This study describes the taxonomic diversity of pigmented, agar-degrading bacteria isolated from the surface of macroalgae collected in King George Island, Antarctica. A total of 30 pigmented, agarolytic bacteria were isolated from the surface of the Antarctic macroalgae Adenocystis utricularis, Monostroma hariotii, Iridaea cordata, and Pantoneura plocamioides. Based on the 16S rRNA data, the agarolytic isolates were affiliated to the genera Algibacter, Arthrobacter, Brachybacterium, Cellulophaga, Citricoccus, Labedella, Microbacterium, Micrococcus, Salinibacterium, Sanguibacter, and Zobellia. Isolates phylogenetically related to Cellulophaga algicola showed the highest agarase activity in culture supernatants when tested at 4 and 37 °C. This is the first investigation of pigmented agar-degrading bacteria, members of microbial communities associated with Antarctic macroalgae, and the results suggest that they represent a potential source of cold-adapted agarases of possible biotechnological interest.

• MeSH
• Agar metabolism   MeSH
• Bacteria classification   genetics   isolation & purification   metabolism   MeSH
• Pigments, Biological analysis   MeSH
• DNA, Bacterial chemistry   genetics   MeSH
• Seaweed microbiology   MeSH
• DNA, Ribosomal chemistry   genetics   MeSH
• RNA, Ribosomal, 16S genetics   MeSH
• Sequence Analysis, DNA MeSH
• Temperature MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• Antarctic Regions MeSH
• Names of Substances
• Agar MeSH
• Pigments, Biological MeSH
• DNA, Bacterial MeSH
• DNA, Ribosomal MeSH
• RNA, Ribosomal, 16S MeSH

Marine organisms have gained considerable biotechnological interest in recent years due to their wide variety of bioactive compounds with potential applications. Mycosporine-like amino acids (MAAs) are UV-absorbing secondary metabolites with antioxidant and photoprotective capacity, mainly found in organisms living under stress conditions (e.g., cyanobacteria, red algae, or lichens). In this work, five MAAs were isolated from two red macroalgae (Pyropia columbina and Gelidium corneum) and one marine lichen (Lichina pygmaea) by high-performance countercurrent chromatography (HPCCC). The selected biphasic solvent system consisted of ethanol, acetonitrile, saturated ammonium sulphate solution, and water (1:1:0.5:1; v:v:v:v). The HPCCC process for P. columbina and G. corneum consisted of eight separation cycles (1 g and 200 mg of extract per cycle, respectively), whereas three cycles were performed for of L. pygmaea (1.2 g extract per cycle). The separation process resulted in fractions enriched with palythine (2.3 mg), asterina-330 (3.3 mg), shinorine (14.8 mg), porphyra-334 (203.5 mg) and mycosporine-serinol (46.6 mg), which were subsequently desalted by using precipitation with methanol and permeation on a Sephadex G-10 column. Target molecules were identified by HPLC, MS, and NMR.

• Keywords
• countercurrent chromatography, isolation, marine lichen, mycosporine-like amino acids, photoprotection, red macroalgae,
• MeSH
• Amino Acids chemistry   MeSH
• Lichens * chemistry   MeSH
• Seaweed * chemistry   MeSH
• Countercurrent Distribution MeSH
• Rhodophyta * chemistry   MeSH
• Plant Extracts metabolism   MeSH
• Ultraviolet Rays MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Amino Acids MeSH
• Plant Extracts MeSH

This study investigates the effects of the red macroalgae Galaxaura oblongata diet supplementation on roach (Rutilus rutilus) fingerlings growth and gene expression related to immunity, the intestinal barrier, and antioxidant status. Roach fingerlings (2.26 ± 0.04 g) were fed a basic diet supplemented with three different percentages of G. oblongata powder: 0.25 % (G1), 0.50 % (G2), and 1.0 % (G3) over 8 weeks, with a control group (C) receiving no supplementation. The study found that growth parameters significantly increased in the G1 and G2 groups compared to the C and G3 groups (P < 0.05). Immune responses, measured by total immunoglobulin (Ig) and lysozyme activity, showed a significant increase in the whole-body extract of the G2 group (P < 0.05) and the skin mucus of all treated groups compared to the control (P < 0.05). G. oblongata supplementation did not significantly affect catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities in the whole-body extract, although GPx activity in skin mucus was significantly higher in the supplemented groups. Additionally, the gene expression of interleukin 1-beta (il-1β), occludin, gpx and sod, but not Toll-like receptor increased in G. oblongata treated groups. These results suggest that G. oblongata can serve as a beneficial feed additive in the culture of roach fingerlings, enhancing growth and immune function.

• Keywords
• Antioxidant defense, Bioactive compounds, Gene expression, Immunity, Seaweeds, Tight junction proteins,
• MeSH
• Antioxidants metabolism   MeSH
• Cyprinidae * growth & development   metabolism   immunology   MeSH
• Diet veterinary   MeSH
• Animal Feed * analysis   MeSH
• Seaweed * chemistry   MeSH
• Oxidative Stress MeSH
• Dietary Supplements MeSH
• Rhodophyta * chemistry   MeSH
• Intestines growth & development   drug effects   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Antioxidants MeSH

The present study aims to focus on the bioprospecting of marine macroalgae of Turbinaria species, plenteous biomass of the world ocean. Three types of solvents, i.e., H2 O, MeOH/H2 O (80:20, v/v) and hexane/i-PrOH (50:50, v/v), were used for extraction. Both the biological activity and the pattern of present chemicals were characterized. For the cell proliferation assay, the human embryonic kidney 293 cells, cervix/breast/pancreatic adenocarcinoma, and osteosarcoma cells were used. For the antioxidant activity determination, both intracellular assay with human embryonic kidney and cervix adenocarcinoma cells, as well as the biochemical DPPH test, were employed. To complete the information about macroalgae composition, organic compounds were characterized by the liquid chromatography coupled with high resolution tandem mass spectrometry. Attention was concentrated mainly on the lipidomic profile characterization. In spite the fact that any significant antiproliferative effect was not observed for cancer cells, both the Turbinaria species were shown to be good protectors against the oxidative stress of the non-cancer cells. Most of the antioxidants were determined in the hexane/i-PrOH extract. As regards the lipids identified, most of them belonged to the triacylglycerols followed by sphingomyelins, diacylglycerols, and polar (lyso)phospholipids. Additionally to fatty acids with 14, 16 and 18 carbons, also those with odd carbon numbers were frequently present.

• Keywords
• Algae, Antioxidant activities, Antiproliferation assay, Bioprospecting, Liquid chromatography, Mass spectrometry, Turbinaria,
• MeSH
• Antioxidants pharmacology   MeSH
• Biological Products chemistry   MeSH
• Bioprospecting methods   MeSH
• Cells, Cultured MeSH
• Humans MeSH
• Lipids analysis   chemistry   MeSH
• Metabolome MeSH
• Metabolomics MeSH
• Microalgae chemistry   metabolism   MeSH
• Protective Agents pharmacology   MeSH
• Cell Proliferation drug effects   MeSH
• Tandem Mass Spectrometry MeSH
• Chromatography, High Pressure Liquid MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Antioxidants MeSH
• Biological Products MeSH
• Lipids MeSH
• Protective Agents MeSH

Edible seaweeds with a relatively high total arsenic concentration have been a global concern. As the largest seaweed producer, China contributes about 60 % of the global seaweed production. The present study investigated 20 seaweed species collected from representative seaweed farming sites in the six provinces along the Chinese coastline, of which Saccharina japonica, Undaria pinnatifida, Neopyropia spp., Gracilaria spp., Sargassum fusiforme were listed as the most consumed seaweeds in Food and Agriculture Organization of the United Nations (FAO). The inorganic arsenic (iAs) concentration in most of the seaweeds was below maximum limits (0.3 mg iAs/kg) as seaweed additives for infant food in the National Food Safety Standard of Pollutants in China (GB2762-2017, 2017), except for the species Sargassum, in which the iAs concentration significantly exceeded the limit and ranged from 15.1 to 83.7 mg/kg. Arsenic speciation in 4 cultivated seaweeds grown in both temperate and subtropical zones is reported for the first time. No significant differences in total As and iAs concentration were identified, except slightly higher total As concentration were found in Saccharina japonica growing in the temperate zone. The estimated daily intake (EDI) of toxic iAs via seaweed consumption was generally below the EFSA CONTAM Panel benchmark dose lower confidence limit (0.3 μg/kg bw/day) except for all Sargassum species where the EDI was significantly higher than 0.3 μg/kg bw/day. Moreover, the first-ever reported data on As speciation indicated very high iAs concentrations in Sargassum hemiphyllum and Sargassum henslowianum. To minimize the food chain iAs exposure, reducing both human intake of Sargassum spp. and the used of Sargassum spp. for animal feed is highly recommended. CAPSULE: This study showed that edible seaweed Sargassum spp. consumption may pose a health risk related to inorganic arsenic (iAs) exposure. The risk of iAs exposure via seaweed consumption or livestock is a concern that needs to be monitored. The arsenic accumulation and speciation may be predominantly species-dependent rather than environmental-dependent.

• Keywords
• Arsenic, Arsenic speciation, Edible seaweeds, Health risks, Macroalgae,
• MeSH
• Arsenic * analysis   MeSH
• Arsenicals * analysis   MeSH
• Food Contamination analysis   MeSH
• Laminaria * MeSH
• Environmental Pollutants * MeSH
• Humans MeSH
• Seaweed * MeSH
• Arsenic Poisoning * MeSH
• Sargassum * MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Arsenic * MeSH
• Arsenicals * MeSH
• Environmental Pollutants * MeSH

Marine macroalgae have a very high carbohydrate content due to complex algal polysaccharides (APS) like agar, alginate, and ulvan in their cell wall. Despite numerous reports on their biomedical properties, their hydrocolloid nature limits their applications. Algal oligosaccharides (AOS), which are hydrolyzed forms of complex APS, are gaining importance due to their low molecular weight, biocompatibility, bioactivities, safety, and solubility in water that makes it a lucrative alternative. The AOS produced through enzymatic hydrolysis using microbial enzymes have far-reaching applications because of its stereospecific nature. Identification and characterization of novel microorganisms producing APS hydrolyzing enzymes are the major bottlenecks for the efficient production of AOS. This review will discuss the marine microbial enzymes identified for AOS production and the bioactive potential of enzymatically produced AOS. This can improve our understanding of the biotechnological potential of microbial enzymes for the production of AOS and facilitate the sustainable utilization of algal biomass. Enzymatically produced AOS are shown to have bioactivities such as antioxidant, antiglycemic, prebiotic, immunomodulation, antiobesity or antihypercholesterolemia, anti-inflammatory, anticancer, and antimicrobial activity. The myriad of health benefits provided by the AOS is the need of the hour as there is an alarming increase in physiological disorders among a wide range of the global population.

• MeSH
• Alginates MeSH
• Seaweed * MeSH
• Oligosaccharides * MeSH
• Dietary Supplements MeSH
• Prebiotics MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• Alginates MeSH
• Oligosaccharides * MeSH
• Prebiotics MeSH

• MeSH
• Animal Feed MeSH
• International Educational Exchange MeSH
• Seaweed * MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• Czechoslovakia MeSH
• Uzbekistan MeSH

Eustigmatophyte algae represent an interesting model system for the study of the regulation of the excitation energy flow due to their use of violaxanthin both as a major light-harvesting pigment and as the basis of xanthophyll cycle. Fluorescence induction kinetics was studied in an oleaginous marine alga Nannochloropsis oceanica. Nonphotochemical fluorescence quenching was analyzed in detail with respect to the state of the cellular xanthophyll pool. Two components of nonphotochemical fluorescence quenching (NPQ), both dependent on the presence of zeaxanthin, were clearly resolved, denoted as slow and fast NPQ based on kinetics of their formation. The slow component was shown to be in direct proportion to the amount of zeaxanthin, while the fast NPQ component was transiently induced in the presence of membrane potential on subsecond timescales. The applicability of these observations to other eustigmatophyte species is demonstrated by measurements of other representatives of this algal group, both marine and freshwater.

• Keywords
• Chl a fluorescence, Eustigmatophyceae, Nannochloropsis, Nonphotochemical quenching, Xanthophyll cycle,
• MeSH
• Fluorescence MeSH
• Photosynthesis MeSH
• Seaweed chemistry   MeSH
• Publication type
• Journal Article MeSH

• MeSH
• Dilatation and Curettage adverse effects   MeSH
• Adult MeSH
• Humans MeSH
• Metrorrhagia surgery   MeSH
• Seaweed * MeSH
• Uterine Cervicitis etiology   therapy   MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Case Reports MeSH

Bioactive compounds such as karrikinolide (KAR1 from smoke) and eckol (from the seaweed Ecklonia maxima) show promising effects on several important crop plants. These plant growth-stimulating organic biomolecules, along with crude extracts (smoke-water and Kelpak® product prepared from Ecklonia maxima), were tested on spinach plants. Eckol sprayed at 10-6 M significantly increased all the growth and biochemical parameters examined compared to control spinach plants. All tested plant growth biostimulants significantly increased total chlorophyll, carotenoids and protein content of spinach leaves. The cytokinin profile of spinach plants was also determined. Cis-zeatin, dihydrozeatin and isopentenyladenine types of cytokinins were promoted by both smoke- and seaweed-based biostimulants. In comparison to the control plants, the level of free sinapic acid was greater in all spinach plants treated with these biostimulants. The application of these biostimulants can help spinach crop by improving growth, yield and nutritional quality; moreover, they are organic and cost-effective.

• Keywords
• Biostimulants, Growth, Leafy vegetables, Phytohormones, Seaweed, Smoke,
• MeSH
• Cytokinins metabolism   MeSH
• Dioxins isolation & purification   pharmacology   MeSH
• Furans isolation & purification   pharmacology   MeSH
• Hydroxybenzoates metabolism   MeSH
• Smoke analysis   MeSH
• Seaweed chemistry   MeSH
• Phaeophyceae chemistry   MeSH
• Pyrans isolation & purification   pharmacology   MeSH
• Plant Growth Regulators isolation & purification   pharmacology   MeSH
• Spinacia oleracea drug effects   growth & development   metabolism   MeSH
• Crops, Agricultural drug effects   growth & development   metabolism   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Cytokinins MeSH
• Dioxins MeSH
• eckol MeSH Browser
• Furans MeSH
• Hydroxybenzoates MeSH
• karrikinolide MeSH Browser
• Smoke MeSH
• phenolic acid MeSH Browser
• Pyrans MeSH
• Plant Growth Regulators MeSH