Marine Drugs最新文献

Extraction of lipids and high-value products from highly wet microalgae requires significant energy for the drying pretreatment. In this study, we examined the direct extraction of lipids, β-carotene, and polyphenolic compounds from wet Dunaliella salina using liquefied dimethyl ether (DME), which is effective in lipid extraction for biofuel production. The amount of DME-extracted β-carotene was 7.0 mg/g, which was higher than that obtained from the chloroform-methanol extraction. Moreover, the total phenolic content extracted with DME and its antioxidant capacity were slightly higher than those extracted with chloroform-methanol. DME removed almost all the water and extracted 29.2 wt% of total lipids and 9.7 wt% of fatty acids. More lipids were extracted from wet samples by liquefied DME than by chloroform-methanol extraction. The C/N ratio of lipids extracted with DME was 112.0, higher than that of chloroform-methanol. The high C/N ratio suggests that nitrogen-containing phosphatidylcholines may be less easily extracted by liquefied DME and may be highly selective. However, the ratio of saturated fatty acids was 34.8%, lower than that of chloroform-methanol. Na⁺ and Mg²⁺ in the culture medium were not extracted using DME. Thus, using the extract with DME has both advantages and disadvantages compared to using the extract with chloroform-methanol; however, it has satisfactory extraction properties. DME is expected to be an environment-friendly alternative solvent because it does not require drying, which is necessary for conventional extraction solvents.

A cellular matrix derived from natural tissue functions as a highly biocompatible and versatile material for wound healing application. It provides a complex and highly organized environment with biological molecules and physical stimuli. Recently, various kinds of tissue/organ decellularized extracellular matrixes (dECMs) from bovine and porcine have been used as biomedical applications to support tissue regeneration but inherit religious restrictions and the risk of disease transmission to humans. Marine fish-derived dECMs are seen as attractive alternatives due to their similarity to mammalian physiology, reduced biological risks, and fewer religious restrictions. The aim of this study was to derive a decellularized matrix from the olive flounder (Paralichthys olivaceus) skin and evaluate its suitability as a wound healing application. Olive flounder skin was treated with a series of chemical treatments to remove cellular components. Decellularized fish skin (dFS) was confirmed to be successful in decellularization by evaluating the DNA content (2.84%). The dFS was characterized and evaluated in vivo to assess its biological activities. The mouse wound defect model was used to evaluate the in vivo performance of the dFS compared with that of the decellularized porcine skin (dPS). The resultant dFS was shown to enhance wound healing compared with the no-treatment group and dPS. This study suggests that dFS has potential for skin regeneration application.

Marine sponges are well-known for hosting rich microbial communities. Sponges are the most prolific source of marine bioactive compounds, which are frequently synthesized by their associated microbiota. Calyx nicaeensis is an endemic Mediterranean sponge with scarce information regarding its (bioactive) secondary metabolites. East Mediterranean specimens of mesophotic C. nicaeensis have never been studied. Moreover, no research has inspected its associated bacteria. Thus, we studied the sponge's bacterial diversity and examined bacterial interspecific interactions in search of a promising antibacterial candidate. Such novel antimicrobial agents are needed since extensive antibiotic use leads to bacterial drug resistance. Bacteria cultivation yielded 90 operational taxonomic units (OTUs). A competition assay enabled the testing of interspecific interactions between the cultured OTUs. The highest-ranked antagonistic bacterium, identified as Paenisporosarcina indica (previously never found in marine or cold habitats), was mass cultured, extracted, and separated using size exclusion and reversed-phase chromatographic methods, guided by antibacterial activity. A pure compound was isolated and identified as 3-oxy-anteiso-C₁₅-fatty acid-lichenysin. Five additional active compounds await final cleaning; however, they are lichenysins and surfactins. These are the first antibacterial compounds identified from either the C. nicaeensis sponge or P. indica bacterium. It also revealed that the genus Bacillus is not an exclusive producer of lichenysin and surfactin.

Since the 2005 discovery of the first enzyme capable of depolymerizing polyethylene terephthalate (PET), an aromatic polyester once thought to be enzymatically inert, extensive research has been undertaken to identify and engineer new biocatalysts for plastic degradation. This effort was directed toward developing efficient enzymatic recycling technologies that could overcome the limitations of mechanical and chemical methods. These enzymes are versatile molecules obtained from microorganisms living in various environments, including soil, compost, surface seawater, and extreme habitats such as hot springs, hydrothermal vents, deep-sea regions, and Antarctic seawater. Among various plastics, PET and polylactic acid (PLA) have been the primary focus of enzymatic depolymerization research, greatly enhancing our knowledge of enzymes that degrade these specific polymers. They often display unique catalytic properties that reflect their particular ecological niches. This review explores recent advancements in marine-derived enzymes that can depolymerize synthetic plastic polymers, emphasizing their structural and functional features that influence the efficiency of these catalysts in biorecycling processes. Current status and future perspectives of enzymatic plastic depolymerization are also discussed, with a focus on the underexplored marine enzymatic resources.

Collagen is a popular nutricosmetic ingredient in food supplements due to its anti-aging and other positive effects on the skin. Due to its widespread use and the lack of regulation in this area, appropriate quality control is required to ensure efficacy and safety, with the development of analytical methods playing an important role. Currently, the quantitative determination of collagen is mainly based on time-consuming derivatization-based spectroscopic methods or on complex chromatographic methods with mass spectrometric detection. Therefore, in this study, two new, simple chromatographic methods have been developed. One is intended for the analysis of untreated samples and is characterized by the speed and simplicity of sample preparation. The other method quantifies collagen via the underivatized tripeptide Gly-Pro-Hyp formed by bacterial collagenase hydrolysis and is characterized by its specificity and ability to distinguish between marine and terrestrial collagen. The latter is a novelty in the field of simple methods for collagen analysis and is particularly important in terms of safety. Our comparison with established analytical methods (e.g., via hydroxyproline after complete hydrolysis) for collagen analysis undoubtedly showed the superiority of these new methods for the routine quality control of collagen supplements in terms of specificity, repeatability, sample stability, and simplification in sample preparation. The collagen content in the supplements tested was found to be adequate; however, some discrepancies were found regarding the labeling and origin of the collagen, with possible safety implications.

Phycocyanin was extracted from Spirulina platensis using conventional extraction (CE), direct ultrasonic-assisted extraction (direct UAE), indirect ultrasonic-assisted extraction (indirect UAE), and microwave-assisted extraction (MAE) methods at different temperatures, extraction intervals, stirring rate, and power intensities while maintaining the same algae to solvent ratio (1:15 w/v). The optimization of the extraction parameters indicated that the direct UAE yielded the highest phycocyanin concentration (29.31 ± 0.33 mg/mL) and antioxidant activity (23.6 ± 0.56 mg TE/g algae), while MAE achieved the highest purity (Rp = 0.5 ± 0.002). Based on the R_P value, phycocyanin extract obtained by MAE (1:15 w/v algae to solvent ratio, 40 min, 40 °C, and 900 rpm) was selected as active compound in an alginate-based hydrogel formulation designed as potential wound dressings. Phycocyanin extracts and loaded hydrogels were characterized by FT-IR analysis. SEM analysis confirmed a porous structure for both blank and phycocyanin loaded hydrogels, while the mechanical properties remained approximately unchanged in the presence of phycocyanin. Phycocyanin release kinetics was investigated at two pH values using Zero-order, First-order, Higuchi, and Korsmeyer-Peppas kinetics models. The Higuchi model best fitted the experimental results. The R² value at higher pH was nearly 1, indicating a superior fit compared with lower pH values.

Inflammation is considered as one of the most primary protective innate immunity responses, closely related to the body's defense mechanism for responding to chemical, biological infections, or physical injuries. Furthermore, prolonged inflammation is undesirable, playing an important role in the development of various diseases, such as heart disease, diabetes, Alzheimer's disease, atherosclerosis, rheumatoid arthritis, and even certain cancers. Marine-derived fungi represent promising sources of structurally novel bioactive natural products, and have been a focus of research for the development of anti-inflammatory drugs. This review covers secondary metabolites with anti-inflammatory activities from marine-derived fungi, over the period spanning August 2018 to July 2024. A total of 285 anti-inflammatory metabolites, including 156 novel compounds and 11 with novel skeleton structures, are described. Their structures are categorized into five categories: terpenoids, polyketides, nitrogen-containing compounds, steroids, and other classes. The biological targets, as well as the in vitro and in vivo screening models, were surveyed and statistically summarized. This paper aims to offer valuable insights to researchers in the exploration of natural products and the discovery of anti-inflammatory drugs.

The incidence of Mycobacterium marinum infection is on the rise; however, the existing drug treatment cycle is lengthy and often requires multi-drug combination. Therefore, there is a need to develop new and effective anti-M. marinum drugs. Cochliomycin A, a 14-membered resorcylic acid lactone with an acetonide group at C-5' and C-6', exhibits a wide range of antimicrobial, antimalarial, and antifouling activities. To further explore the effect of this structural change at C-5' and C-6' on this compound's activity, we synthesized a series of compounds with a structure similar to that of cochliomycin A, bearing ketal groups at C-5' and C-6'. The R/S configuration of the diastereoisomer at C-13' was further determined through an NOE correlation analysis of CH₃ or CH₂ at the derivative C-13' position and the H-5' and H-6' by means of a 1D NOE experiment. Further comparative ¹H NMR analysis of diastereoisomers showed the difference in the chemical shift (δ) value of the diastereoisomers. The synthetic compounds were screened for their anti-microbial activities in vitro. Compounds 15-24 and 28-35 demonstrated promising activity against M. marinum, with MIC₉₀ values ranging from 70 to 90 μM, closely approaching the MIC₉₀ of isoniazid. The preliminary structure-activity relationships showed that the ketal groups with aromatic rings at C-5' and C-6' could enhance the inhibition of M. marinum. Further study demonstrated that compounds 23, 24, 29, and 30 had significant inhibitory effects on M. marinum and addictive effects with isoniazid and rifampicin. Its effective properties make it an important clue for future drug development toward combatting M. marinum resistance.

Seaweed polysaccharides are versatile both in their functions in seaweed physiology and in their practical applications in society. However, their content and quality vary greatly. This review discusses the main factors that influence the yield and quality of polysaccharides, specifically carrageenans and agars (sulfated galactans) found in red algae species (Rhodophyta). In addition, its historical, current, and emerging applications are also discussed. Carrageenan has been influenced mainly by photosynthetically active radiation (PAR) and nitrogen, while its relationship with temperature has not yet been replicated by recent studies. Agar's seasonal trend has also been found to be more ambiguous than stated before, with light, temperature, nutrients, and pH being influencing factors. In this review, it is also shown that, depending on the compound type, seaweed polysaccharides are influenced by very different key factors, which can be crucial in seaweed aquaculture to promote a high yield and quality of polysaccharides. Additionally, factors like the extraction method and storage of polysaccharides also influence the yield and quality of these compounds. This review also highlights the drawbacks and inadequacy inherent from the conventional (or current) extraction technology approaches.

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.