Next Issue
Previous Issue

E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Table of Contents

Mar. Drugs, Volume 11, Issue 1 (January 2013), Pages 1-273

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
View options order results:
result details:
Displaying articles 1-19
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle Diversity of Peptides Produced by Nodularia spumigena from Various Geographical Regions
Mar. Drugs 2013, 11(1), 1-19; doi:10.3390/md11010001
Received: 12 October 2012 / Revised: 13 November 2012 / Accepted: 11 December 2012 / Published: 21 December 2012
Cited by 13 | PDF Full-text (1020 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Cyanobacteria produce a great variety of non-ribosomal peptides. Among these compounds, both acute toxins and potential drug candidates have been reported. The profile of the peptides, as a stable and specific feature of an individual strain, can be used to discriminate cyanobacteria [...] Read more.
Cyanobacteria produce a great variety of non-ribosomal peptides. Among these compounds, both acute toxins and potential drug candidates have been reported. The profile of the peptides, as a stable and specific feature of an individual strain, can be used to discriminate cyanobacteria at sub-population levels. In our work, liquid chromatography-tandem mass spectrometry was used to elucidate the structures of non-ribosomal peptides produced by Nodularia spumigena from the Baltic Sea, the coastal waters of southern Australia and Lake Iznik in Turkey. In addition to known structures, 9 new congeners of spumigins, 4 aeruginosins and 12 anabaenopeptins (nodulapeptins) were identified. The production of aeruginosins by N. spumigena was revealed in this work for the first time. The isolates from the Baltic Sea appeared to be the richest source of the peptides; they also showed a higher diversity in peptide profiles. The Australian strains were characterized by similar peptide patterns, but distinct from those represented by the Baltic and Lake Iznik isolates. The results obtained with the application of the peptidomic approach were consistent with the published data on the genetic diversity of the Baltic and Australian populations. Full article
(This article belongs to the Special Issue Marine Algae)
Figures

Open AccessArticle Nutritional and Chemical Composition and Antiviral Activity of Cultivated Seaweed Sargassum naozhouense Tseng et Lu
Mar. Drugs 2013, 11(1), 20-32; doi:10.3390/md11010020
Received: 29 October 2012 / Revised: 29 November 2012 / Accepted: 5 December 2012 / Published: 27 December 2012
Cited by 7 | PDF Full-text (425 KB) | HTML Full-text | XML Full-text
Abstract
Sargassum naozhouense is a brown seaweed used in folk medicine and applied for thousands of years in Zhanjiang, Guangdong province, China. This study is the first time to investigate its chemical composition and antiviral activity. On the dry weight basis, this seaweed [...] Read more.
Sargassum naozhouense is a brown seaweed used in folk medicine and applied for thousands of years in Zhanjiang, Guangdong province, China. This study is the first time to investigate its chemical composition and antiviral activity. On the dry weight basis, this seaweed was constituted of ca. 35.18% ash, 11.20% protein, 1.06% lipid and 47.73% total carbohydrate, and the main carbohydrate was water-soluble polysaccharide. The protein analysis indicated the presence of essential amino acids, which accounted for 36.35% of the protein. The most abundant fatty acids were C14:0, C16:0, C18:1 and C20:4. The ash fraction analysis indicated that essential minerals and trace elements, such as Fe, Zn and Cu, were present in the seaweed. IR analysis revealed that polysaccharides from cultivated S. naozhouense may be alginates and fucoidan. The polysaccharides possessed strong antiviral activity against HSV-1 in vitro with EC50 of 8.92 μg/mL. These results demonstrated cultivated S. naozhouense has a potential for its use in functional foods and antiviral new drugs. Full article
(This article belongs to the Special Issue Marine Algae)
Open AccessCommunication Isolation, Characterization, and Bioactivity Evaluation of 3-((6-Methylpyrazin-2-yl)methyl)-1H-indole, a New Alkaloid from a Deep-Sea-Derived Actinomycete Serinicoccus profundi sp. nov.
Mar. Drugs 2013, 11(1), 33-39; doi:10.3390/md11010033
Received: 15 October 2012 / Revised: 7 November 2012 / Accepted: 22 November 2012 / Published: 27 December 2012
Cited by 13 | PDF Full-text (325 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
One new alkaloid, 3-((6-methylpyrazin-2-yl)methyl)-1H-indole (1) was obtained from the deep-sea actinomycete Serinicoccus profundi sp. nov., along with five known compounds (26). Their structures were determined on the basis of detailed analysis of the 1D [...] Read more.
One new alkaloid, 3-((6-methylpyrazin-2-yl)methyl)-1H-indole (1) was obtained from the deep-sea actinomycete Serinicoccus profundi sp. nov., along with five known compounds (26). Their structures were determined on the basis of detailed analysis of the 1D and 2D NMR as well as MS data. The new indole alkaloid displayed weak antimicrobial activity against Staphylococcus aureus ATCC 25923 with an MIC value of 96 μg/mL. It showed no cytotoxicity on a normal human liver cell line (BEL7402) and a human liver tumor cell line (HL-7702). Full article
(This article belongs to the Special Issue Deep-Sea Natural Products)
Open AccessArticle Assessing the Effectiveness of Functional Genetic Screens for the Identification of Bioactive Metabolites
Mar. Drugs 2013, 11(1), 40-49; doi:10.3390/md11010040
Received: 18 October 2012 / Revised: 13 November 2012 / Accepted: 12 December 2012 / Published: 27 December 2012
Cited by 6 | PDF Full-text (473 KB) | HTML Full-text | XML Full-text
Abstract
A common limitation for the identification of novel activities from functional (meta) genomic screens is the low number of active clones detected relative to the number of clones screened. Here we demonstrate that constructing libraries with strains known to produce bioactives can [...] Read more.
A common limitation for the identification of novel activities from functional (meta) genomic screens is the low number of active clones detected relative to the number of clones screened. Here we demonstrate that constructing libraries with strains known to produce bioactives can greatly enhance the screening efficiency, by increasing the “hit-rate” and unmasking multiple activities from the same bacterial source. Full article
(This article belongs to the Special Issue Marine Antibiotics)
Open AccessArticle Fucoxanthin Enhances Cisplatin-Induced Cytotoxicity via NFκB-Mediated Pathway and Downregulates DNA Repair Gene Expression in Human Hepatoma HepG2 Cells
Mar. Drugs 2013, 11(1), 50-66; doi:10.3390/md11010050
Received: 10 October 2012 / Revised: 14 November 2012 / Accepted: 13 December 2012 / Published: 8 January 2013
Cited by 14 | PDF Full-text (1234 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Cisplain, a platinum-containing anticancer drug, has been shown to enhance DNA repair and to inhibit cell apoptosis, leading to drug resistance. Thus, the combination of anticancer drugs with nutritional factors is a potential strategy for improving the efficacy of cisplatin chemotherapy. In [...] Read more.
Cisplain, a platinum-containing anticancer drug, has been shown to enhance DNA repair and to inhibit cell apoptosis, leading to drug resistance. Thus, the combination of anticancer drugs with nutritional factors is a potential strategy for improving the efficacy of cisplatin chemotherapy. In this study, we investigated the anti-proliferative effects of a combination of fucoxanthin, the major non-provitamin A carotenoid found in Undaria Pinnatifida, and cisplatin in human hepatoma HepG2 cells. We found that fucoxanthin (1–10 μΜ) pretreatment for 24 h followed by cisplatin (10 μΜ) for 24 h significantly decreased cell proliferation, as compared with cisplatin treatment alone. Mechanistically, we showed that fucoxanthin attenuated cisplatin-induced NFκB expression and enhanced the NFκB-regulated Bax/Bcl-2 mRNA ratio. Cisplatin alone induced mRNA expression of excision repair cross complementation 1 (ERCC1) and thymidine phosphorylase (TP) through phosphorylation of ERK, p38 and PI3K/AKT pathways. However, fucoxanthin pretreatment significantly attenuated cisplatin-induced ERCC1 and TP mRNA expression, leading to improvement of chemotherapeutic efficacy of cisplatin. The results suggest that a combined treatment with fucoxanthin and cisplatin could lead to a potentially important new therapeutic strategy against human hepatoma cells. Full article
Open AccessArticle Lipid Peroxidation Is another Potential Mechanism besides Pore-Formation Underlying Hemolysis of Tentacle Extract from the Jellyfish Cyanea capillata
Mar. Drugs 2013, 11(1), 67-80; doi:10.3390/md11010067
Received: 22 September 2012 / Revised: 2 November 2012 / Accepted: 12 December 2012 / Published: 9 January 2013
Cited by 11 | PDF Full-text (644 KB) | HTML Full-text | XML Full-text
Abstract
This study was performed to explore other potential mechanisms underlying hemolysis in addition to pore-formation of tentacle extract (TE) from the jellyfish Cyanea capillata. A dose-dependent increase of hemolysis was observed in rat erythrocyte suspensions and the hemolytic activity of TE [...] Read more.
This study was performed to explore other potential mechanisms underlying hemolysis in addition to pore-formation of tentacle extract (TE) from the jellyfish Cyanea capillata. A dose-dependent increase of hemolysis was observed in rat erythrocyte suspensions and the hemolytic activity of TE was enhanced in the presence of Ca2+, which was attenuated by Ca2+ channel blockers (Diltiazem, Verapamil and Nifedipine). Direct intracellular Ca2+ increase was observed after TE treatment by confocal laser scanning microscopy, and the Ca2+ increase could be depressed by Diltiazem. The osmotic protectant polyethylenglycol (PEG) significantly blocked hemolysis with a molecular mass exceeding 4000 Da. These results support a pore-forming mechanism of TE in the erythrocyte membrane, which is consistent with previous studies by us and other groups. The concentration of malondialdehyde (MDA), an important marker of lipid peroxidation, increased dose-dependently in rat erythrocytes after TE treatment, while in vitro hemolysis of TE was inhibited by the antioxidants ascorbic acid—Vitamin C (Vc)—and reduced glutathione (GSH). Furthermore, in vivo hemolysis and electrolyte change after TE administration could be partly recovered by Vc. These results indicate that lipid peroxidation is another potential mechanism besides pore-formation underlying the hemolysis of TE, and both Ca2+ channel blockers and antioxidants could be useful candidates against the hemolytic activity of jellyfish venoms. Full article
(This article belongs to the collection Bioactive Compounds from Marine Plankton)
Figures

Open AccessArticle Fucoidan Extract Enhances the Anti-Cancer Activity of Chemotherapeutic Agents in MDA-MB-231 and MCF-7 Breast Cancer Cells
Mar. Drugs 2013, 11(1), 81-98; doi:10.3390/md11010081
Received: 12 November 2012 / Revised: 13 December 2012 / Accepted: 14 December 2012 / Published: 9 January 2013
Cited by 19 | PDF Full-text (1420 KB) | HTML Full-text | XML Full-text
Abstract
Fucoidan, a fucose-rich polysaccharide isolated from brown alga, is currently under investigation as a new anti-cancer compound. In the present study, fucoidan extract (FE) from Cladosiphon navae-caledoniae Kylin was prepared by enzymatic digestion. We investigated whether a combination of FE with cisplatin, [...] Read more.
Fucoidan, a fucose-rich polysaccharide isolated from brown alga, is currently under investigation as a new anti-cancer compound. In the present study, fucoidan extract (FE) from Cladosiphon navae-caledoniae Kylin was prepared by enzymatic digestion. We investigated whether a combination of FE with cisplatin, tamoxifen or paclitaxel had the potential to improve the therapeutic efficacy of cancer treatment. These co-treatments significantly induced cell growth inhibition, apoptosis, as well as cell cycle modifications in MDA-MB-231 and MCF-7 cells. FE enhanced apoptosis in cancer cells that responded to treatment with three chemotherapeutic drugs with downregulation of the anti-apoptotic proteins Bcl-xL and Mcl-1. The combination treatments led to an obvious decrease in the phosphorylation of ERK and Akt in MDA-MB-231 cells, but increased the phosphorylation of ERK in MCF-7 cells. In addition, we observed that combination treatments enhanced intracellular ROS levels and reduced glutathione (GSH) levels in breast cancer cells, suggesting that induction of oxidative stress was an important event in the cell death induced by the combination treatments. Full article
Open AccessArticle Soft Coral-Derived Lemnalol Alleviates Monosodium Urate-Induced Gouty Arthritis in Rats by Inhibiting Leukocyte Infiltration and iNOS, COX-2 and c-Fos Protein Expression
Mar. Drugs 2013, 11(1), 99-113; doi:10.3390/md11010099
Received: 28 November 2012 / Revised: 21 December 2012 / Accepted: 26 December 2012 / Published: 10 January 2013
Cited by 8 | PDF Full-text (978 KB) | HTML Full-text | XML Full-text
Abstract
An acute gout attack manifests in the joint as dramatic inflammation. To date, the clinical use of medicinal agents has typically led to undesirable side effects. Numerous efforts have failed to create an effective and safe agent for the treatment of gout. [...] Read more.
An acute gout attack manifests in the joint as dramatic inflammation. To date, the clinical use of medicinal agents has typically led to undesirable side effects. Numerous efforts have failed to create an effective and safe agent for the treatment of gout. Lemnalol — an extract from Formosan soft coral — has documented anti-inflammatory and anti-nociceptive properties. In the present study, we attempt to examine the therapeutic effects of lemnalol on intra-articular monosodium urate (MSU)-induced gouty arthritis in rats. In the present study, we found that treatment with lemnalol (intramuscular [im]), but not colchicine (oral [po]), significantly attenuated MUS-induced mechanical allodynia, paw edema and knee swelling. Histomorphometric and immunohistochemistry analysis revealed that MSU-induced inflammatory cell infiltration, as well as the elevated expression of c-Fos and pro-inflammatory proteins (inducible nitric oxide synthase and cyclooxygenase-2) observed in synovial tissue, were significantly inhibited by treatment with lemnalol. We conclude that lemnalol may be a promising candidate for the development of a new treatment for gout and other acute neutrophil-driven inflammatory diseases. Full article
(This article belongs to the Special Issue Marine Compounds and Inflammation)
Open AccessArticle A New Spatane Diterpenoid from the Cultured Soft Coral Sinularia leptoclados
Mar. Drugs 2013, 11(1), 114-123; doi:10.3390/md11010114
Received: 27 November 2012 / Revised: 11 December 2012 / Accepted: 24 December 2012 / Published: 10 January 2013
Cited by 6 | PDF Full-text (611 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
A new spatane diterpenoid, leptoclalin A (1), along with two previously reported known norcembranoid diterpenes (2 and 3), were isolated from a cultured soft coral Sinularia leptoclados. The structures were determined by extensive spectroscopic analyses and by [...] Read more.
A new spatane diterpenoid, leptoclalin A (1), along with two previously reported known norcembranoid diterpenes (2 and 3), were isolated from a cultured soft coral Sinularia leptoclados. The structures were determined by extensive spectroscopic analyses and by comparison with the spectral data of related known compounds. Metabolite 1 is rarely found in spatane skeletons reported from soft corals. In addition, compound 1 exhibited weak cytotoxicity towards human tumor cell lines T-47 D and K-562. Full article
Figures

Open AccessArticle Antibacterial Polyketides from the Marine Alga-Derived Endophitic Streptomyces sundarbansensis: A Study on Hydroxypyrone Tautomerism
Mar. Drugs 2013, 11(1), 124-135; doi:10.3390/md11010124
Received: 14 November 2012 / Revised: 4 December 2012 / Accepted: 25 December 2012 / Published: 10 January 2013
Cited by 7 | PDF Full-text (667 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Polyketide 13 [=2-hydroxy-5-((6-hydroxy-4-oxo-4H-pyran-2-yl)methyl)-2- propylchroman-4-one] and three related known compounds 7, 9 and 11 were obtained and structurally characterized from Streptomyces sundarbansensis strain, an endophytic actinomycete isolated from the Algerian marine brown algae Fucus sp. Compound 13 was obtained as [...] Read more.
Polyketide 13 [=2-hydroxy-5-((6-hydroxy-4-oxo-4H-pyran-2-yl)methyl)-2- propylchroman-4-one] and three related known compounds 7, 9 and 11 were obtained and structurally characterized from Streptomyces sundarbansensis strain, an endophytic actinomycete isolated from the Algerian marine brown algae Fucus sp. Compound 13 was obtained as the major metabolite from optimized culture conditions, by using Agar state fermentation. Due to tautomeric equilibrium, 13 in CD3OD solution was able to incorporate five deuterium atoms, as deduced by NMR and ESI-MS/MS analysis. The 2-hydroxy-γ-pyrone form was established for these metabolites based on the comparison of their experimental IR spectra with the DFT calculated ones, for both the corresponding 4-hydroxy-α-pyrone and 2-hydroxy-γ-pyrone forms. During antibacterial evaluation, compound 13 stood out as the most active of the series, showing a selective activity against the gram positive pathogenic methicillin-resistant S. aureus (MRSA, MIC = 6 μΜ), with a bacteriostatic effect. Full article
(This article belongs to the Special Issue Marine Antibiotics)
Figures

Open AccessArticle Steroidal Carboxylic Acids from Soft Coral Paraminabea acronocephala
Mar. Drugs 2013, 11(1), 136-145; doi:10.3390/md11010136
Received: 28 November 2012 / Revised: 28 December 2012 / Accepted: 31 December 2012 / Published: 11 January 2013
Cited by 6 | PDF Full-text (546 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Three new steroidal carboxylic acids, paraminabic acids A–C (13) were isolated from a Formosan soft coral Paraminabea acronocephala. The structures of these compounds were established by extensive spectroscopic analysis and chemical methods. Application of the PGME method [...] Read more.
Three new steroidal carboxylic acids, paraminabic acids A–C (13) were isolated from a Formosan soft coral Paraminabea acronocephala. The structures of these compounds were established by extensive spectroscopic analysis and chemical methods. Application of the PGME method allowed the establishment of the absolute configurations at C-25 and C-24 for 1 and 2, respectively. Compound 3 showed potent cytotoxicity toward Hep3B, MDA-MB-231, MCF-7, and A-549 cancer cell lines, with IC50 values ranging from 2.05 to 2.83 μg/mL. Compounds 2 and 3 were found to inhibit the accumulation of the pro-inflammatory iNOS protein. Full article
Figures

Open AccessArticle Isolation and Structural Determination of Two Novel Phlorotannins from the Brown Alga Ecklonia kurome Okamura, and Their Radical Scavenging Activities
Mar. Drugs 2013, 11(1), 165-183; doi:10.3390/md11010165
Received: 12 November 2012 / Revised: 11 December 2012 / Accepted: 4 January 2013 / Published: 18 January 2013
Cited by 9 | PDF Full-text (1155 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Two novel phlorotannins with a molecular weight of 974, temporarily named 974-A and 974-B, were isolated from the polyphenol powder prepared from the edible marine brown alga Ecklonia kurome Okamura, and their chemical structures were determined by spectroscopic method. The [...] Read more.
Two novel phlorotannins with a molecular weight of 974, temporarily named 974-A and 974-B, were isolated from the polyphenol powder prepared from the edible marine brown alga Ecklonia kurome Okamura, and their chemical structures were determined by spectroscopic method. The isolated yield of the total of 974-A and 974-B was approximately 4% (w/w) from the polyphenol powder. In 974-A, the carbon at the C2′ position in the A ring of phlorofucofuroeckol-A forms a C–C bond with the carbon at the C2″ position of the C ring of triphloretol-B, while in 974-B, phlorofucofuroeckol-B and triphloretol-B form a C–C bond in the same manner as in 974-A. These structures were supported by high resolution-MS/MS data. To evaluate the antioxidant activities, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and intracellular radical scavenging assay, using 2′,7′-dichlorofluorescin diacetate (DCFH-DA), were performed for 974-A, 974-B, and four known phlorotannins. The results of the DPPH assay showed that the IC50 values of 974-A, 974-B, phlorofucofuroeckol-A, and dieckol were significantly smaller than those of phlorofucofuroeckol-B, phloroglucinol, α-tocopherol, and ascorbic acid. Furthermore, the DCFH-DA assay suggested that 974-A, 974-B, and dieckol reduce intracellular reactive oxygen species most strongly among the tested compounds. Full article
(This article belongs to the Special Issue Marine Algae)
Figures

Open AccessArticle The Lipid A from the Haloalkaliphilic Bacterium Salinivibrio sharmensis Strain BAGT
Mar. Drugs 2013, 11(1), 184-193; doi:10.3390/md11010184
Received: 11 December 2012 / Revised: 9 January 2013 / Accepted: 11 January 2013 / Published: 21 January 2013
Cited by 1 | PDF Full-text (605 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Lipid A is a major constituent of the lipopolysaccharides (or endotoxins), which are complex amphiphilic macromolecules anchored in the outer membrane of Gram-negative bacteria. The glycolipid lipid A is known to possess the minimal chemical structure for LPSs endotoxic activity, able to [...] Read more.
Lipid A is a major constituent of the lipopolysaccharides (or endotoxins), which are complex amphiphilic macromolecules anchored in the outer membrane of Gram-negative bacteria. The glycolipid lipid A is known to possess the minimal chemical structure for LPSs endotoxic activity, able to cause septic shock. Lipid A isolated from extremophiles is interesting, since very few cases of pathogenic bacteria have been found among these microorganisms. In some cases their lipid A has shown to have an antagonist activity, i.e., it is able to interact with the immune system of the host without triggering a proinflammatory response by blocking binding of substances that could elicit such a response. However, the relationship between the structure and the activity of these molecules is far from being completely clear. A deeper knowledge of the lipid A chemical structure can help the understanding of these mechanisms. In this manuscript, we present our work on the complete structural characterization of the lipid A obtained from the lipopolysaccharides (LPS) of the haloalkaliphilic bacterium Salinivibrio sharmensis. Lipid A was obtained from the purified LPS by mild acid hydrolysis. The lipid A, which contains different number of fatty acids residues, and its partially deacylated derivatives were completely characterized by means of electrospray ionization Fourier transform ion cyclotron (ESI FT-ICR) mass spectrometry and chemical analysis. Full article
(This article belongs to the Special Issue Marine Lipopolysaccharides)
Open AccessArticle The Effect of Sulfated (1→3)-α-l-Fucan from the Brown Alga Saccharina cichorioides Miyabe on Resveratrol-Induced Apoptosis in Colon Carcinoma Cells
Mar. Drugs 2013, 11(1), 194-212; doi:10.3390/md11010194
Received: 1 December 2012 / Revised: 6 January 2013 / Accepted: 14 January 2013 / Published: 21 January 2013
Cited by 11 | PDF Full-text (798 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Accumulating data clearly indicate that the induction of apoptosis by nontoxic natural compounds is a potent defense against the development and progression of many malignancies, including colon cancer. Resveratrol and the fucoidans have been shown to possess potent anti-tumor activity in vitro [...] Read more.
Accumulating data clearly indicate that the induction of apoptosis by nontoxic natural compounds is a potent defense against the development and progression of many malignancies, including colon cancer. Resveratrol and the fucoidans have been shown to possess potent anti-tumor activity in vitro and in vivo. The aim of the present study was to examine whether the combination of a fucoidan from the brown alga Saccharina cichorioides Miyabe and resveratrol would be an effective preventive and/or therapeutic strategy against colon cancer. Based on NMR spectroscopy and MALDI-TOF analysis, the fucoidan isolated and purified from Saccharina cichorioides Miyabe was (1→3)-α-l-fucan with sulfate groups at C2 and C4 of the α-l-fucopyranose residues. The fucoidan enhanced the antiproliferative activity of resveratrol at nontoxic doses and facilitated resveratrol-induced apoptosis in the HCT 116 human colon cancer cell line. Apoptosis was realized by the activation of initiator caspase-9 and effector caspase-7 and -3, followed by the cleavage of PARP. Furthermore, significant inhibition of HCT 116 colony formation was associated with the sensitization of cells to resveratrol by the fucoidan. Taken together, these results demonstrate that the combination of the algal fucoidan with resveratrol may provide a potential therapy against human colon cancer. Full article
Open AccessArticle Comparative Proteomic Analysis Reveals Proteins Putatively Involved in Toxin Biosynthesis in the Marine Dinoflagellate Alexandrium catenella
Mar. Drugs 2013, 11(1), 213-232; doi:10.3390/md11010213
Received: 7 November 2012 / Revised: 27 December 2012 / Accepted: 21 January 2013 / Published: 22 January 2013
Cited by 11 | PDF Full-text (1123 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Alexandrium is a neurotoxin-producing dinoflagellate genus resulting in paralytic shellfish poisonings around the world. However, little is known about the toxin biosynthesis mechanism in Alexandrium. This study compared protein profiles of A. catenella collected at different toxin biosynthesis stages (non-toxin synthesis, [...] Read more.
Alexandrium is a neurotoxin-producing dinoflagellate genus resulting in paralytic shellfish poisonings around the world. However, little is known about the toxin biosynthesis mechanism in Alexandrium. This study compared protein profiles of A. catenella collected at different toxin biosynthesis stages (non-toxin synthesis, initial toxin synthesis and toxin synthesizing) coupled with the cell cycle, and identified differentially expressed proteins using 2-DE and MALDI-TOF-TOF mass spectrometry. The results showed that toxin biosynthesis of A. catenella occurred within a defined time frame in the G1 phase of the cell cycle. Proteomic analysis indicated that 102 protein spots altered significantly in abundance (P < 0.05), and 53 proteins were identified using database searching. These proteins were involved in a variety of biological processes, i.e., protein modification and biosynthesis, metabolism, cell division, oxidative stress, transport, signal transduction, and translation. Among them, nine proteins with known functions in paralytic shellfish toxin-producing cyanobacteria, i.e., methionine S-adenosyltransferase, chloroplast ferredoxin-NADP+ reductase, S-adenosylhomocysteinase, adenosylhomocysteinase, ornithine carbamoyltransferase, inorganic pyrophosphatase, sulfotransferase (similar to), alcohol dehydrogenase and arginine deiminase, varied significantly at different toxin biosynthesis stages and formed an interaction network, indicating that they might be involved in toxin biosynthesis in A. catenella. This study is the first step in the dissection of the behavior of the A. catenella proteome during different toxin biosynthesis stages and provides new insights into toxin biosynthesis in dinoflagellates. Full article
(This article belongs to the Special Issue Marine Algae)
Figures

Open AccessArticle Quorum Sensing Inhibition by Asparagopsis taxiformis, a Marine Macro Alga: Separation of the Compound that Interrupts Bacterial Communication
Mar. Drugs 2013, 11(1), 253-265; doi:10.3390/md11010253
Received: 29 November 2012 / Revised: 26 December 2012 / Accepted: 4 January 2013 / Published: 23 January 2013
Cited by 17 | PDF Full-text (679 KB) | HTML Full-text | XML Full-text
Abstract
The majority of the marine algal species, though completing their life cycle in seawater, are rarely susceptible to fouling, making them an important source of quorum sensing (QS) inhibitory substances. The separation and characterization of QS inhibitors are crucial for any potential [...] Read more.
The majority of the marine algal species, though completing their life cycle in seawater, are rarely susceptible to fouling, making them an important source of quorum sensing (QS) inhibitory substances. The separation and characterization of QS inhibitors are crucial for any potential application. Thirty marine macroalgae were tested for QS inhibition activity by using Chromobacterium violaceum CV026 as the reporter strain, and among them, Asparagopsis taxiformis showed antibacterial, as well as antiquorum, sensing activities. Cinnamaldehyde (75 mM) and methanol were used as positive and negative controls, respectively. The antiquorum sensing activity of A. taxiformis was further confirmed using the sensor strain, Serratia liquefaciens MG44, having green fluorescent protein (gfp). Methanolic extract of the alga was fractionated by solid phase extraction (SPE), and each fraction was tested for QS inhibition. Two types of activities were observed—zone of clearance (antibacterial activity) and zone of inhibition with or without finger-like projections (QS inhibition). Out of five SPE cartridges, Bond Elut PH showed clear separation of these two fractions. The Ion Cyclotron Resonance Fourier Transformation Mass Spectrometer (ICR-FT/MS) analysis of the fractions further supported the bioassay results. The presence of strong QS inhibitory compound in A. taxiformis indicates its potential use in antifouling preparations. Full article
(This article belongs to the Special Issue Marine Algae)
Figures

Open AccessArticle Isolation and Purification of a Peptide from Bullacta exarata and Its Impaction of Apoptosis on Prostate Cancer Cell
Mar. Drugs 2013, 11(1), 266-273; doi:10.3390/md11010266
Received: 6 November 2012 / Revised: 20 December 2012 / Accepted: 24 December 2012 / Published: 23 January 2013
Cited by 8 | PDF Full-text (705 KB) | HTML Full-text | XML Full-text
Abstract
Bullacta exarata was hydrolyzed with trypsin to prepare peptides; Hydrolysates were isolated by ultrafiltration and purified using G-25 gel filtration. The purity of the Bullacta exarata was demonstrated by HPLC and its peptide sequence analysis was detected. The effects of BEPT II [...] Read more.
Bullacta exarata was hydrolyzed with trypsin to prepare peptides; Hydrolysates were isolated by ultrafiltration and purified using G-25 gel filtration. The purity of the Bullacta exarata was demonstrated by HPLC and its peptide sequence analysis was detected. The effects of BEPT II and BEPT II-1 on the proliferation of PC-3 cells were examined using a MTT assay. BEPT II and BEPT II-1 significantly inhibited the proliferation of PC-3 cells in a time- and dose-dependent manner. Annexin V/PI double staining studies showed exposing PC-3 cells to 5, or 15 mg/mL BEPT II-1 for 24 h increased the percentage of the early stage of apoptotic cells from 11.22% to 22.09%. In addition, typical morphologic changes were observed in the cells with acridine orange/ethidium bromide staining. These data support that BEPT II-1 has anticancer properties and merits further investigation to understand the mechanisms of BEPT II-1-induced apoptosis in PC-3 cells. Full article

Review

Jump to: Research

Open AccessReview Beneficial Effects of Marine Algal Compounds in Cosmeceuticals
Mar. Drugs 2013, 11(1), 146-164; doi:10.3390/md11010146
Received: 18 September 2012 / Revised: 19 October 2012 / Accepted: 12 December 2012 / Published: 14 January 2013
Cited by 30 | PDF Full-text (844 KB) | HTML Full-text | XML Full-text
Abstract
The name “cosmeceuticals” is derived from “cosmetics and pharmaceuticals”, indicating that a specific product contains active ingredients. Marine algae have gained much importance in cosmeceutical product development due to their rich bioactive compounds. In the present review, marine algal compounds (phlorotannins, sulfated [...] Read more.
The name “cosmeceuticals” is derived from “cosmetics and pharmaceuticals”, indicating that a specific product contains active ingredients. Marine algae have gained much importance in cosmeceutical product development due to their rich bioactive compounds. In the present review, marine algal compounds (phlorotannins, sulfated polysaccharides and tyrosinase inhibitors) have been discussed toward cosmeceutical application. In addition, atopic dermatitis and the possible role of matrix metalloproteinase (MMP) in skin-related diseases have been explored extensively for cosmeceutical products. The proper development of marine algae compounds will be helpful in cosmeceutical product development and in the development of the cosmeceutical industry. Full article
(This article belongs to the Special Issue Marine Algae)
Figures

Open AccessReview Bioactivity and Applications of Sulphated Polysaccharides from Marine Microalgae
Mar. Drugs 2013, 11(1), 233-252; doi:10.3390/md11010233
Received: 1 November 2012 / Revised: 26 December 2012 / Accepted: 14 January 2013 / Published: 23 January 2013
Cited by 49 | PDF Full-text (484 KB) | HTML Full-text | XML Full-text
Abstract
Marine microalgae have been used for a long time as food for humans, such as Arthrospira (formerly, Spirulina), and for animals in aquaculture. The biomass of these microalgae and the compounds they produce have been shown to possess several biological applications [...] Read more.
Marine microalgae have been used for a long time as food for humans, such as Arthrospira (formerly, Spirulina), and for animals in aquaculture. The biomass of these microalgae and the compounds they produce have been shown to possess several biological applications with numerous health benefits. The present review puts up-to-date the research on the biological activities and applications of polysaccharides, active biocompounds synthesized by marine unicellular algae, which are, most of the times, released into the surrounding medium (exo- or extracellular polysaccharides, EPS). It goes through the most studied activities of sulphated polysaccharides (sPS) or their derivatives, but also highlights lesser known applications as hypolipidaemic or hypoglycaemic, or as biolubricant agents and drag-reducers. Therefore, the great potentials of sPS from marine microalgae to be used as nutraceuticals, therapeutic agents, cosmetics, or in other areas, such as engineering, are approached in this review. Full article
Figures

Journal Contact

MDPI AG
Marine Drugs Editorial Office
St. Alban-Anlage 66, 4052 Basel, Switzerland
marinedrugs@mdpi.com
Tel. +41 61 683 77 34
Fax: +41 61 302 89 18
Editorial Board
Contact Details Submit to Marine Drugs
Back to Top