RESUMEN
The novelty of this study lies in demonstrating a new approach to control wilt diseases using Jania ethyl acetate extract. In the current investigation, the potential impacts of Jania sp. ethyl acetate extract (JE) on Tomato Fusarium oxysporum wilt (FOW) have been studied. The in vitro antifungal potential of JE against F. oxysporum (FO) was examined. GC-MS investigation of the JE revealed that, the compounds possessing fungicidal action were Phenol,2-methoxy-4-(2-propenyl)-,acetate, Eugenol, Caryophyllene oxide, Isoespintanol, Cadinene, Caryophylla-4(12),8(13)-dien-5à-ol and Copaen. Jania sp. ethyl acetate extract exhibited strong antifungal potential against FO, achieving a 20 mmzone of inhibition. In the experiment, two different methods were applied: soil irrigation (SI) and foliar application (FS) of JE. The results showed that both treatments reduced disease index present DIP by 20.83% and 33.33% respectively. The findings indicated that during FOW, proline, phenolics, and the antioxidant enzymes activity increased, while growth and photosynthetic pigments decreased. The morphological features, photosynthetic pigments, total phenol content, and antioxidant enzyme activity of infected plants improved when JE was applied through soil or foliar methods. It is interesting to note that the application of JE had a substantially less negative effect on the isozymes peroxidase and polyphenol oxidase in tomato plants, compared to FOW. These reactions differed depending on whether JE was applied foliarly or via the soil. Finally, the use of Jania sp. could be utilized commercially as an ecologically acceptable method to protect tomato plants against FOW.
Asunto(s)
Fusarium , Enfermedades de las Plantas , Solanum lycopersicum , Solanum lycopersicum/microbiología , Solanum lycopersicum/inmunología , Solanum lycopersicum/efectos de los fármacos , Fusarium/patogenicidad , Fusarium/efectos de los fármacos , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/prevención & control , Algas Marinas , Inmunidad de la Planta/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Rhodophyta , Antifúngicos/farmacologíaRESUMEN
The present study focused on the physiological and biochemical aspects of Tricleocarpa fragilis, red seaweed belonging to the phylum Rhodophyta, along the South Andaman coast, with particular attention given to its symbiotic relationships with associated flora and fauna. The physicochemical parameters of the seawater at the sampling station, such as its temperature, pH, and salinity, were meticulously analyzed to determine the optimal harvesting period for T. fragilis. Seaweeds attach to rocks, dead corals, and shells in shallow areas exposed to moderate wave action because of its habitat preferences. Temporal variations in biomass production were estimated, revealing the highest peak in March, which was correlated with optimal seawater conditions, including a temperature of 34 ± 1.1 °C, a pH of 8 ± 0.1, and a salinity of 32 ± 0.8 psu. GCâMS analysis revealed n-hexadecanoic acid as the dominant compound among the 36 peaks, with major bioactive compounds identified as fatty acids, diterpenes, phenolic compounds, and hydrocarbons. This research not only enhances our understanding of ecological dynamics but also provides valuable insights into the intricate biochemical processes of T. fragilis. The established antimicrobial potential and characterization of bioactive compounds from T. fragilis lay a foundation for possible applications in the pharmaceutical industry and other industries.
Asunto(s)
Rhodophyta , Algas Marinas , Rhodophyta/fisiología , Rhodophyta/metabolismo , Algas Marinas/fisiología , Algas Marinas/metabolismo , Agua de Mar/química , Ecosistema , Biomasa , Ácidos Grasos/metabolismo , Simbiosis/fisiología , AnimalesRESUMEN
The system of polysaccharides from Schizymenia dubyi (Nemastomatales) was investigated. It contains a mixture of hybrid dl galactans (SH-S) and carrageenan-like polysaccharides, which were separated by means of precipitation with KCl at high concentrations. The structural features of the carrageenan-like fraction (SH-I) were investigated by methylation analysis, desulfation, uronic acid reduction, and NMR spectroscopy. It was concluded that the structure has the typical alternance α-(1 â 3), ß-(1 â 4) of d-galactose units, with most of the 3-linked units sulfated in O-2 (and some in O-4), and most of the 4-linked units sulfated in O-3, and substituted in O-2 by single stubs of ß-d-glucuronic acid (partly sulfated in each of the three available positions). This substituent has been only seldom found in red seaweed galactans. Rheological studies of 5 % and 10 % w/v SH, SH-S and SH-I aqueous systems, either without ions, or in KCl or CaCl2 solution gave thickening behaviors. Their random coil conformations justify the pseudoplastic behavior observed in the viscosity versus shear rate curves. As SH-S and SH-I are both contained in SH, an interpenetrating network could form in SH between the glucurono-carrageenan and the agaran, as inferred from the mechanical spectra recorded in water, especially with potassium ion.
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Carragenina , Reología , Carragenina/química , Viscosidad , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Galactanos/química , Rhodophyta/química , Espectroscopía de Resonancia MagnéticaRESUMEN
Kainoid synthases are key enzymes in the biosynthesis of kainoids. Kainoids, as represented by DA and KA, are a class of naturally occurring non-protein amino acids with strong neurotransmitter activity in the mammalian central nervous system. Marine algae kainoid synthases include PnDabC from diatoms, which synthesizes domoic acid (DA), and DsKabC and GfKabC from red algae, which synthesize kainic acid (KA). Elucidation of the catalytic mechanism of kainoid synthases is of great significance for the rational design of better biocatalysts to promote the industrial production of kainoids for use in new drugs. Through modeling, molecular docking, and molecular dynamics simulations, we investigated the conformational dynamics of kainoid synthases. We found that the kainoid synthase complexes showed different stability in the simulation, and the binding and catalytic processes showed significant conformational transformations of kainoid synthase. The residues involved in specific interactions with the substrate contributed to the binding energy throughout the simulation process. Binding energy, the relaxed active pocket, electrostatic potential energy of the active pocket, the number and rotation of aromatic residues interacting with substrates during catalysis, and the number and frequency of hydrogen bonds between the individual functional groups revealed the structure-activity relationships and affected the degree of promiscuity of kainoid synthases. Our research enriches the understanding of the conformational dynamics of kainoid synthases and has potential guiding significance for their rational design.
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Diatomeas , Ácido Kaínico , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Relación Estructura-Actividad , Ácido Kaínico/análogos & derivados , Diatomeas/enzimología , Rhodophyta/enzimología , Oxo-Ácido-Liasas/química , Oxo-Ácido-Liasas/metabolismo , Enlace de HidrógenoRESUMEN
BACKGROUND: Pyropia yezoensis a commercially important red seaweed species, is susceptible to various microorganisms infections, among which bacterial infections are the most prominent ones. Pyropia yezoensis is often affected by harmful bacterial communities under high temperatures that can lead to its degradation and economic losses. The current study aimed to explore Pyropia yezoensis-associated microbiota and further identify potential isolates, which can degrade Pyropia yezoensis under high-temperature conditions. METHODS AND RESULTS: The 16S rRNA gene sequencing was used to identify the agarolytic bacterial species. The results showed that Chromohalobacter sp. strain AZ6, Pseudoalteromonas sp. strain AZ, Psychrobacter sp. strain AZ3, Vibrio sp. strain AZ, and Halomonas sp. strain AZ07 exhibited algicidal properties as these strains were more abundant at high temperature (25 °C). Among the five isolated strains, the potential isolate Halomonas sp. strain AZ07 showed high production of agarolytic enzymes, including lipase, protease, cellulase, and amylase. This study confirmed that the isolated strain could produce these four different enzymes. The strain Halomonas AZ07 was co-treated with Pyropia yezoensis cells under two different temperature environments, including 13 °C and 25 °C. The degradation of Pyropia yezoensis occurred at the optimum temperature of 25 °C and effectively degraded their cell wall, proteins, lipids, and carbohydrates. CONCLUSION: The successful cultivation of Pyropia yezoensis in coastal farm environments is dependent on specific temperature and environmental factors, and lower temperatures have been observed to be particularly beneficial for the survival and growth of Pyropia yezoensis. The temperature below 13 °C was confirmed to be the best niche for the symbiotic relationship of microbiota associated with Pyropia yezoensis for its growth, development, and production.
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Halomonas , ARN Ribosómico 16S , Halomonas/genética , Halomonas/metabolismo , Halomonas/enzimología , ARN Ribosómico 16S/genética , Calor , Rhodophyta/genética , Filogenia , Microbiota/genética , Algas Marinas/metabolismo , Algas Marinas/microbiología , Temperatura , Algas Comestibles , PorphyraRESUMEN
Biobased L-lactic acid (L-LA) appeals to industries; however, existing technologies are plagued by limited productivity and high energy consumption. This study established an integrated process for producing macroalgae-based L-LA from Eucheuma denticulatum phycocolloid (EDP). Dilute acid-assisted microbubbles-mediated ozonolysis (DAMMO) was selected for the ozonolysis of EDP to optimize D-galactose recovery. Through single-factor optimization of DAMMO treatment, a maximum D-galactose recovery efficiency (59.10 %) was achieved using 0.15 M H2SO4 at 80 °C for 75 min. Fermentation with 3 % (w/v) mixed microbial cells (Bacillus coagulans ATCC 7050 and Lactobacillus acidophilus-14) and fermented residues achieved a 97.67 % L-LA yield. Additionally, this culture approach was further evaluated in repeated-batch fermentation and showed an average L-LA yield of 93.30 %, providing a feasible concept for macroalgae-based L-LA production.
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Fermentación , Ácido Láctico , Ozono , Ozono/farmacología , Microburbujas , Algas Marinas/metabolismo , Galactosa/metabolismo , Bacillus coagulans , Lactobacillus acidophilus/metabolismo , Ácidos Sulfúricos/farmacología , Biotecnología/métodos , Algas Comestibles , RhodophytaRESUMEN
Copious amounts of methane, a major constituent of greenhouse gases currently driving climate change, are emitted by livestock, and efficient methods that curb such emissions are urgently needed to reduce global warming. When fed to cows, the red seaweed Asparagopsis taxiformis (AT) can reduce enteric methane emissions by up to 80%, but the achieved results can vary widely. Livestock produce methane as a byproduct of methanogenesis, which occurs during the breakdown of feed by microbes in the rumen. The ruminant microbiome is a diverse ecosystem comprising bacteria, protozoa, fungi, and archaea, and methanogenic archaea work synergistically with bacteria to produce methane. Here, we find that an effective reduction in methane emission by high-dose AT (0.5% dry matter intake) was associated with a reduction in methanol-utilizing Methanosphaera within the rumen, suggesting that they may play a greater role in methane formation than previously thought. However, a later spike in Methanosphaera suggested an acquired resistance, possibly via the reductive dehalogenation of bromoform. While we found that AT inhibition of methanogenesis indirectly impacted ruminal bacteria and fermentation pathways due to an increase in spared H2, we also found that an increase in butyrate synthesis was due to a direct effect of AT on butyrate-producing bacteria such as Butyrivibrio, Moryella, and Eubacterium. Together, our findings provide several novel insights into the impact of AT on both methane emissions and the microbiome, thereby elucidating additional pathways that may need to be targeted to maintain its inhibitory effects while preserving microbiome health and animal productivity. IMPORTANCE: Livestock emits copious quantities of methane, a major constituent of the greenhouse gases currently driving climate change. Methanogens within the bovine rumen produce methane during the breakdown of feed. While the red seaweed Asparagopsis taxiformis (AT) can significantly reduce methane emissions when fed to cows, its effects appear short-lived. This study revealed that the effective reduction of methane emissions by AT was accompanied by the near-total elimination of methane-generating Methanosphaera. However, Methanosphaera populations subsequently rebounded due to their ability to inactivate bromoform, a major inhibitor of methane formation found in AT. This study presents novel findings on the contribution of Methanosphaera to ruminal methanogenesis, the mode of action of AT, and the possibility for complementing different strategies to effectively curb methane emissions.
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Metano , Rumen , Animales , Metano/metabolismo , Bovinos , Rumen/microbiología , Bacterias/clasificación , Bacterias/metabolismo , Bacterias/genética , Microbioma Gastrointestinal , Microbiota , Archaea/metabolismo , Archaea/clasificación , Archaea/genética , Algas Marinas/metabolismo , Rhodophyta/metabolismo , Alimentación Animal/análisis , FermentaciónRESUMEN
Microalgae are a source of a wide variety of commodities, including particularly valuable pigments. The typical pigments present in microalgae are the chlorophylls, carotenoids, and phycobiliproteins. However, other types of pigments, of the family of water-soluble polyphenols, usually encountered in terrestrial plants, have been recently reported in microalgae. Among such microalgal polyphenols, many flavonoids have a yellowish hue, and are used as natural textile dyes. Besides being used as natural colorants, for example in the food or cosmetic industry, microalgal pigments also possess many bioactive properties, making them functional as nutraceutical or pharmaceutical agents. Each type of pigment, with its own chemical structure, fulfills particular biological functions. Considering both eukaryotes and prokaryotes, some species within the four most promising microalgae groups (Cyanobacteria, Rhodophyta, Chlorophyta and Heterokontophyta) are distinguished by their high contents of specific added-value pigments. To further enhance microalgae pigment contents during autotrophic cultivation, a review is made of the main related strategies adopted during the last decade, including light adjustments (quantity and quality, and the duration of the photoperiod cycle), and regard to mineral medium characteristics (salinity, nutrients concentrations, presence of inductive chemicals). In contrast to what is usually observed for growth-related pigments, accumulation of non-photosynthetic pigments (polyphenols and secondary carotenoids) requires particularly stressful conditions. Finally, pigment enrichment is also made possible with two new cutting-edge technologies, via the application of metallic nanoparticles or magnetic fields.
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Microalgas , Pigmentos Biológicos , Microalgas/metabolismo , Microalgas/química , Pigmentos Biológicos/química , Carotenoides/química , Carotenoides/metabolismo , Carotenoides/análisis , Ficobiliproteínas/química , Ficobiliproteínas/metabolismo , Cianobacterias/metabolismo , Cianobacterias/química , Rhodophyta/química , Rhodophyta/metabolismo , Chlorophyta/química , Chlorophyta/metabolismo , Clorofila/análisis , Polifenoles/análisis , Polifenoles/química , Polifenoles/metabolismo , Medios de Cultivo/químicaRESUMEN
Six previously undescribed meroterpenoids, penicianstinoids F-K (1-6), together with four known analogues, dehydroaustinol (7), dehydroaustin (8), penicianstinoid A (9), and furanoaustinol (10), were isolated from the cultures of the algicolous fungus Penicillium sp. RR-DL-1-7, derived from the red alga Rhodomela confervoides. Their structures and relative configuration were established by detailed spectroscopic analysis of NMR and HR-MS experiments, and the absolute configurations were assigned by X-ray diffraction and ECD spectral analysis. None of the isolates showed obvious growth inhibitory effects against five plankton and four bacteria species tested.
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Penicillium , Rhodophyta , Terpenos , Penicillium/química , Estructura Molecular , Terpenos/farmacología , Terpenos/aislamiento & purificación , Rhodophyta/química , China , Bacterias/efectos de los fármacosRESUMEN
A novel Gram-stain-negative, rod-shaped, non-spore-forming, aerobic, motile bacterium with a single polar or subpolar flagellum, designated strain H3510T, was isolated from marine alga collected on sea shore of Yantai, PR China. The organism grew optimally at 28 °C and pH 7.0 and in presence of 3.0â% (w/v) NaCl. The strain exhibited positive catalase activity but negative oxidase and nitrate reduction activities. The predominant cellular fatty acids were C18â:â1 ω7c and/or C18â:â1 ω6c, 11-methyl C18â:â1 ω7c, and C16â:â0. Additionally, the major polar lipids were phosphatidylglycerol, phosphatidylmonomethylethanolamine, diphosphatidylglycerol, and phosphatidylethanolamine; the respiratory quinone was ubiquinone 10 (Q-10). The genomic DNA G+C content of strain H3510T was 54.2%. The novel strain showed the closest relationship with Roseibium polysiphoniae KMM 9699T with 98.2â% 16S rRNA gene sequence similarity. The calculated values for average nucleotide identity and DNA-DNA hybridization between strain H3510T and the phylogenetically related Roseibium species were in the range of 71.3-74.9â% and 13.7-19.9â%, respectively. Based on polyphasic analyses, strain H3510T was identified as representing a novel species of the genus Roseibium, for which the name Roseibium algae sp. nov. is proposed. The type strain is H3510T (=KCTC 8206T=MCCC 1K04325T). The heterologously expressed inositol 2-dehydrogenase gene from strain H3510T displayed high oxidation activity on myo-inositol and showed potential in the production of rare stereoisomers of inositol, such as scyllo-inositol.
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Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S , Rhodobacteraceae , Análisis de Secuencia de ADN , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , China , Ácidos Grasos/química , Rhodobacteraceae/aislamiento & purificación , Rhodobacteraceae/clasificación , Rhodobacteraceae/genética , Ubiquinona/análogos & derivados , Agua de Mar/microbiología , Rhodophyta/microbiologíaRESUMEN
The formation of phytoene by condensing two geranylgeranyl diphosphate molecules catalyzed by phytoene synthase (PSY) is the first committed and rate-limiting step in carotenoid biosynthesis, which has been extensively investigated in bacteria, land plants and microalgae. However, this step in macroalgae remains unknown. In the present study, a gene encoding putative phytoene synthase was cloned from the economic red alga Pyropia yezoensis-a species that has long been used in food and pharmaceuticals. The conservative motifs/domains and the tertiary structure predicted using bioinformatic tools suggested that the cloned PyPSY should encode a phytoene synthase; this was empirically confirmed by pigment complementation in E. coli. This phytoene synthase was encoded by a single copy gene, whose expression was presumably regulated by many factors. The phylogenetic relationship of PSYs from different organisms suggested that red algae are probably the progeny of primary endosymbiosis and plastid donors of secondary endosymbiosis.
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Geranilgeranil-Difosfato Geranilgeraniltransferasa , Filogenia , Rhodophyta , Rhodophyta/genética , Rhodophyta/enzimología , Geranilgeranil-Difosfato Geranilgeraniltransferasa/genética , Geranilgeranil-Difosfato Geranilgeraniltransferasa/metabolismo , Carotenoides/metabolismo , Escherichia coli/genética , Clonación Molecular , Algas Comestibles , PorphyraRESUMEN
Seaweed polysaccharides are natural biomacromolecules with unique physicochemical properties (e.g., good gelling, emulsifying, and film-forming properties) and diverse biological activities (e.g., anticoagulant, antioxidant, immunoregulatory, and antitumor effects). Furthermore, they are nontoxic, biocompatible and biodegradable, and abundant in resources. Therefore, they have been widely utilized in food, cosmetics, and pharmaceutical industries. However, their properties and bioactivities sometimes are not satisfactory for some purposes. Modification of polysaccharides can impart the amphiphilicity and new functions to the biopolymers and change the structure and conformation, thus effectively improving their functional properties and biological activities so as to meet the requirement for targeted applications. This review outlined the modification methods of representative red algae polysaccharides (carrageenan and agar), brown algae polysaccharides (fucoidan, alginate, and laminaran), and green algae polysaccharides (ulvan) that have potential food applications, including etherification, esterification, degradation, sulfation, phosphorylation, selenylation, and so on. The improved functional properties and bioactivities of the modified seaweed polysaccharides and their potential food applications are also summarized.
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Polisacáridos , Algas Marinas , Algas Marinas/química , Polisacáridos/química , Polisacáridos/farmacología , Rhodophyta/química , Carragenina/química , Phaeophyceae/química , Chlorophyta/químicaRESUMEN
R-phycoerythrin (R-PE) is the most abundant, naturally occurring phycobiliproteins found in red algae. The spectroscopic and structural properties of phycobiliproteins exhibit unique absorption characteristics with two significant absorption maxima at 498 and 565 nm, indicating two different chromophores of R-PE, phycourobilin and phycoerythrobilin respectively. This study aimed to clarify how the stability of R-PE purified from F. lumbricalis was affected by different purification strategies. Crude extracts were compared to R-PE purified by i) microfiltration, ii) ultrafiltration, and iii) multi-step ammonium sulphate precipitation followed by dialysis. The stability of the different R-PE preparations was evaluated with respect to pH (2, 4, 6, 7, 8, 10 and 12) and temperature (20, 40, 60, 80 and 100 °C). The absorbance spectra indicated higher stability of phycourobilin as compared to phycoerythrobilin for heat and pH stability in the samples. All preparations of R-PE showed heat stability till 40 °C from the findings of color, concentration of R-PE and fluorescence emission. The crude extract showed stability from pH 6 to 8, whereas R-PE purified by ultrafiltration and multi-step ammonium sulphate precipitation were both stable from pH 4 to 8 and R-PE purified by microfiltration exhibited stability from pH 4 to 10 from the results of color, SDS-PAGE, and concentration of R-PE. At pH 2, the color changed to violet whereas a yellow color was observed at pH 12 in the samples along with the precipitation of the protein.
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Ficoeritrina , Rhodophyta , Ficoeritrina/química , Ficoeritrina/aislamiento & purificación , Concentración de Iones de Hidrógeno , Rhodophyta/química , Ultrafiltración/métodos , Estabilidad Proteica , Precipitación Química , Sulfato de Amonio/química , Calor , TemperaturaRESUMEN
The mitogenome is an important tool for taxonomic and evolutionary investigation. Here, a few complete mitogenomes of red algae have been reported. We have reported the complete mitogenome sequences of Grateloupia cornea Okamura, 1913 (Rhodophyta, Halymeniales). The genome is 30,595 bp in circumference, and has a strongly biased [AT] = 66.9%. Like most other Grateloupia species, it has a group II intron in the cox1 gene. Maximum likelihood and maximum parsimony analyses showed that G. cornea is more closely related to G. asiatica. This shows that the group II intron in the cox1 ORF present in most species of Grateloupia was present in their common ancestor, and uniquely lost in G. asiatica. The seven Grateloupia species with known mitogenome sequences remain monophyletic, with the genus Polyopes as sister taxon. The complete mitochondrial genome data will be valuable for future research on comparative mitochondrial genome analysis, an extensive understanding of gene content and organization, evolution of the cox1 intron in Rhodophyta as well as phylogenetic analysis.
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Genoma Mitocondrial , Filogenia , Rhodophyta , Rhodophyta/genética , Rhodophyta/clasificación , Intrones/genética , Evolución MolecularRESUMEN
The decline in the function and mass of skeletal muscle during aging or other pathological conditions increases the incidence of aging-related secondary diseases, ultimately contributing to a decreased lifespan and quality of life. Much effort has been made to surmise the molecular mechanisms underlying muscle atrophy and develop tools for improving muscle function. Enhancing mitochondrial function is considered critical for increasing muscle function and health. This study is aimed at evaluating the effect of an aqueous extract of Gloiopeltis tenax (GTAE) on myogenesis and muscle atrophy caused by dexamethasone (DEX). The GTAE promoted myogenic differentiation, accompanied by an increase in peroxisome proliferator-activated receptor γ coactivator α (PGC-1α) expression and mitochondrial content in myoblast cell culture. In addition, the GTAE alleviated the DEX-mediated myotube atrophy that is attributable to the Akt-mediated inhibition of the Atrogin/MuRF1 pathway. Furthermore, an in vivo study using a DEX-induced muscle atrophy mouse model demonstrated the efficacy of GTAE in protecting muscles from atrophy and enhancing mitochondrial biogenesis and function, even under conditions of atrophy. Taken together, this study suggests that the GTAE shows propitious potential as a nutraceutical for enhancing muscle function and preventing muscle wasting.
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Dexametasona , Desarrollo de Músculos , Atrofia Muscular , Extractos Vegetales , Animales , Atrofia Muscular/inducido químicamente , Atrofia Muscular/metabolismo , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/patología , Dexametasona/efectos adversos , Dexametasona/farmacología , Desarrollo de Músculos/efectos de los fármacos , Ratones , Extractos Vegetales/farmacología , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Diferenciación Celular/efectos de los fármacos , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Línea Celular , Proteínas Musculares/metabolismo , Masculino , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patología , Ratones Endogámicos C57BL , Proteínas de Motivos Tripartitos/metabolismo , Proteínas de Motivos Tripartitos/genética , RhodophytaRESUMEN
Spores have crucial importance in the establishment and development of seaweed populations. When the spore release matches with the low tidal period, they experience an extreme variation in the environmental conditions including the temperature. In this study, we assess the photosynthetic responses and growth of haploid (tetraspores) and diploid (carpospores) spores of two Gigartinales species (Mazzaella laminarioides and Iridaea cordata) from sub-Antarctic populations when exposed to an increasing temperature. In the laboratory, freshly released spores were exposed to a temperature gradient (7 [control], 10, 15, and 20 °C) recreating the temperature increase experienced by these spores during typical spring tides. Germination and further growth of spores previously exposed to temperature treatments were assessed. Carpospores and tetraspores exhibited variation in their photosynthetic response (measured as effective quantum yield; ΦPSII) to temperature increase. In Mazzaella laminarioides, only carpospores exhibited a reduction in ΦPSII (by 7-24% at 15-20 °C), while both types of spores of Iridaea cordata were sensitive to temperature increase (12-24% of ΦPSII reduction at 10-20 °C). Spores previously exposed to temperature treatments and maintained at 7 °C and low PAR germinated and developed in germlings. In general, germlings originated from carpospores pre-treated at high temperatures showed higher growth rates. The different responses to temperature increase exhibited by haploid and diploid propagules of both species highlight their ecophysiological capacity to face high-temperature variation ensuring successful recruitment survival.
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Diploidia , Haploidia , Rhodophyta , Esporas , Temperatura , Rhodophyta/fisiología , Rhodophyta/genética , Esporas/fisiología , Fotosíntesis , Regiones AntárticasRESUMEN
A simple empirical method is described that allows the assignment of absolute configurations of natural products containing chiral vicinal bromochloro (VBC) units, including the bromochloro substituted isoprenyl units present in the structures of antiproliferative halomon (1a) and its halogen-swapped isomer iso-halomon (1b) from the red alga, Portieria hornemannii, and callophycols A (3) and B (4) from Callophycus serratus. The relative configurations of 3 and 4, published in 2007, were incomplete: C-16 was left unassigned. It is now shown that the additivity of molar rotations, [M]D (herein, abbreviated [M])âa consequence of van't Hoff's principle of optical superpositionâcould be used to deconvolute rotatory contributions, designated as [MX] and [MY] of the two remotely spaced chiral substructures within 3 and 4 using simple arithmetic. Input of proxy values, [M Y1] and [MY2], for the two different VBC units in two equations for [MX] and application of a "conditional test" returns the same value for [MX] only when a proxy with the correct configuration is included. It is revealed that 3 and 4 have opposite configurations at the C-16 stereocenter: 16S and 16R, respectively. Two important implications lie in these findings: 3 and 4 appear to qualify as paired-regioisomers, coupled through a putative dyotropic rearrangement (DR), and the biosyntheses of other Callophycus secondary metabolites, now numbering over 50, are tightly controlled by stereoelectronic considerations including neighboring group interactions of the DR. It now appears, counter to earlier suggestions, that the chirality of Callophycus secondary metabolites, despite their high chemodiversity, are surprisingly highly conserved. Enantiofacial halogenation additions to the CâC double bonds of precursor alkenes appear to direct the formation of the remaining stereocenters at both the halogenated benzoate-decalin core and the distal VBC of 3 and 4. A consistent hypothesis is proposed to account for macrolactonizations in other Callophycus natural products including bromophycolides A and B. The conditional test of molar rotations was applied in a different context to understand the chiroptical properties and trends observed in the highly iodinated meroditerpenes, iodocallophycols A-E, also from Callophycus sp., resulting in the revision of the configuration of callophycol E from (10R,14R) to (10S,14S).
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Productos Biológicos , Productos Biológicos/química , Estereoisomerismo , Estructura Molecular , Conformación Molecular , Rhodophyta/químicaRESUMEN
Lectins are proteins that bind specifically and reversibly to carbohydrates, and some of them have significant anti-tumor activities. Compared to those of lectins from land plants, there are far fewer studies on algal lectins, despite of the high biodiversity of algae. However, canonical strategies based on chromatographic feature-oriented screening cannot satisfy the requirement for algal lectin discovery. In this study, prospecting for novel OAAH family lectins throughout 358 genomes of red algae and cyanobacteria was conducted. Then 35 candidate lectins and 1843 of their simulated mutated forms were virtually screened based on predicted binding specificities to characteristic carbohydrates on cancer cells inferred by a deep learning model. A new lectin, named Siye, was discovered in Kappaphycus alvarezii genome and further verified on different cancer cells. Without causing agglutination of erythrocytes, Siye showed significant cytotoxicity to four human cancer cell lines (IC50 values ranging from 0.11 to 3.95 µg/mL), including breast adenocarcinoma HCC1937, lung carcinoma A549, liver cancer HepG2 and romyelocytic leukemia HL60. And the cytotoxicity was induced through promoting apoptosis by regulating the caspase and the p53 pathway within 24 h. This study testifies the feasibility and efficiency of the genome mining guided by evolutionary theory and artificial intelligence in the discovery of algal lectins.
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Antineoplásicos , Simulación por Computador , Rhodophyta , Humanos , Rhodophyta/química , Rhodophyta/genética , Antineoplásicos/farmacología , Antineoplásicos/química , Lectinas/farmacología , Lectinas/química , Lectinas/genética , Lectinas/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Genoma , Algas ComestiblesRESUMEN
In 2022, there were around 20 million new cases and over 9.7 million cancer-related deaths worldwide. An increasing number of metabolites with anticancer activity in algae had been isolated and identified, which were promising candidates for cancer therapy. Red algae are well-known for the production of brominated metabolites, including terpenoids and phenols, which have the capacity to induce cell toxicity. Some non-toxic biological macromolecules, including polysaccharides, are distinct secondary metabolites found in many algae, particularly green algae. They possess anticancer activities by inhibiting tumor angiogenesis, stimulating the immune response, and inducing apoptosis. However, the structure-activity relationship between these components and antitumor activity, as well as certain taxa within the algae, remains relatively unstudied. This work is based on the reports published from 2003 to 2024 in PubMed and ISI Web of Science databases. A comprehensive review of the characterized algal anticancer active compounds, together with their structure and mechanism of action was performed. Also, their structure-activity relationship was preliminarily summarized to better assess their potential properties as a natural, safe bioactive product to be used as an alternative for the treatment of cancers, leading to new opportunities for drug discovery.
Asunto(s)
Neoplasias , Humanos , Neoplasias/tratamiento farmacológico , Relación Estructura-Actividad , Rhodophyta/química , Chlorophyta/química , Antineoplásicos/farmacología , Antineoplásicos/química , Animales , Productos Biológicos/farmacología , Productos Biológicos/químicaRESUMEN
Production of the red seaweed Palmaria palmata is currently hindered by a lack of standardised cultivation methods leading to uncertainties in yield and product quality. This study assessed vegetative propagation of meristematic fragments and the protein content and bioactivity potential of resulting plants. Growth was strong and sustained, averaging 5% day-1. Total protein contents initially decreased but recovered as the fragments grew larger and thicker. Samples displayed the highest antioxidant activity early in the experiment, suggesting that wounds may increase the secretion of antioxidant compounds. In silico analysis identified 762 potentially bioactive motifs, including 70 matching in vitro results. The newly discovered peptide SLLYSDITRPGGNMYTTR (SR18), linked to the pigment allophycocyanin, had very strong antioxidant properties and may drive the recorded in vitro activity. Vegetative propagation appears as a strong potential cultivation tool, and the utilised approach can be applied to assess the cultivation and nutritional potential of other seaweed species.