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.

• Klíčová slova
• Antioxidant defense, Bioactive compounds, Gene expression, Immunity, Seaweeds, Tight junction proteins,
• MeSH
• antioxidancia metabolismus   MeSH
• Cyprinidae * růst a vývoj   metabolismus   imunologie   MeSH
• dieta veterinární   MeSH
• krmivo pro zvířata * analýza   MeSH
• mořské řasy * chemie   MeSH
• oxidační stres MeSH
• potravní doplňky MeSH
• Rhodophyta * chemie   MeSH
• střeva růst a vývoj   účinky léků   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antioxidancia MeSH

Seaweed-derived bioproducts are increasingly being deployed as an environmentally friendly and sustainable approach to crop management under stressful growth conditions including salinity. The bioactivities of seaweed-derived extracts are linked to the presence of diverse groups of bioactive compounds. In the present study, the phlorotannins present in the seaweed Ecklonia maxima and Kelpak®, an E. maxima-derived bioproduct, were quantified and identified. Three phlorotannins were identified in E. maxima, namely eckol, 2-phloroeckol, and dibenzodioxin-fucodiphloroethol. Eckol (589.11 - 822.54 μg l-1) and dibenzodioxin-fucodiphloroethol (85 - 895 μg l-1) were present in Kelpak®. Phlorotannin bioactivity was investigated in tomato seedlings grown under NaCl-induced salinity stress. The seedlings treated with either individual phlorotannins (i.e., eckol or a fraction containing 2-phloroeckol and dibenzodioxin-fucodiphloroethol) or Kelpak® resulted in a reprogramming of biomass allocation as indicated by an increased root-to-shoot ratio. Phlorotannin and Kelpak® treatments induced the accumulation of antioxidants with an attendant augmentation of the antioxidant capacities and inhibition of membrane damage in the NaCl-stressed seedlings. Kelpak® treatment induced an increase in abscisic acid (ABA) accumulation and phlorotannin treatments lowered the ABA content of the stressed seedlings. These results demonstrated that phlorotannins contributed to the ameliorative actions of Kelpak®. The more potent effects of Kelpak®, in comparison to phlorotannins, in improving dry matter accumulation, ABA content, antioxidative properties, and inhibiting tissue injury of the salt-stressed tomato seedlings may be attributed to the presence of other bioactive components in the Kelpak® product.

• Klíčová slova
• 2-Phloroeckol, Dibenzodioxin-fucodiphloroethol, Eckol, Kelpak®, Salinity stress, Seaweed biostimulants,
• MeSH
• antioxidancia * metabolismus   MeSH
• dioxiny metabolismus   farmakologie   MeSH
• mořské řasy metabolismus   MeSH
• Phaeophyceae * fyziologie   MeSH
• semenáček účinky léků   růst a vývoj   fyziologie   MeSH
• Solanum lycopersicum účinky léků   metabolismus   růst a vývoj   fyziologie   MeSH
• solný stres * účinky léků   MeSH
• taniny * metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antioxidancia * MeSH
• dioxiny MeSH
• eckol MeSH Prohlížeč
• taniny * MeSH

Alginate lyases have countless potential for application in industries and medicine particularly as an appealing biocatalyst for the production of biofuels and bioactive oligosaccharides. Solid-state fermentation (SSF) allows improved production of enzymes and consumes less energy compared to submerged fermentation. Seaweeds can serve as the most promising biomass for the production of biochemicals. Alginate present in the seaweed can be used by alginate lyase-producing bacteria to support growth and can secrete alginate lyase. In this perspective, the current study was directed on the bioprocessing of brown seaweeds for the production of alginate lyase using marine bacterial isolate. A novel alginate-degrading marine bacterium Enterobacter tabaci RAU2C which was previously isolated in the laboratory was used for the production of alginate lyase using Sargassum swartzii as a low-cost solid substrate. Process parameters such as inoculum incubation period and moisture content were optimized for alginate lyase production. SSF resulted in 33.56 U/mL of alginate lyase under the static condition maintained with 75% moisture after 4 days. Further, the effect of different buffers, pH, and temperature on alginate lyase activity was also analyzed. An increase in alginate lyase activity was observed with an increase in moisture content from 60 to 75%. Maximum enzyme activity was perceived with phosphate buffer at pH 7 and 37 °C. Further, the residual biomass after SSF could be employed as biofertilizer for plant growth promotion based on the preliminary analysis. To our knowledge, this is the first report stating the usage of seaweed biomass as a substrate for the production of alginate lyase using solid-state fermentation.

• Klíčová slova
• Enterobacter tabaci RAU2C, Alginate lyase, Seaweeds, Solid-state fermentation,
• MeSH
• algináty * metabolismus   MeSH
• biomasa MeSH
• Enterobacter * metabolismus   enzymologie   izolace a purifikace   růst a vývoj   MeSH
• fermentace * MeSH
• koncentrace vodíkových iontů MeSH
• kyselina glukuronová metabolismus   MeSH
• mořské řasy * mikrobiologie   MeSH
• Phaeophyceae mikrobiologie   MeSH
• polysacharid-lyasy * metabolismus   MeSH
• Sargassum * mikrobiologie   metabolismus   MeSH
• teplota MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• algináty * MeSH
• kyselina glukuronová MeSH
• poly(beta-D-mannuronate) lyase MeSH Prohlížeč
• polysacharid-lyasy * MeSH

This study measured 22 metal and metalloid concentrations in Hypnea musciformis from the Bakkhali River estuary and Saint Martin's Island, Bangladesh and determined their potential impact on consumption. Student t-tests showed a significant variation in metal concentrations between the two sampling sites (p < 0.05). Mean concentrations of Co (2.49 ± 0.05 mg/kg), Fe (793.29 ± 11.76 mg/kg), Mn (368.72 ± 4.87 mg/kg), Pb (3.82 ± 0.02 mg/kg), V (11.23 ± 0.20 mg/kg) and Zn (16.60 ± 0.28 mg/kg) were higher in samples collected from the Bakkhali River estuary compared to Saint Martin's Island, while mean concentrations of Ca (484.18 ± 4.68 mg/kg), Cd (2.44 ± 0.03 mg/kg), Mg (2112.70 ± 17.80 mg/kg), Mo (1.57 ± 0.06 mg/kg), Sr (2377.57 ± 29.98 mg/kg), and Ti (258.27 ± 4.62 mg/kg) were higher in samples collected from Saint Martin's Island. Eight heavy metals (Pb, Cd, Zn, Cu, Ni, Mn, Cr, Fe) were used to assess potential health risks for adults, but no potential health risk was detected (HQ value>1). This study reveals positive Se-HBV for H. musciformis collected from both sampling sites, indicating no potential risks involved with Hg toxicity.

• Klíčová slova
• Hazard index, Hazard quotients, Red seaweed, Selenium-Mercury balance,
• MeSH
• bioakumulace MeSH
• dospělí MeSH
• hodnocení rizik MeSH
• kadmium MeSH
• lidé MeSH
• mořské řasy * MeSH
• olovo MeSH
• polokovy * MeSH
• Rhodophyta MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kadmium MeSH
• olovo MeSH
• polokovy * 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.

• Klíčová slova
• countercurrent chromatography, isolation, marine lichen, mycosporine-like amino acids, photoprotection, red macroalgae,
• MeSH
• aminokyseliny chemie   MeSH
• lišejníky * chemie   MeSH
• mořské řasy * chemie   MeSH
• protiproudá chromatografie MeSH
• Rhodophyta * chemie   MeSH
• rostlinné extrakty metabolismus   MeSH
• ultrafialové záření MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• aminokyseliny MeSH
• rostlinné extrakty MeSH

Halimeda tuna (J. Ellis & Solander) J.V. Lamouroux is the only Halimeda species found in the Mediterranean Sea, and it is an important habitat former. In the northern Adriatic, H. tuna is among the ten most abundant seaweeds in the upper-infralittoral belt in spring and autumn. The modular thalli consist of serially arranged calcified segments. Calcification is closely related to photosynthesis, which causes alkalinization of the inter-utricular space and triggers aragonite formation. Understanding of the complex patterns of segment shape plasticity in relation to CaCO3content at different depth levels is still incomplete. Geometric morphometrics was used to investigate H. tuna segment shape variation on the depth transect at Cape Madona Nature Monument in the northern Adriatic Sea. The position on the thallus and the CaCO3 content of each studied segment were recorded, allowing slight changes in mineral content to be detected at the microscale of the segments. Our results showed that shape, size, or asymmetry of H. tuna segments were not significantly affected by depth. On the other hand, plants that grew deeper were generally more calcified. The apical and subapical segments contributed to the increase in CaCO3 content at the deeper sites, whereas the basal segments did not. This indicates that reniform or oval segments positioned apically or subapically play a key role in calcification of H. tuna in Mediterranean ecosystems.

• Klíčová slova
• Calcification, Depth transect, Geometric morphometrics, Green algae, Halimeda tuna, Phenotypic plasticity, Ulvophyceae,
• MeSH
• Chlorophyta * MeSH
• ekosystém MeSH
• fyziologická kalcifikace MeSH
• mořské řasy * MeSH
• tuňák MeSH
• uhličitany MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• uhličitany 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.

• Klíčová slova
• Arsenic, Arsenic speciation, Edible seaweeds, Health risks, Macroalgae,
• MeSH
• arsen * analýza   MeSH
• arsenikové přípravky * analýza   MeSH
• kontaminace potravin analýza   MeSH
• Laminaria * MeSH
• látky znečišťující životní prostředí * MeSH
• lidé MeSH
• mořské řasy * MeSH
• otrava arsenem * MeSH
• Sargassum * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• arsen * MeSH
• arsenikové přípravky * MeSH
• látky znečišťující životní prostředí * MeSH

The present study aimed to assess the levels of heavy metals and metalloids present in six seaweeds and their potential impact on consumption. The highest concentration of 11 metals, i.e., Be (0.47 mg/kg), Co (4.34 mg/kg), Cr (23.46 mg/kg), Cu (11.96 mg/kg), Fe (2290.26 mg/kg), Li (11.55 mg/kg), Ni (13.75 mg/kg), Pb (6.67 mg/kg), Ti (736.62 mg/kg), Tl (0.14 mg/kg), and V (33.09 mg/kg) were observed in Enteromorpha intestinalis (green seaweeds). Besides, the highest concentration of Ca (1071.09 mg/kg), Cd (5.81 mg/kg), Mn (1003.41 mg/kg), Sr (2838.86 mg/kg), and Zn (41.95 mg/kg) were found in Padina tetrastromatica (brown seaweeds). Eight metals (Pb, Cd, Zn, Cu, Ni, Mn, Cr, Fe) have been used to assess the potential health risk for adults, but no potential health risk was detected (HQ value > 1). The HI value of E. intestinalis and P. tetrastromatica were >1, implying that these two seaweeds are not safe for human consumption as there is a carcinogenic health risk for adults.

• Klíčová slova
• Bangladesh, Health risk, Heavy metals, Seaweed consumption,
• MeSH
• chemické látky znečišťující vodu * analýza   MeSH
• dospělí MeSH
• hodnocení rizik MeSH
• kadmium MeSH
• lidé MeSH
• monitorování životního prostředí MeSH
• mořské řasy * MeSH
• olovo MeSH
• polokovy * analýza   MeSH
• těžké kovy * analýza   MeSH
• zátoky MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Západoindické souostroví MeSH
• Názvy látek
• chemické látky znečišťující vodu * MeSH
• kadmium MeSH
• olovo MeSH
• polokovy * MeSH
• těžké kovy * 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
• algináty MeSH
• mořské řasy * MeSH
• oligosacharidy * MeSH
• potravní doplňky MeSH
• prebiotika MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• algináty MeSH
• oligosacharidy * MeSH
• prebiotika MeSH

Detrimental effects caused by the overuse of synthetic agrochemicals have led to the development of natural biostimulants such as seaweed extracts and plant growth-promoting rhizobacteria (PGPR) being used as an alternative, environmentally-friendly technology to improve crop growth and increase agricultural yields. The present study aimed to investigate the interactions between PGPR and a commercial seaweed extract on the growth and biochemical composition of onion (Allium cepa). A pot trial was conducted under greenhouse conditions where onion plants were treated individually with the two PGPR, namely Bacillus licheniformis (BL) and Pseudomonas fluorescens (PF) and a seaweed extract Kelpak® (KEL) and combinations of KEL + BL and KEL + PF. Growth and yield parameters were measured after 12 weeks. KEL-treated plants showed the best growth response and overcame the inhibitory effects of BL treatment. KEL-treated plants also had the highest chlorophyll content. PGPR application improved the mineral nutrition of onion with these plants having the highest mineral content in the leaves and bulb. All biostimulant treatments increased the endogenous cytokinin and auxin content with the highest concentrations generally detected in the PF-treated plants. These results suggest that co-application of different biostimulant classes with different modes of action could further increase crop productivity with an improvement in both growth and nutrition content being achieved in onion with the co-application of a seaweed extract and PGPR.

• Klíčová slova
• Biostimulants, Microbes, Minerals, Onion, Phytohormones, Seaweed,
• MeSH
• Bacillus licheniformis * metabolismus   MeSH
• česneky účinky léků   růst a vývoj   mikrobiologie   fyziologie   MeSH
• chlorofyl metabolismus   MeSH
• karotenoidy metabolismus   MeSH
• mořské řasy chemie   MeSH
• pěstování plodin metody   MeSH
• Pseudomonas fluorescens * metabolismus   MeSH
• regulátory růstu rostlin metabolismus   MeSH
• rostlinné extrakty farmakologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chlorofyl MeSH
• karotenoidy MeSH
• regulátory růstu rostlin MeSH
• rostlinné extrakty MeSH