Source Of Carrageenan Research Articles

Metabolite expression changes in Kappaphycus alvarezii (a red alga) under hypo- and hyper-saline conditions

Kappaphycus alvarezii is an important red seaweed cultivated as a source of carrageenan and crop growth stimulant. The recurrent salinity fluctuations related to weather variability significantly influence the K. alvarezii cultivation. We report on the evaluation of metabolite changes in K. alvarezii under hypo- (16 ppt), control (32 ppt) and hyper- (48 ppt) saline conditions to unveil the metabolic responses of K. alvarezii under fluctuating salinity. The present study identified a total of 66 different metabolites under studied salinity strengths. The hypo-salinity up-regulated aspartate (0.77 folds) and tyrosine (0.71 folds) and down-regulated phenylalanine (0.51 folds) and proline (0.05 folds). Hyper-salinity up-regulated aspartate (0.64 folds), proline (0.55 folds), serine (0.84 folds) and tyrosine (0.97 folds) in K. alvarezii. Variable importance in the projection (VIP) score plot analysis observed these biomolecules as important metabolites in K. alvarezii under variable saline conditions. Most of the sugars got down-regulated under both saline conditions except mannose which exhibited 0.84 folds up-regulation under hyper-saline condition. K. alvarezii exhibited up-regulation of unsaturated fatty acids under hyper-saline conditions as compared to hypo-saline conditions. These results indicated differential metabolomic responses in K. alvarezii and different mechanisms of salinity acclimatization under control, hypo- and hyper-saline conditions.

A Study of Asparagus Preservation Capacity of Chitosan-Alginate and Chitosan-Carrageenan Biofilms

Fresh postharvest green asparagus rapidly deteriorate due to its senescence process and high transpiration rate. This thesis aims to utilize the available sources of carrageenan and alginate for combining with pure chitosan coating solution, thus create a new multi-component coating that can overcome the limitations of pure chitosan coating, and show more effective in maintaining the quality of postharvest green asparagus. The gel solution ratio 2:1 (v/v) of chitosan 1% (w/v) and alginate 0.2% (w/v), had ability to prolong shelf-life of asparagus for 3 days (from weight loss point of view) and 7 days (from visual quality point of view) compared to control sample. The weight loss was less than about 12% and also ensured lower firmness change, maintained higher chlorophyll content, exhibiting better quality of asparagus compared to control and chitosan coated sample. The chitosan-alginate (2:1 v/v) coated asparagus achieved highest sensory score in day 7 and 14 of storage and lowest total aerobic growth in 14 days of storage at 4 ºC. The coating biofilm of chitosan-alginate could be considered as the new multi-component edible coating which showed high effectiveness in quality preservation and shelf-life extension of asparagus.

Ecotypes of Hypnea pseudomusciformis (Cystocloniaceae, Rhodophyta) revealed by physiological, morphological, and molecular data

The red seaweed Hypnea pseudomusciformis has economic potential for mariculture as a source of carrageenan and other products. This work investigates this species along the Brazilian coastline by evaluating the effects of irradiance (40, 70, and 100 μmol photons m−2 s−1) on the number of differentiated branches (Br), growth rates (GR), photosynthesis parameters, and pigment content of tetrasporophytes from five distinct geographical populations extending from 5° to 27° S of latitude. The specimens showed intraspecific divergence for COI-5P marker, divided into three haplotypes with distinct geographical distribution. Although irradiance effects were significant only for GR and Br, intraspecific diversity was significant in all variables analyzed, with the haplotype of the tropical zone (5° to 12° S) displaying higher GR, Br, and maximum quantum yield (Fv/Fm) than the haplotype of the subtropical zone (23° to 27° S), which displayed higher pigment concentration. The geographic intermediate haplotype (19° S) displayed similar GR, Br, and Fv/Fm to the tropical haplotype, but similar pigment content to the subtropical haplotype. Our results indicate the presence of ecotypes within H. pseudomusciformis throughout its geographic distribution. Considering the set of physiological attributes, specimens from the tropical zone have higher potential for mariculture.

Structure and anticancer activity of a new lectin from the cultivated red alga, Kappaphycus striatus.

The red alga Kappaphycus striatus is economically important food species and extensively cultivated throughout most tropical parts of the world as a source of carrageenan. In this note, the primary structure of a new lectin KSL from this alga was elucidated by the rapid amplification method of complementary DNA (cDNA) ends, which consists of 267 amino acid residues distributed in four tandem-repeated domains of about 67 amino acids and sharing 43% of identity. The calculated molecular mass from the deduced sequence was consistent with that of natural KSL (27,826 Da) determined by electron spray ionization–mass spectrometry. The primary structure of KSL showed high similarity to those of the high mannose N-glycan specific lectins from marine red algae, ESA-2 from Eucheuma serra, EDA-2 from Eucheuma denticulatum, KSA-2 from Kappaphycus striatum, KAAs from Kappaphycus alvarezii and SfLs from Solieria filiformis, and from microorganisms, BOA from Burkholderia oklahomensis, MBHA from Myxococcus xanthus, OAA from Oscillatoria agardhii and PFL from Pseudomonas fluorescens. Furthermore, KSL showed anticancer effects against five carcinoma cell lines, HT29, Hela, MCF-7, SK-LU-1 and AGS, in a dose-dependent manner with the IC50 values of 0.80–1.94 µM, whereas its inhibition activities on cancer cells were not detected in the presence of yeast mannan, an inhibitor against lectin KSL. The cultivated red alga K. striatus could also be a good source of functional lectin(s) for application as anticancer agents.Graphic abstract

Physicochemical properties of carrageenan originated from Lermatang Village, Southwest Maluku District

Lermatang Village is situated at Southwest Maluku Regency and is known as a producer of seaweed. Generally, the seaweed produced in this village belongs to Eucheuma cottonii, which is a source of carrageenan and has high economic value. Carrageenan is known as raw material for the pharmaceutical, cosmetic, food and other industries, as gelling agents, material binders, emulsifiers, and stabilizers. The most common problem faced by the seaweed grower was they haven’t been able in optimizing the processing technologies yet. The seaweed farmer is still selling the seaweeds in form of dry seaweed without further processing and this cause a low price. The aim of this research was to study the physicochemical properties of carrageenan of Eucheuma cottonii originated from Lermatang Village fo Southwest Maluku Regency. Seaweed was extracted by using sodium hydroxide then physicochemical properties of carrageenan were observed. The results showed that physicochemical properties of carrageenan were indicated by yield 34.50 – 44.25 g, gel strength 500 - 850 g/cm2, viscosity 35.2- 40.89 cP, water content 14.32-25.73%, ash content 21.34-22.62% and sulphate content 14.85-16.50%.

Secondary attachment discs: a new alternative for restoring populations of Chondracanthus chamissoi (Gigartinales, Rhodophyta)

When facing the growing, international demand for the species Chondracanthus chamissoi as a source of carrageenan and for human food consumption, it is very important to generate new aquaculture techniques that allow for its repopulation, maximizing biomass yield whilst reducing the pressures on existing small, natural populations. This paper describes the use of secondary attachment discs (SAD) as a new vegetative propagation technique. It involves the following two stages: i) Tying the tetrasporophytic and cystocarpic fronds to natural substrates (shells and rocks), the conditions generated in the tanks allowed for quick SAD formation (12 days of experimentation), and ii) The maintenance of SAD under normal conditions (at sea for 83 days). The results indicated a quick formation of SAD, a high capacity of persistence (40%), the growth of new apices (4% d -1 ), quick substrate colonization through colonization discs (SADc), and the formation of reproductive structures. As a result, SAD is therefore proposed as both an innovative way to achieve the recovery of the now reduced natural beds of C. chamissoi and as an alternative to traditional methods of vegetative culturing for a species of high commercial interest.

Extraction Procedure and Partial Characterization of Polysaccharide from <i>Eucheuma gelatinae</i>

Eucheuma is a species of red alga and one of the primary sources of carrageenan. It utilizes floridean polysaccharides as food reserves. Industry has more concerns on Eucheuma is its carrageenans, however, most of other materials in Eucheuma has gone down the drain. Eucheuma gelatinae contains a certain amount of polysaccharides, which has various biological activities. In this study, alkaline extraction of acidic polysaccharide from Eucheuma gelatinae was applied.The polysaccharide structure and monosaccharide composition were also investigated by IR and GC.

Developmental pattern of crust into upright thalli of Grateloupia asiatica (Halymeniaceae, Rhodophyta)

Grateloupia asiatica is an edible seaweed and source of carrageenan in Korea. Considering the economic importance of this edible seaweed, mass culturing methods from spores have been conducted. Moreover, it helps prevent natural population depletion. Spores germinate to form crusts, filaments and spherical structures that subsequently differentiate and develop into thalli. The objective of our research was to study the developmental pattern of crust into upright thalli. Vegetative cells of crust divided circularly to expand and coalescence with other crusts, while those cells that divide vertically increase the thickness of the crust. The specific growth rate of the crusts was optimal at 20 °C (8.6 % day−1) and 42 μmol photons m−2 s−1 (10.8 % day−1). At optimum condition, they grew in regularity that forming pattern of zonation and circular mounds onto the crusts subsequently produce upright thalli. Thalli would be generated if the crusts, generally composed of six cells in thickness, will start to produce cortical and medulla cells to support and generate upright thalli. In the tank culture, the upright thalli grew rapidly during July to October and reached a maximum length of around ±5.2 cm. The thalli matured and contained many carposporangia in the branches after 150 culture days.

Ploidy determination of three Kappaphycus alvarezii strains (Rhodophyta, Gigartinales) by confocal fluorescence microscopy

Kappaphycus alvarezii is a red alga that is commercially important as a source of carrageenan. Since K. alvarezii presents large phenotypic plasticity and rarely develops reproductive structures in culture, identification of gametophytic and tetrasporophytic phases in cultivation systems are difficult. The aim of this study was to determine the ploidy of three K. alvarezii strains previously identified as brown “tetrasporophyte”, brown “gametophyte” and “Edison de Paula” (EP). Nuclei from these strains were stained with DAPI, and analyzed using confocal fluorescence microscopy and ImageJ software. The brown “tetrasporophyte” had the highest nuclear fluorescence intensity, consistent with a diploid tetrasporophyte (2N). The brown “gametophyte” and “EP” strains had nuclear fluorescence intensities of 55.78% and 57.10% in relation to the tetrasporophyte, respectively, consistent with haploid gametophytes (N). The present study demonstrated that this technique can be used as a rapid and effective tool to distinguish between haploid (gametophytic) and diploid (tetrasporophytic) plants of K. alvarezii, in addition to help identify new strains developed through alterations of ploidy level.

High-mannose N-glycan-specific lectin from the red alga Kappaphycus striatum (Carrageenophyte)

From a fresh sample (1 kg) of cultivated red alga Kappaphycus striatum, three isolectins, KSA-1 (15.1 mg), KSA-2 (58.0 mg) and KSA-3 (6.9 mg), were isolated by a combination of extraction with aqueous ethanol, ethanol precipitation, and ion exchange chromatography. Isolated KSAs were monomeric proteins of about 28 kDa having identical 20 N-terminal amino acid sequences to each other. Their hemagglutination activities were not inhibited by monosaccharides, but inhibited by glycoproteins bearing high-mannose N-glycans. In a binding experiment with pyridylaminated oligosaccharides by centrifugal ultrafiltration-HPLC assay, the isolectin KSA-2 was exclusively bound to high-mannose type N-glycans, but not to other glycans. Including complex types and a pentasaccharide core of N-glycans, indicating that it recognized branched oligomannosides. The binding activity of KSA-2 was slightly different among high-mannose N-glycans examined, indicating that the lectin has a higher affinity for those having the exposed (α1–3) Man in the D2 arm. On the other hand, KSA-2 did not bind to a free oligomannose that is a constituent of the branched oligomannosides, implying that the portion of the core GlcNAc residue(s) of the N-glycans is also essential for binding. Thus, KSA-2 appears to recognize the extended carbohydrate structure with a minimal length of a tetrasaccharide, Man(α1–3)Man(α1–6)Man(β1–4)GlcNAc. This study indicates that K. striatum, which has extensively been cultivated as a source of carrageenan, is a good source of a valuable lectin(s) that is strictly specific for high-mannose N-glycans.

Biochemical comparison of lectins among three different color strains of the red alga Kappaphycus alvarezii

The red alga Kappaphycus alvarezii is economically important as an edible species and as a source of carrageenan, and has been extensively cultivated in many tropical countries. For this species, different color strains, which differ from each another in growth rate and carrageenan content, have been reported for decades. In this study, lectins from brown, red, and green strains of K. alvarezii cultivated in Vietnam were isolated and characterized for evaluation of their biochemical properties and contents. The results showed that each color strain contained in common the three lectins, named KAA-1, KAA-2, and KAA-3, which shared the hapten-inhibition profile of hemagglutination, 20 N-terminal amino acid sequence, and equivalent molecular mass within a range of 28,016 ± 1.2 to 28,021 ± 1.8 Da, but differed in their yields, with the highest yield of KAA-2. These properties of the three isolectins were also comparable among the three different color strains. However, the sum of the yields of the three isolectins decreased in the order: red (21.4 mg) to green (15.9 mg) to brown strains (15.1 mg), from 500 g fresh alga. Thus, this algal species can be a good source of useful lectins, irrespective of color strain.

Pharmacologically-Active Amines in Some Marine Algae and Algal Food Products

Pharmacologically-active amines such as histamine and hordenine are of limited occurrence in European marine algae. However, hey are present in high levels in some algae used as a source of gelling agents. Histamine occurs at 600 Lo 2500 pg/g dry weight in Furcellaria lumbricalis which is the source of furcellaran. Hordenine occurs at 1000 to 5500 pg/g dry weight in Mastocarpus stellatus, which together with Chondrus crispus is the source of carrageenan. These latter two algae are also used to produce the algal food product Carrageen. However the traditional practice of bleaching Carrageen in the open reduces its hordenine content to a level which is unlikely to be hazardous in humans.

Sebdenia polydactyla—a novel source of carrageenan

The polysaccharide extracted from S. Polydactyla with sodium hydrogen carbonate at 90° accounted for 32% of the dry weight of the alga. It was ch

The evaluation of some red marine algae as a source of carrageenan and of its k- and lambda-components.

AbstractThe red seaweeds, Chondrus crispus, Gigartina stellata, G. radula, G. acicularis, G. pistillata, Eucheuma spinosum, and Polyides rotundus, have been evaluated as a source of carrageenan and of its k‐ and λ‐components. The fractionation of carrageenan from C. crispus with potassium ions does not always give a sharp separation into ‘pure’ k‐ and λ‐components and is dependent on habitat. Seasonal variations in total yield, k/λ ratio, optical rotation and chemical composition were observed.G. stellata and G. radula give poor separations but G. acicularis and G. pistillata give sharp fractionations and the proportion of λ‐polysaccharide in these two species is much higher than that in C. crispus. Approximately 30% of the dry weight of these seaweeds is λ‐carrageenan.Carrageenan from E. spinosum cannot be fractionated with potassium ions. This polysaccharide, which accounts for ˜55% of the dry weight of the seaweed, is structurally related to k‐carrageenan but has a higher sulphate ester content. The extract of P. rotundus is also insensitive to potassium ions but differs from that of E. spinosum in having a negligible content of 3,6‐anhydrogalactose.Different carrageenans have been depolymerised to give products of low viscosity and high sulphate content. This was achieved in the case of k‐carrageenan and carrageenan from E. spinosum by mild treatment with acid. Two methods are described for λ‐carrageenan; the first involves oxidation with periodate, reduction with borohydride, and mild acid hydrolysis. The second method, which is cheaper and more effective, employs hypochlorite as oxidant. A series of degraded products is listed.