Marine Drugs

13 pages, 3661 KiB

Open AccessArticle

A Rapid Method for the Determination of Fucoxanthin in Diatom

by Li-Juan Wang, Yong Fan, Ronald L. Parsons, Guang-Rong Hu, Pei-Yu Zhang and Fu-Li Li

Mar. Drugs 2018, 16(1), 33; https://doi.org/10.3390/md16010033 - 22 Jan 2018

Cited by 59 | Viewed by 11992

Fucoxanthin is a natural pigment found in microalgae, especially diatoms and Chrysophyta. Recently, it has been shown to have anti-inflammatory, anti-tumor, and anti-obesityactivity in humans. Phaeodactylum tricornutum is a diatom with high economic potential due to its high content of fucoxanthin and [...] Read more.

Fucoxanthin is a natural pigment found in microalgae, especially diatoms and Chrysophyta. Recently, it has been shown to have anti-inflammatory, anti-tumor, and anti-obesityactivity in humans. Phaeodactylum tricornutum is a diatom with high economic potential due to its high content of fucoxanthin and eicosapentaenoic acid. In order to improve fucoxanthin production, physical and chemical mutagenesis could be applied to generate mutants. An accurate and rapid method to assess the fucoxanthin content is a prerequisite for a high-throughput screen of mutants. In this work, the content of fucoxanthin in P. tricornutum was determined using spectrophotometry instead of high performance liquid chromatography (HPLC). This spectrophotometric method is easier and faster than liquid chromatography and the standard error was less than 5% when compared to the HPLC results. Also, this method can be applied to other diatoms, with standard errors of 3–14.6%. It provides a high throughput screening method for microalgae strains producing fucoxanthin. Full article

(This article belongs to the Special Issue Marine Carotenoids)

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29 pages, 5823 KiB

Open AccessArticle

Twenty-Nine New Limonoids with Skeletal Diversity from the Mangrove Plant, Xylocarpus moluccensis

by Jianzhi Zhang, Wanshan Li, Yiguo Dai, Li Shen and Jun Wu

Mar. Drugs 2018, 16(1), 38; https://doi.org/10.3390/md16010038 - 19 Jan 2018

Cited by 24 | Viewed by 4951

Abstract

Twenty-nine new limonoids—named xylomolins A₁–A₇, B₁–B₂, C₁–C₂, D–F, G₁–G₅, H–I, J₁–J₂, K₁–K₂, L₁–L₂, and M–N, [...] Read more.

Twenty-nine new limonoids—named xylomolins A₁–A₇, B₁–B₂, C₁–C₂, D–F, G₁–G₅, H–I, J₁–J₂, K₁–K₂, L₁–L₂, and M–N, were isolated from the seeds of the mangrove plant, Xylocarpus moluccensis. Compounds 1–13 are mexicanolides with one double bond or two conjugated double bonds, while 14 belongs to a small group of mexicanolides with an oxygen bridge between C1 and C8. Compounds 15–19 are khayanolides containing a Δ^8,14 double bond, whereas 20 and 21 are rare khayanolides containing a Δ^14,15 double bond and Δ^8,9, Δ^14,15 conjugated double bonds, respectively. Compounds 22 and 23 are unusual limonoids possessing a (Z)-bicyclo[5.2.1]dec-3-en-8-one motif, while 24 and 25 are 30-ketophragmalins with Δ^8,9, Δ^14,15 conjugated double bonds. Compounds 26 and 27 are phragmalin 8,9,30-ortho esters, whereas 28 and 29 are azadirone and andirobin derivatives, respectively. The structures of these compounds, including absolute configurations of 15–19, 21–23, and 26, were established by HRESIMS, extensive 1D and 2D NMR investigations, and the comparison of experimental electronic circular dichroism (ECD) spectra. The absolute configuration of 1 was unequivocally established by single-crystal X-ray diffraction analysis, obtained with Cu Kα radiation. The diverse cyclization patterns of 1–29 reveal the strong flexibility of skeletal plasticity in the limonoid biosynthesis of X. moluccensis. Compound 23 exhibited weak antitumor activity against human triple-negative breast MD-MBA-231 cancer cells with an IC₅₀ value of 37.7 μM. Anti-HIV activities of 1, 3, 8, 10, 11, 14, 20, 23–25, and 27 were tested in vitro. However, no compounds showed potent inhibitory activity. Full article

(This article belongs to the Special Issue Bioactive Compounds from Mangroves and Their-Associated Microbes)

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11 pages, 10697 KiB

Open AccessArticle

TTX-Bearing Planocerid Flatworm (Platyhelminthes: Acotylea) in the Ryukyu Islands, Japan

by Hiroyuki Ueda, Shiro Itoi and Haruo Sugita

Mar. Drugs 2018, 16(1), 37; https://doi.org/10.3390/md16010037 - 19 Jan 2018

Cited by 19 | Viewed by 5737

Abstract

Polyclad flatworms comprise a highly diverse and cosmopolitan group of marine turbellarians. Although some species of the genera Planocera and Stylochoplana are known to be tetrodotoxin (TTX)-bearing, there are few new reports. In this study, planocerid-like flatworm specimens were found in the sea [...] Read more.

Polyclad flatworms comprise a highly diverse and cosmopolitan group of marine turbellarians. Although some species of the genera Planocera and Stylochoplana are known to be tetrodotoxin (TTX)-bearing, there are few new reports. In this study, planocerid-like flatworm specimens were found in the sea bottom off the waters around the Ryukyu Islands, Japan. The bodies were translucent with brown reticulate mottle, contained two conical tentacles with eye spots clustered at the base, and had a slightly frilled-body margin. Each specimen was subjected to TTX extraction followed by liquid chromatography with tandem mass spectrometry analysis. Mass chromatograms were found to be identical to those of the TTX standards. The TTX amounts in the two flatworm specimens were calculated to be 468 and 3634 μg. Their external morphology was found to be identical to that of Planocera heda. Phylogenetic analysis based on the sequences of the 28S rRNA gene and cytochrome-c oxidase subunit I gene also showed that both specimens clustered with the flatworms of the genus Planocera (Planocera multitentaculata and Planocera reticulata). This fact suggests that there might be other Planocera species that also possess highly concentrated TTX, contributing to the toxification of TTX-bearing organisms, including fish. Full article

(This article belongs to the Special Issue Tetrodotoxin)

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15 pages, 1816 KiB

Open AccessArticle

Anti-Phytopathogenic and Cytotoxic Activities of Crude Extracts and Secondary Metabolites of Marine-Derived Fungi

by Dong-Lin Zhao, Dan Wang, Xue-Ying Tian, Fei Cao, Yi-Qiang Li and Cheng-Sheng Zhang

Mar. Drugs 2018, 16(1), 36; https://doi.org/10.3390/md16010036 - 18 Jan 2018

Cited by 40 | Viewed by 7216

Abstract

Thirty-one isolates belonging to eight genera in seven orders were identified from 141 strains that were isolated from several marine plants. Alternaria sp. and Fusarium sp. were found to be the predominant fungi. Evaluation of the anti-phytopathogenic bacterial and fungal activities, as well [...] Read more.

Thirty-one isolates belonging to eight genera in seven orders were identified from 141 strains that were isolated from several marine plants. Alternaria sp. and Fusarium sp. were found to be the predominant fungi. Evaluation of the anti-phytopathogenic bacterial and fungal activities, as well as the cytotoxicity of these 31 extracts, revealed that most of them displayed different levels of bioactivities. Due to their interesting bioactivities, two fungal strains—Fusarium equiseti (P18) and Alternaria sp. (P8)—were selected for chemical investigation and compounds 1–4 were obtained. The structure of 1 was elucidated by 1D and 2D NMR analysis, as well as high-resolution electrospray ionization mass spectroscopy (HRESIMS), and the absolute configuration of its stereogenic carbon (C-11) was established by comparison of the experimental and calculated electronic circular-dichroism (ECD) spectra. Moreover, alterperylenol (4) exhibited antibacterial activity against Clavibacter michiganensis with a minimum inhibitory concentration (MIC) of 1.95 μg/mL, which was 2-fold stronger than that of streptomycin sulfate. Additionally, an antibacterial mechanism study revealed that 4 caused membrane hyperpolarization without evidence of destruction of cell membrane integrity. Furthermore, stemphyperylenol (3) displayed potent antifungal activity against Pestallozzia theae and Alternaria brassicicola with MIC values equal to those of carbendazim. The cytotoxicity of 1 and 2 against human lung carcinoma (A-549), human cervical carcinoma (HeLa), and human hepatoma (HepG2) cell lines were also evaluated. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine Microbes - II)

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11 pages, 214 KiB

Open AccessEditorial

Acknowledgement to Reviewers of Marine Drugs in 2017

by Marine Drugs Editorial Office

Mar. Drugs 2018, 16(1), 35; https://doi.org/10.3390/md16010035 - 17 Jan 2018

Viewed by 2834

Abstract

Peer review is an essential part in the publication process, ensuring that Marine Drugs maintains high quality standards for its published papers.[...] Full article

11 pages, 4286 KiB

Open AccessArticle

Microbial Degradation Behavior in Seawater of Polyester Blends Containing Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx)

by Hitoshi Sashiwa, Ryuji Fukuda, Tetsuo Okura, Shunsuke Sato and Atsuyoshi Nakayama

Mar. Drugs 2018, 16(1), 34; https://doi.org/10.3390/md16010034 - 17 Jan 2018

Cited by 71 | Viewed by 7931

Abstract

The microbial degradation behavior of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and its compound with several polyesters such as poly(butylene adipate-co-telephtharate) (PBAT), poly(butylene succinate) (PBS), and polylactic acid (PLA) in seawater was tested by a biological oxygen demand (BOD) method. PHBHHx showed excellent [...] Read more.

The microbial degradation behavior of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and its compound with several polyesters such as poly(butylene adipate-co-telephtharate) (PBAT), poly(butylene succinate) (PBS), and polylactic acid (PLA) in seawater was tested by a biological oxygen demand (BOD) method. PHBHHx showed excellent biodegradation in seawater in this study. In addition, the biodegradation rate of several blends was much influenced by the weight ratio of PHBHHx in their blends and decreased in accordance with the decrement of PHBHHX ratio. The surface morphology of the sheet was important factor for controlling the biodegradation rate of PHBHHx-containing blends in seawater. Full article

(This article belongs to the Special Issue Marine Biodegradable Polymers)

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15 pages, 1475 KiB

Open AccessArticle

Low Molecular Weight Chitosan-Insulin Complexes Solubilized in a Mixture of Self-Assembled Labrosol and Plurol Oleaque and Their Glucose Reduction Activity in Rats

by Amani M. Elsayed, Aseel H. Khaled, Mayyas M. Al Remawi, Nidal A. Qinna, Hussam Abu Farsakh and Adnan A. Badwan

Mar. Drugs 2018, 16(1), 32; https://doi.org/10.3390/md16010032 - 16 Jan 2018

Cited by 11 | Viewed by 4922

Abstract

Oral insulin delivery that better mimics physiological pathways is a necessity as it ensures patient comfort and compliance. A system which is based on a vehicle of nano order where positively charged chitosan interacts with negatively charged insulin and forms a polyelectrolyte complex [...] Read more.

Oral insulin delivery that better mimics physiological pathways is a necessity as it ensures patient comfort and compliance. A system which is based on a vehicle of nano order where positively charged chitosan interacts with negatively charged insulin and forms a polyelectrolyte complex (PEC) solubilizate, which is then solubilized into an oily phase of oleic acid, labrasol, and plurol oleaque-protects insulin against enzymatic gastrointestinal reduction. The use of an anionic fatty acid in the oily phase, such as oleic acid, is thought to allow an interaction with cationic chitosan, hence reducing particle size. Formulations were assessed based on their hypoglycaemic capacities in diabetic rats as compared to conventional subcutaneous dosage forms. 50 IU/kg oral insulin strength could only induce blood glucose reduction equivalent to that of 5 IU/kg (1 International unit = 0.0347 mg of human insulin). Parameters that influence the pharmacological availability were evaluated. A preliminary investigation of the mechanism of absorption suggests the involvement of the lymphatic route. Full article

(This article belongs to the Special Issue Marine Chitin)

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16 pages, 4677 KiB

Open AccessArticle

Specific Molecular Signatures for Type II Crustins in Penaeid Shrimp Uncovered by the Identification of Crustin-Like Antimicrobial Peptides in Litopenaeus vannamei

by Cairé Barreto, Jaqueline Da Rosa Coelho, Jianbo Yuan, Jianhai Xiang, Luciane Maria Perazzolo and Rafael Diego Rosa

Mar. Drugs 2018, 16(1), 31; https://doi.org/10.3390/md16010031 - 16 Jan 2018

Cited by 29 | Viewed by 5714

Abstract

Crustins form a large family of antimicrobial peptides (AMPs) in crustaceans composed of four sub-groups (Types I-IV). Type II crustins (Type IIa or “Crustins” and Type IIb or “Crustin-like”) possess a typical hydrophobic N-terminal region and are by far the most representative sub-group [...] Read more.

Crustins form a large family of antimicrobial peptides (AMPs) in crustaceans composed of four sub-groups (Types I-IV). Type II crustins (Type IIa or “Crustins” and Type IIb or “Crustin-like”) possess a typical hydrophobic N-terminal region and are by far the most representative sub-group found in penaeid shrimp. To gain insight into the molecular diversity of Type II crustins in penaeids, we identified and characterized a Type IIb crustin in Litopenaeus vannamei (Crustin-like Lv) and compared Type II crustins at both molecular and transcriptional levels. Although L. vannamei Type II crustins (Crustin Lv and Crustin-like Lv) are encoded by separate genes, they showed a similar tissue distribution (hemocytes and gills) and transcriptional response to the shrimp pathogens Vibrio harveyi and White spot syndrome virus (WSSV). As Crustin Lv, Crustin-like Lv transcripts were found to be present early in development, suggesting a maternal contribution to shrimp progeny. Altogether, our in silico and transcriptional data allowed to conclude that (1) each sub-type displays a specific amino acid signature at the C-terminal end holding both the cysteine-rich region and the whey acidic protein (WAP) domain, and that (2) shrimp Type II crustins evolved from a common ancestral gene that conserved a similar pattern of transcriptional regulation. Full article

(This article belongs to the Collection Bioactive Compounds from Marine Invertebrates)

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12 pages, 2422 KiB

Open AccessArticle

Characterization of a Novel Alginate Lyase from Marine Bacterium Vibrio furnissii H1

by Xiaoyan Zhu, Xiangqian Li, Hao Shi, Jia Zhou, Zhongbiao Tan, Mengdi Yuan, Peng Yao and Xiaoyan Liu

Mar. Drugs 2018, 16(1), 30; https://doi.org/10.3390/md16010030 - 15 Jan 2018

Cited by 39 | Viewed by 5296

Abstract

Alginate lyases show great potential for industrial and medicinal applications, especially as an attractive biocatalyst for the production of oligosaccharides with special bioactivities. A novel alginate lyase, AlyH1, from the marine bacterium Vibrio furnissii H1, which has been newly isolated from rotten seaweed, [...] Read more.

Alginate lyases show great potential for industrial and medicinal applications, especially as an attractive biocatalyst for the production of oligosaccharides with special bioactivities. A novel alginate lyase, AlyH1, from the marine bacterium Vibrio furnissii H1, which has been newly isolated from rotten seaweed, was purified and characterized. The purified enzyme showed the specific activity of 2.40 U/mg. Its molecular mass was 35.8 kDa. The optimal temperature and pH were 40 °C and pH 7.5, respectively. AlyH1 maintained stability at neutral pH (7.0–8.0) and temperatures below 30 °C. Metal ions Na⁺, Mg²⁺, and K⁺ increased the activity of the enzyme. With sodium alginate as the substrate, the Km and Vmax values of AlyH1 were 2.28 mg/mL and 2.81 U/mg, respectively. AlyH1 exhibited activities towards both polyguluronate and polymannuronate, and preferentially degraded polyguluronate. Products prepared from sodium alginate by AlyH1 were displayed to be di-, tri-, and tetra-alginate oligosaccharides. A partial amino acid sequence (190 aa) of AlyH1 analysis suggested that AlyH1 was an alginate lyase of polysaccharide lyase family 7. The sequence showed less than 77% identity to the reported alginate lyases. These data demonstrated that AlyH1 could be as a novel and potential candidate in application of alginate oligosaccharides production with low polymerization degrees. Full article

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12 pages, 3943 KiB

Open AccessArticle

Optimization of Extraction Conditions and Characterization of Pepsin-Solubilised Collagen from Skin of Giant Croaker (Nibea japonica)

by Fangmiao Yu, Chuhong Zong, Shujie Jin, Jiawen Zheng, Nan Chen, Ju Huang, Yan Chen, Fangfang Huang, Zuisu Yang, Yunping Tang and Guofang Ding

Mar. Drugs 2018, 16(1), 29; https://doi.org/10.3390/md16010029 - 14 Jan 2018

Cited by 64 | Viewed by 6528

Abstract

In the present study, response surface methodology was performed to investigate the effects of extraction parameters on pepsin-solubilised collagen (PSC) from the skin of the giant croaker Nibea japonica. The optimum extraction conditions of PSC were as follows: concentration of pepsin was [...] Read more.

In the present study, response surface methodology was performed to investigate the effects of extraction parameters on pepsin-solubilised collagen (PSC) from the skin of the giant croaker Nibea japonica. The optimum extraction conditions of PSC were as follows: concentration of pepsin was 1389 U/g, solid-liquid ratio was 1:57 and hydrolysis time was 8.67 h. Under these conditions, the extraction yield of PSC was up to 84.85%, which is well agreement with the predict value of 85.03%. The PSC from Nibea japonica skin was then characterized as type I collagen by using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The fourier transforms infrared spetroscopy (FTIR) analysis revealed that PSC maintains its triple-helical structure by the hydrogen bond. All PSCs were soluble in the pH range of 1.0–4.0 and decreases in solubility were observed at neutral or alkaline conditions. All PSCs had a decrease in solubility in the presence of sodium chloride, especially with a concentration above 2%. So, the Nibea japonica skin could serve as another potential source of collagen. Full article

(This article belongs to the Special Issue Collagen from Marine Biological Source and Medical Applications)

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19 pages, 1921 KiB

Open AccessArticle

Evaluation of Rapid, Early Warning Approaches to Track Shellfish Toxins Associated with Dinophysis and Alexandrium Blooms

by Theresa K. Hattenrath-Lehmann, Mark W. Lusty, Ryan B. Wallace, Bennie Haynes, Zhihong Wang, Maggie Broadwater, Jonathan R. Deeds, Steve L. Morton, William Hastback, Leonora Porter, Karen Chytalo and Christopher J. Gobler

Mar. Drugs 2018, 16(1), 28; https://doi.org/10.3390/md16010028 - 13 Jan 2018

Cited by 26 | Viewed by 6043

Abstract

Marine biotoxin-contaminated seafood has caused thousands of poisonings worldwide this century. Given these threats, there is an increasing need for improved technologies that can be easily integrated into coastal monitoring programs. This study evaluates approaches for monitoring toxins associated with recurrent toxin-producing Alexandrium [...] Read more.

Marine biotoxin-contaminated seafood has caused thousands of poisonings worldwide this century. Given these threats, there is an increasing need for improved technologies that can be easily integrated into coastal monitoring programs. This study evaluates approaches for monitoring toxins associated with recurrent toxin-producing Alexandrium and Dinophysis blooms on Long Island, NY, USA, which cause paralytic and diarrhetic shellfish poisoning (PSP and DSP), respectively. Within contrasting locations, the dynamics of pelagic Alexandrium and Dinophysis cell densities, toxins in plankton, and toxins in deployed blue mussels (Mytilus edulis) were compared with passive solid-phase adsorption toxin tracking (SPATT) samplers filled with two types of resin, HP20 and XAD-2. Multiple species of wild shellfish were also collected during Dinophysis blooms and used to compare toxin content using two different extraction techniques (single dispersive and double exhaustive) and two different toxin analysis assays (liquid chromatography/mass spectrometry and the protein phosphatase inhibition assay (PP2A)) for the measurement of DSP toxins. DSP toxins measured in the HP20 resin were significantly correlated (R² = 0.7–0.9, p < 0.001) with total DSP toxins in shellfish, but were detected more than three weeks prior to detection in deployed mussels. Both resins adsorbed measurable levels of PSP toxins, but neither quantitatively tracked Alexandrium cell densities, toxicity in plankton or toxins in shellfish. DSP extraction and toxin analysis methods did not differ significantly (p > 0.05), were highly correlated (R² = 0.98–0.99; p < 0.001) and provided complete recovery of DSP toxins from standard reference materials. Blue mussels (Mytilus edulis) and ribbed mussels (Geukensia demissa) were found to accumulate DSP toxins above federal and international standards (160 ng g⁻¹) during Dinophysis blooms while Eastern oysters (Crassostrea virginica) and soft shell clams (Mya arenaria) did not. This study demonstrated that SPATT samplers using HP20 resin coupled with PP2A technology could be used to provide early warning of DSP, but not PSP, events for shellfish management. Full article

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16 pages, 472 KiB

Open AccessReview

Facial Bone Reconstruction Using both Marine or Non-Marine Bone Substitutes: Evaluation of Current Outcomes in a Systematic Literature Review

by Marco Cicciù, Gabriele Cervino, Alan Scott Herford, Fausto Famà, Ennio Bramanti, Luca Fiorillo, Floriana Lauritano, Sergio Sambataro, Giuseppe Troiano and Luigi Laino

Mar. Drugs 2018, 16(1), 27; https://doi.org/10.3390/md16010027 - 13 Jan 2018

Cited by 70 | Viewed by 5601

Abstract

The aim of the present investigation was to systematically analyse the literature on the facial bone reconstruction defect using marine collagen or not and to evaluate a predictable treatment for their clinical management. The revision has been performed by searched MEDLINE and EMBASE [...] Read more.

The aim of the present investigation was to systematically analyse the literature on the facial bone reconstruction defect using marine collagen or not and to evaluate a predictable treatment for their clinical management. The revision has been performed by searched MEDLINE and EMBASE databases from 2007 to 2017. Clinical trials and animal in vitro studies that had reported the application of bone substitutes or not for bone reconstruction defect and using marine collagen or other bone substitute material were recorded following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The first selection involved 1201 citations. After screening and evaluation of suitability, 39 articles were added at the revision process. Numerous discrepancies among the papers about bone defects morphology, surgical protocols, and selection of biomaterials were found. All selected manuscripts considered the final clinical success after the facial bone reconstruction applying bone substitutes. However, the scientific evidence regarding the vantage of the appliance of a biomaterial versus autologous bone still remains debated. Marine collagen seems to favor the dimensional stability of the graft and it could be an excellent carrier for growth factors. Full article

(This article belongs to the Special Issue Collagen from Marine Biological Source and Medical Applications)

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31 pages, 2165 KiB

Open AccessReview

A Review of the Biological Activities of Microalgal Carotenoids and Their Potential Use in Healthcare and Cosmetic Industries

by Ramaraj Sathasivam and Jang-Seu Ki

Mar. Drugs 2018, 16(1), 26; https://doi.org/10.3390/md16010026 - 12 Jan 2018

Cited by 345 | Viewed by 15810

Abstract

Carotenoids are natural pigments that play pivotal roles in many physiological functions. The characteristics of carotenoids, their effects on health, and the cosmetic benefits of their usage have been under investigation for a long time; however, most reviews on this subject focus on [...] Read more.

Carotenoids are natural pigments that play pivotal roles in many physiological functions. The characteristics of carotenoids, their effects on health, and the cosmetic benefits of their usage have been under investigation for a long time; however, most reviews on this subject focus on carotenoids obtained from several microalgae, vegetables, fruits, and higher plants. Recently, microalgae have received much attention due to their abilities in producing novel bioactive metabolites, including a wide range of different carotenoids that can provide for health and cosmetic benefits. The main objectives of this review are to provide an updated view of recent work on the health and cosmetic benefits associated with carotenoid use, as well as to provide a list of microalgae that produce different types of carotenoids. This review could provide new insights to researchers on the potential role of carotenoids in improving human health. Full article

(This article belongs to the Special Issue Marine Carotenoids)

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13 pages, 2207 KiB

Open AccessArticle

Lipid-Lowering Polyketides from the Fungus Penicillium Steckii HDN13-279

by Guihong Yu, Shuai Wang, Lu Wang, Qian Che, Tianjiao Zhu, Guojian Zhang, Qianqun Gu, Peng Guo and Dehai Li

Mar. Drugs 2018, 16(1), 25; https://doi.org/10.3390/md16010025 - 12 Jan 2018

Cited by 21 | Viewed by 4824

Abstract

Seven new polyketides, named tanzawaic acids R–X (1–6, 11), along with seven known analogues (7–10 and 12–14), were isolated from Penicillium steckii HDN13-279. Their structures, including the absolute configurations, were elucidated by [...] Read more.

Seven new polyketides, named tanzawaic acids R–X (1–6, 11), along with seven known analogues (7–10 and 12–14), were isolated from Penicillium steckii HDN13-279. Their structures, including the absolute configurations, were elucidated by NMR, MS, X-ray diffraction, circular dichroism (CD) analyses and chemical derivatization. Five compounds (2, 3, 6, 10 and 12) significantly decreased the oleic acid (OA)-elicited lipid accumulation in HepG2 liver cells at the concentration of 10 μM, among which, four compounds (3, 6, 10 and 12) significantly decreased intracellular total cholesterol (TC) levels and three Compounds (3, 6, and 10) significantly decreased intracellular triglyceride (TG) levels. Moreover, the TG-lowering capacities of compounds 6 and 10 were comparable with those of simvastatin, with the TG levels being nearly equal to blank control. This is the first report on the lipid-lowering activity of tanzawaic acid derivatives. Full article

(This article belongs to the Collection Marine Drugs in the Management of Metabolic Diseases)

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18 pages, 3919 KiB

Open AccessArticle

Antibacterial and Antioxidant Capacities and Attenuation of Lipid Accumulation in 3T3-L1 Adipocytes by Low-Molecular-Weight Fucoidans Prepared from Compressional-Puffing-Pretreated Sargassum Crassifolium

by Chun-Yung Huang, Chia-Hung Kuo and Chia-Hsin Lee

Mar. Drugs 2018, 16(1), 24; https://doi.org/10.3390/md16010024 - 11 Jan 2018

Cited by 35 | Viewed by 5412

Abstract

In this study, we extracted fucoidan from compressional-puffing-pretreated Sargassum crassifolium by hot water. The crude extract of fucoidan (SC) was degraded by various degradation reagents and four low-molecular-weight (LMW) fucoidans, namely SCO (degradation by hydrogen peroxide), SCA (degradation by ascorbic acid), SCOA (degradation [...] Read more.

In this study, we extracted fucoidan from compressional-puffing-pretreated Sargassum crassifolium by hot water. The crude extract of fucoidan (SC) was degraded by various degradation reagents and four low-molecular-weight (LMW) fucoidans, namely SCO (degradation by hydrogen peroxide), SCA (degradation by ascorbic acid), SCOA (degradation by hydrogen peroxide + ascorbic acid), and SCH (degradation by hydrogen chloride) were obtained. The degradation reagents studied could effectively degrade fucoidan into LMW fucoidans, as revealed by intrinsic viscosity, agarose gel electrophoresis, and molecular weight analyses. These LMW fucoidans had higher uronic acid content and sulfate content than those of SC. It was found that SCOA exhibited antibacterial activity. All LMW fucoidans showed antioxidant activities as revealed by DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt), and FRAP (ferric reducing antioxidant power) methods. Biological experiments showed that SC and SCOA had relatively high activity for the reversal of H₂O₂-induced cell death in 3T3-L1 adipocytes, and SCOA showed the highest effect on attenuation of lipid accumulation in 3T3-L1 adipocytes. Therefore, for the LMW fucoidans tested, SCOA showed antibacterial activity and had a high fucose content, high sulfate content, high activity for the reversal of H₂O₂-induced cell death, and a marked effect on attenuation of lipid accumulation. It can thus be recommended as a natural and safe antibacterial and anti-adipogenic agent for food, cosmetic, and nutraceutical applications. Full article

(This article belongs to the Special Issue Nutraceuticals and Functional Foods)

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21 pages, 4188 KiB

Open AccessArticle

Nanocomposite of Half-Fin Anchovy Hydrolysates/Zinc Oxide Nanoparticles Exhibits Actual Non-Toxicity and Regulates Intestinal Microbiota, Short-Chain Fatty Acids Production and Oxidative Status in Mice

by Ru Song, Jianbin Yao, Qingqing Shi and Rongbian Wei

Mar. Drugs 2018, 16(1), 23; https://doi.org/10.3390/md16010023 - 11 Jan 2018

Cited by 27 | Viewed by 6695

Abstract

The nanocomposite of half-fin anchovy hydrolysates (HAHp) and zinc oxide nanoparticles (ZnO NPs) (named as HAHp(3.0)/ZnO NPs) demonstrated increased antibacterial activity compared to either HAHp(3.0) or ZnO NPs as per our previous studies. Also, reactive oxygen species (ROS) formation was detected in Escherichia [...] Read more.

The nanocomposite of half-fin anchovy hydrolysates (HAHp) and zinc oxide nanoparticles (ZnO NPs) (named as HAHp(3.0)/ZnO NPs) demonstrated increased antibacterial activity compared to either HAHp(3.0) or ZnO NPs as per our previous studies. Also, reactive oxygen species (ROS) formation was detected in Escherichia coli cells after treatment with HAHp(3.0)/ZnO NPs. The aim of the present study was to evaluate the acute toxicity of this nanocomposite and to investigate its effect on intestinal microbiota composition, short-chain fatty acids (SCFAs) production, and oxidative status in healthy mice. The limit test studies show that this nanoparticle is non-toxic at the doses tested. The administration of HAHp(3.0)/ZnO NPs, daily dose of 1.0 g/kg body weight for 14 days, increased the number of goblet cells in jejunum. High-throughput 16S ribosomal RNA gene sequencing of fecal samples revealed that HAHp(3.0)/ZnO NPs increased Firmicutes and reduced Bacteriodetes abundances in female mice. Furthermore, the microbiota for probiotic-type bacteria, including Lactobacillus and Bifidobacterium, and SCFAs-producing bacteria in the Clostridia class, e.g., Lachnospiraceae_unclassified and Lachnospiraceae_UCG-001, were enriched in the feces of female mice. Increases of SCFAs, especially statistically increased propionic and butyric acids, indicated the up-regulated anti-inflammatory activity of HAHp(3.0)/ZnO NPs. Additionally, some positive responses in liver, like markedly increased glutathione and decreased malonaldehyde contents, indicated the improved oxidative status. Therefore, our results suggest that HAHp(3.0)/ZnO NPs could have potential applications as a safe regulator of intestinal microbiota or also can be used as an antioxidant used in food products. Full article

(This article belongs to the Special Issue Pre-Clinical Marine Drug Discovery)

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14 pages, 1280 KiB

Open AccessArticle

Bacillibactin and Bacillomycin Analogues with Cytotoxicities against Human Cancer Cell Lines from Marine Bacillus sp. PKU-MA00093 and PKU-MA00092

by Mengjie Zhou, Fawang Liu, Xiaoyan Yang, Jing Jin, Xin Dong, Ke-Wu Zeng, Dong Liu, Yingtao Zhang, Ming Ma and Donghui Yang

Mar. Drugs 2018, 16(1), 22; https://doi.org/10.3390/md16010022 - 10 Jan 2018

Cited by 32 | Viewed by 7652

Abstract

Nonribosomal peptides from marine Bacillus strains have received considerable attention for their complex structures and potent bioactivities. In this study, we carried out PCR-based genome mining for potential nonribosomal peptides producers from our marine bacterial library. Twenty-one “positive” strains were screened out from [...] Read more.

Nonribosomal peptides from marine Bacillus strains have received considerable attention for their complex structures and potent bioactivities. In this study, we carried out PCR-based genome mining for potential nonribosomal peptides producers from our marine bacterial library. Twenty-one “positive” strains were screened out from 180 marine bacterial strains, and subsequent small-scale fermentation, HPLC and phylogenetic analysis afforded Bacillus sp. PKU-MA00092 and PKU-MA00093 as two candidates for large-scale fermentation and isolation. Ten nonribosomal peptides, including four bacillibactin analogues (1–4) and six bacillomycin D analogues (5–10) were discovered from Bacillus sp. PKU-MA00093 and PKU-MA00092, respectively. Compounds 1 and 2 are two new compounds and the ¹H NMR and ¹³C NMR data of compounds 7 and 9 is first provided. All compounds 1–10 were assayed for their cytotoxicities against human cancer cell lines HepG2 and MCF7, and the bacillomycin D analogues 7–10 showed moderate cytotoxicities with IC₅₀ values from 2.9 ± 0.1 to 8.2 ± 0.2 µM. The discovery of 5–10 with different fatty acid moieties gave us the opportunity to reveal the structure-activity relationships of bacillomycin analogues against these human cancer cell lines. These results enrich the structural diversity and bioactivity properties of nonribosomal peptides from marine Bacillus strains. Full article

(This article belongs to the Special Issue Genome Mining and Marine Microbial Natural Products)

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12 pages, 1930 KiB

Open AccessArticle

Posidonia oceanica (L.) Delile Ethanolic Extract Modulates Cell Activities with Skin Health Applications

by Laura Cornara, Giulia Pastorino, Barbara Borghesi, Annalisa Salis, Marco Clericuzio, Carla Marchetti, Gianluca Damonte and Bruno Burlando

Mar. Drugs 2018, 16(1), 21; https://doi.org/10.3390/md16010021 - 10 Jan 2018

Cited by 21 | Viewed by 5965

Abstract

Seagrasses are high plants sharing adaptive metabolic features with both terrestrial plants and marine algae, resulting in a phytocomplex possibly endowed with interesting biological properties. The aim of this study is to evaluate the in vitro activities on skin cells of an ethanolic [...] Read more.

Seagrasses are high plants sharing adaptive metabolic features with both terrestrial plants and marine algae, resulting in a phytocomplex possibly endowed with interesting biological properties. The aim of this study is to evaluate the in vitro activities on skin cells of an ethanolic extract obtained from the leaves of Posidonia oceanica (L.) Delile, family Potamogetonaceae, herein named Posidonia ethanolic extract (PEE). PEE showed high radical scavenging activity, high phenolic content, and resulted rich in chicoric acid, as determined through HPLC-MS analysis. The use of MTT assay on fibroblasts showed a PEE cytotoxicity threshold (IC₀₅) of 50 µg/mL at 48 h, while a sub-toxic dose of 20 µg/mL induced a significant increase of fibroblast growth rate after 10 days. In addition, an ELISA assay revealed that PEE doses of 5 and 10 µg/mL induced collagen production in fibroblasts. PEE induced dose-dependent mushroom tyrosinase inhibition, up to about 45% inhibition at 1000 µg/mL, while 50% reduction of melanin was observed in melanoma cells exposed to 50 µg/mL PEE. Finally, PEE lipolytic activity was assessed by measuring glycerol release from adipocytes following triglyceride degradation. In conclusion, we have collected new data about the biological activities of the phytocomplex of P. oceanica seagrass on skin cells. Our findings indicate that PEE could be profitably used in the development of products for skin aging, undesired hyperpigmentation, and cellulite. Full article

(This article belongs to the Special Issue Marine Health Compounds: From Extraction to Food and Pharmaceutical Application)

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17 pages, 581 KiB

Open AccessReview

Sponges: A Reservoir of Genes Implicated in Human Cancer

by Helena Ćetković, Mirna Halasz and Maja Herak Bosnar

Mar. Drugs 2018, 16(1), 20; https://doi.org/10.3390/md16010020 - 10 Jan 2018

Cited by 16 | Viewed by 6929

Abstract

Recently, it was shown that the majority of genes linked to human diseases, such as cancer genes, evolved in two major evolutionary transitions—the emergence of unicellular organisms and the transition to multicellularity. Therefore, it has been widely accepted that the majority of disease-related [...] Read more.

Recently, it was shown that the majority of genes linked to human diseases, such as cancer genes, evolved in two major evolutionary transitions—the emergence of unicellular organisms and the transition to multicellularity. Therefore, it has been widely accepted that the majority of disease-related genes has already been present in species distantly related to humans. An original way of studying human diseases relies on analyzing genes and proteins that cause a certain disease using model organisms that belong to the evolutionary level at which these genes have emerged. This kind of approach is supported by the simplicity of the genome/proteome, body plan, and physiology of such model organisms. It has been established for quite some time that sponges are an ideal model system for such studies, having a vast variety of genes known to be engaged in sophisticated processes and signalling pathways associated with higher animals. Sponges are considered to be the simplest multicellular animals and have changed little during evolution. Therefore, they provide an insight into the metazoan ancestor genome/proteome features. This review compiles current knowledge of cancer-related genes/proteins in marine sponges. Full article

(This article belongs to the Collection Marine Compounds and Cancer)

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13 pages, 3590 KiB

Open AccessArticle

The Bioactive Extract of Pinnigorgia sp. Induces Apoptosis of Hepatic Stellate Cells via ROS-ERK/JNK-Caspase-3 Signaling

by Liang-Mou Kuo, Po-Jen Chen, Ping-Jyun Sung, Yu-Chia Chang, Chun-Ting Ho, Yi-Hsiu Wu and Tsong-Long Hwang

Mar. Drugs 2018, 16(1), 19; https://doi.org/10.3390/md16010019 - 9 Jan 2018

Cited by 41 | Viewed by 5700

Abstract

The activation of hepatic stellate cells (HSCs) is a significant phenomenon during the pathogenesis of liver disorders, including liver cirrhosis and fibrosis. Here, we identified that the extract from a gorgonian coral Pinnigorgia sp. (Pin) induced apoptosis of HSC-T6 cells. Pin inhibited the [...] Read more.

The activation of hepatic stellate cells (HSCs) is a significant phenomenon during the pathogenesis of liver disorders, including liver cirrhosis and fibrosis. Here, we identified that the extract from a gorgonian coral Pinnigorgia sp. (Pin) induced apoptosis of HSC-T6 cells. Pin inhibited the viability of HSC-T6 cells and increased their subG1 population, DNA fragmentation, caspase-3 activation, and reactive oxygen species (ROS) production in a concentration-dependent manner. The Pin-induced ROS generation and apoptotic effects were significantly reversed by a thiol antioxidant, N-acetylcysteine (NAC). Additionally, Pin induced ERK/JNK phosphorylation and pharmacological inhibition of ERK/JNK rescued the Pin-induced cell death. Pin-activated ERK/JNK were significantly reduced after the administration of NAC; however, the inhibition of ERK/JNK failed to change the Pin-induced ROS production. Similarly, pinnigorgiol A, a pure compound isolated from Pin, elicited ROS production and apoptosis in HSC-T6 cells. The pinnigorgiol A-induced apoptosis was retrained by NAC. Together, it appears that Pin leads to apoptosis in HSC-T6 cells through ROS-mediated ERK/JNK signaling and caspase-3 activation. Pinnigorgiol A serves as a bioactive compound of Pin and may exhibit therapeutic potential by clearance of HSCs. Full article

(This article belongs to the Special Issue Development and Application of Herbal Medicine from Marine Origin)

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18 pages, 7788 KiB

Open AccessArticle

Isoaaptamine Induces T-47D Cells Apoptosis and Autophagy via Oxidative Stress

by Chih-Fung Wu, Man-Gang Lee, Mohamed El-Shazly, Kuei-Hung Lai, Seng-Chung Ke, Chiang-Wen Su, Shou-Ping Shih, Ping-Jyun Sung, Ming-Chang Hong, Zhi-Hong Wen and Mei-Chin Lu

Mar. Drugs 2018, 16(1), 18; https://doi.org/10.3390/md16010018 - 9 Jan 2018

Cited by 42 | Viewed by 6002

Abstract

Aaptos is a genus of marine sponge which belongs to Suberitidae and is distributed in tropical and subtropical oceans. Bioactivity-guided fractionation of Aaptos sp. methanolic extract resulted in the isolation of aaptamine, demethyloxyaaptamine, and isoaaptamine. The cytotoxic activity of the isolated compounds was [...] Read more.

Aaptos is a genus of marine sponge which belongs to Suberitidae and is distributed in tropical and subtropical oceans. Bioactivity-guided fractionation of Aaptos sp. methanolic extract resulted in the isolation of aaptamine, demethyloxyaaptamine, and isoaaptamine. The cytotoxic activity of the isolated compounds was evaluated revealing that isoaaptamine exhibited potent cytotoxic activity against breast cancer T-47D cells. In a concentration-dependent manner, isoaaptamine inhibited the growth of T-47D cells as indicated by short-(MTT) and long-term (colony formation) anti-proliferative assays. The cytotoxic effect of isoaaptamine was mediated through apoptosis as indicated by DNA ladder formation, caspase-7 activation, XIAP inhibition and PARP cleavage. Transmission electron microscopy and flow cytometric analysis using acridine orange dye indicated that isoaaptamine treatment could induce T-47D cells autophagy. Immunoblot assays demonstrated that isoaaptamine treatment significantly activated autophagy marker proteins such as type II LC-3. In addition, isoaaptamine treatment enhanced the activation of DNA damage (γH2AX) and ER stress-related proteins (IRE1 α and BiP). Moreover, the use of isoaaptamine resulted in a significant increase in the generation of reactive oxygen species (ROS) as well as in the disruption of mitochondrial membrane potential (MMP). The pretreatment of T-47D cells with an ROS scavenger, N-acetyl-l-cysteine (NAC), attenuated the apoptosis and MMP disruption induced by isoaaptamine up to 90%, and these effects were mediated by the disruption of nuclear factor erythroid 2-related factor 2 (Nrf 2)/p62 pathway. Taken together, these findings suggested that the cytotoxic effect of isoaaptamine is associated with the induction of apoptosis and autophagy through oxidative stress. Our data indicated that isoaaptamine represents an interesting drug lead in the war against breast cancer. Full article

(This article belongs to the Special Issue In Vitro and In Vivo Approaches in the Driving Seat of Marine Drugs Discovery)

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10 pages, 1876 KiB

Open AccessCommunication

Difference in Uptake of Tetrodotoxin and Saxitoxins into Liver Tissue Slices among Pufferfish, Boxfish and Porcupinefish

by Yuji Nagashima, Akira Ohta, Xianzhe Yin, Shoichiro Ishizaki, Takuya Matsumoto, Hiroyuki Doi and Toshiaki Ishibashi

Mar. Drugs 2018, 16(1), 17; https://doi.org/10.3390/md16010017 - 8 Jan 2018

Cited by 19 | Viewed by 5542

Abstract

Although pufferfish of the family Tetraodontidae contain high levels of tetrodotoxin (TTX) mainly in the liver, some species of pufferfish, boxfish of the family Ostraciidae, and porcupinefish of the family Diodontidae do not. To clarify the mechanisms, uptake of TTX and saxitoxins (STXs) [...] Read more.

Although pufferfish of the family Tetraodontidae contain high levels of tetrodotoxin (TTX) mainly in the liver, some species of pufferfish, boxfish of the family Ostraciidae, and porcupinefish of the family Diodontidae do not. To clarify the mechanisms, uptake of TTX and saxitoxins (STXs) into liver tissue slices of pufferfish, boxfish and porcupinefish was examined. Liver tissue slices of the pufferfish (toxic species Takifugu rubripes and non-toxic species Lagocephalus spadiceus, L. cheesemanii and Sphoeroides pachygaster) incubated with 50 µM TTX accumulated TTX (0.99–1.55 µg TTX/mg protein) after 8 h, regardless of the toxicity of the species. In contrast, in liver tissue slices of boxfish (Ostracion immaculatus) and porcupinefish (Diodon holocanthus, D. liturosus, D. hystrix and Chilomycterus reticulatus), TTX content did not increase with incubation time, and was about 0.1 µg TTX/mg protein. When liver tissue slices were incubated with 50 µM STXs for 8 h, the STXs content was <0.1 µg STXs/mg protein, irrespective of the fish species. These findings indicate that, like the toxic species of pufferfish T. rubripes, non-toxic species such as L. spadiceus, L. cheesemanii and S. pachygaster, potentially take up TTX into the liver, while non-toxic boxfish and porcupinefish do not take up either TTX or STXs. Full article

(This article belongs to the Special Issue Tetrodotoxin)

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16 pages, 10226 KiB

Open AccessArticle

Effect of Low Molecular Weight Oligopeptides Isolated from Sea Cucumber on Diabetic Wound Healing in db/db Mice

by Di Li, Lin Li, Teng Xu, Tianxing Wang, Jinwei Ren, Xinran Liu and Yong Li

Mar. Drugs 2018, 16(1), 16; https://doi.org/10.3390/md16010016 - 8 Jan 2018

Cited by 30 | Viewed by 5943

Abstract

Impaired wound healing is a major clinical problem in patients with diabetes and is the leading cause of lower limb amputation. This study is aimed to observe the effects of small molecule oligopeptides isolated from sea cucumber (SCCOPs) on the wound healing process [...] Read more.

Impaired wound healing is a major clinical problem in patients with diabetes and is the leading cause of lower limb amputation. This study is aimed to observe the effects of small molecule oligopeptides isolated from sea cucumber (SCCOPs) on the wound healing process in diabetic mice. Ninety db/db male mice were divided into five groups, including the model control group, whey protein group (0.50 g/kg) and three SCCOPs dose groups (0.25 g/kg, 0.50 g/kg and 1.00 g/kg). Additionally, 18 db/m male mice were used as normal control group. After full-thickness incisions on the dorsum, mice in SCCOPs-treated groups were intragastrically administered SCCOPs, while others were administered vehicle or whey protein. Mice were sacrificed on days 4, 7 and 14. The wound healing condition, inflammatory response, angiogenesis, collagen deposition, oxidative stress and nutritional status were evaluated. A pathological report showed increased vascularisation, collagen deposition and epithelialisation in SCCOPs-treated groups. SCCOPs-treated mice showed decreased C-reactive protein (CRP), interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-α, chemokine (C-C motif) ligand 2 (CCL2) and reactive oxygen species (ROS) contents, and increased IL-10, stromal cell-derived factor-1 alpha (SDF-1α), nitric oxide (NO), albumin (ALB), prealbumin (PA) and transferrin (TRF) levels and vascular endothelial growth factor (VEGF) expression. All parameters were significant (p < 0.05) in comparison to model control group. These results suggest that treatment with SCCOPs can promote significant wound healing in diabetic mice. Full article

(This article belongs to the Special Issue Nutraceuticals and Functional Foods)

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12 pages, 3991 KiB

Open AccessArticle

Aquaculture Soft Coral Lobophytum crassum as a Producer of Anti-Proliferative Cembranoids

by Bo-Rong Peng, Mei-Chin Lu, Mohamed El-Shazly, Shwu-Li Wu, Kuei-Hung Lai and Jui-Hsin Su

Mar. Drugs 2018, 16(1), 15; https://doi.org/10.3390/md16010015 - 7 Jan 2018

Cited by 18 | Viewed by 6313

Abstract

Our continuous search for marine bioactive secondary metabolites led to the screening of crude extracts from a variety of aquaculture soft corals. The ethyl acetate (EtOAc) extract of Lobophytum crassum showed a distinctive chemical profile that was different from the wild type. It [...] Read more.

Our continuous search for marine bioactive secondary metabolites led to the screening of crude extracts from a variety of aquaculture soft corals. The ethyl acetate (EtOAc) extract of Lobophytum crassum showed a distinctive chemical profile that was different from the wild type. It demonstrated significant anti-proliferative activity against Molt 4 leukemia cell with an IC₅₀ value of 1 μg/mL after 24 h. Chemical investigation focusing on the unique peaks in L. crassum profile led to the discovery of a new α-tocopherol crassumtocopherol C (1), and two new cembrane-based diterpenoids culobophylins D (2) and E (3), along with ten known cembranoids (4–13). The structures of these isolates were elucidated using extensive spectroscopic techniques and a comparison with previously published data of related metabolites. Compound 2 was found to possess the first identified saturated internal C₄-O-C₁₄ linkage six-membered ring among all cembrane-type diterpenoids. The anti-proliferative activity of all the isolates (except 3) was evaluated against a limited panel of leukemia cell lines (Molt 4, K562, U937, and Sup-T1). The major compounds 8 and 10 exhibited the most anti-proliferative potent effect, with IC₅₀ values ranging from 1.2 to 7.1 μM. The Structure Activity Relationship (SAR) of the isolates suggested that the presence of lactone moieties is crucial for the anti-proliferative activity against leukemia cells. Our work indicated that the development of an efficient aquaculture protocols for soft corals led to the discovery of new secondary metabolites with unique structural features. Such protocols can lead to a sustainable supply of biologically active compounds in enough quantities for the pharmaceutical industry. Full article

(This article belongs to the Special Issue Natural Products from Coral Reef Organisms)

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15 pages, 9691 KiB

Open AccessFeature PaperReview

Secondary Metabolites of Mangrove-Associated Strains of Talaromyces

by Rosario Nicoletti, Maria Michela Salvatore and Anna Andolfi

Mar. Drugs 2018, 16(1), 12; https://doi.org/10.3390/md16010012 - 6 Jan 2018

Cited by 56 | Viewed by 6861

Abstract

Boosted by the general aim of exploiting the biotechnological potential of the microbial component of biodiversity, research on the secondary metabolite production of endophytic fungi has remarkably increased in the past few decades. Novel compounds and bioactivities have resulted from this work, which [...] Read more.

Boosted by the general aim of exploiting the biotechnological potential of the microbial component of biodiversity, research on the secondary metabolite production of endophytic fungi has remarkably increased in the past few decades. Novel compounds and bioactivities have resulted from this work, which has stimulated a more thorough consideration of various natural ecosystems as conducive contexts for the discovery of new drugs. Thriving at the frontier between land and sea, mangrove forests represent one of the most valuable areas in this respect. The present paper offers a review of the research on the characterization and biological activities of secondary metabolites from manglicolous strains of species belonging to the genus Talaromyces. Aspects concerning the opportunity for a more reliable identification of this biological material in the light of recent taxonomic revisions are also discussed. Full article

(This article belongs to the Special Issue Bioactive Compounds from Marine-Derived Aspergillus, Penicillium, Talaromyces and Trichoderma Species)

9 pages, 2447 KiB

Open AccessArticle

Suppression of RANKL-Induced Osteoclastogenesis by the Metabolites from the Marine Fungus Aspergillus flocculosus Isolated from a Sponge Stylissa sp.

by Hee Jae Shin, Byeoung-Kyu Choi, Phan Thi Hoai Trinh, Hwa-Sun Lee, Jong Soon Kang, Tran Thi Thanh Van, Hyi-Seung Lee, Jong Seok Lee, Yeon-Ju Lee and Jihoon Lee

Mar. Drugs 2018, 16(1), 14; https://doi.org/10.3390/md16010014 - 5 Jan 2018

Cited by 26 | Viewed by 5512

Abstract

A new α-pyrone merosesquiterpenoid possessing an angular tetracyclic carbon skeleton, ochraceopone F (1), and four known secondary metabolites, aspertetranone D (2), cycloechinulin (3), wasabidienone E (4), and mactanamide (5), were isolated from the [...] Read more.

A new α-pyrone merosesquiterpenoid possessing an angular tetracyclic carbon skeleton, ochraceopone F (1), and four known secondary metabolites, aspertetranone D (2), cycloechinulin (3), wasabidienone E (4), and mactanamide (5), were isolated from the marine fungus Aspergillus flocculosus derived from a sponge Stylissa sp. collected in Vietnam. The structures of Compounds 1–5 were elucidated by analysis of 1D and 2D NMR spectra and MS data. All the isolated compounds were evaluated for anti-proliferation activity and their suppression effects on receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclast differentiation using tartate-resisant acid phosphatase (TRAP). Compounds 1–5 had no anti-proliferative effect on human cancer cell lines up to 30 μg/mL. Among these compounds, aspertetranone D (2) and wasabidienone E (4) exhibited weak osteoclast differentiation inhibitory activity at 10 μg/mL. However, mactanamide (5) showed a potent suppression effect of osteoclast differentiation without any evidence of cytotoxicity. Full article

(This article belongs to the Special Issue Marine Natural Products and Their Translational Applications in Medicine)

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16 pages, 2140 KiB

Open AccessArticle

Functional Expression and Characterization of the Recombinant N-Acetyl-Glucosamine/N-Acetyl-Galactosamine-Specific Marine Algal Lectin BPL3

by Hyun-Ju Hwang, Jin-Woo Han, Gwang Hoon Kim and Jong Won Han

Mar. Drugs 2018, 16(1), 13; https://doi.org/10.3390/md16010013 - 5 Jan 2018

Cited by 7 | Viewed by 4817

Abstract

Lectins, characterized by their carbohydrate-binding ability, have extensive practical applications. However, their industrial use is limited due to impurity. Thus, quality-controlled production of recombinant lectin is necessary. In this study, the algal lectin BPL3 (Bryopsis plumosa lectin 3) was successfully produced using [...] Read more.

Lectins, characterized by their carbohydrate-binding ability, have extensive practical applications. However, their industrial use is limited due to impurity. Thus, quality-controlled production of recombinant lectin is necessary. In this study, the algal lectin BPL3 (Bryopsis plumosa lectin 3) was successfully produced using a bacterial expression system, BL21(DE3), with an artificial repeated structure (dimeric construct). Recombinant dimeric BPL3 (rD2BPL3) was confirmed by LC-MS/MS spectrometry. Expression efficiency was greater for the construct with the repeat structure (rD2BPL3) than the monomeric form (rD1BPL3). Optimal conditions for expression were 1 mM IPTG at 20 °C. Recombinant lectin was purified under denaturing conditions and refolded by the flash dilution method. Recombinant BPL3 was solubilized in 1× PBS containing 2 M urea. rD2BPL3 showed strong hemagglutination activity using human erythrocyte. rD2BPL3 had a similar sugar specificity to that of the native protein, i.e., to N-acetyl-glucosamine (GlcNAc) and N-acetyl-galactosamine (GalNAc). Glycan array results showed that recombinant BPL3 and native BPL3 exhibited different binding properties. Both showed weak binding activity to α-Man-Sp. Native BPL3 showed strong binding specificity to the alpha conformation of amino sugars, and rD2BPL3 had binding activity to the beta conformation. The process developed in this study was suitable for the quality-controlled large-scale production of recombinant lectins. Full article

(This article belongs to the Special Issue Marine Drugs Interact with Functional Proteins)

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9 pages, 1172 KiB

Open AccessArticle

The Suppressive Activity of Fucofuroeckol-A Derived from Brown Algal Ecklonia stolonifera Okamura on UVB-Induced Mast Cell Degranulation

by Thanh Sang Vo, Se-Kwon Kim, BoMi Ryu, Dai Hung Ngo, Na-Young Yoon, Long Giang Bach, Nguyen Thi Nhat Hang and Dai Nghiep Ngo

Mar. Drugs 2018, 16(1), 1; https://doi.org/10.3390/md16010001 - 4 Jan 2018

Cited by 60 | Viewed by 5709

Abstract

UV light, especially UVB, is known as a trigger of allergic reaction, leading to mast cell degranulation and histamine release. In this study, phlorotannin Fucofuroeckol-A (F-A) derived from brown algal Ecklonia stolonifera Okamura was evaluated for its protective capability against UVB-induced allergic reaction [...] Read more.

UV light, especially UVB, is known as a trigger of allergic reaction, leading to mast cell degranulation and histamine release. In this study, phlorotannin Fucofuroeckol-A (F-A) derived from brown algal Ecklonia stolonifera Okamura was evaluated for its protective capability against UVB-induced allergic reaction in RBL-2H3 mast cells. It was revealed that F-A significantly suppress mast cell degranulation via decreasing histamine release as well as intracellular Ca²⁺ elevation at the concentration of 50 μM. Moreover, the inhibitory effect of F-A on IL-1β and TNF-α productions was also evidenced. Notably, the protective activity of F-A against mast cell degranulation was found due to scavenging ROS production. Accordingly, F-A from brown algal E. stolonifera was suggested to be promising candidate for its protective capability against UVB-induced allergic reaction. Full article

(This article belongs to the Special Issue Anti-Photoagaing and Photo-Protective Compounds from Marine Organisms)

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8 pages, 5950 KiB

Open AccessArticle

Formation of Silver Nanoparticles Using Fluorescence Properties of Chitosan Oligomers

by Ja Young Cheon, Hun Min Lee and Won Ho Park

Mar. Drugs 2018, 16(1), 11; https://doi.org/10.3390/md16010011 - 3 Jan 2018

Cited by 5 | Viewed by 4432

Abstract

In this study, silver chloride nanoparticles (AgCl NPs) were prepared using chitosan oligomer (CHI) and chitosan oligomer derivatives (CHI-FITC). The CHI and CHI-FITC were used as markers to confirm the formation of AgCl NPs using their fluorescence properties as well as stabilizers. The [...] Read more.

In this study, silver chloride nanoparticles (AgCl NPs) were prepared using chitosan oligomer (CHI) and chitosan oligomer derivatives (CHI-FITC). The CHI and CHI-FITC were used as markers to confirm the formation of AgCl NPs using their fluorescence properties as well as stabilizers. The fluorescence properties of CHI and CHI-FITC were monitored by a luminescence spectrophotometer, and the morphology of the AgCl NPs was further confirmed by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The fluorescence of CHI and CHI-FITC was quenched by the formation of AgCl NPs, and the Stern–Volmer equation was used to compare the two types of stabilizer. The CHI and CHI-FITC stabilizer were linear and nonlinear, respectively, with respect to the Stern–Volmer equation, and considered to be usable as fluorescence indicators to confirm the formation behavior of AgCl NPs through fluorescence quenching. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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14 pages, 1265 KiB

Open AccessArticle

Eicosanoid Diversity of Stony Corals

by Helike Lõhelaid and Nigulas Samel

Mar. Drugs 2018, 16(1), 10; https://doi.org/10.3390/md16010010 - 3 Jan 2018

Cited by 10 | Viewed by 4229

Abstract

Oxylipins are well-established lipid mediators in plants and animals. In mammals, arachidonic acid (AA)-derived eicosanoids control inflammation, fever, blood coagulation, pain perception and labor, and, accordingly, are used as drugs, while lipoxygenases (LOX), as well as cyclooxygenases (COX) serve as therapeutic targets for [...] Read more.

Oxylipins are well-established lipid mediators in plants and animals. In mammals, arachidonic acid (AA)-derived eicosanoids control inflammation, fever, blood coagulation, pain perception and labor, and, accordingly, are used as drugs, while lipoxygenases (LOX), as well as cyclooxygenases (COX) serve as therapeutic targets for drug development. In soft corals, eicosanoids are synthesized on demand from AA by LOX, COX, and catalase-related allene oxide synthase-lipoxygenase (cAOS-LOX) and hydroperoxide lyase-lipoxygenase (cHPL-LOX) fusion proteins. Reef-building stony corals are used as model organisms for the stress-related genomic studies of corals. Yet, the eicosanoid synthesis capability and AA-derived lipid mediator profiles of stony corals have not been determined. In the current study, the genomic and transcriptomic data about stony coral LOXs, AOS-LOXs, and COXs were analyzed and the eicosanoid profiles and AA metabolites of three stony corals, Acropora millepora, A. cervicornis, and Galaxea fascicularis, were determined by reverse-phase high-performance liquid chromatography (RP-HPLC) coupled with MS-MS and a radiometric detector. Our results confirm that the active LOX and AOS-LOX pathways are present in Acropora sp., which correspond to the genomic/sequence data reported earlier. In addition, LOX, AOS-LOX, and COX products were detected in the closely related species G. fascicularis. In conclusion, the functional 8R-LOX and/or AOS-LOX pathways are abundant among corals, while COXs are restricted to certain soft and stony coral lineages. Full article

(This article belongs to the Special Issue Marine Small-Molecule Bioactive Agents and Therapeutic Targets)

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