Brown Seaweed Extract Research Articles

Phytochemical analysis, antibacterial and anti-diabetic activity of three different seaweed extracts

Aim: Marine seaweed contains potential phytochemical compounds that could able to cure different health issues in humans naturally. Hence the research was aimed to investigate the antibacterial and in vitro anti-diabetic activity of three different seaweed extracts. Methods: Phytochemical compounds like phenol, flavonoids, tannins and alkaloids were quantitatively identified. Antibacterial activity of the seaweed extracts were determined against five different test bacteria. In vitro anti-diabetic activity of the extracts were investigated based on its inhibition effect on the alpha-amylase and alpha-glucosidase activity. Findings: Phytochemical analysis showed more phenolic and flavonoid content in green and brown seaweed extracts and lesser content in red seaweed extract. Antibacterial activity of green and brown seaweed extracts showed good inhibitory zones against all test bacteria ranging from 22.9 ± 0.57 mm to 24.9 ± 0.57 mm (green seaweed extract) and 17.9 ± 0.57 mm to 21.6 ± 0.75 mm (brown seaweed extract) respectively. In vitro anti-diabetic activity of seaweed on the inhibition of enzymes showed promising results. Among the three types, green seaweed extracts showed maximum inhibition of α-Amylase and α-glucosidase activity of 86.6 ± 0.76 % and 82.9 ± 0.57 % respectively. Conclusion: Findings showed that the phytochemicals present in the methanolic extract of seaweeds attribute positively for different pharmacological properties like antibacterial, anti-oxidant and anti-diabetic activity. Optimizing the production factors would able to commercialize the seaweeds in drug forms and could be used for the treatment of various diseases in humans.

Assessment of the conceivable inhibitory activity of pathogenic microorganisms extracted from seaweed using phytochemicals, antioxidants, and in-silico molecular dynamic simulation

Turbinaria ornata, Polycladia myrica, and Padina pavonica is a perennial Mediterranean-native seaweed that is commonly used for mass display. The principal aims of this reconnaissance were the isolation of various compounds from methanolic seaweeds extraction and screening the potential effect as antibacterial, and antioxidant. The micro-dilution method was used to measure antibacterial activity. Gas chromatography-mass spectrophotometry (GC. Mass) abused to analyze the chemical components of the methanolic seaweed extract. The existence of 19 secondary metabolites was discovered using GC–MS analysis: 8 different compounds for each seaweed's species. Among these bioactive compounds, 4 compounds from P. pavonica extract showed the binding affinity and ability to react with Beta-ketoacyl synthase (PDB ID 1EK4) of Escherichia coli. The phytocompounds' drug-like and poisonous characteristics were predicted. Auto Dock was used to examine the ligand receptor complexes' binding strength. T. ornate and P. pavonica had the highest activity against K. pneumonia, with 22.50 mm (0.78 µg/ml) and 22.23 mm (5.10 µg/ml) obtained, respectively. In a concentration-dependent manner, the extract components demonstrated substantial antioxidant activity. P. pavonica had the highest scavenging activity (78.00%, IC50 = 6.35 µg/ml), while ascorbic acid had a 96.45% scavenging impact. Because the chemicals bind to the Lipinski Ro5, they have drug-like characteristics. The compounds had no hepatotoxic effects. P. pavonica extract has the prospect of being used as a source of medicinal drug-like chemicals. The docking investigation found a strong correlation between the experimental results and the docking results. Finally, brown seaweed extract, particularly P. pavonica extract, demonstrated strong antibacterial, antioxidant, and free radical scavenging properties.

Oral administration of oligo fucoidan improves the survival rate, quality of life, and immunity in patients with lung cancer.

Lung cancer, the most commonly diagnosed cancer globally, has the highest incidence and mortality rates in Taiwan. It can be divided into two types. Non-small cell lung cancer (NSCLC) accounts for approximately 85% of lung cancers, which is further divided into adenocarcinoma, squamous cell carcinoma, and large cell lung cancer accounting for approximately 40%, 25%, and 15% of NSCLC cases, respectively. Small cell lung cancer accounts for approximately 15% of lung cancers. Early systemic therapy NSCLC was based on chemotherapy, and immunotherapy is currently under development. Fucoidan, from brown seaweed extracts, shows promise in mitigating radiation-induced lung fibrosis in animal studies, suggesting its potential as an adjuvant for radiation therapy-related lung fibrosis in lung cancer patients. However, the clinical utility of such adjuvant therapy in lung cancer treatment remains uncertain. The purpose of this study was to investigate the effects of oral administration of oligo-fucoidan on the survival rate, quality of life, and immunity of patients with lung cancer. Subjects with Non-small cell lung cancer aged between 20 and 80 were collected from outpatient clinics, divided into control group (n = 7): conventional therapy and fucoidan group (n = 13): received conventional therapy+ oral supplementation of oligo-fucoidan (550 mg × 4 tablets). Data were collected before the study, at weeks 4, 12, and 24 during the study, and to collect 20 ml of peripheral blood, for analysis biochemical data, liver and kidney function, lymphocyte population, inflammation cytokines, and using EORTC QLQ-C30 questionnaire to assess quality of life. The survival rates of the subjects in the control and fucoidan groups were 20% and 28.6%, respectively. During the study, patients in the fucoidan group experienced a better quality of life than those in the control group, but this difference lacked statistical significance. Oligo-fucoidan increases the CD19 lymphocyte population. The patients in the fucoidan group also had Lower inflammatory cytokine. Oligo-fucoidan holds promise as an adjuvant therapy to enhance the survival rate, quality of life, and immune function in patients with lung cancer.

Enhancement of root abscisic acid mediated osmotic regulation by macroalgal compounds promotes adaptability of rice (Oryza sativa L.) in response to progressive metal ion mediated environmental stress

Soil deterioration is a major cause of poor agricultural productivity, necessitating sufficient nutrient inputs like fertilizers and amendments for sustainable use. As one such strategy, the current study evaluates the potential of Sargassum wightii, a brown seaweed extract, as an osmopriming agent to improve seed germination, early establishment, and competent seedling performances in acidic soil. The elemental makeup of seaweed extract (BS) showed that it included major plant macro (Potassium, Nitrogen and Phosphorous), as well as micronutrients (Magnesium and Iron) and trace elements (Zinc, Copper, and Molybdenum). While seed germination was impacted by H+ ion toxicity, seeds primed with BS emerged earlier and showed a higher germination percentage (98.2%) and energy (92.4%). BS treatments enhanced seedling growth by 63% and had a positive effect on root growth (68.2%) as well as increases in root surface area (10%) and volume (67.01%). Stressed seedlings had 76.39% and 63.2% less carotenoid and chlorophyll, respectively. In seedlings treated with BS, an increase in protein and Total Soluble Sugars content of 14.56 and 7.19%, respectively, was seen. Fourier Transform-Infra Red analysis of postharvest soil indicated improved soil health with absorbance corresponding to enhanced soil water holding capacity and organic matter. Increased abscisic acid synthesis rate and associated antioxidant enzyme system (Malondialdehyde, Glutathione peroxidases and ascorbate peroxidase) activation, along with enhanced H+ adenosine triphosphate-ase and glutathione activities, help ameliorate and deport H+ ions from cells, scavenge Reactive Oxygen Species, thus protecting cells from injury. Seaweed extract successfully reduced H+-induced ion toxicities in rice by promoting their germination, physiological, metabolically, and growth parameters that could ultimately increase their productivity and yield in a sustainable and environmentally friendly manner.

The brown algae: Sargassum binderi sonder shows a potential nephroprotective activity in in-vivo experimental model

This study aimed to investigate the protective effect of ethanolic (EtOH) and water (H2O) extracts of brown seaweed named Sargassum binderi (S. binderi) against cisplatin (anticancer drug) - triggered nephrotoxicity. This drug is normally used for the treatment of solid tumors that causes acute kidney damage after assemblage in the renal tubules. It was an acute study, animals were divided into different groups randomly, cisplatin (7mg/kg i.p.) and normal saline were used as positive and negative control respectively. The EtOH and H2O extracts of S. bindari were given orally in a dose of 200mg/kg for 5 days to their respective groups. Nephroprotective and antioxidants potential of extracts were investigated in term of kidney and liver biomarkers, electrolytes, glucose & lipid profile along with reduced glutathione, catalase and malondialdehyde. GC-MS was performed to evaluate the presence of important therapeutic compounds in hexane extract of S.binderi. The EtOH and H2O extracts were found effective in decreasing the kidney and liver biomarkers with glucose and lipid profile, normalizing electrolytes which were disturbed by cisplatin and up-grading the antioxidant parameters by reducing the oxidative stress. GC-MS evaluation of hexane extract revealed the presence of 21 new compounds from S.binderi. Of which, 8-heptadecene, methyl tetradecanoate, 3,7,11,15-tetramethyl-2-hexadecen-1-ol, hexadecanoic acid, methyl ester were reported as antioxidant, anti-inflammatory, anti-diuretic and hypocholesterolemic compounds. S. binderi showed nephroprotective effect by stabilizing its associated biochemical parameters probably due to the antioxidant activity as confirmed by the presence of compounds.

Effect of Sargassum polycystum on Expression of Tyrosinase and Production of Melanin

Introduction: Melanogenesis, the process responsible for producing melanin pigment, hinges on the activation of the amino acid L-tyrosine by the pivotal enzyme tyrosinase. In cases of hyperpigmentation induced by ultraviolet radiation, there's a surge in both tyrosinase enzyme levels and melanin production. Sargassum polycystum is currently under active investigation for its potential in this regard. This review aims to delve deeper into the properties of Sargassum polycystum and its impact on tyrosinase expression and melanin production. Literature Review: Sargassum polycystum, a brown seaweed commonly found in coastal regions with abundant coral reefs, harbors active compounds like flavonoids, fucoidan, fucoxanthin, and phloroglucinol. Fucoidan, an extract from brown seaweed, exhibits promising anti-inflammatory and antioxidant properties. Recent studies have revealed its ability to impede the melanogenesis process. Specifically, it was observed that fucoidan from brown seaweed extract could dampen α-MSH stimulation while enhancing the activation of the ERK-MAPK pathway, thereby acting as a negative regulator for melanogenesis. Fucoxanthin, another component, showcases antioxidant capabilities. Furthermore, phloroglucinol, found in Sargassum polycystum, exerts tyrosinase inhibitory effects by chelating copper within the enzyme. Flavonoids like catechin, hesperidin, kaempferol, and baicalein in Sargassum polycystum demonstrate inhibitory effects on melanogenesis activation pathways, including suppression of the Erk1/2 pathway, MiTF, and direct inhibition of tyrosinase. Consequently, this leads to reduced tyrosinase expression and melanin production, ultimately attenuating the melanogenesis process. Conclusion: Sargassum polycystum emerges as a promising candidate for combating hyperpigmentation induced by exposure to ultraviolet B radiation.

Exploring the modulatory effects of brown seaweed meal and extracts on intestinal microbiota and morphology of broiler chickens challenged with heat stress

Brown seaweed (Ascophyllum nodosum) is known for its prebiotic roles and can improve animal intestinal health by enhancing the growth of beneficial microbes and inhibiting pathogenic ones. However, the gut health-modulatory roles of brown seaweed on chickens challenged with heat stress (HS) are rarely studied. The current study examined the effects of brown seaweed meal (SWM) and extract (SWE) on the ceca microbiota and small intestinal morphology of chickens challenged or unchallenged with HS. Three hundred and thirty-six 1-day-old Ross 308 broiler chicks were randomly assigned to either a thermoneutral (TN; 24 ± 1°C); or HS room (HS; 32-34°C, 8 h/d from d 21 to 27). All birds in each room were randomly allotted to 4 treatments - control (CON), CON + 1 mL/L seaweed extract (SWE) in drinking water, CON + 2 mL/L SWE in drinking water, and CON + 2% seaweed meal (SWM) in feed and raised for 28 d. On d 14 and 28, 12 and 24 birds per treatment group, respectively, were euthanized to collect the ceca content for gut microbiota analysis and small intestinal tissues for morphological examination. On d 14, 2% SWM increased (P = 0.047) the relative abundance of cecal Fecalibacterium and all brown seaweed treatments improved jejunal villus height (VH) and VH:CD compared to the CON diet. On d 28, HS significantly reduced (P < 0.05) ileal VH, VW, and VH:CD, and duodenal VH and VH:CD. Among the HS group, 2% SWM and 2 mL/L SWE significantly increased (P < 0.05) the relative abundance of Lactobacillus, Sellimonas, and Fournierella, compared to the CON diet. HS birds fed with 2% SWM had higher ileal VH and VH:CD compared to other treatments. In summary, SWM and SWE enhanced the abundance of beneficial microbes and improved small intestinal morphology among HS chickens. This implies that seaweed could potentially alleviate HS-induced intestinal impairment in chickens.

Bioefficacy Studies on Insecticidal Activities of Sargassum wightii with Neem oil against rice Leaf Folder, Cnaphalocrocis medinalis

The experiment was conducted to evaluate the insecticidal activity of solvent extracts of brown algal seaweed, Sargassum wightii and its combination with neem oil against rice leaf folder Cnaphalocrocis medinalis in the Department of Entomology, Faculty of Agriculture, Annamalai University, Tamil Nadu, India during 2022-2023. Seaweed extracts at 6, 7 and 8% concentrations alone and its combination with neem oil @ 0.5 and 1% concentrations were tested against rice leaf folder and compared to neem oil @ 1% as standard check. The combination treatment seaweed extract @ 8% + neem oil @ 1% resulted in the highest larval mortality of 80.00 percent. In seaweed extract @ 8% + neem oil @ 1%, the larva to adult conversion ratio was 1: 0.06 whereas in the untreated control, the ratio was 1:1.

GC-MS Spectrum of the Brown Alga, Turbinaria ornata (Turner) J Agardh and its Characterization of Bioactive Compounds

Seaweeds as a sustainable resource, possess numerous secondary metabolites which can alter insect metabolism, induce toxicity, modify growth, development and hinder their feeding activities. The purpose of the current study was to identify the bioactive compounds present in the acetone extract of brown algal seaweed, T. ornata and its biological activities. The phytochemical constituents were screened through Gas Chromatography and Mass Spectroscopy analysis which revealed the presence of 90 compounds that mostly comes under terpenoids, carboxylic acids, amino acids, saturated fatty acids, phenols and sesquiterpene at the retention time of 3.836, 7.398, 8.765, 15.897, 26.113, 31.636, 34.085, 35.276, 36.528 and 39.943. The identified compounds were likely to possess various biological activities such as antifungal, antibacterial, antioxidant and novel insecticidal properties proved its potential use in integrated pest management strategies in the future.

Simple and Rapid Voltammetric Method Using a Gold Microwire Electrode to Measure Inorganic Arsenic in Holopelagic Sargassum (Fucales, Phaeophyceae)

The valorization of massive strandings of holopelagic Sargassum spp. is strongly limited by high levels of inorganic arsenic (Asi) that are potentially above the limit of current regulations. Monitoring Asi in algal biomass is currently achieved using standard chromatographic separation followed by spectroscopic detection. Here, we propose an alternative simpler procedure based on the extraction of Asi from the freeze-dried algal powder in deionized water and the electroanalytical detection of the diluted extract at a gold-microwire electrode. The protocol was optimized both in terms of extraction (powder/water ratio, extraction time, temperature) and electrolyte used for the voltammetric detection. Two electrolytes were tested: one composed of citric acid, sulfamic acid and KCl (pH 2.0) and another composed of an acetate buffer (pH 4.7) and NaCl. We demonstrate here that Asi determination is possible with the first electrolyte but it is necessary to deal with a relative unstable signal. Measurement of Asi was best achieved with the second electrolyte (acetate buffer and NaCl) with the following optimized electrochemical conditions: deposition potential of −1.2 V, deposition time of 30 seconds and linear scan voltammetry. Voltammetric results were then compared to a reference method (HPLC-ICP-MS) using different morphotypes of holopelagic Sargassum spp. (S. natans VIII, S. natans I and S. fluitans III), using commercial extracts of brown seaweeds and using a Hijiki certified reference material. Very good agreement was obtained between our novel method and HPLC-ICP-MS. Both methods show that inorganic arsenic is almost entirely present as As(V) in Sargassum spp. extracts.

8 Investigating the Effects of an Omega-3 rich Brown Seaweed Extract on Atopic Dermatitis in a Keratinocytes Raft Model

8 Investigating the Effects of an Omega-3 rich Brown Seaweed Extract on Atopic Dermatitis in a Keratinocytes Raft Model

Influence of Brown Seaweed (Ecklonia maxima) Extract on the Morpho-Physiological Parameters of Melon, Cucumber, and Tomato Plants

In this study, we evaluated the impact of brown seaweed extract (Ecklonia maxima) on the morphology and physiology of three different plant species. We conducted experiments using two types of fertilizers: an artificial fertilizer (0.1 g/L) and a biological extract of brown seaweed (Ecklonia maxima) at two concentrations (C1 at 1 mL/L and C2 at 2.5 mL/L). For melon, the application of C1 resulted in significant improvements in photosynthesis parameters, total chlorophyll content, and overall plant growth. When C2 was applied, it further enhanced these parameters, leading to a notable increase in shoot phytomass. In the case of cucumber, C1 led to increased resource allocation towards stems and leaves. Conversely, C2 increased the number of green leaves and contributed to higher shoot phytomass. For tomato plants, the application of C1 resulted in a slight increase in photosynthesis, but it did not significantly impact leaf growth. On the other hand, C2 induced a modest increase in photosynthesis, chlorophyll content, and root growth. In summary, our findings indicate that brown seaweed extract has a discernible influence on the physiology of the studied plants. However, the specific effects on resource allocation largely depend on the plant species and the concentration of the extract applied.

Effect of Soaking Time for Eggs with Brown Seaweed Extract (Sargassum Crassifolium) for Purebred Chicken Eggs

The main objective of this study was to investigate how different durations of soaking brown seaweed extract (Sargassum crassifolium) affect the quality of chicken eggs in terms of their safety and sensory characteristics. The research utilized an experimental design with a one-factor Completely Randomized Design, encompassing five different time intervals: 0 minutes, 30 minutes, 40 minutes, 50 minutes, 60 minutes, and 70 minutes of soaking the eggs in S. crassifolium extract, each with three replications. The parameters that were assessed included the microbiological quality, specifically the total microbe count, APM coliform count, APM E. coli count, and the presence of Salmonella sp. Additionally, the organoleptic quality, focusing on the appearance and aroma of the eggs, was also evaluated. The collected data was subjected to a variance analysis (Analysis of Variance) at a significance level of 5%, using CoStat software. In cases where a significant difference was detected, post-hoc tests such as the least significant difference (LSD) for the total microbial parameters and the Honest Significant Difference (BNJ) for the organoleptic parameters were performed to identify specific variations among the different soaking time intervals. The results of the study demonstrated that an extended soaking time of 70 minutes in S. crassifolium extract had a notable impact. It significantly reduced the total microbial count on the eggshells by 5.5671 Log CFU per shell, lowered the coliform count to 11.07 APM per shell, resulted in an E. coli count below 3.0 APM per shell, and effectively eliminated Salmonella sp.

Foliar application of Ascophyllum nodosum on improvement of photosynthesis, fruit setting percentage, yield and quality of tomato (Solanum lycopersicum L.)

In recent days, liquid formulations of brown seaweed extract, Ascophyllum nodosum used as a biostimulant in agriculture. Various studies suggest that A. nodosum enhanced the growth and yield of agriculturally important crops, but still, there is a lack of information about the biostimulation effects on photosynthesis, flowering and fruit setting of tomato. Hence, the present study aimed to know the effect of foliar application of A. nodosum on photosynthesis, flowering, fruit setting, yield and quality of tomato. A biostimulant product, MC Set with A. nodosum extract applied to tomato as a foliar spray at rates of three different concentrations such as 1.0 L ha−1 (MS 1), 2.0 L ha−1 (MS 2), 3.0 L ha−1 (MS 3) for six times during flowering of 2nd (30 Days after transplanting – DAT), 3rd (40 DAT) and 4th (50 DAT) cluster and fruit setting of 2nd (60 DAT), 3rd (70 DAT) and 4th (80 DAT) cluster respectively. The MC Set treatments enhanced the plant photosynthesis, flower number and fruit number per cluster, yield and quality traits of tomato. However, the middle concentration MS 2 showed highest photosynthetic rate, stomatal conductance, SPAD value, flower and fruit in 2nd, 3rd and 4th cluster. It also had better average fruit weight and yield per plant and hectare and enhanced the quality parameters such as total soluble solids, ascorbic acid content, lycopene and total sugars compared to control and other two concentrations of MS Set. Hence, using A. nodosum extract on tomato growth could be a better sustainable crop production method.

Transcriptomic and physiological approaches to decipher cold stress mitigation exerted by brown-seaweed extract application in tomato.

Chilling temperatures represent a challenge for crop species originating from warm geographical areas. In this situation, biostimulants serve as an eco-friendly resource to mitigate cold stress in crops. Tomato (Solanum lycopersicum L.) is an economically important vegetable crop, but quite sensitive to cold stress, which it encounters in both open field and greenhouse settings. In this study, the biostimulant effect of a brown-seaweed extract (BSE) has been evaluated in tomato exposed to low temperature. To assess the product effects, physiological and molecular characterizations were conducted. Under cold stress conditions, stomatal conductance, net photosynthesis, and yield were significantly (p ≤ 0.05) higher in BSE-treated plants compared to the untreated ones. A global transcriptomic survey after BSE application revealed the impact of the BSE treatment on genes leading to key responses to cold stress. This was highlighted by the significantly enriched GO categories relative to proline (GO:0006560), flavonoids (GO:0009812, GO:0009813), and chlorophyll (GO:0015994). Molecular data were integrated by biochemical analysis showing that the BSE treatment causes greater proline, polyphenols, flavonoids, tannins, and carotenoids contents.The study highlighted the role of antioxidant molecules to enhance tomato tolerance to low temperature mediated by BSE-based biostimulant.

Effects of extracting solvents on phytochemical, antioxidant, and antibacterial activity of some seaweeds from the Bay of Bengal offshore Island

Seaweed is a rich source of bioactive compounds. Therefore, searching of natural antioxidant and antibacterial agents as alternatives to a synthetic counterpart is of great interest. The effects of various extracting solvents (viz. methanol, ethanol, and acetone) on the phytochemical content, antioxidant, and antibacterial activity of seven seaweeds consisting of three brown seaweeds (Sargassum natans, Sargassum fluitans, Spatoglossum asperum), three red seaweeds (Hypnea pannosa, Hypnea musciformes, Porphyra linearis) and one green seaweed (Ulva lactuca) were evaluated. The antioxidant capacity of crude extracts was evaluated by total antioxidant activity (TAA), 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2, 2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and cupric reducing antioxidant capacity (CUPRAC) assays. Seaweed extracts were also tested against Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa by agar well diffusion method. The total phenolic content (TPC) of seaweed extracts varied significantly (P < 0.05) ranging from 51.08 ± 0.72–74.62 ± 1.15 mg GAE/g. Methanolic extracts of S. natans showed significantly the highest TPC, total flavonoid content (79.22 ± 5.21 mg QE/g), and TAA (57.79 ± 4.35 mg AA/g) than other seaweed extracts. Methanolic extracts of S. natans also exhibited the highest DPPH and ABTS radical scavenging effects (EC50 = 0.74 ± 0.04 and 0.14 ± 0.01 mg/ml, respectively). While, methanolic and ethanolic extracts of S. natans showed significantly the highest effective concentration (ECA0.50) value (0.19 ± 0.02 mg/ml and 0.14 ± 0.02 mg/ml, respectively) of CUPRAC. Pearson's correlation test and principal component analysis showed the relation between TPC and various antioxidant activity assays of seaweed extracts. The seaweed methanolic extracts showed a comparatively higher zone of inhibition against all the bacterial strains than other solvent extracts. However, all the solvent extracts of U. lactuca were almost inactive against all the bacterial strains. The results of this study demonstrated that methanolic extracts of brown seaweeds showed comparatively better antioxidant and antibacterial activity, which could be used in the food and pharmaceutical applications.

Anti-skin glycation and collagen level stimulation of brown seaweed extracts and their compositional characteristics

This study aimed to investigate anti-skin aging potential of the extracts from three Southern Australian brown seaweeds: Ecklonia radiata (ER), Cystophora moniliformis (CM), and Cystophora siliquosa (CS). These extracts and two positive controls (Aminoguanidine (AG), a drug candidate for anti-glycation, and phloroglucinol (PG)) were tested for their inhibition of glycation reaction using in vitro non-cellular bovine serum albumin (BSA)-glucose and methylglyoxal (MGO) models. The safe doses were also established by toxicity test with human skin fibroblast cell by MTT assay. Among three extracts studied, ER showed the highest toxic, but far less than both positive controls. The CM and CS extracts at 500 μg/mL showed inhibition of glycation activity, approximately 65–90 % compared to AG (15–40 %) and PG (15–20 %) at 20 μg/mL. In addition, the stimulation of collagen and elastin levels using an in vitro cell-based assay was evaluated. Relative to the control (water without samples), the CM and CS extracts at concentration greater than or equal to 250 μg/mL significantly increased the collagen levels of human skin fibroblast cells up to ∼16.5 folds, while there was no significant increase in elastin levels by most seaweed extracts. Furthermore, compositions of all extracts were characterized. Apart from high polysaccharide contents, phlorotannin which accounts for 17–23 % of CM and CS might be responsible for their anti-skin aging benefits. These findings demonstrate that the brown seaweed extracts CM and CS have high potential to be used as skin anti-aging supplements with anti-glycation and collagen stimulation benefits, worthy of further in vivo studies.

Insecticidal activity of brown seaweed (Sargassum latifolium) extract as potential chitin synthase inhibitors: Toxicokinetic and molecular docking approaches

In this study, Sargassum latifolium (S. latifolium) n-hexane extract as a novel source for insecticidal bioactive compounds was investigated. The composition of the extract was identified by using GC-MS analysis. We performed the study on four types of insects and larvae sp (Sarcophaga bullata, Tribolium castaneum, Musca domestica, and Solenopsis invicta) which cause a deleterious impact on the crops and human health. We used scanning electron microscopy to show the destructive effects of S. latifolium extract on the exoskeleton. The treatment exhibited severe morphological changes and a high mortality rate. Also, different bioinformatic approaches were utilized to investigate the possible insecticidal mechanism of the extract. Molecular docking showed the potential of the compounds to be chitin synthase inhibitors. Besides, the toxicokinetic parameters of the most promising compounds were evaluated to assess the impact of using the extract as an insecticidal agent on human health. S. latifolium extract exhibited promising insecticidal activity and acceptable toxicokinetic properties as compared to other known pesticide groups.

Activation of Liver X Receptors and Peroxisome Proliferator-Activated Receptors by Lipid Extracts of Brown Seaweeds: A Potential Application in Alzheimer's Disease?

The nuclear liver X receptors (LXRα/β) and peroxisome proliferator-activated receptors (PPARα/γ) are involved in the regulation of multiple biological processes, including lipid metabolism and inflammation. The activation of these receptors has been found to have neuroprotective effects, making them interesting therapeutic targets for neurodegenerative disorders such as Alzheimer's Disease (AD). The Asian brown seaweed Sargassum fusiforme contains both LXR-activating (oxy)phytosterols and PPAR-activating fatty acids. We have previously shown that dietary supplementation with lipid extracts of Sargassum fusiforme prevents disease progression in a mouse model of AD, without inducing adverse effects associated with synthetic pan-LXR agonists. We now determined the LXRα/β- and PPARα/γ-activating capacity of lipid extracts of six European brown seaweed species (Alaria esculenta, Ascophyllum nodosum, Fucus vesiculosus, Himanthalia elongata, Saccharina latissima, and Sargassum muticum) and the Asian seaweed Sargassum fusiforme using a dual luciferase reporter assay. We analyzed the sterol and fatty acid profiles of the extracts by GC-MS and UPLC MS/MS, respectively, and determined their effects on the expression of LXR and PPAR target genes in several cell lines using quantitative PCR. All extracts were found to activate LXRs, with the Himanthalia elongata extract showing the most pronounced efficacy, comparable to Sargassum fusiforme, for LXR activation and transcriptional regulation of LXR-target genes. Extracts of Alaria esculenta, Fucus vesiculosus, and Saccharina latissima showed the highest capacity to activate PPARα, while extracts of Alaria esculenta, Ascophyllum nodosum, Fucus vesiculosus, and Sargassum muticum showed the highest capacity to activate PPARγ, comparable to Sargassum fusiforme extract. In CCF-STTG1 astrocytoma cells, all extracts induced expression of cholesterol efflux genes (ABCG1, ABCA1, and APOE) and suppressed expression of cholesterol and fatty acid synthesis genes (DHCR7, DHCR24, HMGCR and SREBF2, and SREBF1, ACACA, SCD1 and FASN, respectively). Our data show that lipophilic fractions of European brown seaweeds activate LXRs and PPARs and thereby modulate lipid metabolism. These results support the potential of brown seaweeds in the prevention and/or treatment of neurodegenerative diseases and possibly cardiometabolic and inflammatory diseases via concurrent activation of LXRs and PPARs.

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.