Photosynthesis and metabolism of marine algae. VIII. Incorporation of 14C into the polysaccharides metabolized by Fucus vesiculosus during pulse labeling experiments

1972 ◽  
Vol 50 (1) ◽  
pp. 191-197 ◽  
Author(s):  
R. G. S. Bidwell ◽  
Elizabeth Percival ◽  
Berit Smestad
Keyword(s):  
Molecular Weight ◽  
Sequential Extraction ◽  
Marine Algae ◽  
Alginic Acid ◽  
Fucus Vesiculosus ◽  
Fresh Medium ◽  
Low Molecular Weight ◽  
Acid Extract ◽  
Highly Active ◽  
Residual Material

Samples of Fucus vesiculosus fronds were allowed to assimilate 14CO2 for 10 min and 3 h. In a second experiment fronds were allowed to grow for 10 min in 14CO2 and were then transferred to fresh medium containing 12CO2. Samples were taken immediately, after 30 min, and after 2 h. Sequential extraction and fractionation of the polysaccharides from each of the five samples gave 14C-labeled laminaran, xylogalactofucoglucuronan (A), xyloglucuronogalactofucan (B) (these polysaccharides are named in the order of the increasing proportions of their constituent sugars), fucoidan (C), alginic acid, and residual polysaccharide material containing mainly glucose with some galactose. The activities of each of the polysaccharides, the residual material, and their constituent sugars were measured. Highly active low molecular weight carbohydrates, present in the acid extract, are the suggested precursors of the polysaccharides. The fucose-containing polysaccharides represent the extremes of a family of polymers; it is postulated from these studies that (A) is transformed into fucoidan via polysaccharide (B) in this alga.

scholarly journals Determination of 11 Low-Molecular-Weight Carbonyl Compounds in Marine Algae by High-Performance Liquid Chromatography

2006 ◽  
Vol 44 (5) ◽  
pp. 233-238 ◽  
Author(s):  
V. M. da Silva ◽  
M. C. da Cunha Veloso ◽  
E. T. Sousa ◽  
G. Vieira Santos ◽  
M. C. Accioly ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Carbonyl Compounds ◽  
High Performance ◽  
Marine Algae ◽  
Low Molecular Weight

scholarly journals Chemical constituents of the physodes of brown algae. Characterization by 1H and 13C nuclear magnetic resonance spectroscopy of oligomers of phloroglucinol from Fucus vesiculosus (L.)

1977 ◽  
Vol 55 (9) ◽  
pp. 1575-1582 ◽  
Author(s):  
James S. Craigie ◽  
A. Gavin McInnes ◽  
Mark A. Ragan ◽  
John A. Walter
Keyword(s):  
Molecular Weight ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Chemical Constituents ◽  
Fucus Vesiculosus ◽  
Resonance Spectroscopy ◽  
Low Molecular Weight ◽  
13C Nuclear Magnetic Resonance ◽  
C Nmr

Alcoholic extracts of Fucus vesiculosus contain small quantities of low molecular weight polyphenols derived from phloroglucinol and 2,2′,4,4′,6,6′-hexahydroxybiphenyl. 1H and 13C nmr were used to identify two of these as 4-(2′′,4′′,6′′-trihydroxyphenoxy)-2,2′,4′,6,6′-pentahydroxybiphenyl and 4-(2′′-(2′′′,4′′′,6′′′-trihydroxyphenoxy)-4′′,6′′-dihydroxyphenoxy)-2,2′,4′, 6,6′-pentanydroxybiphenyl.

scholarly journals The nature of conditioning nutrients for human malignant melanoma cultures

1983 ◽  
Vol 62 (1) ◽  
pp. 249-266
Author(s):  
K.A. Ellem ◽  
G.F. Kay
Keyword(s):  
Molecular Weight ◽  
Cell Density ◽  
Cell Attachment ◽  
Cell Types ◽  
Fresh Medium ◽  
Low Molecular Weight ◽  
High Concentration ◽  
Cell Content ◽  
Human Malignant Melanoma ◽  
Serum Factors

From a human melanoma line (MM96), showing some dependence of its rate of growth and cell attachment on serum concentration, sublines were selected for even greater dependence on serum factors. These sublines were used to identify the production of substances by other melanoma cells in culture that would supplement or replace the requirement for serum. Most of the sublines showed higher colony-forming efficiency in medium conditioned by one of several cell types in the presence of a low concentration of serum (2.5%) compared with fresh medium containing a high concentration of serum (10%). The conditioning factor(s) were found to be moderately heat-stable, nonlipophilic, and to be of low molecular weight (less than or greater than 400). Screening of a variety of non-essential low molecular weight nutrients, which have been reported to potentiate the growth of a variety of cell types in low-density culture, was positive for the MM96 sublines only for pyruvate. In particular, L-alanine, L-serine, putrescine and alpha MSH (melanocyte-stimulating hormone) were ineffective. Despite the problems of comparing conditioned media with fresh medium, a reasonable correlation between the stimulatory effect and the cell content of added 2-oxocarboxylates was apparent. As would be anticipated, MM96 cultures showed a population density-dependent enhancement of growth up to a cell density of 2 to 4 × 10(4) cells cm-2. Further increase in the initial cell density of these cultures led to a decline in growth rate. An important additional observation was that simple dilution of the ingredients of RPMI1640 with phosphate-buffered saline or Hanks' balanced salt solution led to a reversal of growth inhibition accompanying a serum shift-down.

Floc-Forming Substances Extracted from Activated Sludge with Ammonium Hydroxide and EDTA Solutions

1985 ◽  
Vol 17 (4-5) ◽  
pp. 517-528 ◽  
Author(s):  
T. Sato ◽  
Y. Ose
Keyword(s):  
Molecular Weight ◽  
Activated Sludge ◽  
Sequential Extraction ◽  
Ammonium Hydroxide ◽  
Low Molecular Weight ◽  
Metallic Ions

The authors attempted to extract the floc-forming substances by sequential extraction with NH4OH and EDTA solutions from activated sludge. Some fractions had the capacity for floc formation in acidic ranges and some of the fractions were further fractionated by Sephadex G-50. There is a possibility that low molecular weight substances, except metallic ions related to floc formation and floc-forming substances in activated sludge are not limited to one special substance.

PHOTOSYNTHESIS AND METABOLISM OF MARINE ALGAE: V. RESPIRATION AND METABOLISM OF C14-LABELLED GLUCOSE AND ORGANIC ACIDS SUPPLIED TO FUCUS VESICULOSUS

1963 ◽  
Vol 41 (1) ◽  
pp. 155-163 ◽  
Author(s):  
R. G. S. Bldwell ◽  
N. R. Ghosh
Keyword(s):  
Organic Acids ◽  
Marine Algae ◽  
Alginic Acid ◽  
Fucus Vesiculosus ◽  
Alcohol Extract ◽  
Sodium Salts ◽  
Uptake And Metabolism

Fronds of F. vesiculosus were supplied with glucose-UL-C14, pyruvate-2-C14, acetate-1-C14, acetate-2-C14, or formate-C14, the acids being presented as the sodium salts. The radioactivity of various fractions of the fronds as well as respired CO2 was determined after various times, and the distribution of radioactivity among the compounds present in the alcohol extract was determined. The contribution of glucose to respired CO2 was much less than that of the organic acids. However, although its uptake and metabolism were less, a large proportion of the glucose that was metabolized was converted to CO2. Glucose contributed somewhat to polysaccharides, but the organic acids were much better precursors of alginic acid. The pattern of labelling among soluble compounds, of which glycerol was especially prominent, indicated that several pathways of metabolism operated, involving both carboxylation and decarboxylation reactions.

Preparation of low-molecular weight alginic acid by acid hydrolysis

2000 ◽  
Vol 42 (4) ◽  
pp. 421-425 ◽  
Author(s):  
A. Ikeda ◽  
A. Takemura ◽  
H. Ono
Keyword(s):  
Molecular Weight ◽  
Acid Hydrolysis ◽  
Alginic Acid ◽  
Low Molecular Weight

scholarly journals Proteine als Schutzstoffe gegenüber dem Gefriertod der Zelle

1970 ◽  
Vol 25 (8) ◽  
pp. 834-842 ◽  
Author(s):  
U. Heber ◽  
M. Kempfle
Keyword(s):  
Molecular Weight ◽  
Frost Tolerance ◽  
Thylakoid Membranes ◽  
Weight Basis ◽  
Unit Weight ◽  
Low Molecular Weight ◽  
Complete Protection ◽  
Highly Active ◽  
Heat Stable ◽  
Better Than

Two protein factors from hardy leaves were highly active in preventing the inactivation of photophosphorylation of washed thylakoid membranes which takes place during freezing of thylakoids in the absence of protective compounds. Non-hardy leaves did not yield protective protein material. On a unit weight basis, protection by the protein factors was 10 to 100 times better than protection by compounds of low molecular weight such as sucrose, glycerol or dimethylsulfoxide. Very low amounts of the protein factors, which alone were scarcely protective, considerably reduced the concentration of sucrose required for the complete protection of thylakoids during freezing. The protein factors were heat-stable and had a molecular weight between 10 000 and 20 000 daltons. It is assumed that they contribute to and are in part responsible for the frost tolerance of hardy plant material.

scholarly journals POLYPHENOLS OF ARCTIC BROWN ALGAE: EXTRACTION, POLYMOLECULAR COMPOSITION

2019 ◽  
pp. 65-75
Author(s):  
Konstantin Grigor'yevich Bogolitsin ◽  
Anna Sergeyevna Druzhinina ◽  
Denis Vladimirovich Ovchinnikov ◽  
Anastasiya Eduardovna Parshina ◽  
Elena Valeriyevna Shulgina ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Molecular Weight ◽  
Brown Algae ◽  
Maximum Yield ◽  
Gel Filtration ◽  
Fucus Vesiculosus ◽  
Polyphenolic Compounds ◽  
Biologically Active ◽  
Low Molecular Weight ◽  
High Biological Activity

Arctic brown algae of the species Fucus vesiculosus are characterized by a high content of polyphenolic compounds - phlorotannins, exhibiting high biological activity. The aim of this study is to develop a methodology for the isolation and analysis of biologically active polyphenolic compounds from arctic brown algae. The proposed scheme for the isolation of polyphenols from Fucus vesiculosus brown algae is based on the principles of "green chemistry" and is carried out by sequential disassembly of the biomass of the plant object with the release of associated components (lipid-pigment complex, polysaccharides, mannitol) and maximum yield of polyphenol fraction. As a result of the experimental work, the optimal parameters for carrying out each stage of the proposed scheme were determined and a stepwise assessment of its effectiveness was carried out. The extractable fraction of polyphenols contains up to 67% of polyphenols relative to their content in the initial biomass, and the proportion of polyphenols in the fraction is up to 83%. A study of the phlorotannins fraction showed that its antioxidant activity is meaningful and it was 553±24 (mg of ascorbic acid/g extract). The polymolecular composition of the target fraction was investigated by the method of exclusion gel filtration chromatography, which showed the polymodal distribution, indicating the presence of several groups of components - low molecular weight and high molecular weight phlorotannins with masses ranging from thousands to hundreds of thousands of Daltons. The data obtained using chromatography-mass spectrometry and MALDI mass spectrometry make it possible to identify the presence of low molecular weight phlorotannins in the polyphenol fraction with masses from 250 to 1638 Da, which are close analogues in structure.

scholarly journals Influences of Fluorine Substituents on Iminopyridine Fe(II)- and Co(II)-Catalyzed Isoprene Polymerization

Polymers ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 934 ◽  
Author(s):  
Guangqian Zhu ◽  
Xianhui Zhang ◽  
Mengmeng Zhao ◽  
Liang Wang ◽  
Chuyang Jing ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Binary Systems ◽  
Low Molecular Weight ◽  
X Ray Diffraction ◽  
Molecular Weights ◽  
Highly Active ◽  
Iron Metal ◽  
Polymer Properties ◽  
Stereo Selectivity ◽  
Isoprene Polymerization

A series of iminopyridine complexes of Fe(II) and Co(II) complexes bearing fluorinated aryl substituents were synthesized for the polymerization of isoprene. The structures of complexes 3a, 2b and 3b were determined by X-ray diffraction analysis. Complex 3a contained two iminopyridine ligands coordinated to the iron metal center forming an octahedral geometry, whereas 2b adopted a chloro-bridged dimer, and 3b featured with two patterns of cobalt centers bridged via chlorine atoms. Complexes 2b and 3b represented rare examples of chlorine bridged bimetallic Co(II) complexes. The fluorine substituents effects, particularly on catalytic activity and polymer properties such as molecular weight and regio-/stereo-selectivity were investigated when these complexes were employed for isoprene polymerization. Among the Fe(II)/methylaluminoxane (MAO) systems, the 4-CF3 substituted iminopyridine Fe(II) complex 1a was found as a highly active isoprene polymerization catalyst exhibiting the highest activity of 106 g·(mol of Fe)−1·h−1. The resultant polymer displayed lower molecular weight (Mn = 3.5 × 104 g/mol) and moderate polydispersity index (PDI = 2.1). Furthermore, the ratio of cis-1,4-/3,4 was not affected by the F substituents. In the series of Co(II)/AlEt2Cl binary systems, complexes containing electron-withdrawing N-aryl substituents (R = 4-CF3, 2,6-2F) afforded higher molecular weights polyisoprene than that was obtained by the complex containing electron-donating N-alkyl substituents (R = octyl). However, ternary components system, complex/MAO/[Ph3C][B(C6F5)4] resulted in low molecular weight polyisoprene (Mn < 2000) with high trans-1,4-unit (>95%).

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