Marine cyanobacteria - a rich source of natural substances (2023)

The potential of some soil cyanobacteria to influence plant development through the release of biologically active substances has been extensively characterized. Strategies for this include the use of culture supernatants from cyanobacteria, as these contain compounds that can affect plant development. However, there is little information on how the remaining nutrients from the culture medium used can contribute to the effect observed in the treated plants. In the present work,Tricormussp., a native Chilean cyanobacterium isolated from arid regions, the supernatants of which enhanced cumulative germination, shoot and root growth of the native grassPolypogon australis, was chosen. The observed effects were significant compared to water as a control, but were not significantly different when BG-11 broth was used as a control. The nutritional content ofTricormussp. Supernatants were characterized during the growth phases of the culture on BG-11 medium and showed a marked decrease in P (100%) and Mn content (84%) after the late exponential phase. Based on these results, a P- and Mn-free BG-11 medium (BG-11M) was prepared. In a bioassay withP. australisThe BG-11M effect was compared withTricormussp. Supernatants containing 40% P and 46% Mn compared to the original BG-11 medium. The results showed that BG-11M was less effective in promoting shoot growthP. australisthan the supernatants, suggesting that both elements, P and Mn, play a role in the development ofP. australis. We emphasize the need to consider the composition of the nutrients remaining on the culture medium when evaluating the effects of cyanobacterial cultures on plant growth and development.

To advance the development of green wastewater biotreatments, an in-depth analysis of algal-fungal interactions and high-quality biomass production is required, as the interactions in these cultures are complex. Microalgae can release a remarkable array of extracellular metabolites, ranging from alkaloids to fatty acids to abundant amino acids and peptides. These metabolites are associated with algicidal, antiprotozoal, insecticidal/larvicidal and antimicrobial activity. Acylhomoserine lactones (AHLs) can regulate the algae-fungi relationship, as they are signaling molecules that significantly influence the metabolism and growth of algae based on the organic matter in their environment. Fungi can use both organic and inorganic nitrogen (N), but are not as efficient as algae; For this reason, the algal-fungal co-culture is better able to remove N from the wastewater than the algal monoculture. Furthermore, the sponge's phosphorus removal capacity is comparable to or even better than algae. Symbiotic algae-fungi systems have a high ability to purify biogas through the use of photosynthesis. In addition, several value-adding substances can be obtained from the biomass of the co-culture, including fatty acids, polysaccharides, triglycerides, pigments and vitamins, which are used as specialty chemicals and bulk goods in various industrial sectors. Fungi can also act as flocculation agents in a way that is harmless to algal biomass, allowing reuse of the culture medium and easier harvesting, further reducing overall costs. Significant increases in biomass and lipid production have been observed in co-cultured algal sponge pellets compared to monoculture. This review aims to discuss hotspots in metabolic research in microalgal-fungal consortia, discuss quorum sensing in these cultures, and describe pioneering applications in wastewater treatment and biomass production technologies. Future prospects for microalgal-fungal consortia in wastewater treatment are also suggested. The results of this review would provide a reference for current research on algal-fungal mechanisms and further large-scale harvesting.

fresh seaweed,Alaria esculentaAndAscophyllum nodosum,are brown macroalgae species that are considered an excellent source of macro- and micronutrients. It is important to provide new approaches to ensure the microbiological safety of this product to ensure the preservation of nutritional values. In this study, these two species were treated with high pressure as well as traditional preservation methods (dry salt and hot water blanching), followed by a storage process to assess the influence of the microbiological content, and the microbiota profile was investigated after different treatments. High pressure treatments were introduced to avoid salt addition or loss of nutrients associated with traditional algae preservation methods. In general, fresh algae treated at high pressure (500 MPa) still have acceptable total viability values ​​of about 3 log CFU/mL after 30 days when stored at 4°C. 16S rDNA profiling revealed an average of 3059 operational taxonomic units (OTUs) for all algae analyzed. The four dominant phyla were Cyanobacteria, Proteobacteria, Firmicutes and Bacteroidota. Cyanobacteria dominated the bacterial communitiesA. esculentasamples, while Proteobacteria were predominantA. nodosumRehearse. In this study, HPP did not cause significant variation in microbiome profile diversity, but did change the relative abundance of different phyla, including Cyanobacteria, Fermicutes, Bacteriodota and Verrucomicrobia.

Although there are many ways to use microalgae as antimicrobial agents, little has been done to advance them beyond the characterization phase to the biotechnology phase. A challenge in screening microalgae for antimicrobial activity is their ability to synthesize biologically active secondary metabolites in response to environmental triggers. A rigorous scientific approach is needed to identify potential strains with good antimicrobial activity and promote the development of microalgae as antimicrobial agents. Microalgae are most commonly tested for antimicrobial activity using the disk diffusion test. However, this test is problematic and leads to false positive and false negative results. Quantitative minimum inhibitory concentration (MIC) values ​​determined in assays such as the microdilution broth assay are more reproducible and allow comparison of results between research groups. A dataset of published MIC values ​​for microalgae was compiled for this overview. The cyanobacteria and chlorophyta were most strongly represented, other phyla were underrepresented. These data were used to evaluate factors influencing antimicrobial activity, including test microorganisms, microalgal taxonomy, different extraction solvents, and the growth phase at harvest. Activity was considered good when MIC values ​​were below 1 mg/mL, moderate when MIC values ​​were 1–8 mg/mL, and poor when MIC values ​​were above 8.0 mg/mL. Areas requiring more research will be discussed, including screening a greater diversity of species in appropriate assays, reporting negative results, testing culture supernatant for activity, synergistic effects, and identification of antimicrobial compounds in chlorophyta. The potential for successful development and commercialization of antimicrobial microalgae will increase as more microalgae are studied and compounds are identified.

The ocean is a vast ecosystem that has remained largely unused and unexploited, giving birth to numerous organisms. As a result, marine organisms have attracted the interest of scientists as a rich source of natural resources with unique structural features and exciting biological activities. Marine Macrolide is a premium natural product with a highly oxygenated polyene backbone containing macrocyclic lactone. In recent decades, considerable effort has been made to isolate and characterize the chemical and biological properties of macrolides. Numerous macrolides are derived from various marine organisms such as marine microorganisms, fungi, zooplankton, molluscs, cnidarians, red algae, marsupials and bryozoans. In particular, the most important sources of macrolides are fungi, dinoflagellates and fungi. Marine macrolides have several bioactive properties such as antimicrobial (antibacterial, antifungal, antimalarial, antiviral), anti-inflammatory, antidiabetic, cytotoxic and neuroprotective effects. In short, marine organisms are abundant in naturally occurring macrolides, which can become the source of effective and efficient therapies for many diseases. This recent review summarizes these exciting and promising new marine macrolides in terms of biological activities and potential therapeutic applications.

Cyanobacteria are considered a factory for value-added substances. However, knowledge of the many interesting compounds that can be obtained from these prokaryotic organisms is still very limited. Nuclear magnetic resonance (NMR) spectroscopy is a widely used metabolic profiling technique that provides an overview of the most important metabolites in complex biological matrices. In this work high resoln¹H NMR was used to study the metabolic composition of freshwater cyanobacteriaFrom the bogs. This species showed high longevity and could grow for more than a hundred days without medium supplementation. Several interesting metabolites were detected during the study period, including several sugars and oligosaccharides, lipids (z.B., glycolipids, ω-3 and ω-6 fatty acids), amino acids, including mycosporin-like, peptides and pigments (z.B., ChlorophyllINand carotenoids). Thanks to the long-term monitoring implemented in this study, the production of these compounds can be linked to specific growth momentsnumber of fliesThis provides new insight into the most suitable harvest times for biotechnological use of certain molecules.

Antiviral Research, bind 112, 2014, s. 1-7

The cyanobacterial lectin scytovirin (SVN) binds with high affinity to high-mannose oligosaccharides on the envelope glycoprotein (GP) of a number of viruses and thereby blocks access to target cells. In this study, we investigated the ability of SVN to bind to Zaire ebola virus (ZEBOV) envelope GP and inhibit replication. SVN specifically interacted with the mucin-rich domain of the protein. In cell culture, it inhibited ZEBOV replication at a virus inhibitory concentration of 50% (EC₅₀) at 50 nM and was also active against the Angola strain of the related Marburg virus (MARV) with a similar EC₅₀. Injected subcutaneously into mice, SVN reached a peak plasma level of 100 nM in 45 min but was cleared within 4 h. When ZEBOV-infected mice received SVN by subcutaneous injection at 30 mg/kg/day every 6 hours starting the day before virus challenge, 9 out of 10 animals survived the infection, whereas all infected, untreated mice died. When treatment started one hour or one day after challenge, 70-90% of the mice survived. Quantification of infectious virus and viral RNA in serum, liver, and spleen samples taken on days 2 and 5 post-infection showed a trend toward lower titers in treated mice than in control mice, with a significant decrease in liver titers on the second day. Our findings provide further evidence for the potential of natural lectins as therapeutic agents in viral infections.

Bioorganic & Medicinal Chemistry, Band 22, Ausgabe 24, 2014, S. 6789-6795

Marine benthic cyanobacteria are well known as a source of toxic and potentially beneficial compounds. These microorganisms have been studied at many Caribbean sites, including recently sites in the Colombian Caribbean Sea. In this study, six lipopeptides named Almiramide D to H along with the well-known Almiramide B are identified from a mat labeled asOscillatoria nigroviridiscollected on Providence Island (Colombia, southwestern Caribbean Sea). The most abundant compounds, almiramides B and D, were characterized by NMR and HRESIMS, while the structures of the minor compounds, almiramides E to H, were suggested by analysis of their HRESIMS and MS²spectra. Almiramide B and D were tested against six human cell lines, including a gingival fibroblast cell line and five human tumor cell lines (A549, MDA-MB231, MCF-7, HeLa and PC3), which showed potent but non-selective toxicity.

Phytochemie, Band 122, 2016, S. 113-118

Bioassay-guided fractionation of two marine cyanobacterial extracts using human lung cancer cell line H-460 and human ovarian cancer cell line OVC-5 led to the isolation of three related α-methoxy-B,B′-dimethyl-γ-pyrones, each containing a modified alkyl chain, one of which has been identified as the previously described calcipyrone and designated calcipyrone A. The other compound was an analog named calcipyrone B. The third compound was identified as the recently reported yoshinone A. also isolated from a marine cyanobacterium. Calcipyrone A and B were obtained from a field collection of cyanobacteriaLeptolyngbyasp. from Fagasa Bay, American Samoa, while Yoshinon A was isolated from a field collection of cyanobacteria (cf.Schizotrixsp.) from Panama. One-dimensional and two-dimensional NMR experiments were used to determine the overall structures and relative configurations of the calkypyrones, and the absolute configuration of calkypyrone B was determined¹H NMR Analysis of Diastereomeric Mosher Esters. Calcipyrone A showed good cytotoxicity against H-460 human lung cancer cells (EC₅₀= 0.9 μM), while calkipyrone B and yoshinone A were less active (EC₅₀=9.0μM or >10μM). Both Kalkipyrone A and B showed moderate toxicitySaccharomyces cerevisiaeABC16-Monster-Stamm (IC₅₀= 14.6 and 13.4 μM, respectively), whereas Yoshinon A showed low toxicity to this yeast strain (IC₅₀=63,8μM).

Biocatalysis and Agricultural Biotechnology, bind 16, 2018, side 237-242

Phycocyanin is a blue-colored, naturally occurring phycobiliprotein pigment that is abundant in cyanobacteria, a blue-green algae. In this study, phycocyanin was derived fromGeitlerinemasp. TRV57. The extracted pigment was analyzed for its antioxidant properties using various methods, e.g. B. Phosphomolybdenum test, iron ion reduction performance test, DPPH radical scavenging activity, hydrogen peroxide radical scavenging test and anti-lipid peroxidation activity. These tests showed significant antioxidant activity of phycocyanin. At a concentration of 200 µg/ml, phycocyanin showed a maximum absorbance of 0.49 in the phosphomolybdenum assay, an absorbance of 0.85 in the ferric ion reduction test, 78.75% of DPPH scavenging activity, and 95.27% of H.₂Ö₂cleanup activity. IC₅₀A phycocyanin value of 185 µg/ml was determined for the anti-lipid peroxidation test. The study shows that the phycocyanin pigments have antioxidant properties and can be used as a promising pharmaceutical and nutraceutical compound.

International Journal of Biological Macromolecules, Bånd 102, 2017, S. 475-496

Lectins are ubiquitous proteins/glycoproteins of non-immune origin that bind reversibly to carbohydrates in a non-covalent and highly specific manner. These lectin-glycan interactions could be exploited to establish new therapeutic agents that target the adherence stage of viruses and thus help eliminate widespread viral infections. Here, the review focuses on hemagglutination activity, carbohydrate specificity and properties of cyanobacterial lectins. Cyanobacterial lectins, which exhibit high specificity towards mannose or complex glycans, may play a role as antiviral agents. The possible role of cyanobacterial lectins in combating various diseases of global concern, such as HIV, hepatitis, herpes, influenza and Ebola virus, has been widely discussed. The review also focuses on recent studies dealing with the structural analysis of glycan-lectin interactions, which in turn influence their mechanism of action. Overall, the promising approach of these cyanobacterial lectins provides insight into their use as antiviral agents.

Biotechnological production of bioactive compounds, 2020, pp. 221-259

As the main components of phytoplankton, microalgae and cyanobacteria are central to the global food chain and essential for the maintenance of Earth's ecosystems. Due to their adaptability to different cell culture conditions, algae are extremely versatile and therefore produce a wide range of valuable bioactive compounds. In recent decades, attention has increasingly been paid to the possibilities of commercial algae cultivation. Bioactive algal compounds include antioxidants (polyphenols, tocopherols, vitamin C, mycosporin-like amino acids), peptides (cyclic and acyclic), polyunsaturated fatty acids (PUFA) (e.g. docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)) e.g. β-glucan) and pigments such as carotenoids (carotene xanthophyll), chlorophylls and phycobilins (phycocyanin, phycoerythrin), etc. showed antibacterial, antiviral, antifungal, antioxidant, anti-inflammatory and antitumor properties. New cultivation and extraction techniques are effective in cultivating algal biomass and converting it into extracts of biologically active compounds without degradation. This chapter provides an overview of the biologically active compounds derived from algal biomass and their potential role in human well-being in a structured manner.