Brown Seaweed Ascophyllum Nodosum Research Articles

Effects of Brown Seaweed (Ascophyllum nodosum) Supplementation on Enteric Methane Emissions, Metabolic Status and Milk Composition in Peak-Lactating Holstein Cows.

The dairy industry contributes significantly to anthropogenic methane emissions, which have an impact on global warming. This study aimed to investigate the effects of a dietary inclusion of brown seaweed Ascophyllum nodosum on enteric methane emissions (EMEs), hematological and blood biochemical profiles, and milk composition in dairy cows. Eighteen Holstein cows were divided into three groups: CON (non-supplemented cows), BS50 (50 mL of 10% A. nodosum), and BS100 (100 mL of 10% A. nodosum). In each cow, measurements of EME, dry matter intake (DMI), and milk yield (MY), as well as blood and milk sampling with respective analyzes, were performed before supplementation (P1), after 15 (P2) days, and after 30 (P3) days of supplementation. A. nodosum reduced (p < 0.05) methane production, methane yield, and methane intensity in both BS50 and BS100, and raised DMI (p < 0.05) only in BS50. Total bilirubin (p < 0.05) was higher in BS50 compared to CON cows in P2, and triacylglycerols were lower (p < 0.05) in BS50 than in CON cows in P3. Higher milk fat content was found in BS50 than in CON cows in P3. C16:0 proportions were higher (p < 0.05) in BS50 and BS100 than in CON cows, while C18:3n-3 was higher (p < 0.05) in BS100 than in BS50 and CON cows in P3. Dietary treatment with A. nodosum reduced EMEs and showed the potential to increase DMI and to improve energy status as well as milk composition in peak-lactating dairy cows.

Bio-based film development: Harnessing alginate and fucoidan extracted from Ascophyllum nodosum with glycerol and choline chloride-based solvent

Development of bioactive films and food coverings from renewable resources has major advantages for reducing reliance on plastic materials and increasing the shelf life of associated food products. This study assessed the development of such food covering films using combined alginate and fucoidan extracted from the brown seaweed Ascophyllum nodosum. A solvent containing glycerol and choline chloride was used to extract fucoidan before sodium carbonate was used for alginate extraction. The extracted fucoidan contained approximately 42.2% glycerol and was used as a substitution for glycerol when developing alginate films through 0, 50 and 100% glycerol supplementation. Two sets of films were produced using either crudely extracted or analytical grade alginate. These films were tested for suitability within food covering applications through tensile testing, moisture barrier analyses, antibacterial, and antioxidative assays. We show that glycerol supplementation with fucoidan had minimal effect on tensile properties at 50% glycerol supplementation, though it decreased significantly at 100% glycerol supplementation. Furthermore, the glycerol supplementation with fucoidan significantly reduced each film's moisture barrier properties, allowing for higher moisture transfer through the films. The re-addition of fucoidan into the alginate films also had little effect on the oxygen scavenging abilities of the films but maintained a substantial hydroxyl scavenging capacity of 48.09 ± 0.3% from crude alginate films with 100% glycerol supplementation when compared to 7.29 ± 3.42% neat alginate films without fucoidan supplementation. Our results show that combining alginate and fucoidan is an effective strategy to produce bioactive films for food coverings and facilitates solvent recycling, while reducing alginate polymer development costs.

Effect of polyphenols from Ascophyllum nodosum seaweeds on the rheology and digestion of corn starch gels and gluten-free bread features

The main objective of this work is to study the effect of polyphenols, from the brown seaweed Ascophyllum nodosum, on the structure and digestion behaviour of gels at two corn starch concentrations (1.95 and 5.00% w/w) as well as the structure, color and texture features of crumbs from gluten-free breads. Adsorption isotherms of polyphenols on native and gelled starches were carried out and modelled by means of Langmuir and Henry models, respectively. The formation and characteristics of tested gels were rheologically monitored by means of heating ramp, time sweep at high temperature, cooling ramp and frequency sweep at 25 °C. Elastic modulus values decreased with the presence of polyphenols. Additionally, the polyphenols significantly decreased the digestion rate, measured by both chemical and rheological procedures, and the final concentration of digested starch. Finally, the presence of polyphenols in breads increased the hardness and chewiness values and decreased the cohesiveness and resilience values as well as the crumb hardening during storage.

Fatty-Acid Profile of Extracts of the Brown Seaweed Ascophyllum nodosum

Fatty-Acid Profile of Extracts of the Brown Seaweed Ascophyllum nodosum

Impact of Foliar-Applied Plant Extracts on Growth, Physiological and Yield Attributes of the Potato (Solanum tuberosum L.)

The current reliance on pesticides and synthetic fertilizers has been vital to sustain and increase agricultural production. The continuous, excessive use of these traditional practices has negatively affected consumer health and burdened the ecosystem. The use of plant extracts as a tool to minimize agrochemical inputs has been extensively investigated; these extracts have the ability to improve both plant growth and agricultural productivity. Therefore, this study was conducted to determine the effect of foliar plant extract application on potato growth, as well as on certain physiological and yield attributes. From four weeks after planting onwards, five healthy, equal-sized potato plants per treatment received various foliar plant extract applications. These extracts included brown seaweed Ascophyllum nodosum extract (ANE), aloe vera leaf extract (AVE), garlic bulb extract (GBE), and moringa leaf extract (MLE). The treatments were repeated weekly until harvesting. Application data regarding growth and physiological parameters were collected weekly. The pre-harvest foliar application of various plant extracts significantly enhanced (p ≤ 0.05) the plant growth, physiological, and yield attributes of potatoes. The best growth and yield responses were observed following ANE and MLE application. Plant extracts have shown beneficial effects on other crops as well, but further validation of these effects is still necessary in order to popularize and commercialize such applications.

Evaluating taste preference of different sources of Ascophyllum nodosum meal in dairy heifers

We evaluated the supplementation of different sources of the brown seaweed Ascophyllum nodosum (ASCO) meal on taste preference in dairy heifers using a sequential elimination experiment. Six organic certified Jersey heifers averaging (mean ± SD) 16 ± 1.15 weeks of age and 92 ± 9.88 kg of body weight at the beginning of the study were used. Treatments consisted of a ground corn-based concentrate mash without seaweed supplementation (control), or this same concentrate mash supplemented with 57 g/d of ASCO meal obtained from Acadian Seaplants (Acadian Kelp), North American Kelp (SeaLife Kelp), or Thorvin Inc. (Thorvin for Animals). The experiment was conducted with 1 heifer enrolled at a time for 11 d each (n = 66 d total) with the feeding regimens distributed as follows: d 0–2 (adaptation phase), d 3–6 (feeding segment 1), d 7–9 (feeding segment 2), and d 10–11 (feeding segment 3). During the feeding segment 1 (d 3–6), the control diet was the most consumed treatment resulting in a total dry matter intake of 22.6 kg followed by Acadian, Thorvin, and Sealife with 17.7, 13.2, and 11.0 kg, respectively. However, Acadian was selected as the most preferred treatment during the feeding segment 1 for a total of 11 d, with control, Thorvin, and SeaLife totaling 8, 3, and 2 d, respectively. In the final ranking of treatments, when all 3 feeding segments were included in the evaluation, Acadian was selected as the first choice by 4 heifers with a ranking of 1.67 points, on a scale ranging from 1 (most preferred) to 4 (least preferred), followed by control (2.50 points), Thorvin (2.67 points), and Sealife (3.17 points). Overall, the treatments containing Acadian and SeaLife were the most and least preferred, respectively, indicating that heifers were able to distinguish different sources of the same seaweed species based on a taste preference sequential elimination experiment.

Effects of an Extract of the Brown Seaweed Ascophylum nodosum on Postprandial Glycaemic Control in Healthy Subjects: A Randomized Controlled Study.

The effects of the consumption of an extract of the brown seaweed Ascophyllum nodosum (BSW) on postprandial glucose and insulin responses to white bread were investigated in an acute, randomized, double-blind, three-arm, crossover, controlled trial in healthy, normoglycemic subjects. Sixteen subjects were administered either control white bread (50 g total digestible carbohydrates) or white bread with 500 mg or 1000 mg of BSW extract. Biochemical parameters were measured in venous blood over 3 h. Significant inter-individual variation in the glycaemic response to white bread was observed. Analysis of the responses of all subjects to either 500 mg or 1000 mg of BSW extract versus control revealed no significant effects of treatments. The variation in response to the control was used to classify individuals into glycaemic responders and non-responders. In the sub-cohort of 10 subjects with peak glucose levels after white bread above 1 mmol/L, we observed a significant decrease in maximum levels of plasma glucose after the intervention meal with 1000 mg of extract compared with the control. No adverse effects were reported. Further work is warranted to define all factors that determine "responders" to the effects of brown seaweed extracts and identify the cohort that would benefit the most from their consumption.

Plant Growth Promoting Properties of Four Arctic Seaweed Extracts

The objective of this study was to evaluate the effects of the White Sea brown seaweed Ascophyllum nodosum, Fucus vesiculosus, Laminaria digitata and Saccharina latissimi extracts on plant growth and biomass accumulation. Extracts were obtained by isopropanol maceration method. Growth promoting effects of all four seaweed extracts were observed at the initial growth phase of Triticum aestivum and Cucumis sativus plants. A. nodosum and F. vesiculosus extracts were more effective at medium concentrations (60, 120 and 300 mg/L) while higher concentration (1200 mg/L) decreased the growth rate and biomass accumulation in wheat plants, but not in cucumber seedlings when compared to control. Higher phenolic content in A. nodosum and F. vesiculosus extracts can possibly be a reason of lower effectiveness of extracts with high concentration. These results suggest that investigated arctic seaweeds have biostimulatory properties that affect plant growth and biomass accumulation and after intensive future studies can be exploited for elaboration of innovative products for agriculture.

Research Note: Effect of a phlorotannin extract of the brown seaweed Ascophyllum nodosum as a potential control strategy against Campylobacter in broilers

Poultry is generally recognized as the main source of human campylobacteriosis and Campylobacter is highly prevalent at the farm level. To reduce the relative risk of human campylobacteriosis attributable to broiler meat, it is necessary to reduce Campylobacter loads in broiler ceca but to date, no effective, reliable and practical strategy is available. The marine environment is a rich source of original natural compounds exhibiting different biological activities. The objective of this study was to test a phlorotannin extract of the brown seaweed Ascophyllum nodosum as a potential control strategy against Campylobacter in broilers. Bactericidal activity has been demonstrated in vitro, on several Campylobacter spp. strains at a range of 0.06 to 0.47 mg/mL. Therefore, an in vivo trial in experimental facilities was performed to evaluate addition of 0.2% (w/w) of an A. nodosum extract to feed distributed at the end of rearing from day 31 to day 35, and to assess the effect on artificial Campylobacter jejuni colonization. No statistical differences in Campylobacter enumeration were observed between the treated and control groups. Another trial was performed in a commercial broiler flock. Feed containing the extract at 0.2% (w/w) (2 kg/t) was distributed during the last 5 days of rearing (day 33–day 38). No significant effects on Campylobacter colonization and on growth parameters were observed compared to the control group. Additional studies are needed to assess whether active polyphenols are found in the cecum.

Polyesterase activities in bacterial isolates from seaweed and sponges, with potential utility in polyethylene terephthalate plastic and nanoparticle hydrolysis

Many marine bacteria have evolved to produce a range of extracellular enzymes which facilitate their growth and survival in the harsh, oligotrophic conditions often present in marine environments. Marine sponge derived Streptomycesstrains have previously been reported to produce polyesterase enzymes, which are of interest for several biotechnological applications, including polyethylene terephthalate (PET) plastic hydrolysis. Bacteria isolated from sponges and seaweed were screened for polyester hydrolysis activities using plate-clearing assays. Lipolytic and polyesterolytic activities were initially identified by employing tributyrin and polycaprolactone diol agar-based assay systems, respectively. Polyesterase activity was subsequently confirmed on both polycaprolactone and on PET-nanoparticle agar plates, resulting in the prioritisation of six isolates for Illumina next-generation genome sequencing. These include three Bacillusspp., isolated from the brown seaweed Ascophyllum nodosum,and from marine lake sponges Stelligera stuposaand Eurypon major, together with a Maribacterstrain again isolated from S. stuposa, and Brachybacteriumsp. and Micrococcussp. isolates of deep-sea sponges Pheronemasp. and Inflatella pellicula, that were sampled at depths of 2129m and 2900m, respectively. Genome mining and comparative genomic analysis of these isolates is currently underway to identify genes encoding the observed activities and to assess homology with known PET hydrolases. Microbes found living in association with filter-feeding sponges may have increased exposure to the plastics and microplastics that widely contaminate our marine ecosystems, thus representing a promising source of degradative activities towards synthetic polymers that could contribute to new plastic waste management strategies.

Marginal Impact of Brown Seaweed Ascophyllum nodosum and Fucus vesiculosus Extract on Metabolic and Inflammatory Response in Overweight and Obese Prediabetic Subjects.

The objective of the present study was to test whether a brown seaweed extract rich in polyphenols combined with a low-calorie diet would induce additional weight loss and improve blood glucose homeostasis in association with a metabolic and inflammatory response in overweight/obese prediabetic subjects. Fifty-six overweight/obese, dysglycemic, and insulin-resistant men and women completed a randomized, placebo-controlled, double-blind, and parallel clinical trial. Subjects were administrated 500 mg/d of either brown seaweed extract or placebo combined with individualized nutritional advice for moderate weight loss over a period of 12 weeks. Glycemic, anthropometric, blood pressure, heart rate, body composition, lipid profile, gut integrity, and oxidative and inflammatory markers were measured before and at the end of the trial. No effect was observed on blood glucose. We observed significant but small decreases in plasma C-peptide at 120 min during 2 h-OGTT (3218 ± 181 at pre-intervention vs. 2865 ± 186 pmol/L at post-intervention in the brown seaweed group; 3004 ± 199 at pre-intervention vs. 2954 ± 179 pmol/L at post-intervention in the placebo group; changes between the two groups, p = 0.002), heart rate (72 ± 10 at pre-intervention vs. 69 ± 9 (n/min) at post-intervention in the brown seaweed group; 68 ± 9 at pre-intervention vs. 68 ± 8 (n/min) at post-intervention in the placebo group; changes between the two groups, p = 0.01), and an inhibition in the increase of pro-inflammatory interleukin-6 (IL-6) (1.3 ± 0.7 at pre-intervention vs. 1.5 ± 0.7 pg/L at post-intervention in the brown seaweed group; 1.4 ± 1.1 at pre-intervention vs. 2.2 ± 1.6 pg/L at post-intervention in the placebo group; changes between the two groups, p = 0.02) following brown seaweed consumption compared with placebo in the context of moderate weight loss. Although consumption of brown seaweed extract had no effect on body weight or blood glucose, an early attenuation of the inflammatory response was observed in association with marginal changes in metabolic parameters related to the prevention of diabetes type 2.

Supplementation of Ascophyllum nodosum meal and monensin: Effects on diversity and relative abundance of ruminal bacterial taxa and the metabolism of iodine and arsenic in lactating dairy cows

Previous research has shown that the brown seaweed Ascophyllum nodosum (ASCO) has antimicrobial and antioxidant properties and also increases milk I concentration. We aimed to investigate the effects of supplementing ASCO meal or monensin (MON) on ruminal fermentation, diversity and relative abundance of ruminal bacterial taxa, metabolism of I and As, and blood concentrations of thyroid hormones, antioxidant enzymes, and cortisol in lactating dairy cows. Five multiparous ruminally cannulated Jersey cows averaging (mean ± standard deviation) 102 ± 15 d in milk and 450 ± 33 kg of body weight at the beginning of the study were used in a Latin square design with 28-d periods (21 d for diet adaptation and 7 d for data and sample collection). Cows were fed ad libitum a basal diet containing (dry matter basis) 65% forage as haylage and corn silage and 35% concentrate and were randomly assigned to 1 of the following 5 dietary treatments: 0, 57, 113, or 170 g/d of ASCO meal, or 300 mg/d of MON. Supplements were placed directly into the rumen once daily after the morning feeding. Diets had no effect on ruminal pH and NH3-N concentration, which averaged 6.02 and 6.86 mg/dL, respectively. Total volatile fatty acid concentration decreased linearly in cows fed incremental amounts of ASCO meal. Supplementation with ASCO meal did not change the ruminal molar proportions of volatile fatty acids apart from butyrate, which responded quadratically with the lowest values observed at 56 and 113 g/d of ASCO supplementation. Compared with the control diet or diets containing ASCO meal, cows fed MON showed greater molar proportion of propionate. Diets did not affect the α diversity indices Shannon, Simpson, and Fisher for ruminal bacteria. However, feeding incremental levels of ASCO meal linearly decreased the relative abundance of Tenericutes in ruminal fluid. Monensin increased the relative abundance of the CAG:352 bacterial genus in ruminal fluid compared with the control diet. Linear increases in response to ASCO meal supplementation were observed for the concentrations and output of I in serum, milk, urine, and feces. Fecal excretion of As increased linearly in cows fed varying amounts of ASCO meal, but ASCO did not affect the concentration and secretion of As in milk. The plasma activities of the antioxidant enzymes and the serum concentrations of thyroid hormones did not change. In contrast, circulating cortisol decreased linearly in diets containing ASCO meal. The apparent total-tract digestibilities of dry matter, organic matter, and crude protein increased linearly with ASCO meal, but those of neutral and acid detergent fiber were not affected. In summary, feeding incremental amounts of ASCO meal decreased serum cortisol concentration, and increased I concentrations and output in serum, milk, feces, and urine.

The Effect of an Engineered Biostimulant Derived from Ascophyllum nodosum on Grass Yield under a Reduced Nitrogen Regime in an Agronomic Setting

Nitrogen (N) is the most important macronutrient used in modern agricultural systems to enhance crop yields; however, a significant amount of applied N is not taken up by the crop and is lost to the environment. Improving the nitrogen use efficiency (NUE) of crops can curb these environmental losses while concurrently delivering economic gains. Plant biostimulants have potential to improve NUE in agronomic settings. In this research, a granular N-containing fertilizer coated with the biostimulant PSI-362, an extract from the brown seaweed Ascophyllum nodosum, was applied to grass managed under different production systems to assess its impact on NUE. The role of soil type, pH, phosphorus (P) and potassium (K) on the efficacy of the biostimulant in improving NUE was assessed using lysimeters filled with six different soils. A significant increase in grass yield (29%) was found with PSI-362 addition at a 75% N rate over the 75% N control (8478 kg of dry matter (DM) ha−1 vs. 6772 kg of DM ha−1) over two years of trials under a simulated grazing platform of six rotations. The NUE increased to 96.6% for the PSI-362-treated grass compared to 82.8% for controls. Field-based evaluations demonstrated no decrease in yield and quality from harvested and grazed grass treated with the biostimulant when the N rate was reduced by 20 to 25%. Based on these results, the application of PSI-362 allows a reduction in nitrogen input by up to 25% without losses of grass yield or quality.

Reducing Nitrogen Input in Barley Crops While Maintaining Yields Using an Engineered Biostimulant Derived From Ascophyllum nodosum to Enhance Nitrogen Use Efficiency.

Intensive agricultural production utilizes large amounts of nitrogen (N) mineral fertilizers that are applied to the soil to secure high crop yields. Unfortunately, up to 65% of this N fertilizer is not taken up by crops and is lost to the environment. To compensate these issues, growers usually apply more fertilizer than crops actually need, contributing significantly to N pollution and to GHG emissions. In order to combat the need for such large N inputs, a better understanding of nitrogen use efficiency (NUE) and agronomic solutions that increase NUE within crops is required. The application of biostimulants derived from extracts of the brown seaweed Ascophyllum nodosum has long been accepted by growers as a sustainable crop production input. However, little is known on how Ascophyllum nodosum extracts (ANEs) can influence mechanisms of N uptake and assimilation in crops to allow reduced N application. In this work, a significant increase in nitrate accumulation in Arabidopsis thaliana 6 days after applying the novel proprietary biostimulant PSI-362 was observed. Follow-up studies in barley crops revealed that PSI-362 increases NUE by 29.85–60.26% under 75% N input in multi-year field trials. When PSI-362 was incorporated as a coating to the granular N fertilizer calcium ammonium nitrate and applied to barley crop, a coordinated stimulation of N uptake and assimilation markers was observed. A key indicator of biostimulant performance was increased nitrate content in barley shoot tissue 22 days after N fertilizer application (+17.9–72.2%), that was associated with gene upregulation of root nitrate transporters (NRT1.1, NRT2.1, and NRT1.5). Simultaneously, PSI-362 coated fertilizer enhanced nitrate reductase and glutamine synthase activities, while higher content of free amino acids, soluble protein and photosynthetic pigments was measured. These biological changes at stem elongation stage were later translated into enhanced NUE traits in harvested grain. Overall, our results support the agronomic use of this engineered ANE that allowed a reduction in N fertilizer usage while maintaining or increasing crop yield. The data suggests that it can be part of the solution for the successful implementation of mitigation policies for water quality and GHG emissions from N fertilizer usage.

Seaweed extract to enhance marigold seed germination and seedling establishment

The brown seaweed Ascophyllum nodosum and seaweed-derived products have been widely used as nutrient additions, biofertilizer and biostimulant in horticultural crop systems. This study aimed to evaluate the effects of a seaweed extract obtained from whole brown algae (A nodosum) on seed germination and seedling growth of ornamental marigold (Tagetes erecta). The seeds of marigold were daily sprayed with 0 (control), 5, 10 or 15 mL L−1 commercial seaweed extract Acadian Seaplants™ (70 ml). The percentage, index and average time of seed germination, seedling height, fresh, dry mass of shoots, roots and root system morphology were evaluated. The results showed that the seaweed extract enhanced all parameters related to seed germination and seedling growth and development. The best results were obtained with 15 mL L−1 seaweed extract which increased by two-fold marigold seed germination and 84.00% seedling height, and both fresh and dry shoot mass and root morphology. We suggest algal extracts of Ascophyllum nodosum should be used as natural biostimulant on marigold crop, improving seed germination and seedling development.

Effects of Dietary Inclusion of Seaweed, Heat Stress and Genetic Strain on Performance, Plasma Biochemical and Hematological Parameters in Laying Hens.

Simple SummaryPrebiotics such as seaweeds have been proposed as positive influencers on hen health and productivity, including their response to stressors such as heat. The present study was undertaken to evaluate the effects of 3% red seaweed Chondrus crispus and 0.5% brown seaweed Ascophyllum nodosum supplements on the heat stress responses in two genetic strains of laying hens, Lohmann LSL-Lite (White) and Lohmann Brown-Lite (Brown). The short-term seaweed diet had little effect on blood characteristics, but long-term feeding affected several blood chemistry values. The seaweed supplement reduced the feed intake and improved the feed/egg efficiency in the short term, although did not consistently affect the long-term performance. Heat stress affected the leukocyte count and some plasma chemistry parameters, particularly in the Brown layer strain. Our results showed better production, feed efficiency and resistance to heat stress in the White layer strain, with significant liver enzyme changes in alkaline phosphatase (ALP), alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT). More research on the biological effects of seaweed supplementation is necessary to better understand its impacts on health and performance.This study was planned to investigate the effects of seaweed supplementation, genetic strain, heat stress and their interactions on laying hen performances, blood chemistry and hematology. In a short-term trial, laying hens of the two genetic lines Lohman LSL-Lite (White) and Lohman Brown-Lite (Brown) were supplemented with Chondrus crispus (CC) at 3% for 21 days, while a control group was not. In a long-term trial, the same two strains were assigned to control (0%), 3% red seaweed Chondrus crispus (CC) or 0.5% brown seaweed Ascophyllum nodosum (AN)-supplemented diets for 41 weeks, concluding with a four-week control or heat-stress period. The White hens displayed higher egg production and a lower feed/egg ratio. The short-term inclusion of CC significantly reduced the feed intake, weight gain and feed/egg ratio. The long-term seaweed intake affected the plasma albumin and gamma-glutamyl transferase (GGT) (p < 0.05), and there were significant strain-heat stress interactions; heat stress in the Brown birds was associated with reduced protein, globulin and glucose and increased cholesterol and GGT levels and higher heterophil-to-lymphocyte (H/L) ratios (p < 0.05) in response to heat stress (p < 0.05). In conclusion, a long-term seaweed supplementation affected the plasma protein and enzyme profiles, yet had little effect on hen leukocyte counts and the overall performance.

Ascophyllum nodosum Extract Biostimulant Processing and Its Impact on Enhancing Heat Stress Tolerance During Tomato Fruit Set.

The application of biostimulants derived from extracts of the brown seaweed Ascophyllum nodosum has long been accepted by growers to have productivity benefits in stressed crops. The impact of the processing method of the A. nodosum biomass is also known to affect compositional and physicochemical properties. However, the identification of the mechanisms by which processing parameters of Ascophyllum nodosum extracts (ANEs) affect biostimulant performance in abiotically stressed crops is still poorly understood. In this study, we performed a comparative analysis of two carbohydrate-rich formulations derived from A. nodosum: C129, an ANE obtained at low temperatures through a gentle extraction and the novel proprietary PSI-494 extracted under high temperatures and alkaline conditions. We tested the efficiency of both ANEs in unstressed conditions as well as in mitigating long-term moderate heat stress in tomato (Lycopersicon esculentum, cv. Micro Tom) during the reproductive stage. Both ANEs showed significant effects on flower development, pollen viability, and fruit production in both conditions. However, PSI-494 significantly surpassed the heat stress tolerance effect of C129, increasing fruit number by 86% compared to untreated plants growing under heat stress conditions. The variation in efficacy was associated with different molecular mass distribution profiles of the ANEs. Specific biochemical and transcriptional changes were observed with enhanced thermotolerance. PSI-494 was characterized as an ANE formulation with lower molecular weight constituents, which was associated with an accumulation of soluble sugars, and gene transcription of protective heat shock proteins (HSPs) in heat stressed tomato flowers before fertilization. These findings suggest that specialized ANE biostimulants targeting the negative effects of periods of heat stress during the important reproductive stage can lead to significant productivity gains.

On the efficacy of an Ascophyllum-based, soluble extract in association with standard plant growth regulators on the micropropagation of the agarophyte, Gracilaria blodgettii, from seaweed farms located at the northern entrance of the Panama Canal

Gracilaria spp. (agarophytes) are cultivated by Panamanian communities to use directly as food and as important components of traditional medicines and remedies. These uses are part of the traditional culture of both the Guna Indians and the Afro-Antillean communities. One driving force to better understand the biology of the various species of Gracilaria is their additional, commercial uses based on the agars they produce. In this study, we evaluated the effects of two commercial, soluble extract powders of the temperate, brown seaweed Ascophyllum nodosum (i.e., Ascophyllum marine plant extract powder—AMPEP), and one which had a boosted potassium level (designated as AMPEP K+). Each was evaluated for any micropropagation effects on the tropical red alga, Gracilaria blodgettii, in three independent experiments each of which lasted 45 days (the normal grow-out period). The phyco-stimulatory extracts were tested with and without association with standard plant growth regulators which are commonly used in micropropagation practices for higher plants. Growth was measured as a function of increased fresh weight and the number of newly emergent lateral shoots. This study demonstrated that vegetative propagules of G. blodgettii treated with AMPEP at 0.1 mg L−1 provided significant contributions to the successful and sustainable supply of vegetative propagules (“seedstock”). We suggest that the costs and quality of seedstock production can be significantly reduced over traditional methods, thereby contributing to the establishment of much-needed, viable marine farming practices in the Panamanian Caribbean.

Assessing the potential of milk iodine intake to mitigate iodine deficiency in pregnant women of the United States via supplementation of Ascophyllum nodosum meal to dairy cows: A sensitivity analysis

The brown seaweed Ascophyllum nodosum is known to bioaccumulate iodine (I). Previous research showed a linear relationship between A. nodosum meal (ASCO) intake and milk I concentration in dairy cows. Thus, improving milk I concentration by supplementation of ASCO to dairy cows may be a compelling strategy to naturally boost I intake in humans. A sensitivity analysis was conducted to gain insights regarding how different milk I intakes affect the I status of pregnant women relative to the United States Institute of Medicine (US IOM) recommended dietary allowance (RDA; 220 µg/d) and the World Health Organization (WHO) recommended nutrient intake (RNI; 250 µg/d) for I. Four studies in which dairy cows received various amounts of ASCO generated the milk I data set used in the sensitivity analysis. The annual per capita consumption of 2% reduced-fat milk in the United States, converted to daily intake (i.e., 0.26 cup; 1 cup = 236.6 mL), was used as the actual milk intake in the simulations. Five additional milk intake scenarios (2, 3, 4, and 5 times the actual per capita milk consumption and the 3 cups-equivalent recommended by the 2015-2020 Dietary Guidelines for American were also included in the sensitivity analysis with varying milk I concentrations (180, 765, and 483 µg/L). The 180, 765, and 483 µg/L values are milk I concentrations derived from cows not receiving ASCO or fed various amounts of ASCO in the diet or a single level (113 g/d) during the grazing season, respectively. With the actual United States milk per capita consumption of 0.26 cup/d and milk I concentrations of 180, 765, and 483 µg/L, 5.09, 21.7, and 13.6% of the RDA for I for pregnant women were met based on the US IOM, respectively. Similarly, 4.48, 19, and 12% of the RNI for I advised by the WHO was achieved with intake of 0.26 cup/d of milk containing I concentrations of 180, 765, and 483 µg/L, respectively. When 3 cups/d was included in the simulations, 58.2, 247, and 156% (US IOM), and 51.2, 217, and 137% (WHO) of the RDA or RNI for I required by gestating women was satisfied with milk I concentrations of 180, 765, and 483 µg/L, respectively. A regression analysis between I intake and milk I concentration revealed that 103 g/d of ASCO in the diet of dairy cows reached the maximum 500 µg/L threshold of I in milk recommended by the European Food Society Authority. Overall, milk from dairy cows fed ASCO can prevent I deficiency in pregnant women, but the amount of ASCO fed to cows needs to be fine-tuned to avoid excess I in milk. Further research is required to better understand the interactions between goitrogenic compounds from forages and concentrates and milk I concentration in cows fed ASCO. Research to evaluate the concentration of I in retail organic milk should be also conducted because of the high prevalence of ASCO fed in organic dairies in the United States.

A Biostimulant Preparation of Brown Seaweed Ascophyllum nodosum Suppresses Powdery Mildew of Strawberry.

Strawberry, an important fruit crop, is susceptible to a large number of pathogens that reduce fruit quality and productivity. In this study, the effect of a biostimulant prepared from Ascophyllum nodosum extract (ANE) (0.1%, 0.2%, and 0.3%) was evaluated on powdery mildew progression under greenhouse and field conditions. In the greenhouse, application of 0.2% ANE showed maximum reduction in powdery mildew progression as compared to the control. Forty-eight hour post-inoculation, foliar spray of 0.2% ANE reduced spore germination by 75%. Strawberry leaves sprayed with ANE showed higher total phenolic and flavonoid content in response to powdery mildew infection. Furthermore, application of ANE elicited defense response in strawberry plants by induction of defense-related enzymes, such as phenylalanine ammonia lyase, polyphenol oxidase, and peroxidase activity. In field conditions, foliar spray of 0.2% ANE showed a reduction of 37.2% of natural incidence of powdery mildew infection as compared to the control. ANE sprayed plant also reduces the severity of powdery mildew infection under natural conditions. These results indicate that application of ANE induces the strawberry plant’s active defense against powdery mildew infection by induction of secondary metabolism and regulating the activities of defense-related enzymes.