Composition Of Seaweeds Research Articles

Detailed lipid investigation of edible seaweeds by photochemical derivatization and untargeted lipidomics.

Seaweeds are macrophytic algae that have been gaining interest as alternative healthy foods, renewable drug sources, and climate change mitigation agents. In terms of their nutritional value, seaweeds are renowned for their high content of biologically active polyunsaturated fatty acids. However, little is known about the regiochemistry-the geometry and position of carbon-carbon double bonds-of free and conjugated fatty acids in seaweeds. In the present work, a detailed characterization of the seaweed lipidome was achieved based on untargeted HRMS-based analysis and lipid derivatization with a photochemical aza-Paternò-Büchi reaction. A triple-data processing strategy was carried out to achieve high structural detail on the seaweed lipidome, i.e., (i) a first data processing workflow with all samples for aligning peak and statistical analysis that led to the definition of lipid sum compositions (e.g., phosphatidylglycerol (PG) 34:1), (ii) a second data processing workflow in which the samples of each seaweed were processed separately to annotate molecular lipids with known fatty acyl isomerism (e.g., PG 16:0_18:1), and (iii) the annotation of lipid regioisomers following MS/MS annotation of the lipid derivatives obtained following the aza-Paternò-Büchi reaction(e.g., PG 16:0_18:1 ω-9). Once the platform was set up, the lipid extracts from 8 seaweed species from different seaweed families were characterized, describing over 900 different lipid species, and information on the regiochemistry of carbon-carbon double bonds uncovered unknown peculiarities of seaweeds belonging to different families. The overall analytical approach helped to fill a gap in the knowledge of the nutritional composition of seaweeds.

Profile of inorganic elements of seaweed from the Brazilian Northeast coast

The contents of 24 elements were determined in seven species of macroalgae collected in Ceara-Brazil, in the rainy and dry seasons of 2022. The samples were digested, and the analytes were quantified by ICP-OES and Hg by direct analyzer. The CRM CD-200 was analyzed for accuracy and obtained recoveries were higher than 95 %. The seaweed species have different inorganic element profiles with predominant elements being: Ca, K, Na, Mg and P. The Sargassum vulgare species stood out for its Hg and As contents (1.479 ± 0.005 mg kg−1 and 172 ± 6 mg kg−1, both in the rainy seasons). Ulva lactuca attracted attention for its high concentration of V (46.4 ± 3.4 mg kg−1, rainy season). In general, the elemental content levels in the macroalgae samples were higher in the rainy season. Long-term studies to comprehend the effect of seasonality on the elemental composition of seaweed must be carried out.

Ocean acidification significantly alters the trace element content of the kelp, Saccharina latissima

Seaweeds are ecosystem engineers that can serve as habitat, sequester carbon, buffer ecosystems against acidification, and, in an aquaculture setting, represent an important food source. One health issue regarding the consumption of seaweeds and specifically, kelp, is the accumulation of some trace elements of concern within tissues. As atmospheric CO2 concentrations rise, and global oceans acidify, the concentrations of elements in seawater and kelp may change. Here, we cultivated the sugar kelp, Saccharina latissima under ambient (~400 μatm) and elevated pCO2 (600–2400 μatm) conditions and examined the accumulation of trace elements using x-ray powder diffraction, sub-micron resolution x-ray imaging, and inductively coupled plasma mass spectrometry. Exposure of S. latissima to higher concentrations of pCO2 and lower pH caused a significant increase (p < 0.05) in the iodine and arsenic content of kelp along with increased subcellular heterogeneity of these two elements as well as bromine. The iodine-to‑calcium and bromine-to‑calcium ratios of kelp also increased significantly under high CO2/low pH (p < 0.05). In contrast, high CO2/low pH significantly reduced levels of copper and cadmium in kelp tissue (p < 0.05) and there were significant inverse correlations between concentrations of pCO2 and concentrations of cadmium and copper in kelp (p < 0.05). Changes in copper and cadmium levels in kelp were counter to expected changes in their free ionic concentrations in seawater, suggesting that the influence of low pH on algal physiology was an important control on the elemental content of kelp. Collectively, these findings reveal the complex effects of ocean acidification on the elemental composition of seaweeds and indicate that the elemental content of seaweeds used as food must be carefully monitored as climate change accelerates this century.

Fatty Acid and Amino Acid Composition of Seaweed Collected from Rameshwaram, Southeast Coast of India

Fatty Acid and Amino Acid Composition of Seaweed Collected from Rameshwaram, Southeast Coast of India

Harnessing the power of seaweed: unveiling the potential of marine algae in drug discovery

Seaweeds, also known as marine algae, have gained attention as a promising source of bioactive compounds with potential applications in drug discovery. This review explores the emerging field of seaweed-based drug discovery and highlights the diverse range of bioactive compounds found in seaweeds, including polysaccharides, phlorotannins, pigments, and peptides. These compounds exhibit various pharmacological activities such as antioxidant, anti-inflammatory, antimicrobial, antiviral, and anticancer effects. Seaweeds have demonstrated particular promise in the areas of cancer research, with certain species showing potent antitumor properties. Additionally, their anti-inflammatory, antimicrobial, and neuroprotective potential has captured scientific interest in the treatment of chronic diseases and neurodegenerative disorders. However, challenges related to compound identification, extraction methods, scalability of seaweed cultivation, and understanding the mechanisms of action still need to be addressed. As researchers employ advanced technologies and dive deeper into the chemical composition of seaweeds, the untapped potential of these marine organisms in drug discovery awaits further exploration and holds significant promise for future therapeutic advancements.

Vitamin content in seaweeds: A systematic review on water-soluble and fat-soluble vitamins for adult daily intake

Background:With the global population on the rise, there is a growing imperative for scientists to innovate new foods utilizing the Earth's resources, catering to consumer preferences, and promoting health benefits. There is a claim that algae, particularly seaweeds, represent an exceptional source of vitamins. Seaweeds, belonging to the marine algae category, harbor potential functional compounds targeted at mitigating metabolic risk factors. They can be integrated into food and beverage preparation either as a whole plant or as extracts. Despite assertions regarding seaweed's vitamin richness, this aspect remains unverified in humans.Objectives:This study aims to undertake a comprehensive literature review to evaluate the amount of water-soluble and fat-soluble vitamins in seaweeds, with a specific focus on vitamins B12, C, and Carotenoids.Methods:A comprehensive search for full-text, English-only publications was conducted on PubMed and Google Scholar, covering the period from 2016 to 2022. Two search terms were employed on PubMed, yielding 7 and 781 studies, respectively. From these, three studies met the pre-determined eligibility criteria for inclusion. On Google Scholar, the search generated 17,100 studies, and after screening, two studies met the eligibility criteria out of sixty. In total, five relevant publications were identified. The composition of seaweeds was then compared to other dietary sources and nutritional intakes.Results: Seaweeds prove to be a superior source of vitamin C compared to iceberg lettuce, although not abundant for food consumption. They serve as an alternative source of vitamin B12 for the vegetarian population, and Vitamin A (carotenoids) found in seaweeds surpasses that in carrots. The vitamin A content ranges from 2–10% of Reference Nutrient Intake (RNI), while vitamin C content varies from 1–23% of RNI, and vitamin B12 content varies from 107–446% of RNI. Seaweeds exhibit substantial potential as food supplements and as ingredients in the food industry, providing a noteworthy amount of nutritional value.Conclusions: Seaweeds have the potential to enhance daily vitamin intake, particularly for vitamin B12, C, and Carotenoids, in comparison to the recommended dietary allowance.Keywords: Seaweeds, Algae, Marine Algae, Vitamins, Vitamin C

Chemical composition of seaweed and its medical-biological properties

RELEVANCE. Seaweed, along with all the other aquatic biological resources, is of great economic importance for all countries of the world community. Due to positive effects of biologically active substances, contained therein, it is widely used as dietary supplements, drugs, hydrocolloids (agar, alginates, carrageenan).&#x0D; OBJECTIVE. Based on literature data to study current knowledge about the chemical composition of seaweed and its medical-biological properties, which can be used in life activity.&#x0D; MATERIALS AND METHODS. The study used literature sources from international databases Web of Science, Scopus as well as the national library system eLibrary. The keywords in the search engine: seaweed, biochemical composition, biologically active properties, medical importance.&#x0D; RESULTS. The chemical composition of seaweed is due to its habitat. It contains practically all chemical elements, present in seawater. Because of beneficial biological effects, seaweed is widely used by humans, especially in medicine. Among organic compounds seaweed is rich in polysaccharides, lipids, protein compounds as well as vitamins. The main part of polysaccharides belongs to alginic acid and fucoidan. Alginates have anti-inflammatory, sorption and reparative properties, normalize metabolism. Fucoidans have anticoagulant and antioxidant effect, inhibit penetration of viruses into tissue cells.&#x0D; DISCUSSION. Seaweed is rich in protein compounds. It contains all essential amino acids. Moreover, all classes of fatty acid (especially polyunsaturated) are found in seaweed. Lastly, many water-soluble and fat-soluble vitamins are synthesized in seaweed, like plants on land: ascorbic acid, tocopherols, carotenes, thiamine, cobalamins, etc.&#x0D; It is concluded that seaweed can be considered a unique supplier of biologically active components: minerals, proteins, polysaccharides, polyunsaturated fats and vitamins. Its use is justified with therapeutic and preventive purposes.

Biocompounds from Green Algae of Romanian Black Sea Coast as Potential Nutraceuticals

Three green algae, collected from the Romanian Black Sea coast, are studied: Ulva lactuca, Enteromorpha intestinalis, and Cladophora vagabunda, which were collected from six different coastal areas. This paper aims to identify the bioactive compounds of these green algae and their beneficial properties, in order to use them as potential nutraceuticals using different analytical methods. Pharmacognostic, microbiological, and physico-chemical methods used for the analysis of algal materials revealed a rich and diverse array of biocompounds with nutritional value. In the case of green algae, a high percentage of sulphates, carbohydrates and dietary fibers were identified. Moisture, ash, total nitrogen, protein and lipid contents were determined. The contents of pigments, vitamins, and metals determined complement the nutritional qualities of the three seaweed species studied as future nutraceuticals. The content of flavonoid and phenolic compounds identified in the composition of seaweeds justifies their antioxidant and antimicrobial properties. The antioxidant capacity was tested by means of DPPH, reducing power, and TEAC methods, and the algae studied exhibit important antioxidant properties that can be used to enhance their potential as nutraceuticals. The studied algae show good antibacterial activity on both Gram (+) and Gram (−) bacteria, with slightly better activity on Gram (−) bacteria. Biocompounds from green algae from the Black Sea coast may represent an important source of marine nutraceuticals with medical and nutritional potential.

Mineral composition of seaweeds and seagrasses of the Philippines

ABSTRACT Minerals, although required in relatively small amounts, play crucial roles in many vital processes of the human body, and their deficiency can cause several serious health issues. Seaweeds and seagrasses, traditionally consumed as vegetables in coastal areas worldwide, are generally known as a rich source of macro- and microminerals in concentrations much higher than in terrestrial plants. Despite their significant nutritional potential, the mineral composition of most of the seaweeds and seagrasses remains unexplored. In the present study, the concentrations of 23 minerals in nine seaweeds and seagrasses from the Philippines were determined using inductively coupled plasma optical emission spectroscopy. The results showed that some of the species are excellent sources of various essential minerals. Actinotrichia fragilis and Mastophora rosea were the highest in calcium content (21,511 and 14,100 mg/100 g DM, respectively), and, together with Anadyomene plicata, they were richest in copper (2.49–3.77 mg/100 g DM), iron (292–480 mg/100 g DM), manganese (22.3–27.2 mg/100 g DM), and nickel (1.49–2.93 mg/100 g DM). Moreover, M. rosea had the highest content of magnesium (2,093 mg/100 g DM). Other species, such as Enhalus acoroides (phosphorus in flowers and seeds, 277 and 282 mg/100 g DM, respectively), Halophila ovalis (silicon, 13.8 mg/100 g DM), Halymenia dilatata (zinc, 5.51 mg/100 g DM), Halymenia maculata (sulphur, 8,268 mg/100 g DM) and Portieria hornemannii (potassium, 8,985 mg/100 g DM; vanadium, 2.90 mg/100 g DM) can be highlighted as good sources of minerals. All these species have a promising potential as mineral-rich foods and can contribute to food and nutrition security.

Distribution and Biochemical Composition of Seaweeds in relation to Hydro-chemical Characters of Marine Water

The aim of this study was to determine the distribution pattern, pigments and biochemical composition of various seaweed species collected from the Gopnath coast in Gujarat, India from August 2021 to December 2021 as well as to examine physico-chemical variables in marine waters. Besides, the relationship between the pigment, biochemical content of seaweed species and hydrochemical characters was also investigated with principal component analysis (PCA). There are total of nine species with the highest number of Chlorophyta species. During the investigation period, the distribution and occurrence of the species changed greatly. Results indicate that the chlorophyta had the highest chlorophyll content, on the other hand carotenoids were found greater in Rhodophyta members. According to a statistical analysis (Correlation) computed among environmental parameters and pigment, it was observed that the chlorophyll content was positively correlated with pH, salinity and hardness whereas carotenoid shows positive correlation with temperature and dissolved oxygen of selected site. Moreover, the principal component analysis shows that the pH, electrical conductivity (EC), salinity, hardness and alkalinity are the main factor for marine water quality whereas principal component analysis of metabolites of seaweed shows that the carbohydrate and amino acids are the main principal components of Chlorophyta species. Protein is the main principal component of Rhodophyta specie. Based on the results obtained, we can conclude that the hydro-chemical characters may play a role in the biosynthetic pathways of seaweed.

Fucoidan from Fucus vesiculosus: Evaluation of the Impact of the Sulphate Content on Nanoparticle Production and Cell Toxicity.

The composition of seaweeds is complex, with vitamins, phenolic compounds, minerals, and polysaccharides being some of the factions comprising their structure. The main polysaccharide in brown seaweeds is fucoidan, and several biological activities have been associated with its structure. Chitosan is another marine biopolymer that is very popular in the biomedical field, owing to its suitable features for formulating drug delivery systems and, particularly, particulate systems. In this work, the ability of fucoidan to produce nanoparticles was evaluated, testing different amounts of a polymer and using chitosan as a counterion. Nanoparticles of 200-300 nm were obtained when fucoidan prevailed in the formulation, which also resulted in negatively charged nanoparticles. Adjusting the pH of the reaction media to 4 did not affect the physicochemical characteristics of the nanoparticles. The IC50 of fucoidan was determined, in both HCT-116 and A549 cells, to be around 160 µg/mL, whereas it raised to 675-100 µg/mL when nanoparticles (fucoidan/chitosan = 2/1, w/w) were tested. These marine materials (fucoidan and chitosan) provided features suitable to formulate polymeric nanoparticles to use in biomedical applications.

The Effect of Fermentation Duration on Nutrition Composition of Seaweed (Sargassum sp.) Liquid Organic Fertilizer

This study aims to determine the effect of fermentation duration on the nutrient composition of seaweed liquid organic fertilizer (Sargassum sp). This research was conducted from May to June 2017 at The University of Muhammadiyah Parepare. Test materials used in the form of seaweed and lactobacillus. The container used in the implementation of this research is 6 bottles of 1000 ml size, before the bottles are used first the bottles are washed clean. Then each bottle is filled with extracts of Sargassum sp. as much as 800 ml and 40 ml of probiotics. Two bottles of treatment A (without fermentation), 2 bottles for treatment B (7 days fermentation), 2 bottles for treatment C (14 days fermentation). The design was a completely randomized design (CRD) with 3 types of each treatment. The results showed that micro nutrients that the iron (Fe) were obtained highest in treatment C (concentration 162 ppm), Silica (Si) in treatment A (100 ppm), manganese (Mn) in treatment B (29 ppm). For the highest macro nutrients potassium (K) obtained in treatment C (concentration 0.52%), Calcium (Ca) in treatment B (0.33%), Sulfur (S) in treatment C (0.31%) , Chlorine (Cl) in treatment C (concentration 0.27%). The research concludes that the length of time of fermentation affects the nutrient content of liquid organic fertilizer seaweed.

Biofuel Production from Seaweeds: A Comprehensive Review

Seaweeds represent a promising and sustainable feedstock for biofuel production which raises increasing research interests. Their high availability, easy fermentable composition, and good degradation potential make them a suitable candidate for alternating fossil fuels as an advantageous energy resource. This comprehensive review aims to summarize and discuss data from the literature on the biochemical composition of seaweeds and its potential for biomethane and biohydrogen production, as well as to investigate the effect of the common pretreatment methods. Satisfactory yields comparable to terrestrial biomass could be obtained through anaerobic digestion; concerning dark fermentation, the challenge remains to better define the operating conditions allowing a stable production of biohydrogen. Finally, we propose a potential energy production scheme with the seaweed found by the Caribbean Islands of Guadeloupe and Martinique, as well as current techno-economic challenges and future prospects. An annual energy potential of 66 GWh could be attained via a two-stage biohythane production process, this tends to be promising in terms of energetic valorization and coastal management.

Assessing the volatile composition of seaweed (Laminaria digitata) suspensions as function of thermal and mechanical treatments

Macroalgae are a rich source of dietary fibre, protein, lipids and bioactives. However, more research is needed to understand how processing methods impact macroalgae techno-functional properties. In this work, aqueous suspensions of the fibre-rich brown algae Laminaria digitata were prepared by conventional food processing methods. The impact of sequence of processing steps (thermal and mechanical treatments), and heating time (15, 30 and 45 min), on volatile aroma composition were investigated. Changes in volatile composition were monitored with headspace GC-FID/MS analysis. Our results showed that both parameters impacted the volatiles profile of the suspensions. From an overall volatile perspective, short heating times (90 °C for 15 min) led to similar profiles, independently of the sequence of thermal and mechanical treatments. However, longer heating times induced a larger release of several aldehydes, specific for each processing method. Our results bring new insights on the volatile composition of suspensions of Laminaria digitata, which are related to flavour properties, and aid design of food products containing seaweed.

Efficient utilization and management of seaweed biomass for biogas production

The global trend of seaweed production and their biomass utilization for biofuels generation is increased due to the high carbohydrate and protein content. Anaerobic digestion (AD) is a promising technology to convert organic compounds of seaweed biomass into biogas. However, a comprehensive review enclosing the biomethane potential, process parameters, microbial shifts, and effective approaches to enhance the digestibility and biogas production from seaweeds has not been reported. Thus, this article aims to explore, classify, and comprehensively present the potential of seaweeds for biogas production. The global trend of biofuels including biogas production from seaweed biomass is elucidated. The effect of seasonal variations on the biochemical composition of seaweeds is highlighted. The microbial community involved in AD of seaweeds is discussed. This article also covers the pretreatments, co-digestion, supplementation of additives, and sequential utilization of seaweeds to enhance biogas production. The seasonal variations significantly affected the composition of seaweeds and subsequently altered the content of inhibitory compounds. The application of different strategies (such as pretreatment) mitigated the effect of inhibitors and boosted biogas production. Firmicutes and Bacteroidetes were reported to be the major bacteria and Methanobacteriales were the dominant archaea during the digestion of seaweeds. Extensive research on microbial dynamics and the application of co-digestion is still needed to achieve complete utilization of biomass coupled with biogas enhancement.

Mineral content of macroalgae and possible uses for human health

Seaweeds have been used since ancient times as food, food additives, fertilizer, and a source of medicine. Like terrestrial plants, seaweeds contain many inorganic and organic substances which can beneficial to human health. Seaweeds have great potential as “bioactive compounds for functional use, “algae mineral supplements”, “pharmaceuticals and cosmetics” and in addition to their potential of good sources of minerals, trace elements, proteins, lipids, and carbohydrates as traditional food. Due to the mineral absorption ability of macroalgae from the seawater, many species are a perfect source of some trace elements such as iron and iodine and a good source of some macro minerals such as calcium, phosphate, and magnesium. In some cases, the mineral content of the seaweeds may be higher than that of land plants. Scientific data show that the bioavailability of algae minerals is higher than rock-based minerals for humans. In recent years, the potential use of seaweed minerals as “algae mineral supplements” gained attention due to their rich elemental composition and the importance of minerals for human health. Mineral composition of seaweeds may vary according to locality, season, residence time, species physiology, and environmental conditions such as level of elements in seawater, light intensity, and salinity. Thus, new approaches and researches are needed on how much seaweeds can be consumed daily and their potential health risks. In this study, the mineral contents of seaweeds, the importance of minerals for human health, and potential uses of algae minerals were investigated.

Studies on nutritional composition of three colour forms of Kappaphycus alvarezii (Doty) Doty

Biochemical composition of seaweeds is known to vary with species and environment. Kappaphycus alvarezii is an important commercial source of carrageenans (gel-forming and viscosifying polysaccharides). The nutritional and mineral composition of three (brown, green and pale yellow) colour forms of edible seaweed K. alvarezii is investigated in the current study. The brown colour form of this seaweed contained highest ash content of (25.99±0.22 %), crude fibre (21.0±0.68 %), and protein (8.92±0.41 %), while, the green form had highest carbohydrate (22.0±0.00 %) and sulphate (5.89±0.00 %) content. On the other hand, the pale yellow colour form had highest lipid content (0.72±0.00 %). Amongst the 17 minerals analyzed, highest total mineral macro-elements (viz. Na, K, Ca and Mg) were recorded in the brown form (18.8±0.71 g/100 g d wt) followed by the pale yellow (17.3±1.07 g/100 g d wt) and green colour form (11.9±1.22 g/100 g d wt). The micro-elements varied within the three colour forms; however, the brown colour form had maximum micro-element content (P, Cd, Pb, As, Hg, Cr, Zn, Cu, Fe, Mn, Co, Mo and Ni; 19.96±0.24mg/100 g d wt), followed by green (8.6±0.64 mg /100 g d wt) and pale yellow form (7.15±0.58mg /100 g d wt). On the basis of this study, it could be said that these three colour forms (i.e. brown, green and pale yellow) of Kappaphycus alvarezii could be utilized as a condiment in the omnivorous diet; however, a daily intake of 5.68 g d wt is recommended in case of the brown form, while in case of the green and pale yellow form a maximum daily intake of 9.55 and 10.5 g d wt, respectively is recommended. The study also reveals that the three colour-forms differed in their nutritional and mineral composition.

RP-HPLC-DAD determination of the differences in the polyphenol content of Fucus vesiculosus extracts with similar antioxidant activity

Significant quantities of bioactive compounds have been found in the chemical composition of seaweeds. This source of natural antioxidants such as polyphenols appears to attenuate lipid peroxidation caused by oxidative stress, preventing the harmful effects of a number of injuries including ischemia–reperfusion (I/R). Conventional extraction (CE) has been used for years as a traditional method for obtaining bioactive components from seaweeds. However, recent studies highlight ultrasonic-assisted extraction (UAE) as an alternative and more eco-friendly technique. Therefore, the two methods were optimised and compared to obtain a Fucus vesiculosus extract (FVE) with high antioxidant activity and polyphenol content. The highest antioxidant activity was obtained after 1 h at 25 °C for conventional extraction, and after 5 min at 35 °C for ultrasonic-assisted extraction. Higher concentrations of polyphenols were obtained with the optimal conditions in conventional extraction (13.61 mg PGE/g seaweed), but no significant differences were observed between the antioxidant activity obtained with UAE (89.33%) and CE (89.74%). The characterization of the polyphenols present in both optimised extracts was carried out and compared with reverse-phase high-performance liquid chromatography coupled to a diode array detector (HPLC-DAD). The following compounds were identified: phloroglucinol, gallic acid, catechin, vanillic acid, epicatechin, protocatechuic acid, rutin, gentisic acid, chlorogenic acid, caffeic acid, coumaric acid and ferulic acid. RP-HPLC-DAD results also showed higher concentrations of polyphenols in optimised extracts with CE. Consequently, CE was found to be more effective than UAE in providing extracts with higher concentrations of polyphenols, but UAE constitutes an efficient and more eco-friendly methodology for obtaining a FVE with the highest antioxidant activity.

Evaluation of Chemical, Functional, Spectral, and Thermal Characteristics of Sargassum wightii and Ulva rigida from Indian Coast

Usage of seaweeds as a functional food/food ingredient is very limited due to paucity of scientific information about variations in the nutritional composition of seaweeds under diverse climatic conditions. Sargassum wightii and Ulva rigida seaweeds are found abundantly on the Southern Indian coastline and were thoroughly evaluated in this work. Crude fiber and lipid of S. wightii were higher (24.93 ± 0.23% and 3.09 ± 0.41%, respectively) as compared to U. rigida; however, U. rigida had higher crude protein content (27.11 ± 0.62%). Evaluation of mineral and CHNS content indicated that the concentration of potassium, magnesium, and calcium was 1.36 ± 0.08 mg/g, 8.39 ± 0.80 mg/g, and 14.03 ± 3.46 mg/g, respectively, that was higher in the S. wightii, whereas U. rigida contained higher value of iron, carbon, and sulphur (0.70 ± 0.13 mg/g, 37.72 ± 4.63%, and 2.61 ± 0.16%, respectively). Swelling capacity (19.42 ± 0.00 mL/g DW to 22.66 ± 00 mL/g DW), water-holding capacity (6.15 ± 0.08 g/g DW to 6.38 ± 0.14 g/g DW), and oil-holding capacity (2.96 ± 0.13 g/g DW) of U. rigida were significantly ( p &lt; 0.05 ) higher as compared to S. wightii. It was observed from DSC thermograms that S. wightii can be safely processed for food formulations even at a temperature of 134°C. The thermograms also revealed changes in the sulphated polysaccharide (fucoidan) profile due to the presence of hydroxyl and carboxyl groups with denaturation of proteins. TGA of S. wightii and U. rigida showed degradation temperature within the range of 200–300°C due to divergent polysaccharide compositions. FTIR spectroscopy suggested the presence of phenolic groups in both seaweeds (at 1219 cm−1). Results of the study suggested that the manufacturing of functional food products from seaweeds could be beneficial and may aid in social upliftment of cultivators/fishermen.

Chemical Compositions of Brown and Green Seaweed, and Effects on Nutrient Digestibility in Broiler Chickens.

Simple SummaryThis study aimed to analyse the nutritional properties and apparent ileal digestibility of brown and green seaweed on broiler chickens. Proximate content, mineral and amino acid contents were analysed. In addition, the gross energy value of brown and green seaweed was measured. A digestibility trial was conducted to determine the apparent ileal digestibility of seaweed in broiler chickens. Apparent metabolisable energy was determined as well in this study. Birds were fed with 90.30% seaweed-based diet with an indigestible marker. At the end of the feeding trial, birds were euthanised and ileal digesta was collected. Nutrient contents of experimental feed and digesta were analysed, and gross energy was measured. The results revealed that there was no significant difference in the apparent ileal digestibility of dry matter, organic matter, crude lipid and ash contents among the brown and green seaweed-based diets. The findings also demonstrated that the apparent ileal digestibility of crude protein and crude fibre was significantly higher in brown seaweed compared to green seaweed. Nevertheless, no significant difference was observed in the apparent digestibility of metabolisable energy between the types of seaweed.This study aimed to analyse the nutritional properties, apparent ileal digestibility (AID) and apparent metabolisable energy (AME) of broiler chickens fed with brown seaweed (BS) and green seaweed (GS). Proximate analysis was performed to determine the nutrient composition of seaweed. The amino acids were determined using high-performance liquid chromatography (HPLC), and atomic absorption spectroscopy was used to determine the minerals content. The gross energy (GE) was determined using a fully automatic bomb calorimeter, and the AME value was calculated. Titanium dioxide (TiO2) was used as an indigestible marker to calculate the AID. A digestibility trial was conducted to investigate the effects of seaweeds on crude protein (CP), crude fibre (CF), ether extract (EE), dry matter (DM), organic matter (OM), amino acids (AA) and minerals digestibility, and AME on broiler chickens. Thirty-six broiler chickens were randomly distributed into two dietary treatment groups with six replicates and three birds per replicate. Results showed that brown and green seaweed was a source of macro and micronutrients. For the AME and AID of seaweed-based diets, the results showed that the AME value for BS and GS was 2894.13 and 2780.70 kcal/kg, respectively. The AID of BS and GS was 88.82% and 86.8% for EE, 82.03% and 80.6% for OM, 60.69% and 57.80% for CP, 48.56 and 44.02% for CF, and 17.97 and 19.40% for ash contents, respectively. Meanwhile, the AID of CP and CF was significantly higher for BS compared to the GS. Findings showed that the AID of various AA was 40.96 to 77.54%, and the AID of selected minerals (Ca, Na, K, Mg, Zn, Cu, Fe) for both BS and GS groups were above 90%.