PHOTOSYNTHESIS AND METABOLISM IN MARINE ALGAE: IV. THE FATE OF C14-MANNITOL IN FUCUS VESICULOSUS

1962 ◽  
Vol 40 (6) ◽  
pp. 803-807 ◽  
Author(s):  
R. G. S. Bidwell ◽  
N. R. Ghosh

C14-mannitol was supplied to fronds of F. vesiculosus, and its conversion into CO2 and other compounds was studied. Only small amounts of the mannitol taken in were metabolized. Mannitol is apparently not an immediate substrate of respiration, but in time it may be converted into some other substances which are. Dilute acid-soluble polysaccharides acquired small amounts of radioactivity, but most of the mannitol which underwent metabolism was eventually converted to residual carbohydrates. It is concluded that mannitol is probably a storage compound rather than an active metabolite.

1967 ◽  
Vol 45 (9) ◽  
pp. 1557-1565 ◽  
Author(s):  
R. G. S. Bidwell

Samples of Fucus vesiculcsus fronds were permitted to assimilate 14CO2 for 5 h and were then maintained in alternating periods of light and darkness for 3 days. Samples were collected at intervals, and the radioactivity of various simple and complex compounds was measured. The major product of photosynthesis was mannitol; relatively small amounts of 14C entered other compounds. From its behavior, it appears that mannitol is the major substrate of respiration in these plants; there may be secondary substrates among the complex polysaccharides. The complex polysaccharides are not formed directly from mannitol in light, but from some common precursors, or else from a small isolated pool of mannitol which is separated from the main cellular supplies. In darkness, the complex polysaccharides appear to be derived from stored mannitol. One of the more active metabolites, judged from its behavior, is a component of the residue left after dilute acid and sodium carbonate extraction. This component undergoes turnover, i.e. breakdown and resynthesis from newly-acquired photosynthate in the light, and is formed from stored photosynthate in the darkness.


1964 ◽  
Vol 42 (1) ◽  
pp. 23-33 ◽  
Author(s):  
J. S. Craigie ◽  
J. McLachlan

Normal, healthy thalli of Fucus vesiculosus have been shown to release into the surrounding medium yellow compounds which absorb ultraviolet light. A study of this phenomenon revealed that brief exposure to elevated temperatures (20 °C) increased the amount of pigment released. There was no difference in the production in light or darkness and only a small decrease with reduced salinity. The amount of pigmentation observed in the medium was directly proportional to the degree of alkalinity from pH 7 to pH 9.A number of other macrophytes and microphytes were examined and only those possessing physodes released substances giving a spectrum similar to that of F. vesiculosus.Isolation of the material, alkaline hydrolysis, and chromatography revealed phloroglucinol and several unidentified fluorescent substances. It appears that these materials were flavonols or catechin-type tannins.


1972 ◽  
Vol 50 (1) ◽  
pp. 191-197 ◽  
Author(s):  
R. G. S. Bidwell ◽  
Elizabeth Percival ◽  
Berit Smestad

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.


Author(s):  
CHANDRA VELUCHAMY ◽  
RADHA PALANISWAMY

The ocean is the major essential source of structurally unique natural products that are mainly present in living organisms. The essential products extracted from marine microbes and marine algae are highly analyzed areas in instinctive product research. Marine algae are the novel food with potential nutritional values used for multiple purposes in industry and medicine. They show pharmacological activities which are helpful for the invention of bioactive compounds. Furthermore, marine algae have shown to provide an abundant source of natural bioactive compounds with antidiabetic, anti-inflammatory, antiviral, antifungal, hypolipidemic, antioxidant, anti-hypercholesterolemia, antibacterial, and antineoplastic properties. They produce new secondary metabolites that possess biological activities and have the potential to be developed as therapeutic agents. Macroalgal lectins, fucoidans, kainoids, and other substances have been routinely used in the research of biomedical and also have biological activities. The potential pharmaceutical, medicinal, and research applications of these compounds are discussed.


1963 ◽  
Vol 41 (1) ◽  
pp. 155-163 ◽  
Author(s):  
R. G. S. Bldwell ◽  
N. R. Ghosh

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.


2016 ◽  
Vol 2 (1) ◽  
pp. 27
Author(s):  
Emin Cadar ◽  
Cristina Luiza Erimia ◽  
Aneta Tomescu ◽  
Stelian Paris ◽  
Rodica Sîrbu

During the past years, it became obvious that the ecosystem presents a marine algae surpluses, which should be turned valuable in one way or another. The importance of the macrobenthic flora – algae and phanero-gammes – for the general productivity of the marine environment, especially in shallow waters, is becoming more and more obvious from the biological as well as from the economical point of view. The macrophytes also represent a particular life form. The benthic macroflora includes 33 species 4: 16 Chlorophyta, 10 Rhodophyta, 5 Phaeophyta, and 2 Phanerogama. The quantity of green algae (Chlorophyta) was higher in the Constanta – Eforie area, as red algae are predominant in the southern part of the littoral. Brown algae (Phaeophyta) were encountered in the Constanta city area (Punctaria) and in Vama-Veche (Cystoseira barbata). Yet, this fact indicates a slight amelioration of the marine ecosystem, after many years of eutrophication. The superior capitalisation of the marine biomass represents a highly important resource for the pharmaceutical industry, supplying raw material for the extraction of bioactive substances and various other substances, the purity of which is strongly connected to the state of the marine ecosystem.


2016 ◽  
Vol 4 (1) ◽  
pp. 27
Author(s):  
Emin Cadar ◽  
Cristina Luiza Erimia ◽  
Aneta Tomescu ◽  
Stelian Paris ◽  
Rodica Sîrbu

During the past years, it became obvious that the ecosystem presents a marine algae surpluses, which should be turned valuable in one way or another. The importance of the macrobenthic flora – algae and phanero-gammes – for the general productivity of the marine environment, especially in shallow waters, is becoming more and more obvious from the biological as well as from the economical point of view. The macrophytes also represent a particular life form. The benthic macroflora includes 33 species 4: 16 Chlorophyta, 10 Rhodophyta, 5 Phaeophyta, and 2 Phanerogama. The quantity of green algae (Chlorophyta) was higher in the Constanta – Eforie area, as red algae are predominant in the southern part of the littoral. Brown algae (Phaeophyta) were encountered in the Constanta city area (Punctaria) and in Vama-Veche (Cystoseira barbata). Yet, this fact indicates a slight amelioration of the marine ecosystem, after many years of eutrophication. The superior capitalisation of the marine biomass represents a highly important resource for the pharmaceutical industry, supplying raw material for the extraction of bioactive substances and various other substances, the purity of which is strongly connected to the state of the marine ecosystem.


1963 ◽  
Vol 41 (3) ◽  
pp. 317-325 ◽  
Author(s):  
J. S. Craigie

The ability of several multicellular marine algae to remove NaHC14O3 from seawater in darkness has been compared. Members of the Phaeophyta removed approximately four to eight times more isotope than did members of the Rhodophyta and Chlorophyta examined. After 2 minutes of dark fixation, aspartic and glutamic acids were the main compounds identified in both Fucus vesiculosus and Polysiphonia lanosa. Radioactivity appeared largely in citric plus isocitric acids in Fucus, whereas radioactive organic acids were not detected in Polysiphonia even after 30 minutes. Fractionation of F. vesiculosus after 2 hours of dark fixation showed that 95% of the total radioactivity recovered occurred in the fraction soluble in 70% acetone.Twenty-four hours of darkness immediately prior to a 2-hour dark fixation period reduced the total radioactivity incorporated to almost one-half of the control values. Either artificial seawater (one-fifth natural salinity) or a medium in which NaCl was substituted by KCl had little effect on the total radioactivity fixed during darkness. The distribution of isotope, however, showed some alterations.


2018 ◽  
Vol 10 ◽  
pp. 01007
Author(s):  
Ewa Jachniak ◽  
Joanna Chmura ◽  
Mariusz Kuglarz ◽  
Józef Wiktor

The aim of the research was to try to obtain of the biogas on a laboratory scale from marine algae biomass and water plant biomass. The research was conducted in 2016 year and samples were taken from the Polish coast of the Baltic Sea. In laboratory work, algae and plant species were first identified. The next, in order to subject them to methane fermentation processes and to obtain biogas,partial mechanical treatment of the biomass was conducted. Dry matter content and dry organic matter content were also determined. The research has shown different production of the biogas depending on the various species of the algae and plants. The percentage composition of the biogas was also determined (% CO2 and % CH4). In this research some kinds and species of algae and aquatic plants were distinguished: Scytosiphon cf. S. tortilis, Fucus vesiculosus, Cladophora, Audouinella, Potamogeton perfoliatus. Production of biogas from selected algae and water plants oscillated between 0.023 dm3·g-1 and 0.303 dm3·g-1. The highest content of the methane in biogas was obtained from the mixture of Ectocarpus from spring and autumn harvest (values oscillated from 80.7 % to 81.2 %), while the highest percentage share of carbon dioxide in the biogas was characterized by the mixture Fucus vesiculosus and Audouinella (22 %). Due to a small amount of the research in this field, more research is needed.


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