Seaweed Samples Research Articles

Algicoccus marinus gen. nov. sp. nov., a marine bacterium isolated from the surface of brown seaweed Laminaria japonica.

A Gram-staining-negative, strictly aerobic, non-motile, ovoid- to rod-shaped bacterium, designated as HZ20T, was isolated from the surface of a brown seaweed (Laminaria japonica) sample collected from the East China Sea. Colonies are 1.0-2.0mm in diameter, smooth, circular, convex and yellow after grown on MA at 28°C for 72h. The strain was found to grow at 4-50°C (optimum, 37°C), pH 5.0-9.5 (optimum, pH 7.0-7.5) and with 0-10% (w/v) NaCl (optimum, 1.0-1.5%). Chemotaxonomic analysis showed ubiquinone-8 as the only quinone, C17:0 cyclo, C16:0, summed feature 8 (C18:1ω7c and/or C18:1ω6c) and summed feature 2 (C12:0 aldehyde/unknown 10.9525/C16:1 iso I/C14:0 3OH) as the major fatty acids (> 5%), and diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, one unidentified amino phospholipid, two unidentified phospholipids, five unidentified glycolipid and two unidentified lipids as the polar lipids. The DNA G + C content was 55.5mol%. 16S rRNA gene sequences of the isolate showed highest similarities to Bordetella flabilis AU10664T (97.1%), Parapusillimonas granuli Ch07T (97.1%), Paracandidimonas soli IMT-305T (97.1%), Kerstersia gyiorum LMG5906T (97.0%) and Bordetella sputigena LMG 28641T (97.0%). The phylogenetic trees using 16S rRNA gene and genome sequences both showed that the strain HZ20T formed a deep branch separated from other related genera, indicating that it represents a novel species of a novel genus. The calculated average nucleotide identity (ANI) and percent of conserved proteins (POCP) values using genome sequences of strain HZ20T and related strains also support this conclusion. Based on the phenotypic properties and phylogenetic distinctiveness, we propose strain HZ20T (= MCCC 1K03465T = KCTC 62330T) to represent a novel species of a novel genus with the name Algicoccus marinus gen. nov. sp. nov.

Antibacterial Activity From Seaweeds Turbinaria ornata and Chaetomorpha antennina Against Fouling Bacteria

Biofouling is a serious problem for marine industries, it can damage many constructions which are submerged in the water and the bacteria are the inisiator of that problem. Commercial antifouling agents which have been using widely is not that effective regarding to the after-effect in the ecosystem. Thus, investigating on natural products which can against fouling bacteria is really essential. This research reported the potentials of seaweeds Turbinaria ornata and Chaetomorpha antennina against fouling bacteria which have been tested on the inhibition zone and phytochemical contents. The seaweed samples were extracted using various solvents such as hexane, ethyl acetate and methanol. The results showed that C. antennina had more potentials against the fouling bacteria than T. ornata regarding to the maximum inhibition zone. C. antennina extract had 6 mm at 10 μl/disk when T. ornata only had 2 mm at 10 μl/disk. In addition, C. anteninna extracts also had more phytochemical contents (phenol, flavonoid, steroid, saponin, alkaloid and triterpenoid) than T. ornata extracts (phenol, steroid, saponin, and alkaloid). Having larger maximum inhibition zone and more phytochemical contents indicated that C. anteninna can be the natural source candidate for antibacterial agent especially fouling bacteria.

Metabolome profiling of various seaweed species discriminates between brown, red, and green algae.

Among seaweed groups, brown algae had characteristically high concentrations of mannitol, and green algae were characterised by fructose. In red algae, metabolite profiles of individual species should be evaluated. Seaweeds are metabolically different from terrestrial plants. However, general metabolite profiles of the three major seaweed groups, the brown, red, and green algae, and the effect of various extraction methods on metabolite profiling results have not been comprehensively explored. In this study, we evaluated the water-soluble metabolites in four brown, five red, and two green algae species collected from two sites in northern Japan, located in the Sea of Japan and the Pacific Ocean. Freeze-dried seaweed samples were processed by methanol-water extraction with or without chloroform and analysed by capillary electrophoresis- and liquid chromatography-mass spectrometry for metabolite characterisation. The metabolite concentration profiles showed distinctive characteristic depends on species and taxonomic groups, whereas the extraction methods did not have a significant effect. Taxonomic differences between the various seaweed metabolite profiles were well defined using only sugar metabolites but no other major compound types. Mannitol was the main sugar metabolites in brown algae, whereas fructose, sucrose, and glucose were found at high concentrations in green algae. In red algae, individual species had some characteristic metabolites, such as sorbitol in Pyropia pseudolinearis and panose in Dasya sessilis. The metabolite profiles generated in this study will be a resource and provide guidance for nutraceutical research studies because the information about metabolites in seaweeds is still very limited compared to that of terrestrial plants.

Application of chemometric techniques: An innovative approach to discriminate two seaweed cultivars by physico-functional properties

Chemometric techniques were employed to discriminate two Indonesian seaweed cultivars (Kappaphycus alvarezii and Sargassum duplicatum) based on their physico-functional properties. Data of physico-functional properties, including emulsifying activity and bulk density, were processed using multivariate, discriminant analysis (DA), principal component analysis (PCA), and cluster analysis (CA). Significant differences (p < 0.05) and discrimination (multivariate analysis (F9,14 = 57.85; Wilks’s lambda = 0.02, p < 0.0001)) were determined among physico-functional properties of seaweed powders. In addition, DA method clarified (Λ = 0.02 and χ2 = 63.74) variations between samples along with two discriminate functions. Moreover, PCA (49.63% with Eigenvalues > 1) and CA (clusters 1 and 2) methods confirmed that the seaweed samples possessed differing physico-functional properties, which implied their distinctive use in food product development. Overall, our results demonstrated strong variation in seaweed powers using chemometrics, which might contribute to the rapid applicability of chemometrics in evaluating novel food material.

Seaweeds as source of the essential elements

Overtime seaweeds have been used as a food mainly due to their high nutritional value. This type of food is considered as functional food and contributes to the nutritional human requirements, being beneficial to human health. In this study 13 edible seaweed samples acquired in the marked of São Paulo city were analyzed and the concentrations of elements Cl, K, Mg, Mn and Na were determined by Instrumental Neutron Activation Analysis (INAA). The following edible seaweeds were analyzed: Nori (Porphyra umbilicates); Hijiki (Hijikia fusiforme); Kombu (Laminaria sp.) and Wakame (Undaria pinnatifida) species from China, USA, Japan and South Korea. The Undaria pinnatifida species presented the highest Na concentration and the lowest K level. The highest variation was obtained for Mn in the Porphyra umbilicates species.

Metals accumulation in edible marine algae collected from Thondi coast of Palk Bay, Southeastern India

This study aimed to monitor the concentrations of metals including Cd, Pb, Cu and Zn in commercially important and commonly edible brown, red and green algal species collected from Thondi coast, southeast India. Green seaweed Chaetomorpha linum contained higher (Cd 8.51 mg kg−1, Pb 5.24 mg kg−1, Cu 15.38 mg kg−1, and Zn 22.34 mg kg−1) concentrations of metals than other tested seaweed samples. The concentrations of metals significantly varied within and between the investigated species of seaweed samples (P < 0.05). It was revealed that Cd, Pb, Cu and Zn metals were present in the species of seaweeds at different concentration. The residual levels of metals were less than the maximum allowable levels specified for human consumption compared to PTWIs, JECFA, FAO/WHO, FSSAI and EC. This study suggested that exposure to the analysed metals (Cd, Pb, Cu and Zn) through seaweeds consumption does not raise serious health effects to consumers and it is safe for human consumption.

JENIS-JENIS MAKROALGA EPIFIT PADA BUDIDAYA (Kappaphycus alvarezii) DI PERAIRAN TELUK GERUPUK LOMBOK TENGAH

Abstract:Epiphytes are organisms that attach to other organisms to support their growth and development. One type of epiphytes that has a negative impact on the host is algae (macroalgae). This algae is a competing organism for cultivation algae (Kappaphycus alvarezii). This research was conducted From May to October 2017 in Gerupuk Bay, Central Lombok. The aim of the research is to find out the types of macroalgae epiphytes on macroalgae kappaphycus alvarezii. This research was conducted using exploratory methods by taking seaweed samples overgrown with epiphytes, the research data obtained were descriptive analisys. As supporting data, environmental parameters are measured including temperature, pH, salinity, DO, phosphate, and NH4. Based on the results of exploration found 13 species of epiphytic algae in kappaphycus alvarezi cultivation, namely: Chaetomorpha linum, Chaetomorpha linum, Cladophora dalmatica, Acanthophora spicifer, Batrachospermum sp, Callithamnion sp., Caulachantus ustulatus, Ceramium sp, Hypnea spinnosa, Hypnea spinella, Hypnea sp, Polysiphonia brodiaei , Spyridia filamentosa. The type of epiphytes found that grows in both cultivation methods and some others are found only in one method. Meanwhile, data on environmental parameters are in the optimal range for macroalgae growth.This data is expected to be used as a consideration for the cultivateddevelopment in the Gerupuk Bay cultivation center. Keywords : Macroalgae, Epiphytes, Aquaculture, Kappaphycus alvarezii

Toxic metals (Al, Cd, Pb and Hg) in the most consumed edible seaweeds in Europe

Algae are becoming increasingly common because of their importance in vegan and vegetarian diets. Although they are a source of essential minerals, vitamins and antioxidants, these marine organisms have a high absorption capacity that can lead to the accumulation of toxic metals which are dangerous in humans. The objective of this study is to determine the content of toxic metals (Al, Cd, Pb and Hg) in edible seaweed samples marketed in Spain (Europe) to assess the toxicological risk from the intake of these metals. A total of 73 European and Asian algae samples marketed in Tenerife (Canary Islands, Spain) were analyzed by ICP - OES (Inductively Coupled Plasma – Optical Emission Spectrometry) and by CV-AAS (Cold Vapor – Atomic Absorption Spectrophotometry). The major toxic metal was Al, whose highest level was recorded in seaweed salad (57.5 mg Al/kg dry weight). Regarding the origin, the highest concentrations of Al (38.9 mg/kg dw), Cd (0.59 mg/kg dw) and Pb (0.40 mg/kg dw) were found in Asian algae, which may be due to the high levels of industry in the Asian countries. However, the highest concentration of Hg (0.017 mg/kg dw) was found in European algae. The consumption of 5 g of dehydrated seaweed per day represents a percentage of contribution to the tolerable weekly intake of Cd of 22.7%, this percentage may entail a risk when considering total Cd intake. However, the consumption of 5 g a day of dehydrated seaweed would not, pose a risk to the health of adults.

Validation and inter-laboratory study of selective hydride generation for fast screening of inorganic arsenic in seafood

It is advisable to monitor and regulate inorganic arsenic (iAs) in food and feedstuff. This work describes an update and validation of a method of selective hydride generation (HG) with inductively coupled plasma mass spectrometry (ICP-MS) for high-throughput screening of iAs content in seafood samples after microwave-assisted extraction with diluted nitric acid and hydrogen peroxide. High concentration of HCl (8 M) for HG along with hydrogen peroxide in samples of a same concentration as used for extraction leads to a selective conversion of iAs to volatile arsine that is released and transported to the detector. A minor contribution from methylarsonate (≈20% to iAs) was found, while HG from dimethylarsinate, trimethylarsine oxide is substantially suppressed (less than 1% to iAs). Methodology was applied to Certified Reference Materials (CRMs) TORT-3, DORM-3, DORM-4, DOLT-4, DOLT-5, PRON-1, SQID-1 and ERM-CE278k, in some of them iAs has been determined for the first time, and to various seaweed samples from a local store. The results were always compared with a reference method and selectivity of iAs determination was evaluated. An inter-laboratory reproducibility was tested by comparative analyses of six fish and four seaweed samples in three European laboratories, with good agreement of the results. The method of HG-ICP-MS is sensitive (limit of detection 2 μg kg−1 iAs), well suited for screening of large number of samples and selective at iAs concentration levels at which maximum limits are expected to be set into EU legislation for marine samples.

Marine radioactivity of Cs-134 and Cs-137 in the Malaysian Economic Exclusive Zone after the Fukushima accident

Seawater, sediment, biota and seaweed samples were collected in the Malaysian Economic Exclusive Zone (EEZ) marine environment within April 2012 to April 2014 as part of the marine radioactivity monitoring activities following the Fukushima Daiichi Nuclear Power (FDNPP) accident. The objectives of this study were to quantify radioactivity releases of Cs-134 and Cs-137 from the FDNPP into the Malaysian EEZ marine environment and to evaluate its potential impact on radionuclide levels in the marine life. The results showed Cs-134 in seawater, sediment and; biota and seaweeds were ranged from 1.3 to 2.2 Bq m−3, 1 to 1.9 Bq kg−1 dw. and < 0.01 to 0.2 Bq kg−1 fw., respectively. The levels of Cs-137 and Cs-134 as a radioisotopic signature for FDNPP discharges indicated that no new inputs into Malaysian marine environment, thus definitely confirmed the radioactive water released from FDNPP accident does not contaminate our marine environment. The estimated total dose and risk quotient using ERICA Assessment Tool showed the Cs-137 activity concentration in Malaysian marine environment was far below the screening value and does not cause any risk to the living organism. Thus, all our seafood including seaweeds are safe for human consumption.

Carotenoid and Chlorophyll Profiles in Five Species of Malaysian Seaweed as Potential Halal Active Pharmaceutical Ingredient (API)

Seaweed, also known as macroalgae, consist of various species that have been gaining the interest of researchers due to the presence of functional bioactive compounds that can be extracted from their biomass. This research aimed to study the chlorophyll and carotenoid content from five species of Malaysian seaweed as potential Active Pharmaceutical Ingredient (API). Three species of red macroalgae, (Eucheuma denticulatum, Gracilaria tikvahiae, and Kappaphycus striatum), green macroalgae (Caulerpa lentillifera ) and one brown macroalga (Padina pavonica) were selected and their chlorophyll and carotenoid contents were determined by using UV-Vis spectrophotometer and HPLC. Their antioxidant and antimicrobial activities were investigated using DPPH Radical Scavenging activity and Disc Diffusion methods, respectively. In terms of carotenoid content, P. pavonica contained the highest amount of carotenoid (100.9 ± 14.7 ug/g DW) and chlorophyll content (7.5 ±1.5 ug/g DW). Meanwhile, based on individual carotenoid content, K. striatum had the highest lutein content (38.6 ug/g DW). Zeaxanthin, beta-carotene, and violaxanthin were significantly higher in C. lentillifera at 21.3 ug/g DW, 10.7 ug/g DW, and 8.9 ug/g DW respectively. Besides that, the antioxidant test showed that P. pavonica presented the strongest DPPH activity with the percentage of inhibition (I %) of (61.0 % ± 0.9). Finally, for the antimicrobial test, strong antimicrobial activities were shown by all the seaweed samples toward E. coli and P. aerugenosa. Overall results of the antifungal test demonstrated moderate antifungal action by all seaweed samples towards M. gypseum and Fusarium sp.

Selective and fast screening method for inorganic arsenic in seaweed using hydride generation inductively coupled plasma mass spectrometry (HG-ICPMS)

A method for the determination of inorganic arsenic (iAs) without chromatography using hydride generation — inductively coupled plasma mass spectrometry (HG-ICPMS) is applied to 40 brown macroalgae samples (Fucus vesiculosus, Ascophyllum nodosum, Saccharina latissima). Determining iAs in seaweed matrices is a challenge and, in this study, using 2% HNO3 and 3% H2O2 extraction media the HG-ICPMS outperformed the most commonly used method of HPLC-ICPMS for the determination of iAs in the seaweed samples. There was a good comparison between the simple and fast HG-ICPMS and the more accurate but time-consuming HPLC-HG-ICPMS. Linear regression showed reasonable linearity (R2 of 0.82), with a slope slightly higher than 1 (1.15 ± 0.09) and intercept 0.03 ± 0.01 when comparing the concentrations of iAs determined with the two methods. Hence there is a minor overestimation of iAs with HG compared to the HPLC-HG, however, the method is well suited as a quick screening method. The iAs concentration was below 1% of total arsenic concentration for all the seaweed samples irrespective of using HG-ICPMS or HPLC-HG-ICPMS.

Seasonal and depth variations in the chemical composition of cultivated Saccharina latissima

Sugar kelp (Saccharina latissima) is an abundantly available macroalgae species along the Norwegian coast, and there is currently emerging an industry based on seaweed cultivation. In this study, the biomass growth of cultivated S. latissima deployed in February was studied at cultivation depths of 3 and 8 meters (m) and monitored over the period of May, June, and August. The highest biomass production was observed in June at the depth of 3 m (38.3 kg wet weight m−2). Furthermore, all seaweed samples underwent a detailed chemical characterization including analysis of carbohydrates (glucose, mannitol, fucose, xylose, uronic acids), amino acids and minerals. The macroalgae deployed in February at 3 m depth and sampled in June had the highest proportion of total sugars (534.5 g kg−1 of DM) and the lowest content of ash (252.7 g kg−1 of DM). Thus, cultivation at 3 m and harvesting in June are suitable when the feedstock is used for biochemical production of fuels and chemicals. Macroalgae deployed at 8 m depth and harvested in August had the highest proportion of total amino acids (242.4 g kg−1 DM) and ash content (411.5 g kg−1 DM). This biomass may be suitable as a nitrogen and mineral source in microbial growth media. Overall, the choice of cultivation depth and harvesting time depends on the intended use of the seaweed biomass.

RESEARCH OF CHEMICAL COMPONENTS OF SOME SEAWEED SPECIES IN CON CO ISLAND – QUANG TRI PROVINCE

11 samples of 8 seaweed families were collected at Con Co – Quang Tri and determined ofthe chemical compositions. The analysis results showed that these seaweed samples in Con Cocontain high content of trace elements and low content of heavy metals. Many samples havegood lipid quality to meet the requirements of safe food, as well as being good for the humanhealth (such as CC1, N9, N4, and N6 samples). Especially, some seaweed samples were foundto contain long-chain fatty acids with many double bonds presenting high bioactivity in theirlipid composition, such as C20: 4n-6 (AA) up to 22.35% (Hypnea flagelliformis Grev., sampleN6), C20: 5n-3 (EPA) 16.36 % (Grateloupia lithophila, sample N9), C22: 6n-3 (DHA) 1.07 %(Hypnea esperi, sample N2), C22: 5n-3 (DPA) 1.82% (Liagora spl., samples N4).

Polycyclic aromatic hydrocarbons bioaccessibility in seafood: Culinary practices effects on dietary exposure

This work aimed to determine the effect of culinary practices on the contamination level and bioaccessibility of polycyclic aromatic hydrocarbons (PAHs) in seafood. The selected farmed seafood species (marine shrimp, clams and seaweed) were commercially available in Portugal. The mean concentrations of PAHs varied between 0.23 and 51.8 µg kg−1, with the lowest value being observed in raw shrimp and the highest in dried seaweed. The number of compounds detected in seaweed and clams (naphthalene, acenaphthene, fluorene, phenanthrene, benzo(b)fluoranthene and benzo(j)fluoranthene) were higher than in shrimp (fluorene and pyrene). Among the PAHs measured, fluorene was the predominant one. There was a significant interaction effect between species and culinary treatment (p < 0.05), thus boiled and dried seaweed samples presented the lowest and the highest levels of fluorene (0.13 and 1.8 µg kg−1), respectively. The daily intake of PAHs decreased with bioaccessibility, varying from 22% for benzo(k)fluoranthene (in raw clam) to 84% for phenanthrene (in steamed clam). According to the potency equivalent concentrations, screening values and bioaccessibility of PAHs, the consumption of marine shrimp, clam and seaweed is considered as safe for consumers.

Applicability of an in vitro gastrointestinal digestion method to evaluation of toxic elements bioaccessibility from algae for human consumption

ABSTRACTThis study aimed to investigate the bioaccessibility of toxic elements, including aluminum (Al), arsenic (As), nickel (Ni), cadmium (Cd), and lead (Pb) in five commercial algae consumed by humans in Italy. The degree of bioaccessibility of these elements may have important implications for human health. Simulation of gastrointestinal tract (GIT) digestion was divided into three stages through use of synthetic saliva, gastric, and bile–pancreas solutions. After pre-treatment with a saliva solution, seaweed samples underwent one of the following treatments: (1) simulated gastric digestion only or (2) simulated complete GIT digestion (gastric digestion followed by bile-pancreas digestion). The bioaccessibility of these toxic elements ranged from approximately 5% to 73% and from 4% to 77% in gastric and GIT digestion, respectively. The bioaccessibility of Al and Pb is poor (5–15%), As and Ni were fairly (40–55%), while Cd displayed a high bioaccessibility. No significant differences in toxic elements mobility was found between samples that only underwent gastric digestion compared to those that underwent a complete GIT digestion.

Bioaccessibility of heavy metals in the seaweed Caulerpa racemosa var. corynephora: Human health risk from consumption

ABSTRACTThis study reports the total and bioaccessible concentrations of heavy metals (Mn, Fe, Cu, Zn, Cd and Pb) in the seaweed Caulerpa racemosa var. corynephora collected from local markets along the Andaman coast of Krabi Province, Thailand. Microwave-assisted acid digestion (EPA Method 3052) was used for sample preparation prior to total metal analysis. The in vitro Unified Bioaccessibility Method (UBM) was applied to assess the bioaccessibility of the metals in the seaweed samples. The total, gastric phase, and residual fraction concentration were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES). The total amounts found in the seaweed samples, in ascending order were Cd < Pb < Cu < Zn < Mn < Fe with the mean concentrations of 0.89, 0.97, 17.4, 59.0, 63.4, and 450 mg/kg dry weight, respectively. High bioaccessibility percentages for Mn (71.8–85.3%) were observed alongside moderate bioaccessibility percentages for Cu (44.3–56.3%), Zn (37.7–47.4%), and Cd (41.8–46.7%), a low bioaccessibility percentage for Pb (22.3–32.0%), and a very low bioaccessibility percentage for Fe (11.5–16.5%). A quality control procedure was implemented which involved the analysis of a certified reference material (Seaweed NMIJ CRM 7405-a) for total metals and a mass-balance approach for the assessment of the in vitro bioaccessibility method.

Evaluation of abundance of artificial radionuclides in food products in South Korea and sources

Food samples are collected nationwide from January 2016 to February 2017 and their contents of artificial radionuclides are measured to address the growing concerns regarding the radioactive contamination of food products in Korea. Specifically, 900 food samples are collected for this study and their contents of representative artificial radionuclides 134Cs, 137Cs, 239,240Pu, and 90Sr are analyzed. The analysis shows that the activity concentrations of 137Cs in fish range from minimum detectable activity (MDA) to 340 mBq/kg of fresh weight. The concentration factor (CF) determined for 137Cs as a measure of its bioavailability is calculated to be ca. 74 and found to be very similar to that (100) recommended by the International Atomic Energy Agency. With an MDA of <0.221 mBq/kg, the results reveal that 239,240Pu values in fish are below the MDA. The activity concentrations of 137Cs and 90Sr are lower than the MDA in both shellfish and seaweed, while the activity concentrations of 239,240Pu in shellfish range from 0.26 to 2.18 mBq/kg, and for seaweed samples range from 2.07 to 3.38 mBq/kg. The atom ratios of 240Pu/239Pu in shellfish caught at the Korean coast vary from 0.209 to 0.237, with a mean of 0.227. The higher 240Pu/239Pu atom ratio determined in shellfish is thought to be caused by the plutonium transported from the Pacific Proving Grounds rather than other sources such as the Fukushima nuclear power plant accident. The activity concentrations of 137Cs in mushrooms are found to vary from 1.0 to 21.4 Bq/kg, with the highest concentrations observed in the Oak (shiitake) and Sarcodon asparatus. 134Cs is detected in three mushroom specimens collected from Jeju Island and about 3–3.6% of 137Cs present in the wild mushrooms native to the Jeju Island are introduced as a result of the Fukushima nuclear plant accident. The annual effective doses of 137Cs received through consumption of mushrooms and fish are 2.0 × 10−4 mSv yr−1 and 3.9 × 10−5 mSv yr−1, and those values are negligible compared to the annual effective doses limit of 1 mSv yr−1.

Arsenic speciation analysis in seaweed and rice flour samples by ion chromatography combined with inductively coupled plasma-mass spectrometry

Arsenic speciation analysis in seaweed and rice flour samples by ion chromatography combined with inductively coupled plasma-mass spectrometry

Quantification of labile and stable non-polar arsenolipids in commercial fish meals and edible seaweed samples

The importance of sample preparation for arsenolipid speciation is highlighted as the order of sequential extraction revealed labile non-polar arsenolipids likely due to species transformation.