molecules-logo

Journal Browser

Journal Browser

Special Issue "Bioactive Marine Natural Products: Towards Understanding of the Physiology and Ecology of Marine Life"

A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Natural Products Chemistry".

Deadline for manuscript submissions: 31 December 2020.

Special Issue Editor

Prof. Dr. Ryuichi Sakai
Website
Guest Editor
Faculty and Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Japan
Interests: marine natural products; biological activity; biological function; chemical ecology; metabolomics; biosynthesis; biomineralization; neuroactive; glutamate receptor; hematopoietic cytokine; lectin; bioactive protein; drug delivery; toxin; polyamine; GPCR; membrane; anticancer; antiviral

Special Issue Information

Dear Colleagues,

Marine organisms often contain metabolites that differ clearly from their terrestrial counterparts both structurally and in terms of function, mainly because they live in watery milieu with high salinity and form diverse ecosystems reflecting their living environments.

Fifty years of studies on marine natural products have proven that marine organisms have acquired the unique metabolic ability to produce a variety of biologically active compounds. In many cases, the symbiotic relationship between host and microorganisms play a role in production. However, the actual producers, roles in the producing organisms and marine ecosystems, and actual target molecules of the bioactive metabolites are not well understood, due mainly to the difficulty in designing experiments with hard-to-culture marine species.

Recent advances in genomics and metabolomics (the -omics approach) and other new techniques now allow us to deal with such questions that have been inaccessible before.

This Special Issue invites original research and reviews describing marine metabolites in light of their isolation and structure determination, biological activities, function, producing organisms, roles, biosynthesis, modes of action, and chemical ecology. Studies and observations that generate new hypotheses are especially welcome. Synthetic works aiming to solve biological questions are also invited.

Prof. Dr. Ryuichi Sakai
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Molecules is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2000 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Marine natural products
  • Chemical ecology
  • Biosynthesis
  • Bioactive metabolites
  • Mode of action
  • Physiological roles
  • Ecosystem
  • Symbiosis
  • Toxin

Published Papers (4 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Open AccessArticle
Pectenovarin, A New Ovarian Carotenoprotein from Japanese Scallop Mizuhopecten yessoensis
Molecules 2020, 25(13), 3042; https://doi.org/10.3390/molecules25133042 - 03 Jul 2020
Abstract
The scallop Mizuhopecten yessoensis accumulates carotenoids in the ovary during the maturation stage. Its conspicuous pink color implies the presence of carotenoprotein. However, the carotenoprotein from the scallop ovary has never been isolated and characterized, probably due to its instability and complexity. Here, [...] Read more.
The scallop Mizuhopecten yessoensis accumulates carotenoids in the ovary during the maturation stage. Its conspicuous pink color implies the presence of carotenoprotein. However, the carotenoprotein from the scallop ovary has never been isolated and characterized, probably due to its instability and complexity. Here, we developed an extraction and isolation procedure for the carotenoprotein by employing a basic buffer containing potassium bromide to facilitate its efficient extraction from the ovary, and we succeeded in obtaining the carotenoprotein, termed pectenovarin. The carotenoid composition of the pectenovarin was similar to that of the ovary. The N-terminal and internal amino acid sequences of pectenovarin showed a high similarity to those of vitellogenin, the precursor of egg yolk protein under analysis. Full article
Show Figures

Graphical abstract

Open AccessArticle
Isolation, Structure Determination, and Synthesis of Cyclic Tetraglutamic Acids from Box Jellyfish Species Alatina alata and Chironex yamaguchii
Molecules 2020, 25(4), 883; https://doi.org/10.3390/molecules25040883 - 17 Feb 2020
Abstract
Cubozoan nematocyst venoms contain known cytolytic and hemolytic proteins, but small molecule components have not been previously reported from cubozoan venom. We screened nematocyst extracts of Alatina alata and Chironex yamaguchii by LC-MS for the presence of small molecule metabolites. Three isomeric compounds, [...] Read more.
Cubozoan nematocyst venoms contain known cytolytic and hemolytic proteins, but small molecule components have not been previously reported from cubozoan venom. We screened nematocyst extracts of Alatina alata and Chironex yamaguchii by LC-MS for the presence of small molecule metabolites. Three isomeric compounds, cnidarins 4A (1), 4B (2), and 4C (3), were isolated from venom extracts and characterized by NMR and MS, which revealed their planar structure as cyclic γ-linked tetraglutamic acids. The full configurational assignments were established by syntheses of all six possible stereoisomers, comparison of spectral data and optical rotations, and stereochemical analysis of derivatized degradation products. Compounds 13 were subsequently detected by LC-MS in tissues of eight other cnidarian species. The most abundant of these compounds, cnidarin 4A (1), showed no mammalian cell toxicity or hemolytic activity, which may suggest a role for these cyclic tetraglutamates in nematocyst discharge. Full article
Show Figures

Graphical abstract

Open AccessArticle
Biologically Active Echinulin-Related Indolediketopiperazines from the Marine Sediment-Derived Fungus Aspergillus niveoglaucus
Molecules 2020, 25(1), 61; https://doi.org/10.3390/molecules25010061 - 23 Dec 2019
Abstract
Seven known echinulin-related indolediketopiperazine alkaloids (17) were isolated from the Vietnamese sediment-derived fungus Aspergillus niveoglaucus. Using chiral HPLC, the enantiomers of cryptoechinuline B (1) were isolated as individual compounds for the first time. (+)-Cryptoechinuline B ( [...] Read more.
Seven known echinulin-related indolediketopiperazine alkaloids (17) were isolated from the Vietnamese sediment-derived fungus Aspergillus niveoglaucus. Using chiral HPLC, the enantiomers of cryptoechinuline B (1) were isolated as individual compounds for the first time. (+)-Cryptoechinuline B (1a) exhibited neuroprotective activity in 6-OHDA-, paraquat-, and rotenone-induced in vitro models of Parkinson’s disease. (−)-Cryptoechinuline B (1b) and neoechinulin C (5) protected the neuronal cells against paraquat-induced damage in a Parkinson’s disease model. Neoechinulin B (4) exhibited cytoprotective activity in a rotenone-induced model, and neoechinulin (7) showed activity in the 6-OHDA-induced model. Full article
Show Figures

Figure 1

Open AccessArticle
Questiomycins, Algicidal Compounds Produced by the Marine Bacterium Alteromonas sp. D and Their Production Cue
Molecules 2019, 24(24), 4522; https://doi.org/10.3390/molecules24244522 - 10 Dec 2019
Abstract
Questiomycin A (1) along with three new compounds, questiomycins C–E (24), were isolated from culture of Alteromonas sp. D, an algicidal marine bacterium, guided by algal lethality assay using the raphidophyte, Chattonella antiqua, one of the [...] Read more.
Questiomycin A (1) along with three new compounds, questiomycins C–E (24), were isolated from culture of Alteromonas sp. D, an algicidal marine bacterium, guided by algal lethality assay using the raphidophyte, Chattonella antiqua, one of the causative organisms of harmful algal bloom. The structures of 14 were assigned on the basis of their spectrometric and spectroscopic data. Compounds 1 to 4 exhibited algicidal activity against C. antiqua with LC50 values ranging from 0.18 to 6.37 M. Co-cultivation experiment revealed that 1 was produced only when the microalgae and the bacterium are in close contact, suggesting that some interactions between them trigger the biosynthesis of questiomycins. These results suggested that the algicidal bacteria such as Alteromonas sp. D can control microalgae chemically in marine ecosystem. Full article
Show Figures

Graphical abstract

Back to TopTop