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Mar. Drugs, Volume 22, Issue 9 (September 2024) – 53 articles

Cover Story (view full-size image): Safracins are compounds with potent broad-spectrum antibacterial and antitumor activities. Safracin B prepared by the fermentation of Pseudomonas poae PMA22 is used to chemically synthesize trabectedin (Yondelis, ET-743), an antitumor agent naturally produced in the marine tunicate, Ecteinascidia turbinata by an uncultivable bacterial symbiont. In this work, we have shown that safracin biosynthesis and its transport into the extracellular medium are precisely regulated by the MexT-MexS regulatory system in the producer strain. The regulatory system activates the expression of safracin tailoring genes (sacI and sacJ) present in the BCG sac synthetic cluster, as well as the genes encoding the multidrug efflux pump MexEF-OpnR, which was found to be a critical production step as it is involved in safracin secretion. View this paper
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18 pages, 337 KiB  
Review
Valorization of the Invasive Blue Crabs (Callinectes sapidus) in the Mediterranean: Nutritional Value, Bioactive Compounds and Sustainable By-Products Utilization
by Rosaria Arena, Giuseppe Renda, Giovanna Ottaviani Aalmo, Frédéric Debeaufort, Concetta Maria Messina and Andrea Santulli
Mar. Drugs 2024, 22(9), 430; https://doi.org/10.3390/md22090430 - 23 Sep 2024
Abstract
The blue crab (Callinectes sapidus), originally from the western Atlantic Ocean, has recently spread to the Mediterranean and is now considered one of the one hundred most invasive species in that region. This opportunistic species, known for its adaptability to different [...] Read more.
The blue crab (Callinectes sapidus), originally from the western Atlantic Ocean, has recently spread to the Mediterranean and is now considered one of the one hundred most invasive species in that region. This opportunistic species, known for its adaptability to different temperatures and salinities, negatively impacts biodiversity and human activities such as fishing and tourism in the Mediterranean. However, the blue crab is gaining interest as a potential food resource due to its high nutritional value and delicate, sweet flavor. Its meat is rich in protein (14% to 30%), omega-3 fatty acids (EPA and DHA) and other essential nutrients beneficial for human health such as vitamins, and minerals. Utilizing this species in the production of new foods could help mitigate the negative impact of its invasiveness and offer economic opportunities. One challenge with this potential resource is the generation of waste. Approximately 6–8 million tonnes of crab shells are produced worldwide each year, leading to disposal problems and concerns regarding environmental sustainability. To improve economic and environmental sustainability, there is a need to valorize these residues, which are an important source of proteins, lipids, chitin, minerals, and pigments that can be processed into high-value-added products. However, especially in areas with industrial pollution, attention should be paid to the heavy metal (Cd and As) contents of blue crab shells. Studies suggest that blue crab by-products can be used in various sectors, reducing environmental impacts, promoting a circular economy, and creating new industrial opportunities. Full article
14 pages, 5614 KiB  
Article
Characterization and Genomic Analyses of dsDNA Vibriophage vB_VpaM_XM1, Representing a New Viral Family
by Zuyun Wei, Xuejing Li, Chunxiang Ai and Hongyue Dang
Mar. Drugs 2024, 22(9), 429; https://doi.org/10.3390/md22090429 - 21 Sep 2024
Abstract
A novel vibriophage vB_VpaM_XM1 (XM1) was described in the present study. Morphological analysis revealed that phage XM1 had Myovirus morphology, with an oblate icosahedral head and a long contractile tail. The genome size of XM1 is 46,056 bp, with a G + C [...] Read more.
A novel vibriophage vB_VpaM_XM1 (XM1) was described in the present study. Morphological analysis revealed that phage XM1 had Myovirus morphology, with an oblate icosahedral head and a long contractile tail. The genome size of XM1 is 46,056 bp, with a G + C content of 42.51%, encoding 69 open reading frames (ORFs). Moreover, XM1 showed a narrow host range, only lysing Vibrio xuii LMG 21346 (T) JL2919, Vibrio parahaemolyticus 1.1997, and V. parahaemolyticus MCCC 1H00029 among the tested bacteria. One-step growth curves showed that XM1 has a 20-min latent period and a burst size of 398 plaque-forming units (PFU)/cell. In addition, XM1 exhibited broad pH, thermal, and salinity stability, as well as strong lytic activity, even at a multiplicity of infection (MOI) of 0.001. Multiple genome comparisons and phylogenetic analyses showed that phage XM1 is grouped in a clade with three other phages, including Vibrio phages Rostov 7, X29, and phi 2, and is distinct from all known viral families that have ratified by the standard genomic analysis of the International Committee on Taxonomy of Viruses (ICTV). Therefore, the above four phages might represent a new viral family, tentatively named Weiviridae. The broad physiological adaptability of phage XM1 and its high lytic activity and host specificity indicated that this novel phage is a good candidate for being used as a therapeutic bioagent against infections caused by certain V. parahaemolyticus strains. Full article
(This article belongs to the Special Issue Marine Bacteriophages and Their Applications)
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19 pages, 8712 KiB  
Article
Synthesis and Characterization of a Novel Chitosan-Based Nanoparticle–Hydrogel Composite System Promising for Skin Wound Drug Delivery
by Yueying Huang, Shuting Hao, Jiayu Chen, Mengyuan Wang, Ziheng Lin and Yanan Liu
Mar. Drugs 2024, 22(9), 428; https://doi.org/10.3390/md22090428 - 21 Sep 2024
Abstract
As a natural preservative, nisin is widely used in the food industry, while its application in biomedicine is limited due to its susceptibility to interference from external conditions. In this study, a nanoparticle–hydrogel composite system was designed to encapsulate and release nisin. Nisin [...] Read more.
As a natural preservative, nisin is widely used in the food industry, while its application in biomedicine is limited due to its susceptibility to interference from external conditions. In this study, a nanoparticle–hydrogel composite system was designed to encapsulate and release nisin. Nisin nanoparticles were identified with a smooth, spherical visual morphology, particle size of 122.72 ± 4.88 nm, polydispersity coefficient of 0.473 ± 0.063, and zeta potential of 23.89 ± 0.37 mV. Based on the sample state and critical properties, three temperature-sensitive hydrogels based on chitosan were ultimately chosen with a rapid gelation time of 112 s, outstanding reticular structure, and optimal swelling ratio of 239.05 ± 7.15%. The composite system exhibited the same antibacterial properties as nisin, demonstrated by the composite system’s inhibition zone diameter of 17.06 ± 0.83 mm, compared to 20.20 ± 0.58 mm for nisin, which was attributed to the prolonged release effect of the hydrogel at the appropriate temperature. The composite system also demonstrated good biocompatibility and safety, making it suitable for application as short-term wound dressings in biomedicine due to its low hemolysis rate of less than 2%. In summary, our nanoparticle-based hydrogel composite system offers a novel application form of nisin while ensuring its stability, thereby deepening and broadening the employment of nisin. Full article
(This article belongs to the Special Issue Application of Marine Chitin and Chitosan, 3rd Edition)
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22 pages, 1190 KiB  
Review
Aquatic Biomaterial Repositories: Comprehensive Guidelines, Recommendations, and Best Practices for Their Development, Establishment, and Sustainable Operation
by Christiana Tourapi, Eleni Christoforou, Susana P. Gaudêncio and Marlen I. Vasquez
Mar. Drugs 2024, 22(9), 427; https://doi.org/10.3390/md22090427 - 20 Sep 2024
Abstract
The alarming pace of species extinction severely threatens terrestrial and aquatic ecosystems, undermining the crucial ecological services vital for environmental sustainability and human well-being. Anthropogenic activities, such as urbanization, agriculture, industrialization, and those inducing climate change, intensify these risks, further imperiling biodiversity. Of [...] Read more.
The alarming pace of species extinction severely threatens terrestrial and aquatic ecosystems, undermining the crucial ecological services vital for environmental sustainability and human well-being. Anthropogenic activities, such as urbanization, agriculture, industrialization, and those inducing climate change, intensify these risks, further imperiling biodiversity. Of particular importance are aquatic organisms, pivotal in biodiscovery and biotechnology. They contribute significantly to natural product chemistry, drug development, and various biotechnological applications. To safeguard these invaluable resources, establishing and maintaining aquatic biomaterial repositories (ABRs) is imperative. This review explores the complex landscape of ABRs, emphasizing the need for standardized procedures from collection to distribution. It identifies key legislative and regulatory frameworks, such as the Nagoya Protocol and EU directives, essential for ensuring responsible and equitable biorepository operations. Drawing on extensive literature and database searches, this study compiles existing recommendations and practices into a cohesive framework with which to guide the establishment and sustainable management of ABRs. Through collaborative efforts and adherence to best practices, ABRs can play a transformative role in the future of marine biotechnology and environmental conservation. Full article
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22 pages, 1573 KiB  
Review
Immunomodulatory Effects of Halichondrin Isolated from Marine Sponges and Its Synthetic Analogs in Oncological Applications
by Dinusha Shiromala Dissanayake, Dineth Pramuditha Nagahawatta, Jung-Suck Lee and You-Jin Jeon
Mar. Drugs 2024, 22(9), 426; https://doi.org/10.3390/md22090426 - 20 Sep 2024
Abstract
Marine natural products comprise unique chemical structures and vast varieties of biological activities. This review aims to summarize halichondrin, a marine natural product, and its synthetic analogs along with its therapeutic properties and mechanisms. Halichondrin and its analogs, derived from marine sponges, exhibit [...] Read more.
Marine natural products comprise unique chemical structures and vast varieties of biological activities. This review aims to summarize halichondrin, a marine natural product, and its synthetic analogs along with its therapeutic properties and mechanisms. Halichondrin and its analogs, derived from marine sponges, exhibit potent antineoplastic properties, making them promising candidates for cancer therapeutics. These compounds, characterized by their complex molecular structures, have demonstrated significant efficacy in inhibiting microtubule dynamics, leading to cell cycle arrest and apoptosis in various cancer cell lines. Several types of halichondrins such as halichondrins B, C, norhalichondrin B, and homohalichondrin B have been discovered with similar anticancer and antitumor characteristics. Since naturally available halichondrins show hurdles in synthesis, recent advancements in synthetic methodologies have enabled the development of several halichondrin analogs, such as E7389 (eribulin), which have shown improved therapeutic indices. Eribulin has shown excellent immunomodulatory properties by several mechanisms such as reprogramming tumor microenvironments, facilitating the infiltration and activation of immune cells, and inhibiting microtubule dynamics. Despite promising results, challenges remain in the synthesis and clinical application of these compounds. This review explores the mechanisms underlying the immunomodulatory activity of halichondrin and its analogs in cancer therapy, along with their clinical applications and potential for future drug development. Full article
(This article belongs to the Special Issue Marine Natural Products with Immunomodulatory Activity)
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12 pages, 2262 KiB  
Perspective
Synthesis of Marine (-)-Pelorol and Future Perspectives
by Antonio Rosales Martínez and Ignacio Rodríguez-García
Mar. Drugs 2024, 22(9), 425; https://doi.org/10.3390/md22090425 - 19 Sep 2024
Abstract
Meroterpenoid-type marine natural compounds have attracted an increasing amount of attention due to their peculiar chemical structures and their potential for the development of therapeutically important probes. Within this group of substances pelorol stands out; it is a natural compound isolated from marine [...] Read more.
Meroterpenoid-type marine natural compounds have attracted an increasing amount of attention due to their peculiar chemical structures and their potential for the development of therapeutically important probes. Within this group of substances pelorol stands out; it is a natural compound isolated from marine organisms with a unique structure and an interesting biological profile. In this article, we summarize and highlight the most interesting aspects of the synthetic procedures towards this compound, which have two common key steps. The first is the coupling of a drimanyl derivative with a compound derived from an arene. The second is a Friedel–Crafts cyclization which forms the C ring of the natural product. Despite the synthetic advances achieved so far, we consider that a more efficient synthetic procedures could be carried out, since their synthetic routes are difficult to scale up due to numerous reaction steps and the limitations imposed by the use of some reagents. In this article, we present a new and versatile retrosynthetic analysis of (-)-pelorol and analogs, which is highly desirable for their easy preparation and subsequent broad study of their biological activities. This is a retrosynthetic route that could improve those reported in the literature in terms of cost-effectiveness. Full article
(This article belongs to the Special Issue Perspectives for the Development of New Multitarget Marine Drugs)
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27 pages, 7852 KiB  
Review
Recent Advances in Anti-Inflammatory Compounds from Marine Microorganisms
by Guihua Yang, Miaoping Lin, Kumaravel Kaliaperumal, Yaqi Lu, Xin Qi, Xiaodong Jiang, Xinya Xu, Chenghai Gao, Yonghong Liu and Xiaowei Luo
Mar. Drugs 2024, 22(9), 424; https://doi.org/10.3390/md22090424 - 18 Sep 2024
Abstract
Marine microbial secondary metabolites with diversified structures have been found as promising sources of anti-inflammatory lead compounds. This review summarizes the sources, chemical structures, and pharmacological properties of anti-inflammatory natural products reported from marine microorganisms in the past three years (2021–2023). Approximately 252 [...] Read more.
Marine microbial secondary metabolites with diversified structures have been found as promising sources of anti-inflammatory lead compounds. This review summarizes the sources, chemical structures, and pharmacological properties of anti-inflammatory natural products reported from marine microorganisms in the past three years (2021–2023). Approximately 252 anti-inflammatory compounds, including 129 new ones, were predominantly obtained from marine fungi and they are structurally divided into polyketides (51.2%), terpenoids (21.0%), alkaloids (18.7%), amides or peptides (4.8%), and steroids (4.3%). This review will shed light on the development of marine microbial secondary metabolites as potential anti-inflammatory lead compounds with promising clinical applications in human health. Full article
(This article belongs to the Special Issue Marine Anti-inflammatory and Antioxidant Agents 4.0)
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12 pages, 1638 KiB  
Article
Staurosporine as a Potential Treatment for Acanthamoeba Keratitis Using Mouse Cornea as an Ex Vivo Model
by Rubén L. Rodríguez-Expósito, Ines Sifaoui, Lizbeth Salazar-Villatoro, Carlos J. Bethencourt-Estrella, José J. Fernández, Ana R. Díaz-Marrero, Robert Sutak, Maritza Omaña-Molina, José E. Piñero and Jacob Lorenzo-Morales
Mar. Drugs 2024, 22(9), 423; https://doi.org/10.3390/md22090423 - 18 Sep 2024
Abstract
Acanthamoeba is a ubiquitous genus of amoebae that can trigger a severe and progressive ocular disease known as Acanthamoeba Keratitis (AK). Furthermore, current treatment protocols are based on the combination of different compounds that are not fully effective. Therefore, an urgent need to [...] Read more.
Acanthamoeba is a ubiquitous genus of amoebae that can trigger a severe and progressive ocular disease known as Acanthamoeba Keratitis (AK). Furthermore, current treatment protocols are based on the combination of different compounds that are not fully effective. Therefore, an urgent need to find new compounds to treat Acanthamoeba infections is clear. In the present study, we evaluated staurosporine as a potential treatment for Acanthamoeba keratitis using mouse cornea as an ex vivo model, and a comparative proteomic analysis was conducted to elucidate a mechanism of action. The obtained results indicate that staurosporine altered the conformation of actin and tubulin in treated trophozoites of A. castellanii. In addition, proteomic analysis of treated trophozoites revealed that this molecule induced overexpression and a downregulation of proteins related to key functions for Acanthamoeba infection pathways. Additionally, the ex vivo assay used validated this model for the study of the pathogenesis and therapies of AK. Finally, staurosporine eliminated the entire amoebic population and prevented the adhesion and infection of amoebae to the epithelium of treated mouse corneas. Full article
(This article belongs to the Special Issue Marine-Derived Bioactive Substances and Their Mechanisms of Action)
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38 pages, 5610 KiB  
Article
Morphological, Toxicological, and Biochemical Characterization of Two Species of Gambierdiscus from Bahía de La Paz, Gulf of California
by Leyberth José Fernández-Herrera, Erick Julián Núñez-Vázquez, Francisco E. Hernández-Sandoval, Daniel Octavio Ceseña-Ojeda, Sara García-Davis, Andressa Teles, Marte Virgen-Félix and Dariel Tovar-Ramírez
Mar. Drugs 2024, 22(9), 422; https://doi.org/10.3390/md22090422 - 16 Sep 2024
Abstract
We describe five new isolates of two Gambierdiscus species from Bahía de La Paz in the southern Gulf of California. Batch cultures of Gambierdiscus were established for morphological characterization using light microscopy (LM) and scanning electron microscopy (SEM). Pigment and amino acid profiles [...] Read more.
We describe five new isolates of two Gambierdiscus species from Bahía de La Paz in the southern Gulf of California. Batch cultures of Gambierdiscus were established for morphological characterization using light microscopy (LM) and scanning electron microscopy (SEM). Pigment and amino acid profiles were also analyzed using high-performance liquid chromatography (HPLC-UV and HPLC-DAD). Finally, toxicity (CTX-like and MTX-like activity) was evaluated using the Artemia salina assay (ARTOX), mouse assay (MBA), marine fish assay (MFA), and fluorescent receptor binding assay (fRBA). These strains were identified as Gambierdiscus cf. caribaeus and Gambierdiscus cf. carpenteri. Toxicity for CTX-like and MTX-like activity was confirmed in all evaluated clones. Seven pigments were detected, with chlorophyll a, pyridine, Chl2, and diadinoxanthin being particularly noteworthy. For the first time, a screening of the amino acid profile of Gambierdiscus from the Pacific Ocean was conducted, which showed 14 amino acids for all strains except histidine, which was only present in G. cf. caribeaus. We report the presence of Gambierdiscus and Fukuyoa species in the Mexican Pacific, where ciguatera fish poisoning (CFP) cases have occurred. Full article
(This article belongs to the Special Issue Commemorating the Launch of the Section "Marine Toxins")
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17 pages, 5163 KiB  
Article
Fermented Fish Collagen Attenuates Melanogenesis via Decreasing UV-Induced Oxidative Stress
by Kyung-A Byun, So Young Lee, Seyeon Oh, Sosorburam Batsukh, Jong-Won Jang, Bae-Jin Lee, Kyoung-min Rheu, Sichao Li, Min-Seok Jeong, Kuk Hui Son and Kyunghee Byun
Mar. Drugs 2024, 22(9), 421; https://doi.org/10.3390/md22090421 - 15 Sep 2024
Abstract
Excessive melanogenesis leads to hyperpigmentation-related cosmetic problems. UV exposure increases oxidative stress, which promotes melanogenesis-related signal pathways such as the PKA, microphthalmia-associated transcription factor (MITF), tyrosinase (TYR), tyrosinase-related protein-1 (TRP1), and tyrosinase-related protein-2 (TRP2) pathways. Glycine is a source of endogenous antioxidants, including [...] Read more.
Excessive melanogenesis leads to hyperpigmentation-related cosmetic problems. UV exposure increases oxidative stress, which promotes melanogenesis-related signal pathways such as the PKA, microphthalmia-associated transcription factor (MITF), tyrosinase (TYR), tyrosinase-related protein-1 (TRP1), and tyrosinase-related protein-2 (TRP2) pathways. Glycine is a source of endogenous antioxidants, including glutathione. Fermented fish collagen (FC) contains glycine; thus, we evaluated the effect of FC on decreasing melanogenesis via decreasing oxidative stress. The glycine receptor (GlyR) and glycine transporter-1 (GlyT1) levels were decreased in UV-irradiated keratinocytes; however, the expression levels of these proteins increased upon treatment with FC. The FC decreased oxidative stress, as indicated by the decreasing expression of NOX1/2/4, increased expression of GSH/GSSG, increased SOD activity, and decreased 8-OHdG expression in UV-irradiated keratinocytes. Administration of conditioned media from FC-treated keratinocytes to melanocytes led to decreased p38, PKC, MITF, TRP1, and TRP2 expression. These changes induced by the FC were also observed in UV-irradiated animal skin. FC treatment increased the expression of GlyR and GlyT, which was accompanied by decreased oxidative stress in the UV-irradiated skin. Moreover, the FC negatively regulated the melanogenesis signaling pathways, leading to decreased melanin content in the UV-irradiated skin. In conclusion, FC decreased UV-induced oxidative stress and melanogenesis in melanocytes and animal skin. FC could be used in the treatment of UV-induced hyperpigmentation problems. Full article
(This article belongs to the Special Issue Marine Cosmeceuticals)
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15 pages, 3407 KiB  
Article
In Vitro In Silico Screening Strategy and Mechanism of Novel Tyrosinase Inhibitory Peptides from Nacre of Hyriopsis cumingii
by Haisheng Lin, Fei Li, Jiaao Kang, Shaohe Xie, Xiaoming Qin, Jialong Gao, Zhongqin Chen, Wenhong Cao, Huina Zheng and Wenkui Song
Mar. Drugs 2024, 22(9), 420; https://doi.org/10.3390/md22090420 - 15 Sep 2024
Abstract
For thousands of years, pearl and nacre powders have been important traditional Chinese medicines known for their skin whitening effects. To prepare the enzymatic hydrolysates of Hyriopsis cumingii nacre powder (NP-HCH), complex enzymatic hydrolysis by pineapple protease and of neutral protease was carried [...] Read more.
For thousands of years, pearl and nacre powders have been important traditional Chinese medicines known for their skin whitening effects. To prepare the enzymatic hydrolysates of Hyriopsis cumingii nacre powder (NP-HCH), complex enzymatic hydrolysis by pineapple protease and of neutral protease was carried out after the powder was pre-treated with a high-temperature and high-pressure method. The peptides were identified using LC-MS/MS and picked out through molecular docking and molecular dynamics simulations. Subsequently, the tyrosinase inhibitory and antioxidant properties of novel tyrosinase inhibitory peptides were investigated in vitro. In addition, the enzymatic activity of tyrosinase in B16F10 cells as well as melanin content and antioxidant enzyme levels were also examined. The results showed that a tyosinase inhibitory peptide (Tyr-Pro-Asn-Pro-Tyr, YPNPY) with an efficient IC50 value of 0.545 ± 0.028 mM was identified. The in vitro interaction results showed that YPNPY is a reversible competitive inhibitor of tyrosinase, suggesting that it binds to the free enzyme. The B16F10 cell whitening test revealed that YPNPY can reduce the melanin content of B16F10 cells by directly inhibiting the activity of intracellular tyrosinase. Additionally, it indirectly affects melanin production by acting as an antioxidant. These results suggest that YPNPY could be widely used as a tyrosinase inhibitor in whitening foods and drugs. Full article
(This article belongs to the Special Issue Marine Alkaloids: Sources, Discovery, Diversity, and Bioactivities)
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14 pages, 5606 KiB  
Article
Enantioselectivity in Vanadium-Dependent Haloperoxidases of Different Marine Sources for Sulfide Oxidation to Sulfoxides
by Yun-Han Zhang, Ya-Ting Zou, Yong-Yi Zeng, Lan Liu and Bi-Shuang Chen
Mar. Drugs 2024, 22(9), 419; https://doi.org/10.3390/md22090419 - 14 Sep 2024
Abstract
This study explores the reasons behind the variations in the enantioselectivity of the sulfoxidation of methyl phenyl sulfide by marine-derived vanadium-dependent haloperoxidases (VHPOs). Twelve new VHPOs of marine organisms were overexpressed, purified, and tested for their ability to oxidize sulfide. Most of these [...] Read more.
This study explores the reasons behind the variations in the enantioselectivity of the sulfoxidation of methyl phenyl sulfide by marine-derived vanadium-dependent haloperoxidases (VHPOs). Twelve new VHPOs of marine organisms were overexpressed, purified, and tested for their ability to oxidize sulfide. Most of these marine enzymes exhibited nonenantioselective behavior, underscoring the uniqueness of AnVBPO from the brown seaweed Ascophyllum nodosum and CpVBPO from the red seaweed Corallina pilulifera, which produce (R)- and (S)-sulfoxides, respectively. The enantioselective sulfoxidation pathway is likely due to direct oxygen transfer within the VHPO active site. This was demonstrated through molecular docking and molecular dynamics simulations, which revealed differences in the positioning of sulfide within AnVBPO and CpVBPO, thus explaining their distinct enantioselectivities. Nonenantioselective VHPOs probably follow a different oxidation pathway, initiating with sulfide oxidation to form a positively charged radical. Further insights were gained from studying the catalytic effect of VO43− on H2O2-driven sulfoxidation. This research improves the understanding of VHPO-mediated sulfoxidation and aids in developing biocatalysts for sulfoxide synthesis. Full article
(This article belongs to the Special Issue Advances of Marine-Derived Enzymes)
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20 pages, 4189 KiB  
Article
Regulation of Safracin Biosynthesis and Transport in Pseudomonas poae PMA22
by J. Gerardo Hernández Delgado, Miguel G. Acedos, Fernando de la Calle, Pilar Rodríguez, José Luis García and Beatriz Galán
Mar. Drugs 2024, 22(9), 418; https://doi.org/10.3390/md22090418 - 13 Sep 2024
Abstract
Pseudomonas poae PMA22 produces safracins, a family of compounds with potent broad-spectrum anti-bacterial and anti-tumor activities. The safracins’ biosynthetic gene cluster (BGC sac) consists of 11 ORFs organized in two divergent operons (sacABCDEFGHK and sacIJ) that are controlled by Pa [...] Read more.
Pseudomonas poae PMA22 produces safracins, a family of compounds with potent broad-spectrum anti-bacterial and anti-tumor activities. The safracins’ biosynthetic gene cluster (BGC sac) consists of 11 ORFs organized in two divergent operons (sacABCDEFGHK and sacIJ) that are controlled by Pa and Pi promoters. Contiguous to the BGC sac, we have located a gene that encodes a putative global regulator of the LysR family annotated as MexT that was originally described as a transcriptional activator of the MexEF-OprN multidrug efflux pump in Pseudomonas. Through both in vitro and in vivo experiments, we have demonstrated the involvement of the dual regulatory system MexT-MexS on the BGC sac expression acting as an activator and a repressor, respectively. The MexEF-OprN transport system of PMA22, also controlled by MexT, was shown to play a fundamental role in the metabolism of safracin. The overexpression of mexEF-oprN in PMA22 resulted in fourfold higher production levels of safracin. These results illustrate how a pleiotropic regulatory system can be critical to optimizing the production of tailored secondary metabolites, not only through direct interaction with the BGC promoters, but also by controlling their transport. Full article
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18 pages, 7588 KiB  
Article
Optimizing Antioxidant Potential: Factorial Design-Based Formulation of Fucoidan and Gallic Acid-Conjugated Dextran Blends
by Cynthia Haynara Ferreira Silva, Maylla Maria Correia Leite Silva, Weslley Souza Paiva, Mayara Jane Campos de Medeiros, Moacir Fernandes Queiroz, Luciana Duarte Martins Matta, Everaldo Silvino dos Santos and Hugo Alexandre Oliveira Rocha
Mar. Drugs 2024, 22(9), 417; https://doi.org/10.3390/md22090417 - 13 Sep 2024
Abstract
The role of oxidative stress in health and homeostasis has generated interest in the scientific community due to its association with cardiovascular and neurodegenerative diseases, cancer, and other diseases. Therefore, extensive research seeks to identify new exogenous antioxidant compounds for supplementation. Polysaccharides are [...] Read more.
The role of oxidative stress in health and homeostasis has generated interest in the scientific community due to its association with cardiovascular and neurodegenerative diseases, cancer, and other diseases. Therefore, extensive research seeks to identify new exogenous antioxidant compounds for supplementation. Polysaccharides are recognized for their antioxidant properties. However, polysaccharide chemical modifications are often necessary to enhance these properties. Therefore, dextran was conjugated with gallic acid (Dex-Gal) and later combined with fucoidan A (FucA) to formulate blends aimed at achieving superior antioxidant activity compared to individual polysaccharides. A factorial design was employed to combine FucA and Dex-Gal in different proportions, resulting in five blends (BLD1, BLD2, BLD3, BLD4, and BLD5). An analysis of surface graphs from in vitro antioxidant tests, including total antioxidant capacity (TAC), reducing power, and hydroxyl radical scavenging, guided the selection of BLD4 as the optimal formulation. Tests on 3T3 fibroblasts under various conditions of oxidative stress induced by hydrogen peroxide revealed that BLD4 provided enhanced protection compared to its isolated components. The BLD4 formulation, resulting from the combination of Dex-Gal and FucA, showed promise as an antioxidant strategy, outperforming its individual components and suggesting its potential as a supplement to mitigate oxidative stress in adverse health conditions. Full article
(This article belongs to the Special Issue Polysaccharides from Marine Environment)
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80 pages, 28457 KiB  
Review
A Chemical Toolbox to Unveil Synthetic Nature-Inspired Antifouling (NIAF) Compounds
by Ana Rita Neves, Sara Godinho, Catarina Gonçalves, Ana Sara Gomes, Joana R. Almeida, Madalena Pinto, Emília Sousa and Marta Correia-da-Silva
Mar. Drugs 2024, 22(9), 416; https://doi.org/10.3390/md22090416 - 12 Sep 2024
Abstract
The current scenario of antifouling (AF) strategies to prevent the natural process of marine biofouling is based in the use of antifouling paints containing different active ingredients, believed to be harmful to the marine environment. Compounds called booster biocides are being used with [...] Read more.
The current scenario of antifouling (AF) strategies to prevent the natural process of marine biofouling is based in the use of antifouling paints containing different active ingredients, believed to be harmful to the marine environment. Compounds called booster biocides are being used with copper as an alternative to the traditionally used tributyltin (TBT); however, some of them were recently found to accumulate in coastal waters at levels that are deleterious for marine organisms. More ecological alternatives were pursued, some of them based on the marine organism mechanisms’ production of specialized metabolites with AF activity. However, despite the investment in research on AF natural products and their synthetic analogues, many studies showed that natural AF alternatives do not perform as well as the traditional metal-based ones. In the search for AF agents with better performance and to understand which molecular motifs were responsible for the AF activity of natural compounds, synthetic analogues were produced and investigated for structure–AF activity relationship studies. This review is a comprehensive compilation of AF compounds synthesized in the last two decades with highlights on the data concerning their structure–activity relationship, providing a chemical toolbox for researchers to develop efficient nature-inspired AF agents. Full article
(This article belongs to the Special Issue Marine Natural Products with Antifouling Activity, 3rd Edition)
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20 pages, 7968 KiB  
Article
Blood Coagulation Activities and Influence on DNA Condition of Alginate—Calcium Composites Prepared by Freeze-Drying Technique
by Małgorzata Świerczyńska, Paulina Król, César I. Hernández Vázquez, Klaudia Piekarska, Katarzyna Woźniak, Michał Juszczak, Zdzisława Mrozińska and Marcin H. Kudzin
Mar. Drugs 2024, 22(9), 415; https://doi.org/10.3390/md22090415 - 10 Sep 2024
Abstract
The aim of this research was to synthesize and characterize alginate–calcium composites using a freeze-drying method, with a focus on their potential applications in biomedicine. This study specifically explored the biochemical properties of these composites, emphasizing their role in blood coagulation and their [...] Read more.
The aim of this research was to synthesize and characterize alginate–calcium composites using a freeze-drying method, with a focus on their potential applications in biomedicine. This study specifically explored the biochemical properties of these composites, emphasizing their role in blood coagulation and their capacity to interact with DNA. Additionally, the research aimed to assess how the cross-linking process influences the structural and chemical characteristics of the composites. Detailed analyses, including microscopic examination, surface area assessment, and atomic absorption spectrometry, yielded significant results. The objective of this study was to examine the impact of calcium chloride concentration on the calcium content in alginate composites. Specifically, the study assessed how varying concentrations of the cross-linking solution (ranging from 0.5% to 2%) influence the calcium ion saturation within the composites. This investigation is essential for understanding the physicochemical properties of the materials, including calcium content, porosity, and specific surface area. The results are intended to identify the optimal cross-linking conditions that maximize calcium enrichment efficiency while preserving the material’s structural integrity. The study found that higher calcium chloride concentrations in alginate cross-linking improve the formation of a porous structure, enhanced by two-stage freeze-drying. Increased calcium levels led to a larger surface area and pore volume, and significantly higher calcium content. Furthermore, assays of activated partial thromboplastin time (aPTT) showed a reduction in clotting time for alginate composites containing calcium ions, indicating their potential as hemostatic agents. The aPTT test showed shorter clotting times with higher calcium ion concentrations, without enhanced activation of the extrinsic clotting pathway. The developed alginate material with calcium effectively supports hemostasis and reduces the risk of infection. The study also explored the capacity of these composites to interact with and modify the structure of plasmid DNA, underscoring their potential for future biomedical applications. Full article
(This article belongs to the Section Biomaterials of Marine Origin)
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16 pages, 3244 KiB  
Article
Genome Analysis of a Potential Novel Vibrio Species Secreting pH- and Thermo-Stable Alginate Lyase and Its Application in Producing Alginate Oligosaccharides
by Ke Bao, Miao Yang, Qianhuan Sun, Kaishan Zhang and Huiqin Huang
Mar. Drugs 2024, 22(9), 414; https://doi.org/10.3390/md22090414 - 10 Sep 2024
Abstract
Alginate lyase is an attractive biocatalyst that can specifically degrade alginate to produce oligosaccharides, showing great potential for industrial and medicinal applications. Herein, an alginate-degrading strain HB236076 was isolated from Sargassum sp. in Qionghai, Hainan, China. The low 16S rRNA gene sequence identity [...] Read more.
Alginate lyase is an attractive biocatalyst that can specifically degrade alginate to produce oligosaccharides, showing great potential for industrial and medicinal applications. Herein, an alginate-degrading strain HB236076 was isolated from Sargassum sp. in Qionghai, Hainan, China. The low 16S rRNA gene sequence identity (<98.4%), ANI value (<71.9%), and dDDH value (<23.9%) clearly indicated that the isolate represented a potential novel species of the genus Vibrio. The genome contained two chromosomes with lengths of 3,007,948 bp and 874,895 bp, respectively, totaling 3,882,843 bp with a G+C content of 46.5%. Among 3482 genes, 3332 protein-coding genes, 116 tRNA, and 34 rRNA sequences were predicted. Analysis of the amino acid sequences showed that the strain encoded 73 carbohydrate-active enzymes (CAZymes), predicting seven PL7 (Alg1–7) and two PL17 family (Alg8, 9) alginate lyases. The extracellular alginate lyase from strain HB236076 showed the maximum activity at 50 °C and pH 7.0, with over 90% activity measured in the range of 30–60 °C and pH 6.0–10.0, exhibiting a wide range of temperature and pH activities. The enzyme also remained at more than 90% of the original activity at a wide pH range (3.0–9.0) and temperature below 50 °C for more than 2 h, demonstrating significant thermal and pH stabilities. Fe2+ had a good promoting effect on the alginate lyase activity at 10 mM, increasing by 3.5 times. Thin layer chromatography (TLC) and electrospray ionization mass spectrometry (ESI-MS) analyses suggested that alginate lyase in fermentation broth could catalyze sodium alginate to produce disaccharides and trisaccharides, which showed antimicrobial activity against Shigella dysenteriae, Aeromonas hydrophila, Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli. This research provided extended insights into the production mechanism of alginate lyase from Vibrio sp. HB236076, which was beneficial for further application in the preparation of pH-stable and thermo-stable alginate lyase and alginate oligosaccharides. Full article
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20 pages, 849 KiB  
Article
pH-Dependent Extraction of Antioxidant Peptides from Red Seaweed Palmaria palmata: A Sequential Approach
by Sakhi Ghelichi, Ann-Dorit Moltke Sørensen, Grazielle Náthia-Neves and Charlotte Jacobsen
Mar. Drugs 2024, 22(9), 413; https://doi.org/10.3390/md22090413 - 10 Sep 2024
Abstract
This study employed a diverse approach to extract antioxidant peptides from red seaweed Palmaria palmata, recognized for its comparatively high protein content. Initially, an aqueous extraction of the entire seaweed was performed, followed by enzymatic hydrolysis of the solid residues prepared from [...] Read more.
This study employed a diverse approach to extract antioxidant peptides from red seaweed Palmaria palmata, recognized for its comparatively high protein content. Initially, an aqueous extraction of the entire seaweed was performed, followed by enzymatic hydrolysis of the solid residues prepared from the first step. The effects of three different pH levels (3, 6, and 9) during the aqueous extraction were also examined. Results indicated that the solid fraction from the sequential extraction process contained significantly higher levels of proteins and amino acids than other fractions (p < 0.05). Furthermore, the solid fractions (IC50 ranging from 2.29 to 8.15 mg.mL−1) demonstrated significantly greater free radical scavengers than the liquid fractions (IC50 ranging from 9.03 to 10.41 mg.mL−1 or not obtained at the highest concentration tested) at both stages of extraction (p < 0.05). Among the solid fractions, those produced fractions under alkaline conditions were less effective in radical scavenging than the produced fractions under acidic or neutral conditions. The fractions with most effective metal ion chelating activity were the solid fractions from the enzymatic stage, particularly at pH 3 (IC50 = 0.63 ± 0.04 mg.mL−1) and pH 6 (IC50 = 0.89 ± 0.07 mg.mL−1), which were significantly more effective than those from the initial extraction stage (p < 0.05). Despite no significant difference in the total phenolic content between these solid fractions and their corresponding liquid fractions (3.79 ± 0.05 vs. 3.48 ± 0.02 mg.mL−1 at pH 3 and 2.43 ± 0.22 vs. 2.51 ± 0.00 mg.mL−1 at pH 6) (p > 0.05), the observed antioxidant properties may be attributed to bioactive amino acids such as histidine, glutamic acid, aspartic acid, tyrosine, and methionine, either as free amino acids or within proteins and peptides. Full article
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14 pages, 4314 KiB  
Article
Screening of Lipid-Reducing Activity and Cytotoxicity of the Exometabolome from Cyanobacteria
by Rúben Luz, Rita Cordeiro, Vítor Gonçalves, Vitor Vasconcelos and Ralph Urbatzka
Mar. Drugs 2024, 22(9), 412; https://doi.org/10.3390/md22090412 - 10 Sep 2024
Abstract
Cyanobacteria are rich producers of secondary metabolites, excreting some of these to the culture media. However, the exometabolome of cyanobacteria has been poorly studied, and few studies have dwelled on its characterization and bioactivity assessment. In this work, exometabolomes of 56 cyanobacterial strains [...] Read more.
Cyanobacteria are rich producers of secondary metabolites, excreting some of these to the culture media. However, the exometabolome of cyanobacteria has been poorly studied, and few studies have dwelled on its characterization and bioactivity assessment. In this work, exometabolomes of 56 cyanobacterial strains were characterized by HR-ESI-LC-MS/MS. Cytotoxicity was assessed on two carcinoma cell lines, HepG2 and HCT116, while the reduction in lipids was tested in zebrafish larvae and in a steatosis model with fatty acid-overloaded human liver cells. The exometabolome analysis using GNPS revealed many complex clusters of unique compounds in several strains, with no identifications in public databases. Three strains reduced viability in HCT116 cells, namely Tolypotrichaceae BACA0428 (30.45%), Aphanizomenonaceae BACA0025 (40.84%), and Microchaetaceae BACA0110 (46.61%). Lipid reduction in zebrafish larvae was only observed by exposure to Dulcicalothrix sp. BACA0344 (60%). The feature-based molecular network shows that this bioactivity was highly correlated with two flavanones, a compound class described in the literature to have lipid reduction activity. The exometabolome characterization of cyanobacteria strains revealed a high chemodiversity, which supports it as a source for novel bioactive compounds, despite most of the time being overlooked. Full article
(This article belongs to the Collection Bioactive Compounds from Marine Plankton)
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23 pages, 2764 KiB  
Review
Enzymes from Fishery and Aquaculture Waste: Research Trends in the Era of Artificial Intelligence and Circular Bio-Economy
by Zied Khiari
Mar. Drugs 2024, 22(9), 411; https://doi.org/10.3390/md22090411 - 10 Sep 2024
Abstract
In the era of the blue bio-economy, which promotes the sustainable utilization and exploitation of marine resources for economic growth and development, the fisheries and aquaculture industries still face huge sustainability issues. One of the major challenges of these industries is associated with [...] Read more.
In the era of the blue bio-economy, which promotes the sustainable utilization and exploitation of marine resources for economic growth and development, the fisheries and aquaculture industries still face huge sustainability issues. One of the major challenges of these industries is associated with the generation and management of wastes, which pose a serious threat to human health and the environment if not properly treated. In the best-case scenario, fishery and aquaculture waste is processed into low-value commodities such as fishmeal and fish oil. However, this renewable organic biomass contains a number of highly valuable bioproducts, including enzymes, bioactive peptides, as well as functional proteins and polysaccharides. Marine-derived enzymes are known to have unique physical, chemical and catalytic characteristics and are reported to be superior to those from plant and animal origins. Moreover, it has been established that enzymes from marine species possess cold-adapted properties, which makes them interesting from technological, economic and sustainability points of view. Therefore, this review centers around enzymes from fishery and aquaculture waste, with a special focus on proteases, lipases, carbohydrases, chitinases and transglutaminases. Additionally, the use of fishery and aquaculture waste as a substrate for the production of industrially relevant microbial enzymes is discussed. The application of emerging technologies (i.e., artificial intelligence and machine learning) in microbial enzyme production is also presented. Full article
(This article belongs to the Special Issue Enzymes from Marine By-Products and Wastes)
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15 pages, 6260 KiB  
Article
Altechromone A Ameliorates Inflammatory Bowel Disease by Inhibiting NF-κB and NLRP3 Pathways
by Lei Li, Jing Huang, Lixin Feng, Liyan Xu, Houwen Lin, Kechun Liu, Xiaobin Li and Rongchun Wang
Mar. Drugs 2024, 22(9), 410; https://doi.org/10.3390/md22090410 - 9 Sep 2024
Abstract
Altechromone A, also known as 2,5-dimethyl-7-hydroxychromone, is a hydroxyketone containing one hydroxyl and one ketone group. In this study, we isolated Altechromone A from the marine-derived fungus Penicillium Chrysogenum (XY-14-0-4). Previous reports show that Altechromone A has various activities including tumor suppression, antibacterial, [...] Read more.
Altechromone A, also known as 2,5-dimethyl-7-hydroxychromone, is a hydroxyketone containing one hydroxyl and one ketone group. In this study, we isolated Altechromone A from the marine-derived fungus Penicillium Chrysogenum (XY-14-0-4). Previous reports show that Altechromone A has various activities including tumor suppression, antibacterial, and antiviral activities. However, there is no study about its anti-inflammatory activity in inflammatory bowel disease (IBD). Here, we assess the anti-inflammatory activity, especially in IBD, and its potential mechanism using the zebrafish model. Our results indicated that Altechromone A has anti-inflammatory activity in a CuSO4-, tail-cutting-, and LPS-induced inflammatory model in zebrafish, respectively. In addition, Altechromone A greatly reduced the number of neutrophils, improved intestinal motility and efflux efficiency, alleviated intestinal damage, and reduced reactive oxygen species production in the TNBS-induced IBD zebrafish model. The transcriptomics sequencing and real-time qPCR indicated that Altechromone A inhibited the expression of pro-inflammatory genes including TNF-α, NF-κB, IL-1, IL-1β, IL-6, and NLRP3. Therefore, these data indicate that Altechromone A exhibits therapeutic effects in IBD by inhibiting the inflammatory response. Full article
(This article belongs to the Special Issue Zebrafish Models in Marine Drug Discovery)
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15 pages, 31783 KiB  
Article
Exploring the Diversity and Specificity of Secondary Biosynthetic Potential in Rhodococcus
by Gang-Ao Hu, Yue Song, Shi-Yi Liu, Wen-Chao Yu, Yan-Lei Yu, Jian-Wei Chen, Hong Wang and Bin Wei
Mar. Drugs 2024, 22(9), 409; https://doi.org/10.3390/md22090409 - 6 Sep 2024
Abstract
The actinomycete genus Rhodococcus is known for its diverse biosynthetic enzymes, with potential in pollutant degradation, chemical biocatalysis, and natural product exploration. Comparative genomics have analyzed the distribution patterns of non-ribosomal peptide synthetases (NRPSs) in Rhodococcus. The diversity and specificity of its [...] Read more.
The actinomycete genus Rhodococcus is known for its diverse biosynthetic enzymes, with potential in pollutant degradation, chemical biocatalysis, and natural product exploration. Comparative genomics have analyzed the distribution patterns of non-ribosomal peptide synthetases (NRPSs) in Rhodococcus. The diversity and specificity of its secondary metabolism offer valuable insights for exploring natural products, yet remain understudied. In the present study, we analyzed the distribution patterns of biosynthetic gene clusters (BGCs) in the most comprehensive Rhodococcus genome data to date. The results show that 86.5% of the gene cluster families (GCFs) are only distributed in a specific phylogenomic-clade of Rhodococcus, with the most predominant types of gene clusters being NRPS and ribosomally synthesized and post-translationally modified peptides (RiPPs). In-depth mining of RiPP gene clusters revealed that Rhodococcus encodes many clade-specific novel RiPPs, with thirteen core peptides showing antibacterial potential. High-throughput elicitor screening (HiTES) and non-targeted metabolomics revealed that a marine-derived Rhodococcus strain produces a large number of new aurachin-like compounds when exposed to specific elicitors. The present study highlights the diversity and specificity of secondary biosynthetic potential in Rhodococcus, and provides valuable information for the targeted exploration of novel natural products from Rhodococcus, especially for phylogenomic-clade-specific metabolites. Full article
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17 pages, 2715 KiB  
Article
Sphaerococcenol A Derivatives: Design, Synthesis, and Cytotoxicity
by Dídia Sousa, Milene A. G. Fortunato, Joana Silva, Mónica Pingo, Alice Martins, Carlos A. M. Afonso, Rui Pedrosa, Filipa Siopa and Celso Alves
Mar. Drugs 2024, 22(9), 408; https://doi.org/10.3390/md22090408 - 5 Sep 2024
Abstract
Sphaerococcenol A is a cytotoxic bromoditerpene biosynthesized by the red alga Sphaerococcus coronopifolius. A series of its analogues (16) was designed and semi-synthesized using thiol-Michael additions and enone reduction, and the structures of these analogues were characterized by [...] Read more.
Sphaerococcenol A is a cytotoxic bromoditerpene biosynthesized by the red alga Sphaerococcus coronopifolius. A series of its analogues (16) was designed and semi-synthesized using thiol-Michael additions and enone reduction, and the structures of these analogues were characterized by spectroscopic methods. Cytotoxic analyses (1–100 µM; 24 h) were accomplished on A549, DU-145, and MCF-7 cells. The six novel sphaerococcenol A analogues displayed an IC50 range between 14.31 and 70.11 µM on A549, DU-145, and MCF-7 malignant cells. Compound 1, resulting from the chemical addition of 4-methoxybenzenethiol, exhibited the smallest IC50 values on the A549 (18.70 µM) and DU-145 (15.82 µM) cell lines, and compound 3, resulting from the chemical addition of propanethiol, exhibited the smallest IC50 value (14.31 µM) on MCF-7 cells. The highest IC50 values were exhibited by compound 4, suggesting that the chemical addition of benzylthiol led to a loss of cytotoxic activity. The remaining chemical modifications were not able to potentiate the cytotoxicity of the original compounds. Regarding A549 cell viability, analogue 1 exhibited a marked effect on mitochondrial function, which was accompanied by an increase in ROS levels, Caspase-3 activation, and DNA fragmentation and condensation. This study opens new avenues for research by exploring sphaerococcenol A as a scaffold for the synthesis of novel bioactive molecules. Full article
(This article belongs to the Special Issue Marine Natural Products as Anticancer Agents 3.0)
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16 pages, 4560 KiB  
Article
The Cytochalasins and Polyketides from a Mangrove Endophytic Fungus Xylaria arbuscula QYF
by Qi Tan, Xinyu Ye, Siqi Fu, Yihao Yin, Yufeng Liu, Jianying Wu, Fei Cao, Bo Wang, Tingshun Zhu, Wencong Yang and Zhigang She
Mar. Drugs 2024, 22(9), 407; https://doi.org/10.3390/md22090407 - 5 Sep 2024
Abstract
Twelve compounds, including four undescribed cytochalasins, xylariachalasins A–D (14), four undescribed polyketides (58), and four known cytochalasins (912), were isolated from the mangrove endophytic fungus Xylaria arbuscula QYF. Their structures and [...] Read more.
Twelve compounds, including four undescribed cytochalasins, xylariachalasins A–D (14), four undescribed polyketides (58), and four known cytochalasins (912), were isolated from the mangrove endophytic fungus Xylaria arbuscula QYF. Their structures and absolute configurations were established by extensive spectroscopic analyses (1D and 2D NMR, HRESIMS), electronic circular dichroism (ECD) calculations, 13C NMR calculation and DP4+ analysis, single-crystal X-ray diffraction, and the modified Mosher ester method. Compounds 1 and 2 are rare cytochalasin hydroperoxides. In bioactivity assays, Compound 2 exhibited moderate antimicrobial activities against Staphylococcus aureus and Candida albicans with MIC values of 12.5 μM for both Compound 10 exhibited significant cytotoxic activity against MDA-MB-435 with an IC50 value of 3.61 ± 1.60 μM. Full article
(This article belongs to the Special Issue Pharmacological Potential of Marine Natural Products, 2nd Edition)
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26 pages, 1747 KiB  
Article
Stress-Induced Production of Bioactive Oxylipins in Marine Microalgae
by Amandyne Linares-Maurizi, Rana Awad, Anaelle Durbec, Guillaume Reversat, Valérie Gros, Jean-Marie Galano, Justine Bertrand-Michel, Thierry Durand, Rémi Pradelles, Camille Oger and Claire Vigor
Mar. Drugs 2024, 22(9), 406; https://doi.org/10.3390/md22090406 - 4 Sep 2024
Viewed by 152
Abstract
Microalgae, stemming from a complex evolutionary lineage, possess a metabolic composition influenced by their evolutionary journey. They have the capacity to generate diverse polyunsaturated fatty acids (PUFAs), akin to those found in terrestrial plants and oily fish. Also, because of their numerous double [...] Read more.
Microalgae, stemming from a complex evolutionary lineage, possess a metabolic composition influenced by their evolutionary journey. They have the capacity to generate diverse polyunsaturated fatty acids (PUFAs), akin to those found in terrestrial plants and oily fish. Also, because of their numerous double bonds, these metabolic compounds are prone to oxidation processes, leading to the creation of valuable bioactive molecules called oxylipins. Moreover, owing to their adaptability across various environments, microalgae offer an intriguing avenue for biosynthesizing these compounds. Thus, modifying the culture conditions could potentially impact the profiles of oxylipins. Indeed, the accumulation of oxylipins in microalgae is subject to the influence of growth conditions, nutrient availability, and stressors, and adjusting these factors can enhance their production in microalgae culture. Consequently, the present study scrutinized the LC-MS/MS profiles of oxylipins from three marine microalgae species (two Haptagophytes and one Chlorophyte) cultivated in 1 L of photobioreactors under varying stress-inducing conditions, such as the introduction of H2O2, EtOAc, and NaCl, during their exponential growth phase. Approximately 50 oxylipins were identified, exhibiting different concentrations depending on the species and growth circumstances. This research suggests that microalgae metabolisms can be steered toward the production of bioactive oxylipins through modifications in the culture conditions. In this instance, the application of a low dose of hydrogen peroxide to Mi 124 appears to stimulate the production of nonenzymatic oxylipins. For Mi136, it is the application of salt stress that seems to increase the overall production of oxylipins. In the case of Mi 168, either a low concentration of H2O2 or a high concentration of AcOEt appears to have this effect. Full article
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35 pages, 1776 KiB  
Review
Marine Microorganism Molecules as Potential Anti-Inflammatory Therapeutics
by Malia Lasalo, Thierry Jauffrais, Philippe Georgel and Mariko Matsui
Mar. Drugs 2024, 22(9), 405; https://doi.org/10.3390/md22090405 - 3 Sep 2024
Viewed by 257
Abstract
The marine environment represents a formidable source of biodiversity, is still largely unexplored, and has high pharmacological potential. Indeed, several bioactive marine natural products (MNPs), including immunomodulators, have been identified in the past decades. Here, we review how this reservoir of bioactive molecules [...] Read more.
The marine environment represents a formidable source of biodiversity, is still largely unexplored, and has high pharmacological potential. Indeed, several bioactive marine natural products (MNPs), including immunomodulators, have been identified in the past decades. Here, we review how this reservoir of bioactive molecules could be mobilized to develop novel anti-inflammatory compounds specially produced by or derived from marine microorganisms. After a detailed description of the MNPs exerting immunomodulatory potential and their biological target, we will briefly discuss the challenges associated with discovering anti-inflammatory compounds from marine microorganisms. Full article
(This article belongs to the Special Issue Pharmacological Potential of Marine Natural Products)
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16 pages, 3145 KiB  
Article
Light Spectra, a Promising Tool to Modulate Ulva lacinulata Productivity and Composition
by Helena M. Amaro, Fernando Pagels, Rosa Melo, Antoine Fort, Ronan Sulpice, Graciliana Lopes, Isabel Costa and Isabel Sousa-Pinto
Mar. Drugs 2024, 22(9), 404; https://doi.org/10.3390/md22090404 - 3 Sep 2024
Viewed by 190
Abstract
Light quality is a key factor affecting algal growth and biomass composition, particularly pigments such as carotenoids, known for their antioxidant properties. Light-emitting diodes (LEDs) are becoming a cost-effective solution for indoor seaweed production when compared to fluorescent bulbs, allowing full control of [...] Read more.
Light quality is a key factor affecting algal growth and biomass composition, particularly pigments such as carotenoids, known for their antioxidant properties. Light-emitting diodes (LEDs) are becoming a cost-effective solution for indoor seaweed production when compared to fluorescent bulbs, allowing full control of the light spectra. However, knowledge of its effects on Ulva biomass production is still scarce. In this study, we investigated the effects of LEDs on the phenotype of an Ulva lacinulata strain, collected on the Northern Portuguese coast. Effects of white (W), green (G), red (R), and blue (B) LEDs were evaluated for growth (fresh weight and area), photosynthetic activity, sporulation, and content of pigments and antioxidant compounds. The results showed that there were no significant differences in terms of fresh weight accumulation and reduced sporulation among the tested LEDs, while W light induced the highest expansion rate. Under G, U. lacinulata attained a quicker photoacclimation, and the highest content of pigments and total antioxidant activity; but with R and W, antioxidant compounds against the specific radicals O2•− and NO were produced in a higher content when compared to other LEDs. Altogether, this study demonstrated that it is possible to modulate the bioactive properties of U. lacinulata by using W, R, and G light, opening the path to the production of biomass tailored for specific nutraceutical applications. Full article
(This article belongs to the Special Issue Biotechnology of Algae)
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11 pages, 2819 KiB  
Article
New Sesquiterpenoids from the Mangrove-Derived Fungus Talaromyces sp. as Modulators of Nuclear Receptors
by Tanwei Gu, Jian Cai, Danni Xie, Jianglian She, Yonghong Liu, Xuefeng Zhou and Lan Tang
Mar. Drugs 2024, 22(9), 403; https://doi.org/10.3390/md22090403 - 3 Sep 2024
Viewed by 234
Abstract
Four new sesquiterpenoids, talaroterpenes A–D (14), were isolated from the mangrove-derived fungus Talaromyces sp. SCSIO 41412. The structures of compounds 14 were elucidated through comprehensive NMR and MS spectroscopic analyses. The absolute configurations of 14 [...] Read more.
Four new sesquiterpenoids, talaroterpenes A–D (14), were isolated from the mangrove-derived fungus Talaromyces sp. SCSIO 41412. The structures of compounds 14 were elucidated through comprehensive NMR and MS spectroscopic analyses. The absolute configurations of 14 were assigned based on single-crystal X-ray diffraction and calculated electronic circular dichroism analysis. Talaroterpenes A–D (14) were evaluated with their regulatory activities on nuclear receptors in HepG2 cells. Under the concentrations of 200 μM, 1, 3 and 4 exhibited varying degrees of activation on ABCA1 and PPARα, while 4 showed the strongest activities. Furthermore, 4 induced significant alterations in the expression of downstream target genes CLOCK and BMAL1 of RORα, and the in silico molecular docking analysis supported the direct binding interactions of 4 with RORα protein. This study revealed that talaroterpene D (4) was a new potential non-toxic modulator of nuclear receptors. Full article
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48 pages, 5981 KiB  
Review
An Overview of Secondary Metabolites from Soft Corals of the Genus Capnella over the Five Decades: Chemical Structures, Pharmacological Activities, NMR Data, and Chemical Synthesis
by Can-Qi Liu, Qi-Bin Yang, Ling Zhang and Lin-Fu Liang
Mar. Drugs 2024, 22(9), 402; https://doi.org/10.3390/md22090402 - 2 Sep 2024
Viewed by 341
Abstract
There has been no specific review on the secondary metabolites from soft corals of the genus Capnella till now. In this work, all secondary metabolites from different species of the title genus were described. It covered the first work from 1974 to May [...] Read more.
There has been no specific review on the secondary metabolites from soft corals of the genus Capnella till now. In this work, all secondary metabolites from different species of the title genus were described. It covered the first work from 1974 to May 2024, spanning five decades. In the viewpoint of the general structural features, these chemical constituents were classified into four groups: sesquiterpenes, diterpenes, steroids, and lipids. Additionally, the 1H and 13C NMR data of these metabolites were provided when available in the literature. Among them, sesquiterpenes were the most abundant chemical compositions from soft corals of the genus Capnella. A variety of pharmacological activities of these compounds were evaluated, such as cytotoxic, antibacterial, antifungal, and anti-inflammatory activities. In addition, the chemical synthesis works of several representative sesquiterpenes were provided. This review aims to provide an up-to-date knowledge of the chemical structures, pharmacological activities, and chemical synthesis of the chemical constituents from soft corals of the genus Capnella. Full article
(This article belongs to the Special Issue Bioactive Compounds from Soft Corals and Their Derived Microorganisms)
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13 pages, 3073 KiB  
Article
Anti-Inflammatory Effect of Fucoidan from Costaria costata Inhibited Lipopolysaccharide-Induced Inflammation in Mice
by Wei Zhang, Peter C. W. Lee and Jun-O Jin
Mar. Drugs 2024, 22(9), 401; https://doi.org/10.3390/md22090401 - 2 Sep 2024
Viewed by 269
Abstract
Seaweed extracts, especially fucoidan, are well known for their immune-modulating abilities. In this current study, we extracted fucoidan from Costaria costata, a seaweed commonly found in coastal Asia, and examined its anti-inflammatory effect. Fucoidan was extracted from dried C. costata (FCC) using [...] Read more.
Seaweed extracts, especially fucoidan, are well known for their immune-modulating abilities. In this current study, we extracted fucoidan from Costaria costata, a seaweed commonly found in coastal Asia, and examined its anti-inflammatory effect. Fucoidan was extracted from dried C. costata (FCC) using an alcohol extraction method at an extraction rate of 4.5 ± 0.21%. The extracted FCC comprised the highest proportion of carbohydrates, along with sulfate and uronic acid. The immune regulatory effect of FCC was examined using bone marrow-derived dendritic cells (BMDCs). Pretreatment with FCC dose-dependently decreased the lipopolysaccharide (LPS)-induced upregulation of co-stimulatory molecules and major histocompatibility complex. In addition, FCC prevented morphological changes in LPS-induced BMDCs. Moreover, treatment of LPS-induced BMDCs with FCC suppressed the secretion of pro-inflammatory cytokines. In C57BL/6 mice, oral administration of FCC suppressed LPS-induced lung inflammation, reducing the secretion of pro-inflammatory cytokines in the bronchoalveolar lavage fluid. Finally, the administration of FCC suppressed LPS-induced sepsis. Therefore, FCC could be developed as a health supplement based on the observed anti-inflammatory effects. Full article
(This article belongs to the Special Issue Polysaccharides from Marine Environment)
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