scholarly journals IMMUNOCYTOCHEMICAL LOCALIZATION OF THE EXTRACELLULAR POLYSACCHARIDE ALGINIC ACID IN THE BROWN SEAWEED, FUCUS DISTICHUS

1972 ◽  
Vol 20 (5) ◽  
pp. 358-367 ◽  
Author(s):  
VALERIE VREELAND
Keyword(s):  
Brown Seaweed ◽  
Extracellular Polysaccharide ◽  
Degree Of Polymerization ◽  
Extracellular Polysaccharides ◽  
Acidic Polysaccharide ◽  
Antibody Staining ◽  
Mannuronic Acid ◽  
Guluronic Acid ◽  
Fucus Distichus ◽  
Acid Ratio

Fluorescent and peroxidase-labeled antibody techniques were employed to localize alginate, which is one component in the complex extracellular acidic polysaccharide situation of the brown seaweed, Fucus distichus. The alginate antigen was extracted and characterized by a variety of methods. It had a low degree of polymerization and a mannuronic acid to guluronic acid ratio of 2.2. No contaminants were detected. The specificity of rabbit antisera was tested by immunodiffusion. Antisera reacted with alginate and fractions of alginate but not with other brown algal polysaccharides. When cryostat sections of Fucus proved unsuitable, 1-µ sections embedded in glycol methacrylate were used for indirect fluorescent or peroxidase antibody staining. Highly sulfated extracellular polysaccharides and intracellular phenolic compounds were implicated in nonspecific staining. Texture artifacts were caused by solubility of alginates and other polysaccharides from embedded sections. Alginate was localized in variable patterns in all cell walls and some matrix regions. The applicability of the methods is discussed.

The Fine Structure of Alginic Acid Components

1968 ◽  
Vol 26 ◽  
pp. 82-83
Author(s):  
S. Inoue ◽  
Y. Tanaka ◽  
S.C. Skoryna
Keyword(s):  
Fine Structure ◽  
Sodium Alginate ◽  
Uronic Acid ◽  
Alginic Acid ◽  
Brown Seaweed ◽  
Uronic Acids ◽  
Laminaria Hyperborea ◽  
Mannuronic Acid ◽  
Guluronic Acid ◽  
Hydrolysis Of

Sodium alginate, a brown seaweed polysaccharide, is capable of preventing intestinal absorption of radioactive strontium and its radiotoxicological importance is now well established. Alginic acid was found to be composed of 1,4-linked poly-L-guluronic acid and poly-D-mannuronic acid chains with some glycosidic linkages between these uronic acids.Polyguluronic and polymannuronic acid were prepared by acid hydrolysis of alginic acid from Laminaria hyperborea followed by fractionation of the partially degraded sodium alginate at pH 2.8. These components consist almost exclusively of a single uronic acid (polyguluronic acid: man/gul = 0.27; polymannuronic acid: man/gul = 10.7). Sodium polyguluronate inhibits absorption of radiostrontium more effectively than sodium polymannuronate.

scholarly journals Effects of Molecular Weight and Guluronic Acid/Mannuronic Acid Ratio on the Rheological Behavior and Stabilizing Property of Sodium Alginate

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4374 ◽  
Author(s):  
Wenxiao Jiao ◽  
Wenxue Chen ◽  
Yuqi Mei ◽  
Yonghuan Yun ◽  
Boqiang Wang ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Zeta Potential ◽  
Apparent Viscosity ◽  
Stability Index ◽  
Acid Modification ◽  
Mannuronic Acid ◽  
Guluronic Acid ◽  
Acid Ratio ◽  
Pseudoplastic Liquid ◽  
G Ratio

The aim of this study was to prepare sodium alginates (SAs) with different molecular weight and G/M ratio, and characterize their rheological behaviors and emulsifying properties. The result of Fourier transform infrared (FTIR) showed that the chemical bonds among the β-d-mannuronic acid- (M-), α-l-guluronic acid- (G-), and MG-sequential blocks in the SA chains were not changed significantly by acid treatment. Meanwhile, the molecular weight and G/M ratio of the SA exhibited drastic variation after acid modification. The result of rheological analysis suggesting that the apparent viscosity of SA reduced from 30 to 16.4 mPa.s with the increase of shear rate, reveals that SA solution belongs to pseudoplastic liquid. Also, the apparent viscosity of acid-modified SA solution dropped rapidly with the decrease of the molecular weight. The properties of emulsions stabilized by SA, SA-Ms, and commercial SAs were evaluated via the interface tensiometry and determination of the zeta potential, droplet size, creaming index (CI), and Turbiscan stability index (TSI). Compared with the SA-stabilized emulsion, the interfacial tension of the emulsion stabilized by SA-M increased with the decrease of the molecular weight reduced at the similar M/G ratio. The decrease in zeta potential and the increase in TSI of the emulsion were observed with the decrease of molecular weight, indicating that molecular weight plays an important role on the emulsifying ability of SA. In addition, the SA with low G/M ratio can form emulsions with stable and fine droplets.

A Developmental Study of Artificial Skin Using the Alginate Dermal Substrate

2007 ◽  
Vol 342-343 ◽  
pp. 125-128 ◽  
Author(s):  
Dae Hwan Park ◽  
Won Seok Choi ◽  
Sean Hyuck Yoon ◽  
Jung Soo Shim ◽  
Chul Hong Song
Keyword(s):  
Wound Healing ◽  
Brown Seaweed ◽  
Control Group ◽  
Developmental Study ◽  
Purification Method ◽  
Mannuronic Acid ◽  
Guluronic Acid ◽  
Complex Group ◽  
Thickness Skin ◽  
Dorsal Area

Alginate, which is isolate from brown seaweed, a bioabsorbable long chain polysaccharides of guluronic acid and mannuronic acid. The authors produced alginate, fibroblastgrowth- factor mixed alginate and alginate-collagen complex as a disc form. For study of wound healing, full thickness skin defects were made on the dorsal area of the animal model. And then alginate, fibroblast-growth-factor mixed alginate, alginate-collagen complex, vaseline gauze as control were applied on the wound and evaluated grossly and histopathologically. For biocompatibility test, alginate and alginate-collagen complex discs were implanted on back of New Zealand white rabbits. And we measured size of wound healing, size of wound epithelization, size of wound contracture at 5, 10, 15, 20, and 25 days. Four weeks after implantation, implanted animals were examined immunologically against alginate and collagen. Alginate and FGF-mixed alginate, alginate-collagen complex group showed statistically higher percentage of wound contraction and wound healed than control group(p<0.05) Alginate-collagen complex group and FGF-mixed alginate group showed statistically higher percentage of wound healed than alginate group. In conclusion, high-purified alginate from seaweeds by our purification method, has the ability of wound healing and addition of FGF or collagen increase the ability of alginate, it shows the possibility of alginate as dermal substrate.

scholarly journals Purification and Characterization of a Novel Endolytic Alginate Lyase from Microbulbifer sp. SH-1 and Its Agricultural Application

Marine Drugs ◽  
2020 ◽  
Vol 18 (4) ◽  
pp. 184 ◽  
Author(s):  
Jin Yang ◽  
Dandan Cui ◽  
Diwen Chen ◽  
Wenkang Chen ◽  
Shuo Ma ◽  
...  
Keyword(s):  
Specific Activity ◽  
Chilling Stress ◽  
Alginate Lyase ◽  
Vital Role ◽  
Acidic Polysaccharide ◽  
Mannuronic Acid ◽  
Guluronic Acid ◽  
Alginate Oligosaccharides ◽  
Agricultural Applications ◽  
Ph Range

Alginate, an important acidic polysaccharide in marine multicellular algae, has attracted attention as a promising biomass resource for the production of medical and agricultural chemicals. Alginate lyase is critical for saccharification and utilization of alginate. Discovering appropriate and efficient enzymes for depolymerizing alginate into fermentable fractions plays a vital role in alginate commercial exploitation. Herein, a unique alginate lyase, AlgSH7, belonging to polysaccharide lyase 7 family is purified and characterized from an alginate-utilizing bacterium Microbulbifer sp. SH-1. The purified AlgSH7 shows a specific activity of 12,908.26 U/mg, and its molecular weight is approximately 66.4 kDa. The optimal temperature and pH of AlgSH7 are 40 °C and pH 9.0, respectively. The enzyme exhibits stability at temperatures below 30 °C and within an extensive pH range of 5.0–9.0. Metal ions including Na+, K+, Al3+, and Fe3+ considerably enhance the activity of the enzyme. AlgSH7 displays a preference for poly-mannuronic acid (polyM) and a very low activity towards poly-guluronic acid (polyG). TLC and ESI-MS analysis indicated that the enzymatic hydrolysates mainly include disaccharides, trisaccharides, and tetrasaccharides. Noteworthy, the alginate oligosaccharides (AOS) prepared by AlgSH7 have an eliciting activity against chilling stress in Chinese flowering cabbage (Brassica parachinensis L.). These results suggest that AlgSH7 has a great potential to design an effective process for the production of alginate oligomers for agricultural applications.

scholarly journals Antioxidant potential and optimization of production of extracellular polysaccharide by Acinetobacter indicus M6

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Ch. Ravi Teja ◽  
Abraham P. Karlapudi ◽  
Neeraja Vallur ◽  
K. Mamatha ◽  
D. John Babu ◽  
...  
Keyword(s):  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Basal Medium ◽  
Extracellular Polysaccharide ◽  
Extracellular Polysaccharides ◽  
Scavenging Activity ◽  
Promising Alternative ◽  
Food Engineering ◽  
The Face

Abstract Background Extracellular polysaccharides (ECPs) produced by biofilm-producing marine bacterium have great applications in biotechnology, pharmaceutical, food engineering, bioremediation, and bio-hydrometallurgy industries. The ECP-producing strain was identified as Acinetobacter indicus M6 species by 16S rDNA analysis. The polymer produced by the isolate was quantified and purified and chemically analyzed, and antioxidant activities have been studied. The face-centered central composite design (FCCCD) was used to design the model. Results The results have clearly shown that the ECP was found to be endowed with significant antioxidative activities. The ECP showed 59% of hydroxyl radical scavenging activity at a concentration of 500 μg/mL, superoxide radical scavenging activity (72.4%) at a concentration of 300 μg/mL, and DPPH˙ radical scavenging activity (72.2%) at a concentration of 500 μg/mL, respectively. Further, HPLC and GC-MS results showed that the isolated ECP was a heteropolymer composed of glucose as a major monomer, and mannose and glucosamine were minor monomers. Furthermore, the production of ECP by Acinetobacter indicus M6 was increased through optimization of nutritional variables, namely, glucose, yeast extract, and MgSO4 by “Response Surface Methodology”. Moreover the production of ECP reached to 2.21 g/L after the optimization of nutritional variables. The designed model is statistically significant and is indicated by the R2 value of 0.99. The optimized medium improved the production of ECP and is two folds higher in comparison with the basal medium. Conclusions Acinetobacter indicus M6 bacterium produces a novel and unique extracellular heteropolysaccharide with highly efficient antioxidant activity. GC-MS analyses elucidated the presence of quite uncommon (1→4)-linked glucose, (1→4)-linked mannose, and (→4)-GlcN-(1→) glycosidic linkages in the backbone. The optimized medium improved the production of ECP and is two folds higher in comparison with the basal medium. The newly optimized medium could be used as a promising alternative for the overproduction of ECP.

In situ studies on alginic acid synthesis and other aspects of the metabolism of Laminaria digitata

1972 ◽  
Vol 50 (1) ◽  
pp. 177-184 ◽  
Author(s):  
Johan A. Hellebust ◽  
Arne Haug
Keyword(s):  
Amino Acids ◽  
Time Course ◽  
Alginic Acid ◽  
Acid Synthesis ◽  
Short Term ◽  
Fresh Weight Basis ◽  
Mannuronic Acid ◽  
Guluronic Acid ◽  
Rate Of Photosynthesis

Amino acids, particularly alanine and aspartate, become more strongly labeled than mannitol in short-term 14C-photoassimilation experiments. The amino acids are the most likely sources of carbon for alginic acid synthesis and respiration in the dark, in contrast to mannitol, which appears to be relatively unavailable. Temperature is very important in determining the rate of loss of recent photoassimilate in L. digitata. The rate of photosynthesis, on a fresh weight basis, is much higher for blades than for stipes.The time course for incorporation of photoassimilated carbon into alginate differs for the stipe and blade both in light and dark periods. Very little 14C enters alginate in blades in the dark, while alginate in stipes acquires considerable amounts of activity during dark periods. Alginate in both blade and stipe acquires 14C predominantly in mannuronic acid residues of their alginate during short-term photoassimilation periods, while guluronic acid residues become relatively more rapidly labeled during dark periods.

Photosynthesis, translocation, and alginic acid synthesis in Laminaria digitata and Laminaria hyperborea

1972 ◽  
Vol 50 (1) ◽  
pp. 169-176 ◽  
Author(s):  
Johan A. Hellebust ◽  
Arne Haug
Keyword(s):  
Time Course ◽  
Alginic Acid ◽  
Acid Synthesis ◽  
Laminaria Hyperborea ◽  
Short Term ◽  
Fresh Weight Basis ◽  
Mannuronic Acid ◽  
Guluronic Acid ◽  
Isolated Cortex ◽  
Photosynthetic Capacities

New and old tissues of L. digitata blades have very similar photosynthetic capacities on a fresh weight basis. Very little of the photoassimilate goes into alginic acid, or other macromolecular substances in old blade tissues. Less than 1% of the photoassimilated 14C in the old blade portion of a L. digitata blade was translocated to the new blade tissues in a 5-h experiment. In contrast, there is rapid transport of photoassimilate from bark cells to cells of the underlying tissues of L. digitata and L. hyperborea stipe sections. Isolated cortex and medulla tissues of L. digitata stipes have significant photosynthetic capacities, but are probably so strongly shaded by the darkly pigmented bark cells that little photosynthesis can normally occur in these tissues.A larger proportion of the photoassimilated carbon enters alginate in the cortex and medulla than in the bark of L. digitata and L. hyperborea stipes in short-term experiments. The time course for incorporation of photosynthate into alginate in continuous and pulse-labeling experiments indicates the presence of relatively large pools of alginate precursors. A large proportion of the total 14C incorporated into alginate in short-term experiments is found in the "M–M" (mannuronic acid) and "M–G" (alternating mannuronic and guluronic acid) block components.

Strain distribution and in planta production of an extracellular polysaccharide depolymerase from Bradyrhizobium japonicum

1992 ◽  
Vol 38 (8) ◽  
pp. 857-861 ◽  
Author(s):  
Michael F. Dunn ◽  
Arthur L. Karr
Keyword(s):  
Bradyrhizobium Japonicum ◽  
Root Nodules ◽  
Extracellular Polysaccharide ◽  
Extracellular Polysaccharides ◽  
Neutral Sugar ◽  
In Planta ◽  
In Vitro Production ◽  
Polysaccharide Composition ◽  
Vitro Production

Thirty-four strains of Bradyrhizobium japonicum were screened for the in vitro production of an extracellular polysaccharide depolymerase active against the B. japonicum acidic extracellular polysaccharide that contains mannose, glucose, galactose, and 4-O-methylgalactose as neutral sugar components. Over 90% of tested strains producing this type of extracellular polysaccharide also produced the extracellular polysaccharide depolymerase, whereas strains producing a compositionally different extracellular polysaccharide did not. In addition, representatives of species related to B. japonicum by extracellular polysaccharide composition or host range were also phenotypically depolymerase negative. Depolymerase was also present in soybean root nodules formed by B. japonicum strain 2143. In contrast to the cell-associated depolymerase activity found in free-living cells of this strain, most of the depolymerase activity present in nodules is free of the bacteroids. The widespread occurrence of the depolymerase among B. japonicum strains and the spatiotemporal distribution of its activity in planta are consistent with the enzyme playing a role in the removal of surface extracellular polysaccharide from the microorganism during the infection of nodulation process. Key words: Bradyrhizobium japonicum, soybean, extracellular polysaccharides, extracellular polysaccharide depolymerase, bacteroids.

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