Ulva Fenestrata Research Articles

A new method for protein extraction from sea lettuce (Ulva fenestrata) via surfactants and alkaline aqueous solutions

Alternative protein sources such as seaweed can help relieve the pressure on land-based protein supply. This proof-of-concept study developed an extraction method to recover soluble and lipophilic proteins from the seaweed Ulva fenestrata. The method consisted of processing U. fenestrata with 0.1–0.5 % aqueous Triton X-114 solution and reprocessing the pellet with an alkaline aqueous solution. Then, the solubilized proteins were precipitated via acidification. The new method extracted 3.4-times more protein, measured as total amino acids, compared to the control with two alkaline aqueous extraction cycles. Triton disrupted the chloroplasts and likely solubilized lipophilic membrane proteins as supported by microstructure and polypeptide pattern analysis. Triton-derived protein extracts contained lipids inside the precipitates/aggregates and were richer in fatty acids typical of photosynthetic membranes. The higher extraction yields are proposed to result from membrane charge neutralization upon acidification, triggering interactions between the membrane lipids and their subsequent precipitation with the lipophilic membrane protein.

Brining as an effective method to stabilise sea lettuce (Ulva fenestrata) -impact on colour, texture, chemical characteristics and microbial dynamics

Brining as a cost-effective stabilising method to preserve the quality of fresh Ulva fenestrata was studied. The brines contained from 0 to 25 % (w/w) of sodium chloride or from 0 to 50 % sucrose and were combined with seaweed at a ratio of 1: 10 (w/v) prior to storage at 4 °C for up to 3 months. During this storage, the water activity of U. fenestrata was reduced from 0.94 to ≤0.89 with ≥15 % salt brines, which kept the microbial load <7 log (CFU/g) for 78 days. Among the sucrose brines, 50 % provided microbial shelf life <7 log (CFU/g) for 48 days. Further, 25 % salt or 50 % sucrose brines effectively retained the greenness (a*) of the U. fenestrata blades (< −20 a*-value for 80 days), while the tensile strength was only retained with 25 % salt brine (>3 Newton for 80 days). There was a time-dependent loss of crude proteins and fatty acids during storage, especially for 50 % sugar brined seaweed, where 58 % and 28 %, respectively, were lost after 20 days. Nutrients were best preserved in the 5 % salt-brine. Overall, the results indicate that brining with 25 % salt or 50 % sugar yields microbial stability and maintained colour of U. fenestrata for at least 48 days, with the former even exceeding 78 days at 4 °C, however, at a cost of nutritional value.

Sensory and consumer aspects of sea lettuce (Ulva fenestrata) – impact of harvest time, cultivation conditions and protein level

The green seaweed Ulva fenestrata is a future food candidate, however, both compositional, e.g. protein content, and sensory qualities depend on cultivation and harvest conditions. The aim was to explore sensory qualities of, and consumer attitudes to, U. fenestrata derived from three different cultivation conditions and three harvest times. U. fenestrata was cultivated at sea and in two different land-based tank settings, one mimicking seawater and one with added process water from fishing industry to increase protein content. The seaweed was subjected to sensory analysis performed by an analytical sensory panel and a focus group consisting of consumers. The former assessed the seaweed as dried whole blades (9 samples) and as emulsions (9 samples). Consumers assessed whole blades and a vegan spread enriched with powdered U. fenstrata. All seaweed samples were intensely green; had tastes of umami, salt, bitter, and sour; odours and flavours of grass and fresh seaweed; and had a crispy texture. Cultivation in tanks resulted in a crispier texture than sea cultivation (p<0.001). Protein content increased from 14.4% to 21.6% in tank cultivation with process waters, which increased green colour intensity (p<0.007) and decreased intensity of bitterness (p<0.001). Overall, consumers were positive towards seaweeds as foods.

Seasonal Distribution of Fishes at Nearshore Meadows Predominated by Zostera marina and Ulva fenestrata in the Stark Strait (Peter the Great Gulf, Sea of Japan)

Seasonal Distribution of Fishes at Nearshore Meadows Predominated by Zostera marina and Ulva fenestrata in the Stark Strait (Peter the Great Gulf, Sea of Japan)

НАХОДКИ ЛАМИНАРИЕВЫХ И ДРУГИХ ВОДОРОСЛЕЙ В УЛОВАХ ДОННЫМ ТРАЛОМ И ЯРУСОМ У ЗАПАДНОГО ПОБЕРЕЖЬЯ КАМЧАТКИ В 2018–2023 гг.

Data are provided on findings of marine macroalgae during bottom trawls and longline fishing on the Western Kamchatka shelf in 2018-2023. During the study period, algae were noted at 65 stations in the depth range from 20 to 350 m. Most of the algae findings were found in the Kamchatka-Kuril fishing subzone, within the South Kamchatka Nature Reserve. Among the macrophytes, representatives of the order Laminariales predominated: Agarum pertusum, A. clathratum, Alaria esculenta, Arthrothamnus bifidus, Eualaria fistulosa, Hedophyllum bongardianum, H. dentigerum, Laminaria yezoensis, Laminaria inclinatoriza and Thalassiophyllum clathrus. For southwestern Kamchatka, only 9 out of 13 species of kelp algae indicated in the literature were discovered. Brown algae Fucus distichus, Desmarestia intermedia, red algae – Ptilota asplenioides, Turnerella mertensiana and lamellar green algae – Ulva fenestrata were found sporadically. A comparative analysis of aerial photography data of coastal areas from Cape Sivuchy to Cape Lopatka in 2002 and modern satellite images did not reveal significant changes in the distribution of littoral and sublittoral algae beds. In the coastal line of capes Sivuchy, Kambalny and Maria that we studied, the kelp belt with an average width of 100-130 m reached in the summer of 2018–2023 the total coverage area is 1.92 km2. The use of accompanying data when conducting bottom surveys of commercial invertebrates and fish, longline cod fisheries, together with the analysis of satellite images, allows for an expert assessment of changes in the species composition and distribution of kelp algae, and is also a promising tool for monitoring the state of macrophyte communities in the Far Eastern seas of Russia.

The first record of a non-native seaweed from South Georgia and confirmation of its establishment in the Falkland Islands: Ulva fenestrata Postels & Ruprecht

Detecting non-native species can be challenging, particularly in the case of taxa such as seaweeds, which can be difficult to distinguish based on morphology and often require molecular-assisted taxonomy for reliable identification. The sub-Antarctic island of South Georgia supports unique and important marine biodiversity, including a rich seaweed flora, but despite its isolation, its inshore ecosystems are susceptible to the introduction of potentially invasive non-native species. Here, we provide the first report of a non-native seaweed in South Georgia, Ulva fenestrata Postels & Ruprecht (Ulvophyceae, Chlorophyta), and confirm its widespread presence in the Falkland Islands via molecular-assisted taxonomy. Phylogenetic analyses of tufA and rbcL-3P genetic markers enabled the identification of a specimen collected from Grytviken, South Georgia in November 2021 as U. fenestrata. In terms of tufA sequence, this sample was identical to specimens collected from four sites spanning West and East Falkland in 2013 and 2018. This study represents the second Southern Hemisphere record of U. fenestrata, which is generally regarded as a Northern Hemisphere species. Our findings provide a foundation for monitoring this potentially invasive species in South Georgia, and for determining its likely source and mode of arrival, while emphasising the importance of robust biosecurity measures.

Airborne dimethyl sulfide (DMS) cues dimethylsulfoniopropionate (DMSP) increases in the intertidal green alga Ulva fenestrata

Although the use of airborne molecules as infochemicals is common in terrestrial plants, it has not been shown to occur in an ecologically relevant context in marine seaweeds. Like terrestrial plants, intertidal plants spend part of their lives emersed at low tide and release volatile organic compounds (VOCs) into the air when they are grazed or physiologically stressed. We hypothesized seaweeds could use airborne VOCs as infochemicals and respond to them by upregulating a keystone defensive metabolite, dimethylsulfoniopropionate (DMSP). We conducted laboratory and field experiments in which Ulva fenestrata was exposed to airborne dimethyl sulfide (DMS), a volatile antiherbivore and antioxidant metabolite released when the seaweed is grazed or physiologically stressed. In the laboratory, U. fenestrata exposed to DMS had 43–48% higher DMSP concentrations, relative to controls, 6–9 days after exposure. In the field, U. fenestrata 1 m downwind of DMS emitters had 19% higher DMSP concentrations than upwind seaweeds after 11 days. To our knowledge, this is the first demonstration of a marine plant using an airborne molecule released when damaged to elicit defensive responses. Our study suggests that the ability to detect airborne compounds has evolved multiple times or before the divergence of terrestrial plants and green algae.

Determination of nitrogen content in Ulva fenestrata by color image analysis – a rapid and cost-efficient method to estimate nitrogen content in seaweeds

There is an increasing interest in the cultivation of seaweeds for food and feed, and the seaweed aquaculture industry is rapidly developing. The nutritional status of the seaweeds is important to ensure a good quality crop. Cost-efficient and straightforward methods for farmers to analyze their crop are essential for the successful development of the industry. In this study, we developed non-destructive, labor- and cost-efficient models to estimate the nitrogen content in the crop seaweed Ulva fenestrata by color image analysis. We quantified tissue nitrogen content and thallus color in sea-farmed seaweed every week throughout a whole cultivation season (15 consecutive weeks) and analyzed data with linear regression models. We showed that color image analysis accurately estimated the nitrogen content in the seaweed (R2 = 0.944 and 0.827 for fresh tissue and dried powder, respectively), and through tenfold cross validation we showed that the developed models were robust and precise. Based on these models, we developed a web-based application that automatically analyzes the nitrogen content of U. fenestrata. Furthermore, we produced a color guide that can easily be brought to the farm for onsite crude estimation of the nitrogen content of U. fenestrata. Our results demonstrate that color can be a powerful tool for seaweed farmers (and researchers) to estimate seaweeds’ nutritional status. We anticipate that similar models can be developed for other commercially interesting seaweed species.

Closed life-cycle aquaculture of sea lettuce (Ulva fenestrata): performance and biochemical profile differ in early developmental stages

Sea lettuce (Ulva) aquaculture has increased the last decade due to high productivity, wide environmental tolerance, and interesting functional and nutritional properties of the crop. Research focus has mainly been on adult biomass production, but knowledge of performance and biochemical content of early developmental stages – which are the basis to any large-scale production - is still limited. The life-history ofUlvaalternates between a diploid sporophytic life-stage and a haplontic gametophytic life-stage. Whereas the sporophyte give raise to recombinant gametophytes through zoids, gametophytes can give raise to parthenogenetically developing, clonal gametes in absence of a mating partner. This study shows that recombinant gametophytes have a faster ontogenetic development, higher growth rate, as well as higher protein, fatty acid, and pigment contents compared to clonal gametophytes of the cropUlva fenestrata. Nutrient addition is required for a normal development, but temperature and swarmer density have relatively small effects on the hatchery success, relative growth rate and biochemical profile of the juvenile biomass. Our study reveals that the selection of the life-history-phase in novel sea lettuce crop strains could largely contribute to the emerging seaweed aquaculture sector.

Combining pressing and alkaline extraction to increase protein yield from Ulva fenestrata biomass

Many seaweed species have a high production potential and attract interest as future protein sources. A high fiber and ash content, however, demand extraction of the protein to improve its digestibility and protein utilization in food or feed. This study explores three different approaches for protein extraction from Ulva fenestrata in order to maximize the protein extraction yield. Soluble protein was recovered either by mechanical pressing or by homogenization and osmotic shock of the biomass followed by alkaline extraction. The soluble protein was then concentrated by isoelectric precipitation. A combined procedure was carried out by pressing the biomass and following subjecting the residual pulp fraction to homogenization, osmotic shock and alkaline extraction. The three methods were ranked as follows with respect to protein extraction yield (as % of biomass protein); the combined method (23.9 ± 0.3%)> the alkaline extraction (6.8 ± 0.2%)> mechanical pressing (5.0 ± 0.2%). The significant increase when combining the methods was ascribed to a high precipitation yield after alkaline extraction of the pulp, hypothesized to be due to a reduced conductivity of the alkali-soluble protein fraction when derived from pulp rather than whole biomass.

Harvest Time Can Affect the Optimal Yield and Quality of Sea Lettuce (Ulva fenestrata) in a Sustainable Sea-Based Cultivation

Seaweed biomass is a renewable resource with multiple applications. Sea-based cultivation of seaweeds can provide high biomass yields, low construction, operation, and maintenance costs and could offer an environmentally and economically sustainable alternative to land-based cultivations. The biochemical profile of sea-grown biomass depends on seasonal variation in environmental factors, and the optimization of harvest time is important for the quality of the produced biomass. To identify optimal harvest times of Swedish sea-based cultivated sea lettuce (Ulva fenestrata), this study monitored biomass yield, morphology, chemical composition, fertility, and biofouling at five different harvesting times in April – June 2020. The highest biomass yields (approximately 1.2 kg fw [m rope]–1) were observed in late spring (May). The number and size of holes in the thalli and the amount of fertile and fouled tissue increased with prolonged growth season, which together led to a significant decline in both biomass yield and quality during summer (June). Early spring (April) conditions were optimal for obtaining high fatty acid, protein, biochar, phenolic, and pigment contents in the biomass, whereas carbohydrate and ash content, as well as essential and non-essential elements, increased later in the growth season. Our study results show that the optimal harvest time of sea-based cultivatedU. fenestratadepends on the downstream application of the biomass and must be carefully selected to balance yield, quality, and desired biochemical contents to maximize the output of future sea-based algal cultivations in the European Northern Hemisphere.

Cross-processing herring and salmon co-products with agricultural and marine side-streams or seaweeds produces protein isolates more stable towards lipid oxidation

Herring and salmon filleting co-products were pH-shift processed together with seven antioxidant-containing raw materials (“helpers”) including lingonberry-, apple-, oat-, barley- and shrimp-co-products, and two seaweeds (Saccharina latissima, Ulva fenestrata) to produce protein isolates stable towards lipid oxidation. Malondialdehyde (MDA) and 4-hydroxy-(E)-2-hexenal (HHE) levels revealed that all helpers, except shrimp shells, to different extents retarded lipid oxidation both during pH-shift-processing and ice storage. The three helpers performing best were: lingonberry press-cake > apple pomace ∼ Ulva. Color of protein isolates was affected by helper-derived pigments (e.g., anthocyanins, carotenoids, chlorophyll) and lipid oxidation-induced changes (e.g., metHb-formation, pigment-bleaching). In conclusion, combining fish co-products with other food side-streams or seaweeds during pH-shift processing appears a promising new tool to minimize lipid oxidation of protein isolates, both during their production and subsequent storage. Lingonberry press-cake was the most efficient helper but provided dark color which may narrow product development possibilities, something which requires further attention.

Molecular genetic diversity of seaweeds morphologically related to Ulva rigida at three sites along the French Atlantic coast.

Foliose species of the genus Ulva are notoriously difficult to identify due to their variable morphological characteristics and high phenotypic plasticity. We reassessed the taxonomic status of several distromatic foliose Ulva spp., morphologically related to Ulva rigida, using DNA barcoding with the chloroplastic tufA and rbcL (for a subset of taxa) genes for 339 selected attached Ulva specimens collected from three intertidal rocky sites. Two of the collection sites were in Brittany and one site was in Vendée, along the Atlantic coast of France. Molecular analyses included several museum specimens and the holotype of Ulva armoricana Dion, Reviers & Coat. We identified five different tufA haplotypes using a combination of phylogenetic analysis, with the support of several recently sequenced holotypes and lectotypes, and a species delimitation method based on hierarchical clustering. Four haplotypes were supported by validly named species: Ulva australis Areschoug, Ulva fenestrata Postels & Ruprecht, Ulva lacinulata (Kützing) Wittrock and U. rigida C. Agardh. The later was additionally investigated using rbcL. The fifth haplotype represented exact sequence matches to an unnamed species from European Atlantic coasts. Our results support: (1) the synonymy of both U. rigida sensu Bliding non C. Agardh and U. armoricana with U. lacinulata. This finding is based on current genetic analysis of tufA from the U. armoricana holotype and recent molecular characterization of the lectotype of U. laetevirens, which is synonymous to U. australis, (2) the presence of U. australis as a misidentified introduced species in Brittany, and (3) the presence of U. fenestrata and U. rigida in southern Brittany. The taxonomic history of each species is discussed, highlighting issues within distromatic foliose taxa of the genus Ulva and the need to genetically characterize all its available type specimens.

Ulva fenestrata protein – Comparison of three extraction methods with respect to protein yield and protein quality

Seaweed is gaining attention as a possible alternative and sustainable source of proteins. This study investigates three protein extraction methods and their effect on protein yield and quality when applied to Ulva fenestrata. Two of the methods included alkaline extractions (pH-shifts); one version solubilizing the proteins at pH 8.5 and one solubilizing them at pH 8.5 followed by pH 12 (pH 8.5 + 12). The third method was a mechanical pressing, using a double screw press. All extraction methods were followed by isoelectric precipitation to concentrate the proteins. Extraction at pH 8.5 gave the significantly highest total protein yield after the isoelectric precipitation, followed by extraction at pH 8.5 + 12 and lastly mechanical extraction gave the lowest yield. Proteins extracted with both alkaline methods had a significantly higher solubility at pH 7 and pH 9, compared to proteins from the mechanical pressing. There were no significant differences between the three methods in total D/L-amino acid ratio. Amino acid cross-links measured as lysinoalanine (LAL) and lanthionine (LAN) where found in significantly higher amounts in alkali-extracted proteins compared to mechanically extracted, however not to a degree that expect to compromise functional or nutritional quality. Further, no significant difference in protein in vitro digestibility was found between extraction methods. In conclusion, results indicated that protein extraction at pH 8.5 can be recommended, especially regarding total protein yield and solubility of the final protein extract.

Phylogenomic analysis of the chloroplast genome of the green-tide forming macroalga Ulva intestinalis Linnaeus (Ulvophyceae, Chlorophyta)

Ulva intestinalis Linnaeus 1753 (Ulvophyceae, Chlorophyta) is a marine green macroalga that is distributed on coasts of the Yellow Sea and the Bohai Sea in China. Here, the complete chloroplast genome of U. intestinalis was constructed and analyzed comparatively. The chloroplast genome of U. intestinalis is a 99,041-bp circular molecule that harbors a total of 112 genes including 71 protein-coding genes (PCGs), 26 transfer RNA genes (tRNAs), three ribosomal RNA genes (rRNAs), three free-standing open reading frames (orfs) and nine intronic orfs, and ten introns in seven genes (atpA, infA, psbB, psbC, petB, rrnL, and rrnS). The maximum likelihood (ML) phylogenomic analysis shows that U. intestinalis firstly groups with Ulva compressa, and then these two species together with the Ulva australis–Ulva fenestrata–Ulva rotundata subclade form a monophyletic clade, Ulva lineage II. U. intestinalis chloroplast genome is the only one in Ulva lineage II where the reversal of a collinear block of two genes (psbD–psbC) did not occur, and its genome structure is consistent with that of most chloroplast genomes in Ulva lineage I, indicating that the similarity of genome structure is not completely related to the genetic relationship of Ulva species. Our genomic data will facilitate the development of specific high-resolution chloroplast molecular markers for rapid identification of U. intestinalis, and help us understand its population diversity and genetic characteristics on a global scale.

Sustainable Large-Scale Aquaculture of the Northern Hemisphere Sea Lettuce, Ulva fenestrata, in an Off-Shore Seafarm

The growing world population demands an increase in sustainable resources for biorefining. The opening of new farm grounds and the cultivation of extractive species, such as marine seaweeds, increases worldwide, aiming to provide renewable biomass for food and non-food applications. The potential for European large-scale open ocean farming of the commercial green seaweed crop Ulva is not yet fully realized. Here we conducted manipulative cultivation experiments in order to investigate the effects of hatchery temperature (10 and 15 °C), nutrient addition (PES and 3xPES) and swarmer density (500 and 10,000 swarmers ml−1) on the biomass yield and biochemical composition (fatty acid, protein, carbohydrate, pigment and phenolic content) of off-shore cultivated Ulva fenestrata in a Swedish seafarm. High seedling densities were optimal for the growth of this northern hemisphere crop strain and significantly increased the mean biomass yield by ~84% compared to low seedling densities. Variations of nutrients or changes in temperature levels during the hatchery phase were not necessary to increase the subsequent growth in an open-water seafarm, however effects of the factors on the thallus habitus (thallus length/width) were observed. We found no significant effect of the environmental factors applied in the hatchery on the total fatty acid or crude protein content in the off-shore cultivated Ulva. However, low seedling density and low temperature increased the total carbohydrate content and furthermore, high temperature in combination with high nutrient levels decreased the pigment content (chlorophyll a, b, carotenoids). Low temperature in combination with high nutrient levels increased the phenolic content. Our study confirms the successful and sustainable potential for large-scale off-shore cultivation of the Scandinavian crop U. fenestrata. We conclude that high seedling density in the hatchery is most important for increasing the total biomass yield of sea-farmed U. fenestrata, and that changing temperature or addition of nutrients overall does not have a large effect on the biochemical composition. To summarize, our study contributes novel insights into the large-scale off-shore cultivation potential of northern hemisphere U. fenestrata and underpins suitable pre-treatments during the hatchery phase of seedlings to facilitate a successful and cost-efficient large-scale rope cultivation.

Effect of storage conditions on lipid oxidation, nutrient loss and colour of dried seaweeds, Porphyra umbilicalis and Ulva fenestrata, subjected to different pretreatments

Here we evaluated the levels of lipid oxidation products, fatty acids, ascorbic acid and colour of Porphyra and Ulva after oven-drying at 40 °C, and during subsequent storage for ≥370 days under light, semi-light and dark conditions. Part of the seaweed was pre-soaked in freshwater or pre-coated with a whey protein mixture. Controls consisted of freeze-dried seaweeds. Throughout storage there was a moderate development of the lipid oxidation-derived aldehydes, malondialdehyde, 4-hydroxy-trans-2-hexenal and 4-hydroxy-trans-2-nonenal, while there was a great loss of unsaturated fatty acids and ascorbic acid. Light storage and freeze-drying stimulated the fatty acid loss as well as pigment bleaching, seen as increased a*-values. For Ulva, the coating reduced malondialdehyde, 4-hydroxy-trans-2-hexenal and 4-hydroxy-trans-2-nonenal formation during drying and slightly prevented loss of polyunsaturated fatty acids during light storage. Pre-soaking in freshwater had no effect on the seaweed stability, although it reduced the ash content and thereby increased the relative content of ascorbic acid and fatty acids of the biomasses.

In vitro digestibility and Caco-2 cell bioavailability of sea lettuce (Ulva fenestrata) proteins extracted using pH-shift processing

Seaweed is a promising sustainable source of vegan protein as its farming does not require arable land, pesticides/insecticides, nor freshwater supply. However, to be explored as a novel protein source the content and nutritional quality of protein in seaweed need to be improved. We assessed the influence of pH-shift processing on protein degree of hydrolysis (%DH), protein/peptide size distribution, accessibility, and cell bioavailability of Ulva fenestrata proteins after in vitro gastrointestinal digestion. pH-shift processing of Ulva, which concentrated its proteins 3.5-times, significantly improved the %DH from 27.7±2.6% to 35.7±2.1% and the amino acid accessibility from 56.9±4.1% to 72.7±0.6%. Due to the higher amino acid accessibility, the amount of most amino acids transported across the cell monolayers was higher in the protein extracts. Regarding bioavailability, both Ulva and protein extracts were as bioavailable as casein. The protein/peptide molecular size distribution after digestion did not disclose a clear association with bioavailability.

Cellulose from the green macroalgae Ulva lactuca: isolation, characterization, optotracing, and production of cellulose nanofibrils

We report (1) successful extraction and characterization of cellulose from northern hemisphere green macroalgae Ulva lactuca (Ulva fenestrata) collected along the Swedish west coast and cultivated indoors under controlled conditions, followed by (2) its utilization in the production of lignin-free cellulose nanofibrils (CNF). Cellulose was extracted by sequential treatment with ethanol, hydrogen peroxide, sodium hydroxide, and hydrochloric acid, yielding a cellulose-rich insoluble fraction. The extracted cellulose was disintegrated into CNF using a mechanical homogenization process without any further enzymatic pre-treatments. In addition, regenerated cellulose was prepared. XRD characterization of the CNF showed characteristic peaks for the cellulose I allomorph and confirmed that the nanofibrils were semicrystalline with a crystallinity index of 48%. Regenerated cellulose was mostly amorphous with an XRD pattern indicating the presence of the cellulose II allomorph. The cellulose fractions were essentially free from inorganic substances and thermally stable up to around 260 °C. Structural mapping with CP-MAS 13C-NMR sustains the cellulose content of CNF and regenerated cellulose, respectively, yet ion chromatography identified the presence of 10–15% xylose in the fractions. Optotracing was used as a novel and non-disruptive tool to selectively assess the polysaccharide composition of the cellulose fractions and produced CNF aiming to shed light on this hitherto non-resolved origin of xylose in Ulva cell wall matter. Fluorescence excitation and emission spectra of a panel of 4 oligothiophenes identified and verified the presence of cellulose and sustain the conclusion that the isolated fractions consist of cellulose intertwined with a small amount of a xylose-containing glucan copolymer.Graphic abstract

Effects of water soluble extracts from marine algae on root growth in soybean seedlings

Data on the effects of water soluble extracts of red marine algae—such as Grateloupia divaricate, Chondrus pinnulatus, Neorhodomela larix, and Tichocarpus crinitus—brown marine algae—such as Stephanocystis crassipes, Coccophora langsdorfii, Sphaerotrichia divaricata, Saccharina japonica, Sargassum pallidum, and Chorda filum—and green marine algae—such as Ulva fenestrata and Codium fragile—on root growth in soybean seedlings (Glycine max (L.) Merr.) have been presented. The stimulatory effects of extracts containing T. crinitus, N. Larix, C. pinnulatus, and S. crassipes algae at low (10−4 g/mL) and ultralow (10−10–10−12 g/mL) concentrations are defined.