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DNA barcoding analysis, using tufA, revealed considerable differences between the expected and observed species inventory of Ulva sensu lato in the Baltic and North Sea areas of the German state of Schleswig-Holstein. Of 20 observed genetic entities, at least four (U. australis, U. californica, U. gigantea and Umbraulva dangeardii) had been introduced recently, whereas three others (one Ulva sp. and two Blidingia spp.) could not be identified at the species level and could also represent recently introduced species. In addition, the observed distributions of Kornmannia leptoderma and U. rigida were much more extensive than indicated by historical records, whereas Blidingia minima and Gayralia oxysperma were absent or much less common than expected. Barcoding analysis also revealed that both U. tenera (type material) and U. pseudocurvata (historical vouchers) from Helgoland, an off-shore island in the North Sea, actually belong to U. lactuca, a species that appears to be restricted to this island. Furthermore, past morphological descriptions of U. intestinalis and U. compressa have apparently been too restrictive and have been responsible for numerous misidentifications. The same is true for U. linza, which, in northern Germany, clusters into two genetically closely related but morphologically indistinguishable entities. One of these entities is present on Helgoland, while the second is present on North Sea and Baltic Sea mainland coasts. [ABSTRACT FROM AUTHOR]

To resolve historical misinterpretations of species descriptions and to comprehend the morphological diversity together with the distribution of Ulva compressa Linnaeus in northern Germany, a morphological and molecular study was undertaken of recently collected specimens and herbarium vouchers. Phylogenetic analyses from sequences of the plastid encoded tufA gene confirmed that U. compressa is abundant along the German Baltic Sea and North Sea coasts. We were able to genetically confirm the presence of U. compressa in the Baltic Sea below salinities of 15 PSU. However, we detected morphologies agreeing with the attached and branched tubular type material only in the North Sea, while U. compressa on Baltic Sea coasts indiscriminately exhibited a very distinct morphology of sheet-like thalli that were always unattached, with the exception of one collection site. Drifting forms were also frequently detected in the Wadden Sea, but not on the island of Helgoland. The tufA sequences of attached and tubular forms of U. compressa from the German Wadden Sea were identical to the drifting sheets found in the Wadden and Baltic Seas and the sequence divergence was extremely small at ≤0.9%. The proliferating, blade-like thalli of U. compressa appear as a nuisance ecotype that is able to form massive accumulations associated with oxygen depletion. Mass accumulations were observed to cause severe damage and increased mortality of habitat forming Zostera and Ruppia populations. [ABSTRACT FROM AUTHOR]

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., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: João P. Trigo, Ingrid Undeland, and Mehdi Abdollahi have a patent pending to Chalmers Ventures AB as a result of the work described in this article. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The green seaweed Ulva relies on associated bacteria for morphogenesis and is an important model to study algal-bacterial interactions. Ulva -associated bacteria exhibit high turnover across environmental gradients, leading to the hypothesis that bacteria contribute to the acclimation potential of the host. However, the functional variation of these bacteria in relation to environmental changes remains unclear. We analyzed 91 Ulva samples across a 2000-kilometer Atlantic-Baltic Sea salinity gradient using metagenomic sequencing. Metabolic reconstruction of 639 metagenome-assembled genomes revealed widespread potential for carbon, nitrogen, sulfur, and vitamin metabolism. Although the R 2 value for salinity explained 70% of taxonomic variation, it accounted only for 17% of functional variation. The limited variation was attributed to typical high-salinity bacteria exhibiting enrichment in genes for thiamine, pyridoxal, and betaine biosynthesis, which likely contribute to stress mitigation and osmotic homeostasis in response to salinity variations. Our results emphasize the importance of functional profiling to understand the seaweed holobiont and its collective response to environmental change.

Ulva , a genus of green macroalgae commonly known as sea lettuce, has long been recognized for its nutritional benefits for food and feed. As the demand for sustainable food and feed sources continues to grow, so does the interest in alternative, plant-based protein sources. With its abundance along coastal waters and high protein content, Ulva spp. have emerged as promising candidates. While the use of Ulva in food and feed has its challenges, the utilization of Ulva in other industries, including in biomaterials, biostimulants, and biorefineries, has been growing. This review aims to provide a comprehensive overview of the current status, challenges and opportunities associated with using Ulva in food, feed, and beyond. Drawing on the expertise of leading researchers and industry professionals, it explores the latest knowledge on Ulva' s nutritional value, processing methods, and potential benefits for human nutrition, aquaculture feeds, terrestrial feeds, biomaterials, biostimulants and biorefineries. In addition, it examines the economic feasibility of incorporating Ulva into aquafeed. Through its comprehensive and insightful analysis, including a critical review of the challenges and future research needs, this review will be a valuable resource for anyone interested in sustainable aquaculture and Ulva' s role in food, feed, biomaterials, biostimulants and beyond.

The green seaweed Ulva is a model system to study seaweed-bacteria interactions, but the impact of environmental drivers on the dynamics of these interactions is little understood. In this study, we investigated the stability and variability of the seaweed-associated bacteria across the Atlantic-Baltic Sea salinity gradient. We characterized the bacterial communities of 15 Ulva sensu lato species along 2,000 km of coastline in a total of 481 samples. Our results demonstrate that the Ulva-associated bacterial composition was strongly structured by both salinity and host species (together explaining between 34% and 91% of the variation in the abundance of the different bacterial genera). The largest shift in the bacterial consortia coincided with the horohalinicum (5-8 PSU, known as the transition zone from freshwater to marine conditions). Low-salinity communities especially contained high relative abundances of Luteolibacter, Cyanobium, Pirellula, Lacihabitans and an uncultured Spirosomaceae, whereas high-salinity communities were predominantly enriched in Litorimonas, Leucothrix, Sulfurovum, Algibacter and Dokdonia. We identified a small taxonomic core community (consisting of Paracoccus, Sulfitobacter and an uncultured Rhodobacteraceae), which together contributed to 14% of the reads per sample, on average. Additional core taxa followed a gradient model, as more core taxa were shared between neighbouring salinity ranges than between ranges at opposite ends of the Atlantic-Baltic Sea gradient. Our results contradict earlier statements that Ulva-associated bacterial communities are taxonomically highly variable across individuals and largely stochastically defined. Characteristic bacterial communities associated with distinct salinity regions may therefore facilitate the host's adaptation across the environmental gradient., (© 2022 The Authors. Molecular Ecology published by John Wiley & Sons Ltd.)

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., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Over the past decade, Ulva compressa, a cosmopolitan green algal species, has been identified as a component of green tides in the Yellow Sea, China. In the present study, we sequenced and annotated the complete chloroplast genome of U. compressa (alpha-numeric code: RD9023) and focused on the assessment of genome length, homology, gene order and direction, intron size, selection strength, and substitution rate. We compared the chloroplast genome with the mitogenome. The generated phylogenetic tree was analyzed based on single and aligned genes in the chloroplast genome of Ulva compared to mitogenome genes to detect evolutionary trends. U. compressa and U. mutabilis chloroplast genomes had similar gene queues, with individual genes exhibiting high homology levels. Chloroplast genomes were clustered together in the entire phylogenetic tree and shared several forward/palindromic/tandem repetitions, similar to those in U. prolifera and U. linza. However, U. fasciata and U. ohnoi were more divergent, especially in sharing complementary/palindromic repetitions. In addition, phylogenetic analyses of the aligned genes from their chloroplast genomes and mitogenomes confirmed the evolutionary trends of the extranuclear genomes. From phylogenetic analysis, we identified the petA chloroplast genes as potential genetic markers that are similar to the tufA marker. Complementary/forward/palindromic interval repetitions were more abundant in chloroplast genomes than in mitogenomes. Interestingly, a few tandem repetitions were significant for some Ulva subspecies and relatively more evident in mitochondria than in chloroplasts. Finally, the tandem repetition [GAAATATATAATAATA × 3, abbreviated as TRg)] was identified in the mitogenome of U. compressa and the conspecific strain U. mutabilis but not in other algal species of the Yellow Sea. Owing to the high morphological plasticity of U. compressa, the findings of this study have implications for the rapid non-sequencing detection of this species during the occurrence of green tides in the region., Competing Interests: The authors have declared that no competing interests exist.

Background: In the United States, people over the age of 65 years will account for 20% of the population by 2030, and these elders are more likely to have chronic comorbid complex health problems. Sixty-three percent use complementary health approaches (CHAs) but less than half disclose their use to their health care providers. Nurse practitioners (NPs) are the fastest growing population of primary care health providers., Purpose: This study identifies to what degree NPs with specialized training in geriatrics understand CHAs, use them themselves, encourage their patients to access them, and engage in CHA clinical dialogue., Methods: Cross-sectional online survey collecting quantitative and narrative data; US NPs with specialized training in geriatrics (n = 170, mean age 52 years, SD: 9.0, range: 29-73)., Results: Although NPs are knowledgeable about some CHA and believe they are beneficial for older adults to use, they want more education to help understand the effects of a variety of CHA, be more aware of possible treatment interactions, and to integrate CHA into the current health care system. Patient factors (impaired cognitive function, acute health problems, and not open to CHA), provider factors (inadequate CHA knowledge, limited referral paths and resources), and system factors (limited accessibility and availability of CHA in in-patient setting, CHA not covered by insurance, and limited clinical time) disrupt NPs from assessing and discussing CHA with their patients., Implications for Practice: There is a need to develop and implement NP practice guidelines for CHA clinical management for older adults and provide educational opportunities to incorporate CHA into clinical practice., Competing Interests: Competing interests: The authors report no conflicts of interest., (Copyright © 2021 American Association of Nurse Practitioners.)

Hydrogels based on the polysaccharide ulvan from the green macroalgae Ulva fenestrata were synthesized and evaluated as an adsorbent for heavy metals ions and methylene blue. Ulvan was extracted from Ulva fenestrata using diluted hydrochloric acid and recovered by precipitation with EtOH. The extracted ulvan was converted into ulvan dialdehyde via periodate-oxidation and subsequently combined with gelatin yielding hydrogels. The hydrogels showed good water-uptake capacity with a maximum swelling degree of 2400 % in water and 900 % in PBS buffer. Adsorption tests of methylene blue showed a maximum adsorption capacity of 465 mg/g. The adsorption data of methylene blue followed the pseudo-second order kinetics and agreed with the Langmuir adsorption isotherm. The maximum adsorption capacity of heavy metal ions was 14 mg/g for Cu 2+ , 7 mg/g for Co 2+ and 6 mg/g for Ni 2+ and Zn 2+ indicating that the hydrogels have a stronger affinity for Cu 2+ than for Co 2+ , Ni 2+ , and Zn 2+ ., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

As one of the most abundant and ubiquitous representatives of marine and brackish coastal macrophytobenthos communities, the genus Ulva is not only an important primary producer but also of ecological and morphogenetic interest to many scientists. Ulva mutabilis became an important model organism to study morphogenesis and mutualistic interactions of macroalgae and microorganisms. Here, we report that our collections of Ulva compressa Linnaeus (1753) from Germany are conspecific with the type strains of the model organism U. mutabilis Føyn (1958), which were originally collected at Olhão on the south coast of Portugal and have from that time on been maintained in culture as gametophytic and parthenogenetic lab strains. Different approaches were used to test conspecificity: (i) comparisons of vegetative and reproductive features of cultured material of U. mutabilis and German U. compressa demonstrated a shared morphological pattern; (ii) gametes of U. compressa and U. mutabilis successfully mated and developed into fertile sporophytic first-generation offspring; (iii) molecular phylogenetics and species delimitation analyses based on the Generalized Mixed Yule-Coalescent method showed that U. mutabilis isolates (sl-G[mt+]) and (wt-G[mt-]) and U. compressa belong to a unique Molecular Operational Taxonomic Unit. According to these findings, there is sufficient evidence that U. mutabilis and U. compressa should be regarded as conspecific., (© 2018 Phycological Society of America.)

Purpose: The study aims are to (a) describe nurse practitioners' (NPs') belief in effectiveness, knowledge, referral, and use of complementary/alternative therapies (C/ATs), (b) explore the initiation of C/AT dialogue between NPs and their patients, and (c) examine the relationships between demographic variables and NP C/AT knowledge, beliefs, use, referrals., Data Sources: A mixed-method cross-sectional online survey of licensed NPs (N = 2874) from a Midwestern state was analyzed using descriptive statistics, thematic analysis, and content analysis., Conclusions: NPs (n = 410) report the most knowledge about prayer (40%) and mind-body practices (32%). Many NPs (84%) report using vitamins for personal use and 85% refer their patients for massage/bodywork. Most (95%) believe NPs should have knowledge of the most common C/AT and 81% believe C/AT have a legitimate use in allopathic medicine. NPs' knowledge, belief, use, and referral of C/AT are significantly correlated. NPs initiate C/AT dialogue with their patients 54% of the time. Factors that impact the NP and patient C/AT dialogue include patient/family openness, nature of the health problem, NP C/AT knowledge, time, and accessibility., Implications for Practice: Centralized C/AT sources could help expedite C/AT referrals. Implementing workplace C/AT clinics could help build knowledge, referral, personal use, and acceptance of C/AT., (©2014 American Association of Nurse Practitioners.)

Background: This study describes a modified catheterization technique with subcutaneously implanted port catheters to be inserted in a retrograde manner across the aortic valve into the left heart ventricle through the right carotid artery to measure organ perfusion., Materials and Methods: The specially designed arterial port catheters were implanted in New Zealand rabbits (n = 11, 3.7 +/- 0.1 kg [mean +/- SEM]) under iv anesthesia (medetomidine/ketamine) and single-shot perioperative antibiotic therapy. Hemodynamics were registered continuously during the operation via an ear artery catheter., Results: Implantation of ports was performed in all animals (11/11) without major complications (mean operation time: 70 +/- 3 min). We did not observe catheter-associated arrhythmia, fall in mean arterial pressure (MAP before and post OP: 70 +/- 2 and 68 +/- 2 Torr, respectively), or change in arterial oxygen saturation (SaO2 before and post OP: 89 +/- 3 and 95 +/- 2%, respectively). With a specifically modified microsurgical insertion technique, cerebral blood supply was effectively preserved as evidenced from postmortem histological examinations, cerebral blood flow determination with fluorescent microspheres, and measurement of S-100b protein serum concentrations, a specific marker of neuronal damage. The positioning of the catheter tip in the left ventricle was found to be correct in 10/11 animals., Conclusions: Repeated and atraumatic microsphere injections into the left ventricle have become feasible by transcutaneous puncture of subcutaneous port systems over several weeks under light sedation. Hence, this new approach (i) avoids the necessity of repeated intracardiac injections and port insertions via thoracotomy, thus reducing the perioperative stress for the animals, and (ii) allows for the first time minimally invasive repetitive and chronic measurements of regional organ blood flow under various experimental settings., ((c)2001 Elsevier Science.)