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Marine Drugs
Volume 20
Issue 12
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Mar. Drugs, Volume 20, Issue 12 (December 2022) – 61 articles

Cover Story (view full-size image): Marine macroalgae (seaweeds) are considered an untapped source of healthy natural metabolites, and their market demand is rapidly increasing. In order to thrive under changing environmental conditions, intertidal macroalgae have developed chemical defense mechanisms, including the synthesis of a wide variety of unique bioactive compounds that can be used for human benefit. We present an original two-phase multitrophic aquaculture system, designed to direct seaweed metabolic responses to enhance the production of target antioxidant and photoprotective biomaterials. Our integrated cultivation plan offers a sustainable approach, with the potential to be adopted by emerging industries for food and health applications. View this paper
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22 pages, 1658 KiB  
Review
Macroalgae Specialized Metabolites: Evidence for Their Anti-Inflammatory Health Benefits
by Djenisa H. A. Rocha, Diana C. G. A. Pinto and Artur M. S. Silva
Mar. Drugs 2022, 20(12), 789; https://doi.org/10.3390/md20120789 - 19 Dec 2022
Cited by 15 | Viewed by 2702
Abstract
Inflammation is an organism’s response to chemical or physical injury. It is split into acute and chronic inflammation and is the last, most significant cause of death worldwide. Nowadays, according to the World Health Organization (WHO), the greatest threat to human health is [...] Read more.
Inflammation is an organism’s response to chemical or physical injury. It is split into acute and chronic inflammation and is the last, most significant cause of death worldwide. Nowadays, according to the World Health Organization (WHO), the greatest threat to human health is chronic disease. Worldwide, three out of five people die from chronic inflammatory diseases such as stroke, chronic respiratory diseases, heart disorders, and cancer. Nowadays, anti-inflammatory drugs (steroidal and non-steroidal, enzyme inhibitors that are essential in the inflammatory process, and receptor antagonists, among others) have been considered as promising treatments to be explored. However, there remains a significant proportion of patients who show poor or incomplete responses to these treatments or experience associated severe side effects. Seaweeds represent a valuable resource of bioactive compounds associated with anti-inflammatory effects and offer great potential for the development of new anti-inflammatory drugs. This review presents an overview of specialized metabolites isolated from seaweeds with in situ and in vivo anti-inflammatory properties. Phlorotannins, carotenoids, sterols, alkaloids, and polyunsaturated fatty acids present significant anti-inflammatory effects given that some of them are involved directly or indirectly in several inflammatory pathways. The majority of the isolated compounds inhibit the pro-inflammatory mediators/cytokines. Studies have suggested an excellent selectivity of chromene nucleus towards inducible pro-inflammatory COX-2 than its constitutive isoform COX-1. Additional research is needed to understand the mechanisms of action of seaweed’s compounds in inflammation, given the production of sustainable and healthier anti-inflammatory agents. Full article
(This article belongs to the Special Issue Seaweed Bioactive Metabolites: Health Benefits and Potential Applications)
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15 pages, 1912 KiB  
Article
Structural Characterization and Spatial Mapping of Tetrodotoxins in Australian Polyclads
by Justin M. McNab, Matthew T. Briggs, Jane E. Williamson, Peter Hoffmann, Jorge Rodriguez and Peter Karuso
Mar. Drugs 2022, 20(12), 788; https://doi.org/10.3390/md20120788 - 19 Dec 2022
Cited by 4 | Viewed by 2403
Abstract
Tetrodotoxin (TTX) is a potent marine neurotoxin that occurs in several Australian phyla, including pufferfish, toadfish, gobies, and the blue-ringed octopus. These animals are partially immune, and TTX is known to bioaccumulate and subject to trophic transfer. As such, it could be more [...] Read more.
Tetrodotoxin (TTX) is a potent marine neurotoxin that occurs in several Australian phyla, including pufferfish, toadfish, gobies, and the blue-ringed octopus. These animals are partially immune, and TTX is known to bioaccumulate and subject to trophic transfer. As such, it could be more ubiquitously distributed in animals than is currently known. Flatworms of the order Polycladida are commonly occurring invertebrates in intertidal ecosystems and are especially diverse in Australian waters. While TTX has been identified in polyclads from Japan and New Zealand, Australian species have yet to be tested. In this study, several eastern Australian polyclad flatworm species from the suborders Cotylea and Acotylea were tested for TTX and analogs by HILIC-HRMS to understand the distribution of this toxin within these suborders. Herein, we report the detection of TTX and some known analogs in polyclad species, one of which is a pest to shellfish aquaculture. We also report, for the first time, the application of MALDI mass spectrometry imaging utilized to map TTX spatially within the intestinal system of polyclads. The identification of TTX and its analogs in Australian flatworms illustrates a broader range of toxic flatworms and highlights that analogs are important to consider when studying the distributions of toxins in animals. Full article
(This article belongs to the Section Marine Toxins)
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18 pages, 4078 KiB  
Article
Complexes of Cu–Polysaccharide of a Marine Red Microalga Produce Spikes with Antimicrobial Activity
by Nofar Yehuda, Levi A. Gheber, Ariel Kushmaro and Shoshana (Mails) Arad
Mar. Drugs 2022, 20(12), 787; https://doi.org/10.3390/md20120787 - 19 Dec 2022
Cited by 2 | Viewed by 4253
Abstract
Metal–polysaccharides have recently raised significant interest due to their multifunctional bioactivities. The antimicrobial activity of a complex of Cu2O with the sulfated polysaccharide (PS) of the marine red microalga Porphyridium sp. was previously attributed to spikes formed on the complex surface [...] Read more.
Metal–polysaccharides have recently raised significant interest due to their multifunctional bioactivities. The antimicrobial activity of a complex of Cu2O with the sulfated polysaccharide (PS) of the marine red microalga Porphyridium sp. was previously attributed to spikes formed on the complex surface (roughness). This hypothesis was further examined here using other Cu–PS complexes (i.e., monovalent-Cu2O, CuCl and divalent-CuO, CuCl2). The nanostructure parameters of the monovalent complexes, namely, longer spikes (1000 nm) and greater density (2000–5000 spikes/µm2) were found to be related to the superior inhibition of microbial growth and viability and biofilm formation. When Escherichia coli TV1061, used as a bioluminescent test organism, was exposed to the monovalent Cu–PS complexes, enhanced bioluminescence accumulation was observed, probably due to membrane perforation by the spikes on the surface of the complexes and consequent cytoplasmic leakage. In addition, differences were found in the surface chemistry of the monovalent and divalent Cu–PS complexes, with the monovalent Cu–PS complexes exhibiting greater stability (ζ-potential, FTIR spectra, and leaching out), which could be related to spike formation. This study thus supports our hypothesis that the spikes protruding from the monovalent Cu–PS surfaces, as characterized by their aspect ratio, are responsible for the antimicrobial and antibiofilm activities of the complexes. Full article
(This article belongs to the Collection Marine Polysaccharides)
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18 pages, 2721 KiB  
Article
Polyphenolic Compounds Isolated from Marine Algae Attenuate the Replication of SARS-CoV-2 in the Host Cell through a Multi-Target Approach of 3CLpro and PLpro
by D. P. Nagahawatta, N. M. Liyanage, Jun-Geon Je, H. H. A. C. K. Jayawardhana, Thilina U. Jayawardena, Seong-Hun Jeong, Hyung-Jun Kwon, Cheol Soo Choi and You-Jin Jeon
Mar. Drugs 2022, 20(12), 786; https://doi.org/10.3390/md20120786 - 19 Dec 2022
Cited by 14 | Viewed by 2713
Abstract
A global health concern has emerged as a response to the recent SARS-CoV-2 pandemic. The identification and inhibition of drug targets of SARS-CoV-2 is a decisive obligation of scientists. In addition to the cell entry mechanism, SARS-CoV-2 expresses a complicated replication mechanism that [...] Read more.
A global health concern has emerged as a response to the recent SARS-CoV-2 pandemic. The identification and inhibition of drug targets of SARS-CoV-2 is a decisive obligation of scientists. In addition to the cell entry mechanism, SARS-CoV-2 expresses a complicated replication mechanism that provides excellent drug targets. Papain-like protease (PLpro) and 3-chymotrypsin-like protease (3CLpro) play a vital role in polyprotein processing, producing functional non-structural proteins essential for viral replication and survival in the host cell. Moreover, PLpro is employed by SARS-CoV-2 for reversing host immune responses. Therefore, if some particular compound has the potential to interfere with the proteolytic activities of 3CLpro and PLpro of SARS-CoV-2, it may be effective as a treatment or prophylaxis for COVID-19, reducing viral load, and reinstating innate immune responses. Thus, the present study aims to inhibit SARS-CoV-2 through 3CLpro and PLpro using marine natural products isolated from marine algae that contain numerous beneficial biological activities. Molecular docking analysis was utilized in the present study for the initial screening of selected natural products depending on their 3CLpro and PLpro structures. Based on this approach, Ishophloroglucin A (IPA), Dieckol, Eckmaxol, and Diphlorethohydroxycarmalol (DPHC) were isolated and used to perform in vitro evaluations. IPA presented remarkable inhibitory activity against interesting drug targets. Moreover, Dieckol, Eckmaxol, and DPHC also expressed significant potential as inhibitors. Finally, the results of the present study confirm the potential of IPA, Dieckol, Eckmaxol, and DPHC as inhibitors of SARS-CoV-2. To the best of our knowledge, this is the first study that assesses the use of marine natural products as a multifactorial approach against 3CLpro and PLpro of SARS-CoV-2. Full article
(This article belongs to the Special Issue Marine-Derived Natural Products with Potential Benefits on Human and Animal Health: Tackling Pathogenic Virus, Protozoal and MDR-Bacteria)
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16 pages, 1417 KiB  
Article
Fillet Fish Fortified with Algal Extracts of Codium tomentosum and Actinotrichia fragilis, as a Potential Antibacterial and Antioxidant Food Supplement
by Mohamed S. M. Abd El Hafez, Sarah H. Rashedy, Neveen M. Abdelmotilib, Hala E. Abou El-Hassayeb, João Cotas and Leonel Pereira
Mar. Drugs 2022, 20(12), 785; https://doi.org/10.3390/md20120785 - 17 Dec 2022
Cited by 7 | Viewed by 3533
Abstract
With respect to the potential natural resources in the marine environment, marine macroalgae or seaweeds are recognized to have health impacts. Two marine algae that are found in the Red Sea, Codium tomentosum (Green algae) and Actinotrichia fragilis (Red algae), were collected. Antibacterial [...] Read more.
With respect to the potential natural resources in the marine environment, marine macroalgae or seaweeds are recognized to have health impacts. Two marine algae that are found in the Red Sea, Codium tomentosum (Green algae) and Actinotrichia fragilis (Red algae), were collected. Antibacterial and antioxidant activities of aqueous extracts of these algae were evaluated in vitro. Polyphenols from the extracts were determined using HPLC. Fillet fish was fortified with these algal extracts in an attempt to improve its nutritional value, and sensory evaluation was performed. The antibacterial effect of C. tomentosum extract was found to be superior to that of A. fragilis extract. Total phenolic contents of C. tomentosum and A. fragilis aqueous extract were 32.28 ± 1.63 mg/g and 19.96 ± 1.28 mg/g, respectively, while total flavonoid contents were 4.54 ± 1.48 mg/g and 3.86 ± 1.02 mg/g, respectively. Extract of C. tomentosum demonstrates the highest antioxidant activity, with an IC50 value of 75.32 ± 0.07 μg/mL. The IC50 of L-ascorbic acid as a positive control was 22.71 ± 0.03 μg/mL. The IC50 values for inhibiting proliferation on normal PBMC cells were 33.7 ± 1.02 µg/mL and 51.0 ± 1.14 µg/mL for C. tomentosum and A. fragilis, respectively. The results indicated that both algal aqueous extracts were safe, with low toxicity to normal cells. Interestingly, fillet fish fortified with C. tomentosum extract demonstrated the greatest overall acceptance score. These findings highlight the potential of these seaweed species for cultivation as a sustainable and safe source of therapeutic compounds for treating human and fish diseases, as well as effective food supplements and preservatives instead of chemical ones after performing in vivo assays. Full article
(This article belongs to the Special Issue Characterization of Bioactive Components in Edible Algae 3rd Edition)
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16 pages, 687 KiB  
Review
Antidiabetic Properties of Chitosan and Its Derivatives
by Huei-Ping Tzeng, Shing-Hwa Liu and Meng-Tsan Chiang
Mar. Drugs 2022, 20(12), 784; https://doi.org/10.3390/md20120784 - 17 Dec 2022
Cited by 18 | Viewed by 3592
Abstract
Diabetes mellitus is a chronic metabolic disorder. In addition to taking medication, adjusting the composition of the diet is also considered one of the effective methods to control the levels of blood glucose. Chitosan and its derivatives are natural and versatile biomaterials with [...] Read more.
Diabetes mellitus is a chronic metabolic disorder. In addition to taking medication, adjusting the composition of the diet is also considered one of the effective methods to control the levels of blood glucose. Chitosan and its derivatives are natural and versatile biomaterials with health benefits. Chitosan has the potential to alleviate diabetic hyperglycemia by reducing hepatic gluconeogenesis and increasing skeletal muscle glucose uptake and utility. Scientists also focus on the glucose-lowering effect of chitosan oligosaccharide (COS). COS supplementation has the potential to alleviate abnormal glucose metabolism in diabetic rats by inhibiting gluconeogenesis and lipid peroxidation in the liver. Both high and low molecular weight chitosan feeding reduced insulin resistance by inhibiting lipid accumulation in the liver and adipose tissue and ameliorating chronic inflammation in diabetic rats. COS can reduce insulin resistance but has less ability to reduce hepatic lipids in diabetic rats. A clinical trial showed that a 3-month administration of chitosan increased insulin sensitivity and decreased body weight and triglycerides in obese patients. Chitosan and COS are considered Generally Recognized as Safe; however, they are still considered to be of safety concerns. This review highlights recent advances of chitosan and its derivatives in the glucose-lowering/antidiabetic effects and the safety. Full article
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13 pages, 3593 KiB  
Article
A Novel κ-Carrageenase from Marine Bacterium Rhodopirellula sallentina SM41: Heterologous Expression, Biochemical Characterization and Salt-Tolerance Mechanism Investigation
by Yong-Hui Zhang, Yi-Ying Chen, Xiao-Yan Zhuang, Qiong Xiao, Jun Chen, Fu-Quan Chen, Qiu-Ming Yang, Hui-Fen Weng, Bai-Shan Fang and An-Feng Xiao
Mar. Drugs 2022, 20(12), 783; https://doi.org/10.3390/md20120783 - 16 Dec 2022
Cited by 7 | Viewed by 2191
Abstract
κ-carrageenases are members of the glycoside hydrolase family 16 (GH16) that hydrolyze sulfated galactans in red algae, known as κ-carrageenans. In this study, a novel κ-carrageenase gene from the marine bacterium Rhodopirellula sallentina SM41 (RsCgk) was discovered via the genome mining approach. There [...] Read more.
κ-carrageenases are members of the glycoside hydrolase family 16 (GH16) that hydrolyze sulfated galactans in red algae, known as κ-carrageenans. In this study, a novel κ-carrageenase gene from the marine bacterium Rhodopirellula sallentina SM41 (RsCgk) was discovered via the genome mining approach. There are currently no reports on κ-carrageenase from the Rhodopirellula genus, and RsCgk shares a low identity (less than 65%) with κ- carrageenase from other genera. The RsCgk was heterologously overexpressed in Escherichia coli BL21 and characterized for its enzymatic properties. RsCgk exhibited maximum activity at pH 7.0 and 40 °C, and 50% of its initial activity was retained after incubating at 30 °C for 2 h. More than 70% of its activity was maintained after incubation at pH 6.0–8.0 and 4 °C for 24 h. As a marine derived enzyme, RsCgk showed excellent salt tolerance, retaining full activity in 1.2 M NaCl, and the addition of NaCl greatly enhanced its thermal stability. Mass spectrometry analysis of the RsCgk hydrolysis products revealed that the enzyme had high degradation specificity and mainly produced κ-carrageenan disaccharide. Comparative molecular dynamics simulations revealed that the conformational changes of tunnel-forming loops under salt environments may cause the deactivation or stabilization of RsCgk. Our results demonstrated that RsCgk could be utilized as a potential tool enzyme for efficient production of κ-carrageenan oligosaccharides under high salt conditions. Full article
(This article belongs to the Special Issue Seaweed-Degrading Enzymes, Functions and Applications of Their Products)
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14 pages, 1407 KiB  
Review
Chitosan-Based Carbon Dots with Applied Aspects: New Frontiers of International Interest in a Material of Marine Origin
by Angel M. Villalba-Rodríguez, Reyna Berenice González-González, Manuel Martínez-Ruiz, Elda A. Flores-Contreras, María Fernanda Cárdenas-Alcaide, Hafiz M. N. Iqbal and Roberto Parra-Saldívar
Mar. Drugs 2022, 20(12), 782; https://doi.org/10.3390/md20120782 - 16 Dec 2022
Cited by 13 | Viewed by 3142
Abstract
Carbon dots (CDs) have attracted significant research attention worldwide due to their unique properties and advantageous attributes, such as superior optical properties, biocompatibility, easy surface functionalization, and more. Moreover, biomass-derived CDs have attracted much attention because of their additional advantages related to more [...] Read more.
Carbon dots (CDs) have attracted significant research attention worldwide due to their unique properties and advantageous attributes, such as superior optical properties, biocompatibility, easy surface functionalization, and more. Moreover, biomass-derived CDs have attracted much attention because of their additional advantages related to more environmentally friendly and lower-cost synthesis. In this respect, chitosan has been recently explored for the preparation of CDs, which in comparison to other natural precursors exhibited additional advantages. Beyond the benefits related to the eco-friendly and abundant nature of chitosan, using it as a nanomaterial precursor offers additional benefits in terms of structure, morphology, and dopant elements. Furthermore, the high content of nitrogen in chitosan allows it to be used as a single carbon and nitrogen precursor for the preparation of N-doped CDs, significantly improving their fluorescent properties and, therefore, their performances. This review addresses the most recent advances in chitosan-based CDs with a special focus on synthesis methods, enhanced properties, and their applications in different fields, including biomedicine, the environment, and food packaging. Finally, this work also addresses the key challenges to be overcome to propose future perspectives and research to unlock their great potential for practical applications. Full article
(This article belongs to the Section Biomaterials of Marine Origin)
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13 pages, 895 KiB  
Article
Functional Properties of Dunaliella salina and Its Positive Effect on Probiotics
by Ivana Hyrslova, Gabriela Krausova, Iva Mrvikova, Barbora Stankova, Tomas Branyik, Hana Malinska, Martina Huttl, Antonin Kana and Ivo Doskocil
Mar. Drugs 2022, 20(12), 781; https://doi.org/10.3390/md20120781 - 15 Dec 2022
Cited by 14 | Viewed by 4053
Abstract
The unicellular green microalga Dunaliella is a potential source of a wide range of nutritionally important compounds applicable to the food industry. The aim of this study was to assess the effect of Dunaliella salina dried biomass on the growth and adherence of [...] Read more.
The unicellular green microalga Dunaliella is a potential source of a wide range of nutritionally important compounds applicable to the food industry. The aim of this study was to assess the effect of Dunaliella salina dried biomass on the growth and adherence of 10 strains of Lactobacillus, Lacticaseibacillus, and Bifidobacterium. The immunomodulatory, antioxidant, and cytotoxic effects of D. salina on human peripheral mononuclear cells and simulated intestinal epithelial cell lines Caco-2 and HT-29 were evaluated. Furthermore, the hypocholesterolemic effects of the microalgae on lipid metabolism in rats fed a high-fat diet were analyzed. The addition of D. salina biomass had a positive effect on the growth of nine out of 10 probiotics and promoted the adherence of three bifidobacteria strains to human cell lines. The antioxidant and immunomodulatory properties of D. salina were concentration-dependent. The inflammatory cytokines (TNF-α and IL-6) were significantly increased following Dunaliella stimulation at the lowest concentration (0.5% w/v). Eight week supplementation of D. salina to the diet of hypercholesteromic rats significantly decreased the serum concentrations of LDL-C, VLDL, IDL-B, and IDL-C. D. salina is not cytotoxic in intestinal cell models; it promotes adherence of selected bifidobacteria, it affords immunomodulatory and antioxidant effects, and its addition to diets may help decrease atherosclerosis risk factors. Full article
(This article belongs to the Special Issue Marine Natural Products, Gut Microbiota and Health Benefits)
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26 pages, 4838 KiB  
Article
Characterization and Optimization of Culture Conditions for Aurantiochytrium sp. SC145 Isolated from Sand Cay (Son Ca) Island, Vietnam, and Antioxidative and Neuroprotective Activities of Its Polyunsaturated Fatty Acid Mixture
by Hoang Thi Minh Hien, Le Thi Thom, Nguyen Cam Ha, Luu Thi Tam, Ngo Thi Hoai Thu, Tru Van Nguyen, Vu Thi Loan, Nguyen Trong Dan and Dang Diem Hong
Mar. Drugs 2022, 20(12), 780; https://doi.org/10.3390/md20120780 - 14 Dec 2022
Cited by 7 | Viewed by 2534
Abstract
Aurantiochytrium is a heterotrophic marine microalga that has potential industrial applications. The main objectives of this study were to isolate an Aurantiochytrium strain from Sand Cay (Son Ca) Island, Vietnam, optimize its culture conditions, determine its nutritional composition, extract polyunsaturated fatty acids (PUFAs) [...] Read more.
Aurantiochytrium is a heterotrophic marine microalga that has potential industrial applications. The main objectives of this study were to isolate an Aurantiochytrium strain from Sand Cay (Son Ca) Island, Vietnam, optimize its culture conditions, determine its nutritional composition, extract polyunsaturated fatty acids (PUFAs) in the free (FFA) and the alkyl ester (FAAE) forms, and evaluate the antioxidation and neuroprotection properties of the PUFAs. Aurantiochytrium sp. SC145 can be grown stably under laboratory conditions. Its culture conditions were optimized for a dry cell weight (DCW) of 31.18 g/L, with total lipids comprising 25.29%, proteins 7.93%, carbohydrates 15.21%, and carotenoid at 143.67 µg/L of DCW. The FAAEs and FFAs extracted from Aurantiochytrium sp. SC145 were rich in omega 3–6–9 fatty acids (40.73% and 44.00% of total fatty acids, respectively). No acute or subchronic oral toxicity was determined in mice fed with the PUFAs in FFA or FAAE forms at different doses over 90 days. Furthermore, the PUFAs in the FFA or FAAE forms and their main constituents of EPA, DHA, and ALA showed antioxidant and AChE inhibitory properties and neuroprotective activities against damage caused by H2O2- and amyloid-ß protein fragment 25–35 (Aβ25-35)-induced C6 cells. These data suggest that PUFAs extracted from Aurantiochytrium sp. SC145 may be a potential therapeutic target for the treatment of neurodegenerative disorders. Full article
(This article belongs to the Special Issue Marine Thraustochytrids: Biology and Biotechnology)
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14 pages, 4610 KiB  
Article
Dieckol Isolated from Eisenia bicyclis Ameliorates Wrinkling and Improves Skin Hydration via MAPK/AP-1 and TGF-β/Smad Signaling Pathways in UVB-Irradiated Hairless Mice
by Jae-Min Kim, Kyung-Sook Chung, Young-Seo Yoon, Seo-Yun Jang, So-Won Heo, Geonha Park, Young-Pyo Jang, Hye-Shin Ahn, Yu-Kyong Shin, Sun-Hee Lee and Kyung-Tae Lee
Mar. Drugs 2022, 20(12), 779; https://doi.org/10.3390/md20120779 - 14 Dec 2022
Cited by 11 | Viewed by 2400
Abstract
Repetitive exposure to ultraviolet B (UVB) is one of the main causes of skin photoaging. We previously reported that dieckol isolated from Eisenia bicyclis extract has potential anti-photoaging effects in UVB-irradiated Hs68 cells. Here, we aimed to evaluate the anti-photoaging activity of dieckol [...] Read more.
Repetitive exposure to ultraviolet B (UVB) is one of the main causes of skin photoaging. We previously reported that dieckol isolated from Eisenia bicyclis extract has potential anti-photoaging effects in UVB-irradiated Hs68 cells. Here, we aimed to evaluate the anti-photoaging activity of dieckol in a UVB-irradiated hairless mouse model. In this study, hairless mice were exposed to UVB for eight weeks. At the same time, dieckol at two doses (5 or 10 mg/kg) was administered orally three times a week. We found that dieckol suppressed UVB-induced collagen degradation and matrix metalloproteinases (MMPs)-1, -3, and -9 expression by regulating transforming growth factor beta (TGF-β)/Smad2/3 and mitogen-activated protein kinases (MAPKs)/activator protein-1 (AP-1) signaling. In addition, dieckol rescued the production of hyaluronic acid (HA) and effectively restored the mRNA expression of hyaluronan synthase (HAS)-1/-2 and hyaluronidase (HYAL)-1/-2 in UVB-irradiated hairless mice. We observed a significant reduction in transepidermal water loss (TEWL), epidermal/dermal thickness, and wrinkle formation in hairless mice administered dieckol. Based on these results, we suggest that dieckol, due to its anti-photoaging role, may be used as a nutricosmetic ingredient for improving skin health. Full article
(This article belongs to the Special Issue Pharmaceutical, Nutraceutical, Cosmeceutical and Biotechnological Potentials of Southeast Asian Marine Resources)
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13 pages, 3071 KiB  
Article
New Dibenzo-α-pyrone Derivatives with α-Glucosidase Inhibitory Activities from the Marine-Derived Fungus Alternaria alternata
by Jinxin Zhang, Baodan Zhang, Lei Cai and Ling Liu
Mar. Drugs 2022, 20(12), 778; https://doi.org/10.3390/md20120778 - 14 Dec 2022
Cited by 10 | Viewed by 2492
Abstract
Three new dibenzo-α-pyrone derivatives, alternolides A–C (1–3), and seven known congeners (4–10) were isolated from the marine-derived fungus of Alternaria alternata LW37 assisted by the one strain-many compounds (OSMAC) strategy. The structures of [...] Read more.
Three new dibenzo-α-pyrone derivatives, alternolides A–C (1–3), and seven known congeners (4–10) were isolated from the marine-derived fungus of Alternaria alternata LW37 assisted by the one strain-many compounds (OSMAC) strategy. The structures of 1–3 were established by extensive spectroscopic analyses, and their absolute configurations were determined by modified Snatzke′s method and electronic circular dichroism (ECD) calculations. Compounds 6 and 7 showed good 1,1-diphenyl-2-picrylhydrazyl (DPPH) antioxidant scavenging activities with IC50 values of 83.94 ± 4.14 and 23.60 ± 1.23 µM, respectively. Additionally, 2, 3 and 7 exhibited inhibitory effects against α-glucosidase with IC50 values of 725.85 ± 4.75, 451.25 ± 6.95 and 6.27 ± 0.68 µM, respectively. The enzyme kinetics study indicated 2 and 3 were mixed-type inhibitors of α-glucosidase with Ki values of 347.0 and 108.5 µM, respectively. Furthermore, the interactions of 2, 3 and 7 with α-glucosidase were investigated by molecular docking. Full article
(This article belongs to the Section Structural Studies on Marine Natural Products)
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12 pages, 3368 KiB  
Article
A Molecular Modeling Investigation of the Therapeutic Potential of Marine Compounds as DPP-4 Inhibitors
by Priya Antony, Bincy Baby, Hamda Mohammed Aleissaee and Ranjit Vijayan
Mar. Drugs 2022, 20(12), 777; https://doi.org/10.3390/md20120777 - 13 Dec 2022
Cited by 5 | Viewed by 2144
Abstract
Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by elevated levels of blood glucose due to insulin resistance or insulin-secretion defects. The development of diabetes is mainly attributed to the interaction of several complex pathogenic, genetic, environmental and metabolic processes. [...] Read more.
Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by elevated levels of blood glucose due to insulin resistance or insulin-secretion defects. The development of diabetes is mainly attributed to the interaction of several complex pathogenic, genetic, environmental and metabolic processes. Dipeptidyl peptidase-4 (DPP-4) is a serine protease that cleaves X-proline dipeptides from the N-terminus of several polypeptides, including natural hypoglycemic incretin hormones. Inhibition of this enzyme restores and maintains glucose homeostasis, making it an attractive drug target for the management of T2DM. Natural products are important sources of bioactive agents for anti-T2DM drug discovery. Marine ecosystems are a rich source of bioactive products and have inspired the development of drugs for various human disorders, including diabetes. Here, structure-based virtual screening and molecular docking were performed to identify antidiabetic compounds from the Comprehensive Marine Natural Products Database (CMNPD). The binding characteristics of two shortlisted compounds, CMNPD13046 and CMNPD17868, were assessed using molecular dynamics simulations. Thus, this study provides insights into the potential antidiabetic activity and the underlying molecular mechanism of two compounds of marine origin. These compounds could be investigated further for the development of potent DPP-4 inhibitors. Full article
(This article belongs to the Special Issue Women in Science: Their Contribution in Marine Drugs)
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13 pages, 5803 KiB  
Article
Anticancer Activity of Mannose-Specific Lectin, BPL2, from Marine Green Alga Bryopsis plumosa
by Jei Ha Lee, Set Byul Lee, Heabin Kim, Jae Min Shin, Moongeun Yoon, Hye Suck An and Jong Won Han
Mar. Drugs 2022, 20(12), 776; https://doi.org/10.3390/md20120776 - 13 Dec 2022
Cited by 9 | Viewed by 2585
Abstract
Lectin is a carbohydrate-binding protein that recognizes specific cells by binding to cell-surface polysaccharides. Tumor cells generally show various glycosylation patterns, making them distinguishable from non-cancerous cells. Consequently, lectin has been suggested as a good anticancer agent. Herein, the anticancer activity of Bryopsis [...] Read more.
Lectin is a carbohydrate-binding protein that recognizes specific cells by binding to cell-surface polysaccharides. Tumor cells generally show various glycosylation patterns, making them distinguishable from non-cancerous cells. Consequently, lectin has been suggested as a good anticancer agent. Herein, the anticancer activity of Bryopsis plumosa lectins (BPL1, BPL2, and BPL3) was screened and tested against lung cancer cell lines (A549, H460, and H1299). BPL2 showed high anticancer activity compared to BPL1 and BPL3. Cell viability was dependent on BPL2 concentration and incubation time. The IC50 value for lung cancer cells was 50 μg/mL after 24 h of incubation in BPL2 containing medium; however, BPL2 (50 μg/mL) showed weak toxicity in non-cancerous cells (MRC5). BPL2 affected cancer cell growth while non-cancerous cells were less affected. Further, BPL2 (20 μg/mL) inhibited cancer cell invasion and migration (rates were ˂20%). BPL2 induced the downregulation of epithelial-to-mesenchymal transition-related genes (Zeb1, vimentin, and Twist). Co-treatment with BPL2 and gefitinib (10 μg/mL and 10 μM, respectively) showed a synergistic effect compared with monotherapy. BPL2 or gefitinib monotherapy resulted in approximately 90% and 70% cell viability, respectively, with concomitant treatment showing 40% cell viability. Overall, BPL2 can be considered a good candidate for development into an anticancer agent. Full article
(This article belongs to the Topic Antitumor Activity of Natural Products and Related Compounds)
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21 pages, 1339 KiB  
Article
Brown Macroalgae (Phaeophyceae): A Valuable Reservoir of Antimicrobial Compounds on Northern Coast of Spain
by Susana Rubiño, César Peteiro, Teresa Aymerich and Maria Hortós
Mar. Drugs 2022, 20(12), 775; https://doi.org/10.3390/md20120775 - 12 Dec 2022
Cited by 11 | Viewed by 3242
Abstract
The search for new sources of antimicrobial compounds has become an urgent need, due to the threat that the spread of bacterial resistance represents for global health and food safety. Brown macroalgae have been proposed as a great reservoir in the search for [...] Read more.
The search for new sources of antimicrobial compounds has become an urgent need, due to the threat that the spread of bacterial resistance represents for global health and food safety. Brown macroalgae have been proposed as a great reservoir in the search for novel antimicrobial compounds. In this study, mid-polarity extracts were performed with a selection of 20 brown macroalgae species from northern Spain. The total polyphenol, carbohydrate and protein contents were quantified by spectrophotometry. The volatile organic compounds (VOCs) of whole macroalgae were also studied as a biomarker of their metabolic state in the representative species of the tested families by gas chromatography-mass spectrometry (GC-MS). The antimicrobial potential of the extracts was assessed by a disk diffusion assay against 20 target bacteria and further determinations of the minimum inhibitory (MIC) and minimum bactericidal concentrations (MBC) were performed by a microdilution assay for the active extracts. Ericaria selaginoides, Bifurcaria bifurcata and Dictyota dichotoma showed an antimicrobial effect against six Gram-positive strains: Bacillus cereus, Bacillus subtilis, Geobacillus stearothermophilus, Listeria monocytogenes, Staphylococcus aureus and Staphylococcus haemolyticus. The phenolic content was generally higher in the extracts that showed antimicrobial activity, followed by carbohydrates and low contents of proteins. The results obtained in this study reveal the potential of brown macroalgae as a promising alternative source of antimicrobial compounds as functional ingredients for the application in industrial fields. Full article
(This article belongs to the Special Issue Researches in High-Value Algal Products: From Extraction to Application)
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13 pages, 1201 KiB  
Review
Marine Polyphenol Phlorotannins as a Natural Sleep Aid for Treatment of Insomnia: A Review of Sedative–Hypnotic Effects and Mechanism of Action
by Seonghui Kim, Duhyeon Kim, Min Young Um, Minseok Yoon, Jae-Suk Choi, Yung Hyun Choi and Suengmok Cho
Mar. Drugs 2022, 20(12), 774; https://doi.org/10.3390/md20120774 - 10 Dec 2022
Cited by 4 | Viewed by 3236
Abstract
Insomnia is a common sleep disorder. Natural sleep aids are gaining worldwide popularity as alternatives to prescription drugs for improving sleep. Recently, numerous studies have investigated the sedative–hypnotic effects of the polyphenols of terrestrial plants. The hypnotic effects of marine polyphenols have also [...] Read more.
Insomnia is a common sleep disorder. Natural sleep aids are gaining worldwide popularity as alternatives to prescription drugs for improving sleep. Recently, numerous studies have investigated the sedative–hypnotic effects of the polyphenols of terrestrial plants. The hypnotic effects of marine polyphenols have also been studied in recent years. Phlorotannins are marine polyphenols that are found only in brown algae. Phlorotannins exert sedative–hypnotic effects via the gamma-aminobutyric acid type A-benzodiazepine receptor. In addition, the brown seaweed Ecklonia cava supplement containing phlorotannins has been approved by the Ministry of Food and Drug Safety as a health-functional ingredient that helps improve sleep quality. Currently, it is meaningful to deal with the sedative–hypnotic effects of phlorotannins as natural sleep aids. The current review comprehensively presents the sedative–hypnotic effects in animal models and human clinical trials as well as their mechanism of action, extraction, purification, and safety. Full article
(This article belongs to the Special Issue The Mechanisms of Action of Bioactive Marine Natural Products)
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17 pages, 2430 KiB  
Review
Conus regius-Derived Conotoxins: Novel Therapeutic Opportunities from a Marine Organism
by Francesco Margiotta, Laura Micheli, Clara Ciampi, Carla Ghelardini, J. Michael McIntosh and Lorenzo Di Cesare Mannelli
Mar. Drugs 2022, 20(12), 773; https://doi.org/10.3390/md20120773 - 10 Dec 2022
Cited by 6 | Viewed by 2851
Abstract
Conus regius is a marine venomous mollusk of the Conus genus that captures its prey by injecting a rich cocktail of bioactive disulfide bond rich peptides called conotoxins. These peptides selectively target a broad range of ion channels, membrane receptors, transporters, and enzymes, [...] Read more.
Conus regius is a marine venomous mollusk of the Conus genus that captures its prey by injecting a rich cocktail of bioactive disulfide bond rich peptides called conotoxins. These peptides selectively target a broad range of ion channels, membrane receptors, transporters, and enzymes, making them valuable pharmacological tools and potential drug leads. C. regius-derived conotoxins are particularly attractive due to their marked potency and selectivity against specific nicotinic acetylcholine receptor subtypes, whose signalling is involved in pain, cognitive disorders, drug addiction, and cancer. However, the species-specific differences in sensitivity and the low stability and bioavailability of these conotoxins limit their clinical development as novel therapeutic agents for these disorders. Here, we give an overview of the main pharmacological features of the C. regius-derived conotoxins described so far, focusing on the molecular mechanisms underlying their potential therapeutic effects. Additionally, we describe adoptable chemical engineering solutions to improve their pharmacological properties for future potential clinical translation. Full article
(This article belongs to the Special Issue Conotoxin and Conotoxin Analogues: A Pharmacy Cabinet under the Sea)
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26 pages, 4098 KiB  
Review
Biological Properties and Health-Promoting Functions of Laminarin: A Comprehensive Review of Preclinical and Clinical Studies
by Shanmugapriya Karuppusamy, Gaurav Rajauria, Stephen Fitzpatrick, Henry Lyons, Helena McMahon, James Curtin, Brijesh K. Tiwari and Colm O’Donnell
Mar. Drugs 2022, 20(12), 772; https://doi.org/10.3390/md20120772 - 10 Dec 2022
Cited by 34 | Viewed by 5339
Abstract
Marine algal species comprise of a large portion of polysaccharides which have shown multifunctional properties and health benefits for treating and preventing human diseases. Laminarin, or β-glucan, a storage polysaccharide from brown algae, has been reported to have potential pharmacological properties such as [...] Read more.
Marine algal species comprise of a large portion of polysaccharides which have shown multifunctional properties and health benefits for treating and preventing human diseases. Laminarin, or β-glucan, a storage polysaccharide from brown algae, has been reported to have potential pharmacological properties such as antioxidant, anti-tumor, anti-coagulant, anticancer, immunomodulatory, anti-obesity, anti-diabetic, anti-inflammatory, wound healing, and neuroprotective potential. It has been widely investigated as a functional material in biomedical applications as it is biodegradable, biocompatible, and is low toxic substances. The reported preclinical and clinical studies demonstrate the potential of laminarin as natural alternative agents in biomedical and industrial applications such as nutraceuticals, pharmaceuticals, functional food, drug development/delivery, and cosmeceuticals. This review summarizes the biological activities of laminarin, including mechanisms of action, impacts on human health, and reported health benefits. Additionally, this review also provides an overview of recent advances and identifies gaps and opportunities for further research in this field. It further emphasizes the molecular characteristics and biological activities of laminarin in both preclinical and clinical settings for the prevention of the diseases and as potential therapeutic interventions. Full article
(This article belongs to the Special Issue Marine Bioactive Compounds against Oxidative Stress and Inflammation)
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32 pages, 4512 KiB  
Review
Fungal Bergamotane Sesquiterpenoids—Potential Metabolites: Sources, Bioactivities, and Biosynthesis
by Maan T. Khayat, Khadijah A. Mohammad, Abdelsattar M. Omar, Gamal A. Mohamed and Sabrin R. M. Ibrahim
Mar. Drugs 2022, 20(12), 771; https://doi.org/10.3390/md20120771 - 8 Dec 2022
Cited by 4 | Viewed by 1866
Abstract
The marine environment represents the largest ecosystem on the Earth’s surface. Marine-derived fungi are of remarkable importance as they are a promising pool of diverse classes of bioactive metabolites. Bergamotane sesquiterpenoids are an uncommon class of terpenoids. They possess diverse biological properties, such [...] Read more.
The marine environment represents the largest ecosystem on the Earth’s surface. Marine-derived fungi are of remarkable importance as they are a promising pool of diverse classes of bioactive metabolites. Bergamotane sesquiterpenoids are an uncommon class of terpenoids. They possess diverse biological properties, such as plant growth regulation, phototoxic, antimicrobial, anti-HIV, cytotoxic, pancreatic lipase inhibition, antidiabetic, anti-inflammatory, and immunosuppressive traits. The current work compiles the reported bergamotane sesquiterpenoids from fungal sources in the period ranging from 1958 to June 2022. A total of 97 compounds from various fungal species were included. Among these metabolites, 38 compounds were derived from fungi isolated from different marine sources. Furthermore, the biological activities, structural characterization, and biosynthesis of the compounds are also discussed. The summary in this work provides a detailed overview of the reported knowledge of fungal bergamotane sesquiterpenoids. Moreover, this in-depth and complete review could provide new insights for developing and discovering new valuable pharmaceutical agents from these natural metabolites. Full article
(This article belongs to the Special Issue Diversity of Marine Fungi as a Source of Bioactive Natural Products)
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17 pages, 4162 KiB  
Article
The Anti-Photoaging Activity of Peptides from Pinctada martensii Meat
by Mengfen Wei, Huamai Qiu, Jie Zhou, Chenghao Yang, Yifan Chen and Lijun You
Mar. Drugs 2022, 20(12), 770; https://doi.org/10.3390/md20120770 - 8 Dec 2022
Cited by 13 | Viewed by 2456
Abstract
Long-term exposure to ultraviolet-B (UVB) can cause photoaging. Peptides from Pinctada martensii meat have been shown to have anti-photoaging activities, but their mechanism of action is rarely studied. In this study, Pinctada martensii meat hydrolysates (PME) were prepared by digestive enzymes and then [...] Read more.
Long-term exposure to ultraviolet-B (UVB) can cause photoaging. Peptides from Pinctada martensii meat have been shown to have anti-photoaging activities, but their mechanism of action is rarely studied. In this study, Pinctada martensii meat hydrolysates (PME) were prepared by digestive enzymes and then separated by ultrafiltration and Sephadex G-25 gel filtration chromatography to obtain a purified fraction (G2). The fraction G2 was identified by ultra-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS), and peptide sequences were synthesized by solid-phase synthesis. The mechanism of anti-photoaging activities was investigated using a human immortalised epidermal (HaCaT) cell model. Results showed that peptides from Pinctada martensii meat increased UVB-induced cell viability and reduced the contents of interstitial collagenase (MMP-1) and matrix lysing enzyme (MMP-3) in HaCaT cells. Furthermore, the fraction of G2 significantly downregulated the expression of p38, EKR, JNK, MMP-1, and MMP-3 in HaCaT cells. The peptide sequences Phe-His (FH), Ala-Leu (AL), Met-Tyr (MY), Ala-Gly-Phe (AGF), and Ile-Tyr-Pro (IYP) were identified and synthesized. Besides, FH reduced the contents of MMP-1 and MMP-3 in HaCaT cells, combining them effectively in molecular docking analysis. Thus, peptides from Pinctada martensii meat showed anti-photoaging activities and might have the potential to be used as an anti-photoaging agent in functional foods. Full article
(This article belongs to the Special Issue Photoprotective Compounds from Marine Organisms)
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23 pages, 4014 KiB  
Article
Exploring Micromonospora as Phocoenamicins Producers
by Maria Kokkini, Cristina González Heredia, Daniel Oves-Costales, Mercedes de la Cruz, Pilar Sánchez, Jesús Martín, Francisca Vicente, Olga Genilloud and Fernando Reyes
Mar. Drugs 2022, 20(12), 769; https://doi.org/10.3390/md20120769 - 7 Dec 2022
Cited by 4 | Viewed by 2474
Abstract
Over the past few years, new technological and scientific advances have reinforced the field of natural product discovery. The spirotetronate class of natural products has recently grown with the discovery of phocoenamicins, natural actinomycete derived compounds that possess different antibiotic activities. Exploring the [...] Read more.
Over the past few years, new technological and scientific advances have reinforced the field of natural product discovery. The spirotetronate class of natural products has recently grown with the discovery of phocoenamicins, natural actinomycete derived compounds that possess different antibiotic activities. Exploring the MEDINA’s strain collection, 27 actinomycete strains, including three marine-derived and 24 terrestrial strains, were identified as possible phocoenamicins producers and their taxonomic identification by 16S rDNA sequencing showed that they all belong to the Micromonospora genus. Using an OSMAC approach, all the strains were cultivated in 10 different media each, resulting in 270 fermentations, whose extracts were analyzed by LC-HRMS and subjected to High-throughput screening (HTS) against methicillin-resistant Staphylococcus aureus (MRSA), Mycobacterium tuberculosis H37Ra and Mycobacterium bovis. The combination of LC-UV-HRMS analyses, metabolomics analysis and molecular networking (GNPS) revealed that they produce several related spirotetronates not disclosed before. Variations in the culture media were identified as the most determining factor for phocoenamicin production and the best producer strains and media were established. Herein, we reported the chemically diverse production and metabolic profiling of Micromonospora sp. strains, including the known phocoenamicins and maklamicin, reported for the first time as being related to this family of compounds, as well as the bioactivity of their crude extracts. Although our findings do not confirm previous statements about phocoenamicins production only in unique marine environments, they have identified marine-derived Micromonospora species as the best producers of phocoenamicins in terms of both the abundance in their extracts of some major members of the structural class and the variety of molecular structures produced. Full article
(This article belongs to the Special Issue Marine Drugs Research in Spain)
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31 pages, 6348 KiB  
Review
Anti-Infective Secondary Metabolites of the Marine Cyanobacterium Lyngbya Morphotype between 1979 and 2022
by Diaa T. A. Youssef, Shatha J. Mufti, Abeer A. Badiab and Lamiaa A. Shaala
Mar. Drugs 2022, 20(12), 768; https://doi.org/10.3390/md20120768 - 7 Dec 2022
Cited by 5 | Viewed by 2693
Abstract
Cyanobacteria ascribed to the genus Lyngbya (Family Oscillatoriaceae) represent a potential therapeutic gold mine of chemically and biologically diverse natural products that exhibit a wide array of biological properties. Phylogenetic analyses have established the Lyngbya ‘morpho-type’ as a highly polyphyletic group and have [...] Read more.
Cyanobacteria ascribed to the genus Lyngbya (Family Oscillatoriaceae) represent a potential therapeutic gold mine of chemically and biologically diverse natural products that exhibit a wide array of biological properties. Phylogenetic analyses have established the Lyngbya ‘morpho-type’ as a highly polyphyletic group and have resulted in taxonomic revision and description of an additional six new cyanobacterial genera in the same family to date. Among the most prolific marine cyanobacterial producers of biologically active compounds are the species Moorena producens (previously L. majuscula, then Moorea producens), M. bouillonii (previously L. bouillonii), and L. confervoides. Over the years, compounding evidence from in vitro and in vivo studies in support of the significant pharmaceutical potential of ‘Lyngbya’-derived natural products has made the Lyngbya morphotype a significant target for biomedical research and novel drug leads development. This comprehensive review covers compounds with reported anti-infective activities through 2022 from the Lyngbya morphotype, including new genera arising from recent phylogenetic re-classification. So far, 72 anti-infective secondary metabolites have been isolated from various Dapis, Lyngbya, Moorea, and Okeania species. These compounds showed significant antibacterial, antiparasitic, antifungal, antiviral and molluscicidal effects. Herein, a comprehensive literature review covering the natural source, chemical structure, and biological/pharmacological properties will be presented. Full article
(This article belongs to the Section Marine Chemoecology for Drug Discovery)
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21 pages, 3477 KiB  
Article
Enhancing Bioproducts in Seaweeds via Sustainable Aquaculture: Antioxidant and Sun-Protection Compounds
by Doron Yehoshua Ashkenazi, Félix L. Figueroa, Nathalie Korbee, Marta García-Sánchez, Julia Vega, Shoshana Ben-Valid, Guy Paz, Eitan Salomon, Álvaro Israel and Avigdor Abelson
Mar. Drugs 2022, 20(12), 767; https://doi.org/10.3390/md20120767 - 7 Dec 2022
Cited by 8 | Viewed by 10723
Abstract
Marine macroalgae are considered an untapped source of healthy natural metabolites and their market demand is rapidly increasing. Intertidal macroalgae present chemical defense mechanisms that enable them to thrive under changing environmental conditions. These intracellular chemicals include compounds that can be used for [...] Read more.
Marine macroalgae are considered an untapped source of healthy natural metabolites and their market demand is rapidly increasing. Intertidal macroalgae present chemical defense mechanisms that enable them to thrive under changing environmental conditions. These intracellular chemicals include compounds that can be used for human benefit. The aim of this study was to test cultivation protocols that direct seaweed metabolic responses to enhance the production of target antioxidant and photoprotective biomaterials. We present an original integrated multi-trophic aquaculture (IMTA) design, based on a two-phase cultivation plan, in which three seaweed species were initially fed by fish effluents, and subsequently exposed to various abiotic stresses, namely, high irradiance, nutrient starvation, and high salinity. The combined effect of the IMTA’s high nutrient concentrations and/or followed by the abiotic stressors enhanced the seaweeds’ content of mycosporine-like amino acids (MAAs) by 2.3-fold, phenolic compounds by 1.4-fold, and their antioxidant capacity by 1.8-fold. The Sun Protection Factor (SPF) rose by 2.7-fold, and the chlorophyll and phycobiliprotein synthesis was stimulated dramatically by an order of magnitude. Our integrated cultivation system design offers a sustainable approach, with the potential to be adopted by emerging industries for food and health applications. Full article
(This article belongs to the Special Issue High-Value Products from Seaweeds: Medical, Cosmetic, and Biotechnological Applications)
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15 pages, 2799 KiB  
Article
Eckmaxol Isolated from Ecklonia maxima Attenuates Particulate-Matter-Induced Inflammation in MH-S Lung Macrophage
by D. P. Nagahawatta, N. M. Liyanage, H. H. A. C. K. Jayawardhana, Thilina U. Jayawardena, Hyo-Geun Lee, Moon-Soo Heo and You-Jin Jeon
Mar. Drugs 2022, 20(12), 766; https://doi.org/10.3390/md20120766 - 7 Dec 2022
Cited by 6 | Viewed by 2358
Abstract
Airborne particulate matter (PM) originating from industrial processes is a major threat to the environment and health in East Asia. PM can cause asthma, collateral lung tissue damage, oxidative stress, allergic reactions, and inflammation. The present study was conducted to evaluate the protective [...] Read more.
Airborne particulate matter (PM) originating from industrial processes is a major threat to the environment and health in East Asia. PM can cause asthma, collateral lung tissue damage, oxidative stress, allergic reactions, and inflammation. The present study was conducted to evaluate the protective effect of eckmaxol, a phlorotannin isolated from Ecklonia maxima, against PM-induced inflammation in MH-S macrophage cells. It was found that PM induced inflammation in MH-S lung macrophages, which was inhibited by eckmaxol treatment in a dose-dependent manner (21.0–84.12 µM). Eckmaxol attenuated the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in PM-induced lung macrophages. Subsequently, nitric oxide (NO), prostaglandin E-2 (PGE-2), and pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) were downregulated. PM stimulated inflammation in MH-S lung macrophages by activating Toll-like receptors (TLRs), nuclear factor-kappa B (NF-κB), and mitogen-activated protein kinase (MAPK) pathways. Eckmaxol exhibited anti-inflammatory properties by suppressing the activation of TLRs, downstream signaling of NF-κB (p50 and p65), and MAPK pathways, including c-Jun N-terminal kinase (JNK) and p38. These findings suggest that eckmaxol may offer substantial therapeutic potential in the treatment of inflammatory diseases. Full article
(This article belongs to the Special Issue Marine Bioactive Compounds against Oxidative Stress and Inflammation)
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18 pages, 4272 KiB  
Review
Sulfur-Containing Metabolites from Marine and Terrestrial Fungal Sources: Origin, Structures, and Bioactivities
by Zhaoming Liu, Mingqiong Li, Shuo Wang, Huibin Huang and Weimin Zhang
Mar. Drugs 2022, 20(12), 765; https://doi.org/10.3390/md20120765 - 7 Dec 2022
Cited by 9 | Viewed by 2391
Abstract
Organosulfur natural products (NPs) refer to the different kinds of small molecular-containing sulfur (S) elements. Sulfur-containing NPs tightly link to the biochemical processes and play an important role in the pharmaceutical industry. The majority of S-containing NPs are generally isolated from Alliaceae plants [...] Read more.
Organosulfur natural products (NPs) refer to the different kinds of small molecular-containing sulfur (S) elements. Sulfur-containing NPs tightly link to the biochemical processes and play an important role in the pharmaceutical industry. The majority of S-containing NPs are generally isolated from Alliaceae plants or bacteria, and those from fungi are still relatively rare. In recent years, an increasing number of S-containing metabolites have been discovered in marine and terrestrial fungi, but there is no comprehensive and targeted review to summarize the studies. In order to make it more straightforward to better grasp the fungal-derived S-containing NPs and understand the particularity of marine S-containing NPs compared to those from terrestrial fungi, we summarized the chemical structures and biological activities of 89 new fungal-derived S-containing metabolites from 1929 when the penicillin was discovered to the present in this current review. The structural and bioactive diversity of these S-containing metabolites were concluded in detail, and the preliminary mechanism for C-S bond formation in fungi was also discussed briefly. Full article
(This article belongs to the Section Structural Studies on Marine Natural Products)
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11 pages, 6884 KiB  
Article
Polysaccharide from Edible Alga Enteromorpha clathrata Improves Ulcerative Colitis in Association with Increased Abundance of Parabacteroides spp. in the Gut Microbiota of Dextran Sulfate Sodium-Fed Mice
by Mingfeng Ma, Tianyu Fu, Yamin Wang, Aijun Zhang, Puyue Gao, Qingsen Shang and Guangli Yu
Mar. Drugs 2022, 20(12), 764; https://doi.org/10.3390/md20120764 - 4 Dec 2022
Cited by 9 | Viewed by 2499
Abstract
Polysaccharide from the edible alga Enteromorpha clathrata has been demonstrated to exert beneficial effects on human health. However, what effect it has on inflammatory bowel diseases has not been investigated. Here, using a mouse model of dextran sulfate sodium (DSS)-induced ulcerative colitis, we [...] Read more.
Polysaccharide from the edible alga Enteromorpha clathrata has been demonstrated to exert beneficial effects on human health. However, what effect it has on inflammatory bowel diseases has not been investigated. Here, using a mouse model of dextran sulfate sodium (DSS)-induced ulcerative colitis, we illustrate that Enteromorpha clathrata polysaccharide (ECP) could alleviate body weight loss, reduce incidences of colonic bleeding, improve stool consistency and ameliorate mucosal damage in diseased mice. 16S rRNA high-throughput sequencing and bioinformatic analysis indicated that ECP significantly changed the structure of the gut microbiota and increased the abundance of Parabacteroides spp. in DSS-fed mice. In vitro fermentation studies further confirmed that ECP could promote the growth of Parabacteroides distasonis F1-28, a next-generation probiotic bacterium isolated from the human gut, and increase its production of short-chain fatty acids. Additionally, Parabacteroides distasonis F1-28 was also found to have anti-ulcerative colitis effects in DSS-fed mice. Altogether, our study demonstrates for the first time a beneficial effect of ECP on ulcerative colitis and provides a possible basis for understanding its therapeutic mechanisms from the perspective of symbiotic gut bacteria Parabacteroides distasonis. Full article
(This article belongs to the Collection Marine Polysaccharides)
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51 pages, 7612 KiB  
Article
Polypharmacological Cell-Penetrating Peptides from Venomous Marine Animals Based on Immunomodulating, Antimicrobial, and Anticancer Properties
by Shiva Hemmati and Haniyeh Rasekhi Kazerooni
Mar. Drugs 2022, 20(12), 763; https://doi.org/10.3390/md20120763 - 4 Dec 2022
Cited by 12 | Viewed by 3535
Abstract
Complex pathological diseases, such as cancer, infection, and Alzheimer’s, need to be targeted by multipronged curative. Various omics technologies, with a high rate of data generation, demand artificial intelligence to translate these data into druggable targets. In this study, 82 marine venomous animal [...] Read more.
Complex pathological diseases, such as cancer, infection, and Alzheimer’s, need to be targeted by multipronged curative. Various omics technologies, with a high rate of data generation, demand artificial intelligence to translate these data into druggable targets. In this study, 82 marine venomous animal species were retrieved, and 3505 cryptic cell-penetrating peptides (CPPs) were identified in their toxins. A total of 279 safe peptides were further analyzed for antimicrobial, anticancer, and immunomodulatory characteristics. Protease-resistant CPPs with endosomal-escape ability in Hydrophis hardwickii, nuclear-localizing peptides in Scorpaena plumieri, and mitochondrial-targeting peptides from Synanceia horrida were suitable for compartmental drug delivery. A broad-spectrum S. horrida-derived antimicrobial peptide with a high binding-affinity to bacterial membranes was an antigen-presenting cell (APC) stimulator that primes cytokine release and naïve T-cell maturation simultaneously. While antibiofilm and wound-healing peptides were detected in Synanceia verrucosa, APC epitopes as universal adjuvants for antiviral vaccination were in Pterois volitans and Conus monile. Conus pennaceus-derived anticancer peptides showed antiangiogenic and IL-2-inducing properties with moderate BBB-permeation and were defined to be a tumor-homing peptide (THP) with the ability to inhibit programmed death ligand-1 (PDL-1). Isoforms of RGD-containing peptides with innate antiangiogenic characteristics were in Conus tessulatus for tumor targeting. Inhibitors of neuropilin-1 in C. pennaceus are proposed for imaging probes or therapeutic delivery. A Conus betulinus cryptic peptide, with BBB-permeation, mitochondrial-targeting, and antioxidant capacity, was a stimulator of anti-inflammatory cytokines and non-inducer of proinflammation proposed for Alzheimer’s. Conclusively, we have considered the dynamic interaction of cells, their microenvironment, and proportional-orchestrating-host- immune pathways by multi-target-directed CPPs resembling single-molecule polypharmacology. This strategy might fill the therapeutic gap in complex resistant disorders and increase the candidates’ clinical-translation chance. Full article
(This article belongs to the Special Issue Marine Bioactive Peptides: Structure, Function, and Therapeutic Potential - III)
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19 pages, 4407 KiB  
Article
Xestospongia muta Fraction-7 and Linoleic Acid: Effects on SR-BI Gene Expression and HDL Cholesterol Uptake
by Nurul Adila Azemi, Ahmad Khusairi Azemi, Luqman Abu-Bakar, Vigneswari Sevakumaran, Tengku Sifzizul Tengku Muhammad and Noraznawati Ismail
Mar. Drugs 2022, 20(12), 762; https://doi.org/10.3390/md20120762 - 4 Dec 2022
Cited by 3 | Viewed by 1964
Abstract
Xestospongia muta is a marine sponge belonging to the family Petrosiidae. It is an important source of biologically active marine natural products, with different kinds of essential fatty acids. Scavenger receptor class B type I (SR-BI) is the main receptor for [...] Read more.
Xestospongia muta is a marine sponge belonging to the family Petrosiidae. It is an important source of biologically active marine natural products, with different kinds of essential fatty acids. Scavenger receptor class B type I (SR-BI) is the main receptor for high-density lipoprotein (HDL) cholesterol, which plays a pivotal role in preventing atherosclerosis. It removes cholesterol from HDL cholesterol, returning lipid-poor lipoprotein into blood circulation. The present study investigated the effects of X. muta Fraction-7 and linoleic acid on SR-BI gene expression and HDL cholesterol uptake. In vitro studies of the activity of X. muta and linoleic acid against the therapeutic target for hypercholesterolemia were conducted using the HDL receptor SR-BI via luciferase assay and HepG2 cells. In the present study, Fraction-7 of X. muta showed the highest expression level of the SR-BI gene via luciferase assay. Profiling of Fraction-7 of X. muta by GC-MS revealed 58 compounds, comprising various fatty acids, particularly linoleic acid. The in vitro study in HepG2 cells showed that the Fraction-7 of X. muta and linoleic acid (an active compound in X. muta) increased SR-BI mRNA expression by 129% and 85%, respectively, compared to the negative control. Linoleic acid increased HDL uptake by 3.21-fold compared to the negative control. Thus, the Fraction-7 of X. muta and linoleic acid have the potential to be explored as adjuncts in the treatment of hypercholesterolemia to prevent or reduce the severity of atherosclerosis development. Full article
(This article belongs to the Special Issue Marine Drugs in Cell Signaling Pathways)
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24 pages, 970 KiB  
Article
Cosmetic Application of Cyanobacteria Extracts with a Sustainable Vision to Skincare: Role in the Antioxidant and Antiaging Process
by Janaína Morone, Graciliana Lopes, João Morais, Jorge Neves, Vítor Vasconcelos and Rosário Martins
Mar. Drugs 2022, 20(12), 761; https://doi.org/10.3390/md20120761 - 2 Dec 2022
Cited by 10 | Viewed by 4273
Abstract
Nature-based and sustainably sourced cosmetics have been dominating the area of skincare products worldwide. Due to their antioxidant and antiaging properties, compounds from cyanobacteria, such as carotenoids and phycobiliproteins, may replace synthetic ingredients in cosmetic formulations and may be used in products such [...] Read more.
Nature-based and sustainably sourced cosmetics have been dominating the area of skincare products worldwide. Due to their antioxidant and antiaging properties, compounds from cyanobacteria, such as carotenoids and phycobiliproteins, may replace synthetic ingredients in cosmetic formulations and may be used in products such as sunscreens, skincare creams, and makeup. In this study, we evaluated the potential of acetonic and aqueous extracts from cyanobacteria strains of the genera Cyanobium and Leptothoe and from strains within Synechococcales and Oscillatoriales orders, for use in cosmetics. Extractions were sequentially performed with acetone and water. Extracts were firstly analyzed for their toxicity to keratinocytes, fibroblasts, and endothelial cells (HaCAT, 3T3L1 and hCMEC/D3, respectively). The non-cytotoxic extracts were characterized in terms of total proteins, carotenoids, chlorophyll, phenols, phycobiliproteins, and analyzed for their antioxidant potential against the superoxide anion radical (O2•−), and for their ability to inhibit key enzymes associated with the skin aging process. Aqueous extracts were richer in total proteins and phycobiliproteins. The aqueous extracts of Synechococcales cyanobacterium LEGE 181157 and Synechococcales cyanobacterium LEGE 181150 showed the highest value for total proteins (760.81 and 695.25 μg BSA mL−1dry extract, respectively) and the best values regarding O2•− scavenging (IC50 = 63.24 and 112.18 μg mL−1dry extract, respectively) with a significant negative correlation observed (p < 0.01). Moreover, aqueous extracts of Synechococcales cyanobacterium LEGE 181150 and Synechococcales cyanobacterium LEGE 181157 inhibited hyaluronidase, (IC50 of 483.86 and 645.06 μg mL−1dry extract, respectively), with a significant negative correlation with total proteins (p < 0.05), pointing out the contribution of these compounds to the biological activities observed. Acetonic extracts were richer in carotenoids and phenols. Zeaxanthin and β-carotene were predominant among all strains, being present in higher amount in Cyanobium sp. LEGE 07175 (53.08 μg mg−1) and Leptothoe sp. LEGE 181156 (47.89 μg mg−1), respectively. The same strains also showed the highest values for collagenase inhibition at 750 μg mL−1dry extract (32.88 and 36.61%, respectively). Furthermore, Leptothoe sp. LEGE 181156 exhibited the lowest IC50 value for tyrosinase inhibition (465.92 μg mL−1dry extract) and Synechococcales cyanobacterium LEGE 181157 presented the best values for elastase inhibition (IC50 of 380.50 and IC25 of 51.43 μg mL−1dry extract). In general, cyanobacteria extracts demonstrated potential for being used for antiaging purposes, with aqueous extracts being more efficient at free radicals scavenging and acetonic ones at avoiding degradation of dermal matrix components. Full article
(This article belongs to the Special Issue Bioactive Product from Marine Cyanobacteria)
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27 pages, 3327 KiB  
Article
Marine-Derived Actinomycetes: Biodegradation of Plastics and Formation of PHA Bioplastics—A Circular Bioeconomy Approach
by Juliana Oliveira, Pedro L. Almeida, Rita G. Sobral, Nídia D. Lourenço and Susana P. Gaudêncio
Mar. Drugs 2022, 20(12), 760; https://doi.org/10.3390/md20120760 - 1 Dec 2022
Cited by 14 | Viewed by 4334
Abstract
Plastics are present in the majority of daily-use products worldwide. Due to society’s production and consumption patterns, plastics are accumulating in the environment, causing global pollution issues and intergenerational impacts. Our work aims to contribute to the development of solutions and sustainable methods [...] Read more.
Plastics are present in the majority of daily-use products worldwide. Due to society’s production and consumption patterns, plastics are accumulating in the environment, causing global pollution issues and intergenerational impacts. Our work aims to contribute to the development of solutions and sustainable methods to mitigate this pressing problem, focusing on the ability of marine-derived actinomycetes to accelerate plastics biodegradation and produce polyhydroxyalkanoates (PHAs), which are biodegradable bioplastics. The thin plastic films’ biodegradation was monitored by weight loss, changes in the surface chemical structure (Infra-Red spectroscopy FTIR-ATR), and by mechanical properties (tensile strength tests). Thirty-six marine-derived actinomycete strains were screened for their plastic biodegradability potential. Among these, Streptomyces gougerotti, Micromonospora matsumotoense, and Nocardiopsis prasina revealed ability to degrade plastic films—low-density polyethylene (LDPE), polystyrene (PS) and polylactic acid (PLA) in varying conditions, namely upon the addition of yeast extract to the culture media and the use of UV pre-treated thin plastic films. Enhanced biodegradation by these bacteria was observed in both cases. S. gougerotti degraded 0.56% of LDPE films treated with UV radiation and 0.67% of PS films when inoculated with yeast extract. Additionally, N. prasina degraded 1.27% of PLA films when these were treated with UV radiation, and yeast extract was added to the culture medium. The main and most frequent differences observed in FTIR-ATR spectra during biodegradation occurred at 1740 cm−1, indicating the formation of carbonyl groups and an increase in the intensity of the bands, which indicates oxidation. Young Modulus decreased by 30% on average. In addition, S. gougerotti and M. matsumotoense, besides biodegrading conventional plastics (LDPE and PS), were also able to use these as a carbon source to produce degradable PHA bioplastics in a circular economy concept. Full article
(This article belongs to the Special Issue Sustainable Circular Bioeconomy Approaches for the Biotechnological Development of Marine-Derived Products)
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