ministerio de Ciencia e Innovación (SAF2009-0839 and RTA 2015-00010-C03-02). ARDM acknowledges funding from IMBRAIN project (FP7-REGPOT-2012-CT2012-31637-IMBRAIN). A.B.G. would like to thank Convenio Universidad de Magallanes (Chile) and CSIC, project 2009CL0031 and Programa PR-F2-03-CRN16 for financial support.

[EN] The marine actinobacterium AMS370, identified as Salinispora arenicola by 16S rRNA amplified gene comparison, was isolated from sediments of the Gulf of California, Mexico. From its semi-polar extract, 8 known compounds were isolated: 4-Hydroxy-phenyl acetic acid (1), 5-Methyl-2-methylene-2,3-dihydro-1H-pyrimidin-4-one (2), 1H-Pyrimidine-2,4-dione (3), 3-amino-5-hydroxy-benzoic acid (4), 2-(4-Amino-imidazol-[4,5-d]pyridazin-1-yl)-5-hydroxymethyl-4-methyl-tetrahydro-furan-3-ol (5), 3-(4-Hydroxy-phenyl)-acrylic acid methyl ester (6), 3-Benzyl-6-isobutyl-piperazine-2,5-dione (7) and 5,8-epidioxy-(22E,24R)-ergosta-6,22-dien-3-ol (Ergosterol peroxide) (8). The chemical identification was performed by comparison of their NMR spectra against the NMR spectra of the original compounds. This is the first time that compound 4 is reported as a natural product obtained from the Salinispora genus. The crude extract and all the fractions obtained were tested for antibiotic activity against Bacillus cereus, Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Proteus mirabilis, Staphylococcus aureus, Salmonella sp. and antifungic activity against Candida albicans. Also, breast cancer (MCF-7), cervical cancer (HeLa) and colorectal cancer cell lines (HCT-116) were tested to determine their cytotoxic activity. Only the semi-polar crude extract and its fractions 5.1 and 5.2 were active against Klebsiella pneumoniae and Staphylococcus aureus., [ES] La actinobacteria marina AMS370, identificada mediante comparación de las secuencias del gen 16S del ARNr como Salinispora arenicola, fue aislada a partir de sedimento del Golfo de California, México. De su extracto semi-polar, se aislaron 8 compuestos conocidos: ácido-4-Hidroxi-fenil acético (1), 5-Metil-2-metilen-2,3-dihidro-1H-pirimidin-4-ona (2), 1H-Pirimidin-2,4-diona (3), ácido-3-amino-5-hidroxi-benzoico (4), 2-(4-Amino-imidazol-[4,5-d]piridazin-1-il)-5-hidroximetil-4-metil-tetrahidro -furan-3-ol (5), Acrilato de 3-(4-Hidroxi-genil)-metilo (6), 3-Bencil-6-isobutil-piperazin-2,5-diona (7) y 5,8-epidioxi-(22E,24R)-ergosta-6,22-dien-3-ol (Peróxido de Ergosterol) (8). La identificación química fue realizada mediante comparación de sus espectros de RMN con los espectros de los compuestos originales. Ésta sería la primera ocasión que el compuesto 4 se reporta como un producto natural a partir del género Salinispora. El extracto crudo y todas sus fracciones fueron ensayadas contra Bacillus cereus, Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Proteus mirabilis, Staphylococcus aureus, Salmonella sp. y Candida albicans para probar su actividad antibiótica y antifúngica en el caso de la última especie. Asimismo se evaluó su actividad citotóxica frente a las líneas celulares de cáncer de mama (MCF-7), cervicouterino (HeLa) y colorectal (HCT-116). Solamente el extracto crudo semipolar y las fracciones 5.1 y 5.2 resultaron activas contra Klebsiella pneumoniae y Staphylococcus aureus., We thank the financial support provided by the UABC through the XV Internal Assembly, and the Consejo Nacional de Ciencia y Tecnología (México) 2011 Basic Science Grant No. 168484 and by the Ministerio de Ciencia e Innovación (SAF2009-08039; SAF2010-16858). We also thank the CONACYT for the pre-doctorate fellowship given to FCM (No. 206455) and to AMIM (No. 252250).

The cembranoid 1 and the furanocembranolides 2–4 along with the known pukalide were isolated from Leptogorgia sp. and their structures determined spectroscopically. The 1,4-diketo-cembranoid 1 follows an oxidation pattern of C-18 that reinforces the concept of oxidation profile of C-18 as taxonomical marker for octocorals. The co-occurrence within a species of furanocembranolide/1,4-diketo-cembranoid congeners 1/2–4 raises the question about which one is the biogenetic precursor. A biogenetic pathway is proposed.

Gomerolactones A–D along with the known majusculone, obtusol, and elatol were isolated from Laurencia majuscula, and their structures were determined spectroscopically. With the aid of Pirkle's reagent at low temperature, NMR spectroscopy was used to determine the absolute configuration at the ring closure carbon atom of a α-alkylidene-γ-lactone and an α-alkylidene-δ-lactone unit embedded in the chamigrene network of compounds 1 and 2, respectively. The absolute stereochemistry of compounds 3 and 4 was determined by X-ray analysis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Tanzawaic acids M (1), N (2), O (3) and P (4) and the known tanzawaic acids B (5) and E (6), have been isolated from an extract of a cultured marine-derived fungus (strain CF07370) identified as a member of the genus Penicillium. The structures of 1–4 were determined based on spectroscopic evidence. The antimicrobial and cytotoxic activities of compounds 1–6 were evaluated.

This work was supported by the Spanish Ministerio de Ciencia e Innovacion (MICINN) (SAF2009‐0839). F. C. acknowledges financial support from the Programa JAE‐Pre (CSIC). A.R. D.‐M. acknowledges funding from the IMBRAIN project (FP7‐REGPOT‐2012‐CT2012‐31637‐IMBRAIN). The Government of Panama granted permission for the collection of the samples. C. C. is supported by a “Waxweiler grant for cancer prevention research” from the Action LIONS Vaincre le Cancer. This work was also supported by Televie Luxembourg, the Recherche Cancer et Sang foundation, and the Recherches Scientifiques Luxembourg association. The authors thank the Een Haerz fir Kriibskrank Kanner association and the Action LIONS Vaincre le Cancer for generous support. Further support was received from the European Union (EU) (ITN “RedCat” 215009 and Interreg IVa project “Corena”). M. D. was supported by the Korean National Research Foundation (NRF), MEST [Tumor Microenvironment Global Core Research Center (GCRC), grant number 2012‐0001184].

Tanzawaic acids M (1), N (2), O (3) and P (4) and the known tanzawaic acids B (5) and E (6), have been isolated from an extract of a cultured marine-derived fungus (strain CF07370) identified as a member of the genus Penicillium. The structures of 1–4 were determined based on spectroscopic evidence. The antimicrobial and cytotoxic activities of compounds 1–6 were evaluated., This work was supported by the Ministerio de Ciencia e Innovación SAF2009–0839. F. C. acknowledges financial support from Programa JAE-Pre (CSIC). ARDM acknowledges funding from the IMBRAIN project (FP7-REGPOT-2012-CT2012–31637-IMBRAIN). CC is supported by a “Waxweiler grant for cancer prevention research” from the Action Lions “Vaincre le Cancer”, Luxembourg. This work was supported by Télévie Luxembourg, the “Recherche Cancer et Sang” foundation and “Recherches Scientifiques Luxembourg” association. The authors thank the “Een Häerz fir Kriibskrank Kanner” association and the Action Lions “Vaincre le Cancer” for generous support. MD is supported by the National Research Foundation (NRF) by the MEST of Korea for Tumor Microenvironment Global Core Research Center (GCRC) grant, [grant number 2012–0001184].

The rearranged compound 1, the regular 2 and 3 and the degraded 4 are novel bisabolene-type metabolites that along with the known compounds caespitol, 8-acetylcaespitol, caespitane, caespitenone, laucapyranoid A, and furocaespitane have been isolated from the sea hare Aplysia dactylomela. The structures of these compounds were determined on the basis of spectroscopic evidence. The irregular network of 1 suggested that the halogenated epoxide 6 is a key intermediate for a unified biogenetic pathway of naturally occurring marine algal bisabolene-type metabolites.

4 pages, 2 figures, 1 table, 1 scheme.-- Available online Dec 12, 2005.-- Supporting information (10 pages) available at: http://www.wiley-vch.de/contents/jc_2046/2006/o200500775_s.pdf, Side-chain-oxidized C-28-sterol 1 and one new pregnane metabolite 2 were isolated from eastern Pacific Muricea spp. The C-24(28)-epoxide functionality is a key intermediate in the C-24-dealkylation mechanism of the conversion of phytosterol to cholesterol by phytophagous insects. Certain marine invertebrates share this dealkylation pathway; however, such a key epoxide feature has not yet been found in a naturally occurring sterol from marine invertebrates. The unusual oxidation pattern of the side chain of 1 encourages speculation about its biogenesis and converts this non-zooxanthellate gorgonia into an interesting candidate organism for biosynthetic studies on C-24-dealkylation of phytosterols in octocorals. The (22S)-22-hydroxy group, after 24-dealkylation of 1, may be an advantageous functionalization in the side-chain cleavage to C-21-pregnane steroids in Muricea spp., This work was supported by the Ministerio de Educación y Ciencia (PPQ2002-02494), and the DGUI of the Canary Islands Government (PI2002/044). M. L. acknowledges MECESUP MAG0002, Chile, for financial support. The STRI provided support and facilities.

5 pages, 4 figures, 1 table.-- Printed version published Oct 3, 2005., Three naturally occurring pyranosyl-like polyhalogenated metabolites 1–3 as well as their likely biogenetic precursor, the linear compound 4, have been isolated from the red alga Ptilonia magellanica. They are the first compounds within the genus that incorporate chlorine in their network. Compound 3 have structural features reminiscent of the universal chemical signal AI-2 (autoinducer-2) for bacterial communication., This work was supported by the Ministerio de Educación y Ciencia (PPQ2002-02494, REN2002-10485-E/ANT), and the Gobierno de Canarias DGUI (PI2002/044). M.L. acknowledges MECESUP MAG0002, Chile, for financial support.

A biogenetically interesting halogen-devoid metabolite chamigrenelactone 1, with a high oxygen-content, has been isolated from Laurencia obtusa from Isla Grande (Caribbean Panama). Its structure and stereochemistry were determined on the basis of spectral studies.

Two novel sesterterpenes 1 and 2 have been isolated from the Antarctic sponge Suberites caminatus. Their structures and relative stereochemistries were determined by spectroscopic methods. Compound 1 features a novel structural type of suberitane network, and an epimer of compound 2 seems to be the biogenetic precursor of 1 and suberitenones A and B. The exclusive prevalence of suberitane-derived sesterterpene metabolites in species of Suberites suggests that this skeleton may be a chemical marker of the genus.

5 pages, 3 tables, 1 chart.-- PMID: 12428955 [PubMed].-- Printed version published Nov 20, 2002., Supporting information available: Table showing the phytotoxic effects of compounds 11-13 on barley and tomato leaves.-- Available at: http://pubs.acs.org/doi/suppl/10.1021/jf025857p?cookieSet=1, In this work the antifeedant effects of the halogenated monoterpenes 1−13 were tested against several divergent insect species. These compounds have been isolated from Plocamium cartilagineum (6 was isolated as an acetyl derivative), except for 4, which was isolated from Pantoneura plocamioides. We have also included the semisynthetic derivatives 1a, 2a, and 7. Compounds 1, 1a, 2, 4, 5, 7, 8−10, and 13 were antifeedants against Leptinotarsa decemlineata with varying potencies. The aphids Myzus persicae and Ropalosiphum padi were strongly deterred in the presence of compounds 2, 12, and 13. This effect was correlated with the electronic recording of their probing behavior. Compounds 2 and 12 were toxic to L. decemlineata and had selective cytotoxicity to insect-derived Sf9 cells. None of the tested compounds showed phytotoxic effects. The antifeedant and cytotoxic effects of these compounds were compared with those of the polyhalogenated insecticide γ-hexachlorocyclohexane (lindane)., A.R.D.-M., M.C., O.S., and A.G. acknowledge I3P-CSIC (predoctoral and postdoctoral), AECI (predoctoral), and MEC/Contrato de Reincorporación Fellowships. This work was partially supported by Convenio CSIC-U.Chile and Grants FONDECYT 1990935, Instituto Antártico Chileno (INACH), MCYT-Spain (BQU2001-1505; PPQ2002-02494), and CYTED IV.13.

4 pages, 2 figures, 1 table, 1 scheme.-- Printed version published Sep 2, 2002., A unique diterpene 1, was isolated from the altiplane Andean plant Azorella madreporica Clos (Apiaceae). The structure and stereochemistry were established by spectral methods and molecular mechanics calculations. The compound possesses a novel hydrocarbon skeleton for which we suggest the name madreporane., The structure and stereochemistry for madreporanone are described., This work was supported by the Ministerio de Ciencia y Tecnología (MCYT, Spain), FEDER (EU), FONDECYT: 1011068 (Chile), Subdirección General de Cooperación Internacional, Program of Cooperation between the Consejo Superior de Investigaciones Científicas (CSIC, Spain) and CONICYT (Chile), and DI of the Universidad de Antofagasta.

4 pages, 1 figure, 2 tables.-- PMID: 11975508 [PubMed].-- Printed version published Apr 26, 2002., Three new minor linear polyhalohydroxylated marine monoterpenes, plocamenols A−C (1−3), have been isolated from the red alga Plocamium cartilagineum. The structure and relative stereochemistry of these compounds were determined on the basis of spectroscopic evidence., This work was supported by Programa Antártico Español (MCYT), FEDER (projects: 1FD97-0348- C03-03), FONDECYT (1990935), Subdirección General de Cooperación Internacional, and the Program of Cooperation between the Consejo Superior de Investigaciones Científicas (CSIC, Spain)-Universidad de Chile. A.R.D.-M. acknowledges a fellowship from the CICYT.

Fungi occupy an important ecological niche in the marine environment, and marine fungi possess an immense biotechnological potential. This study documents the fungal diversity associated with 39 species of sponges and determines their potential to produce secondary metabolites capable of interacting with mammalian G-protein-coupled receptors involved in blood pressure regulation. Total genomic DNA was extracted from 563 representative fungal strains obtained from marine sponges collected by SCUBA from the Caribbean and the Pacific regions of Panama. A total of 194 operational taxonomic units were found with 58 % represented by singletons based on the internal transcribed spacer (ITS) and partial large subunit (LSU) rDNA regions. Marine sponges were highly dominated by Ascomycota fungi (95.6 %) and represented by two major classes, Sordariomycetes and Dothideomycetes. Rarefaction curves showed no saturation, indicating that further efforts are needed to reveal the entire diversity at this site. Several unique clades were found during phylogenetic analysis with the highest diversity of unique clades in the order Pleosporales. From the 65 cultures tested to determine their in vitro effect on angiotensin and endothelin receptors, the extracts of Fusarium sp. and Phoma sp. blocked the activation of these receptors by more than 50 % of the control and seven others inhibited between 30 and 45 %. Our results indicate that marine sponges from Panama are a “hot spot” of fungal diversity as well as a rich resource for capturing, cataloguing, and assessing the pharmacological potential of substances present in previously undiscovered fungi associated with marine sponges., The authors thank the National Secretariat of Science and Technology of the Republic of Panama for financial support by grants of international collaboration number COL08-014 and COL10-070 and by a partnership program between the Organization for the Prohibition of Chemical Weapons (The Hague, Netherlands) and the International Foundation for Science (Stockholm, Sweden).

The diversity of sponge-associated fungi has been poorly investigated in remote geographical areas like Antarctica. In this study, 101 phenotypically different fungal isolates were obtained from 11 sponge samples collected in King George Island, Antarctica. The analysis of ITS sequences revealed that they belong to the phylum Ascomycota. Sixty-five isolates belong to the genera Geomyces, Penicillium, Epicoccum, Pseudeurotium, Thelebolus, Cladosporium, Aspergillus, Aureobasidium, Phoma, and Trichocladium but 36 isolates could not be identified at genus level. In order to estimate the potential of these isolates as producers of interesting bioactivities, antimicrobial, antitumoral and antioxidant activities of fungal culture extracts were assayed. Around 51 % of the extracts, mainly from the genus Geomyces and non identified relatives, showed antimicrobial activity against some of the bacteria tested. On the other hand, around 42 % of the extracts showed potent antitumoral activity, Geomyces sp. having the best performance. Finally, the potential of the isolated fungi as producers of antioxidant activity seems to be moderate. Our results suggest that fungi associated with Antarctic sponges, particularly Geomyces, would be valuable sources of antimicrobial and antitumoral compounds. To our knowledge, this is the first report describing the biodiversity and the metabolic potential of fungi associated with Antarctic marine sponges., This work was supported by FONDECYT grant 11090192, Instituto Antártico Chileno (INACH) and “Programa Bicentenario de Ciencia y Tecnología” (Chile) project PDA13.

Isothermal titration calorimetry (ITC) is based on a simple titration of one ligand with another and the small heat changes caused by the molecular interaction are detected. From one ITC experiment the complete set of thermodynamic parameters of binding including association and dissociation constants as well as changes in enthalpy, entropy, and free energy can be derived. Using this technique almost any type of molecular interaction can be analyzed. Both ligands are in solution, and there is no need for their chemical derivatization. There are no limits as to the choice of the analysis buffer, and the analysis temperature can be set between 4 and 80 °C. This technique has been primarily applied to study the interaction between various proteins of Pseudomonas with small molecule ligands. In addition, ITC has been used to study the binding of Pseudomonas proteins to target DNA fragments.

A primary driving force during bacterial evolution was the capacity to access compounds necessary for growth and survival. Since the species of the genus Pseudomonas are characterized by metabolic versatility, these bacteria have developed chemotactic behaviors towards a wide range of different compounds. The specificity of a chemotactic response is determined by the chemoreceptor, which is at the beginning of the signaling cascade and to which chemoattractants and chemorepellents bind. The number of chemoreceptor genes of Pseudomonas species is significantly higher than the average number in motile bacteria. Although some of the receptors have been annotated with a function, the cognate signal molecules for the majority of them still need to be identified. Different qualitative and quantitative methods are presented that can be used to study flagellum-mediated taxis.

Pantoneurotriols 1a and 2a are acyclic polyoxygenated monoterpenes isolated from the Antarctic endemism Pantoneura plocamioides together with compounds 3 and 4. The stereochemistries of these compounds were established by spectroscopic methods and pantoneurotriols have been proposed as biogenetic precursors of pantofuranoids, uncommon monoterpenes isolated from the same species. It was interesting to find compounds 4 and 5, metabolites first isolated from Plocamium cartilagineum, in a species belonging to a different order such as P. plocamioides.

Six new polyoxygenated marine monoterpenes have been isolated from the Antarctic alga Pantoneura plocamioides. The structure and relative stereochemistry of these compounds, denominated pantopyranoids A-C (1-3), and pantoisofuranoids A-C (4-6) were determined on basis of spectroscopic evidence.

(3Z)-13-epipinnatifidenyne 1, a novel C15 acetogenin, has been isolated together with others five known compounds from the red alga Laurencia claviformis, a species endemic to Easter Island. The structure of 1 was elucidated based on spectral analysis, including 2D NMR spectroscopy.

In this work organic products were isolated and identified from a marine Bacillus sp. which presented growth inhibition of the pandemic strain of V. parahaemolyticus. The inhibitory products were extracted and characterized by spectroscopic and spectrometric techniques. Purification of the active products revealed five different diketopiperazines, which were compared with standards from high-performance liquid chromatography (HPLC). Although the diketopiperazines is not a finding of a new metabolite, the interested point or novelity of this work is the ability of diketopiperazines to inhibit the growth of pandemic strain of V. parahaemolyticus. We suggest the possibility of using this compound to reduce the growth and control the proliferation of pathogenic clones of V. parahaemolyticus that cause several problems in aquaculture industry.

Dactylomelatriol (1), obtained from the sea hare Aplysia dactylomela, is the first naturally occurring omphalane-derived sesquiterpene from the marine environment. From this species the known chamigrene and modified bisabolene sesquiterpenes 2-6 were also isolated. The structure and relative configuration of 1 were established by spectroscopic evidence. Its chemical structure is related to omphalic acid, the unique terrestrial-derived omphalane sesquiterpene isolated from a liverwort. A biogenetic route for this compound is proposed. The antimicrobial activities of compounds 1-6 were evaluated against a panel of microorganisms., This work was supported by the Ministerio de Ciencia e Innovación (BIO2007-61745, SAF2009-08039, SAF2010-16858) and DGUI Gobierno de Canarias (PIO42005, PUB2005/030). We gratefully acknowledge A. Corrales for her technical support of this project.

3 pages, 3 figures, 1 table.-- PMID: 12088448 [PubMed].-- Printed version published Jun 28, 2002., Supporting information (2 pages) available at: http://pubs.acs.org/doi/suppl/10.1021/np010580t, Two new sesquiterpenes belonging to a novel oxacyclic structural type of chamigrene skeleton, oxachamigrene (1) and 5-acetoxyoxachamigrene (2), have been isolated from the red alga Laurencia obtusa. The structures of the compounds were determined on the basis of spectroscopic evidence. A biogenetic route for these metabolites has been proposed., This work was supported by Ministerio de Ciencia y Tecnología (MCYT), FEDER (project 1FD97-0348- C03-03), Subdirección General de Cooperación Internacional, Program of Cooperation between the Consejo Superior de Investigaciones Científicas (CSIC, Spain)-Universidad de Chile and the collaboration of CEBIMAR of Cuba. I.B. acknowledges a grant from the CICYT.

Six guaiane sesquiterpenes recurvatiane A-F, including the previously known recurvatiane E and xanthomicrol, were isolated from the Andean Perezia recurvata and their structures determined by spectroscopic evidence. The absolute stereochemistry of recurvatiane A was established by derivatization with (R)- and (S)-α-methoxy-α-phenylacetic acids (MPA). The suite of guaiane-based metabolites here reported, which we have named recurvatianes A-F, provide an example of a pathway by which molecular diversity is generated by the occurrence of specific oxidation reactions in the late biosynthetic steps of the frame structure., This work was supported by the Ministerio de Educación y Ciencia (BIO2007-61745, SAF2009-08039, SAF2010-16858). A.R.D.-M. would like to thank Programa JAE-Doc (CSIC) for financial support.

Two new steroids (1 and 2) and the known pregna-1,4,20-trien-3-one (3) have been isolated from the Pacific octocoral Carijoa multiflora. Compound 1 possesses a novel spiropregnane-based steroidal skeleton. The photochemical transformation of 3 into 1 allowed the assignment of the absolute configuration at C-10 of 1. The antibacterial activities of compounds 1 and 3 were evaluated against a panel of bacterial strains., his work was supported by the Ministerio de Ciencia e Innovación (BIO2007-61745, SAF2009-08039, SAF2010-16858). A.R.D.-M. acknowledges financial support from Programa JAE-Doc (CSIC).

Two new asterosaponins, validosides A and B, were isolated from the butanolic extract of the starfish Odontaster validus and their structures established as (24S)‐24‐O‐[2,4‐di‐O‐methyl‐β‐xylopyranosyl‐(1→2)‐α‐arabinofuranosyl]‐5α‐cholestane‐3β,4β,6α,8,15β,24‐hexaol 6‐O‐sodium sulfate (1) and (24S)‐24‐O‐(3‐O‐methyl‐β‐xylopyranosyl)‐5α‐cholestane‐3β,6α,8,15β,24‐pentaol 2′‐O‐sodium sulfate (2) on the basis of extensive spectroscopic investigations and chemical correlations. Validoside A and B are extremely rarely occurring saponins due to the presence of a sulfated group at C‐6 of the aglycone in 1 and at C‐2′ of a pyranose in 2. The absolute configuration at C‐24 was found to be S by the application of the Trost‐Mosher methodology. Copyright © 1993 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim

A new halogenated sesquiterpene has been isolated, together with five known compounds, from the red alga Laurencia claviformis, a species endemic to Easter Island. The structures were elucidated based on spectral analysis. The effect of these compounds on the inhibition of cytokinesis in the sea urchin Tetrapygus niger embryos was studied.

A bromo sesquiterpene, bromocyclococanol 1 , containing fused cyclopropane–cyclopentane rings leading a novel carbon skeleton has been isolated from the red alga Laurencia obtusa. The structure and stereochemistry were established by spectroscopic evidence and biogenetic considerations. A biogenetic route for this compound has also been proposed

A unique diterpene 1, was isolated from the altiplane Andean plant Azorella madreporica Clos (Apiaceae). The structure and stereochemistry were established by spectral methods and molecular mechanics calculations. The compound possesses a novel hydrocarbon skeleton for which we suggest the name madreporane.

A new asterosaponin, named santiagoside (1), has been isolated from the Antarctic starfish Neosmilaster georgianus and, its structure elucidated on the basis of extensive spectroscopic experiments and chemical correlations. Santiagoside is the first asterosaponin possessing a tetrasaccharide sugar chain and a 1,4-disubstituted glucose unit.

The cembranoid 1 and the furanocembranolides 2–4 along with the known pukalide were isolated from Leptogorgia sp. and their structures determined spectroscopically. The 1,4-diketo-cembranoid 1 follows an oxidation pattern of C-18 that reinforces the concept of oxidation profile of C-18 as taxonomical marker for octocorals. The co-occurrence within a species of furanocembranolide/1,4-diketo-cembranoid congeners 1/2–4 raises the question about which one is the biogenetic precursor. A biogenetic pathway is proposed.

2 pages, 1 figure, 1 table.-- Article in press., Supporting information available: Figures and NMR spectra of compounds 1 and 2.-- Available at: http://pubs.acs.org/doi/suppl/10.1021/np9000976, Pronuciferine N-oxide (1), a proaporphine N-methyl-N-oxide alkaloid, along with the parent alkaloid pronuciferine (2) were isolated from Berberis coletioides. The structure of the new compound was determined by spectroscopic evidence. Compound 1 is the first naturally occurring proaporphinoid alkaloid with an N-oxide functionality., This work was supported by Universidad de Magallanes and Ministerio de Educación y Ciencia (BIO2007-61745, SAF2006-03004).

Bioassay-guided purification of an ethanolic extract of Cystoseira myrica against HEPG-2 (liver) and HCT116 (colon) human cancer cell lines led to the isolation of 3-keto-22-epi-28-nor-cathasterone, 1 and cholest-4-ene-3,6-dione, 2. This finding allowed us to report for the first time that a brassinosteroid-related metabolite occurs in seaweed. These compounds showed activity in the range of 12.38–1.16 μM with selective activity of compound 2 to liver cancer cell lines.