Content of alginic acid and fucoidan in fucus algae of the Barents sea

Seasonal changes in the content of alginic acid and fucoidan have been studied in four species of fucus algae from the Barents sea: Fucus vesiculosus, F. distichus, F. serratus, and Ascophyllum nodosum. These polysaccharides are accumulated in the biomass of the algae during summer and autumn. To ensure complete processing of fucus algae it is recommended that the raw material be harvested within this period.     

Comparative chemical composition of the Barents Sea brown algae

Comparative study of phytochemical compositions of the most widespread brown algae species (one laminarian and four fucoid algae) from Barents Sea has been performed. A modified technique for mannitol determination in brown algae is proposed. It was revealed that fucus algae (fam. Fucaceae) contain 3% (of total dry weight) less mannitol than laminaria (Laminaria saccharina). The contents of alginic acid and laminaran in the Barents Sea fucoids are more than 10% less compared to laminaria. The alga L. saccharina contains almost two times more iodine than the species of fam. Fucaceae. The amounts of fucoidan and sum lipids in the Barents Sea fucoid algae is higher than in Laminaria saccharina (4–7% and 1–3%, respectively). In terms of contents of main biologically active compounds, fucus and laminarian algae from Barents Sea are inferior to none of the Far-Eastern species. The Barents Sea algae may become an important source of biologically active compounds.     

Comparative chemical composition of the Barents Sea brown algae

Comparative study of phytochemical compositions of the most widespread brown algae species (one laminarian and four fucoid algae) from Barents Sea has been performed. A modified technique for mannitol determination in brown algae is proposed. It was revealed that fucus algae (fam. Fucaceae) contain 3% (of total dry weight) less mannitol than laminaria (Laminaria saccharina). The contents of alginic acid and laminaran in the Barents Sea fucoids are more than 10% less compared to laminaria. The alga L. saccharina contains almost two times more iodine than the species of fam. Fucaceae. The amounts of fucoidan and sum lipids in the Barents Sea fucoid algae is higher than in Laminaria saccharina (4-7% and 1-3%, respectively). In terms of contents of main biologically active compounds, fucus and laminarian algae from Barents Sea are inferior to none of the Far-Eastern species. The Barents Sea algae may become an important source of biologically active compounds.     

Effects of filamentous algae and deposited matter on the survival of Fucus vesiculosus L. germlings in the Baltic Sea

As a result of increased nutrient levels in the Baltic Sea during thepast 50 years, mass developments of filamentous algae have become a commonfeature along the Swedish east coast and deposition of organic matter has alsoincreased. To test whether these two factors have any effects on the early lifestages of Fucus vesiculosus a number of laboratory andfield studies were conducted. The amount of epilithic and epiphytic filamentousalgae on F. vesiculosus and the amount of deposited matterin the littoral zone were quantified during the two reproductive periods ofF. vesiculosus, early summer (May–June) and lateautumn (September–October). Both filamentous algae (Cladophoraglomerata) and deposited matter (introduced either before or aftersettlement of fertilized eggs) were shown to significantly decrease the numberof surviving germlings. The survival of germlings seeded on stones withfilamentous algae, or seeded on culture dishes concurrently with the lowestconcentration of deposited matter (0.1 g dm^–2),was 5% or less. In the field, the amount of filamentous algae was significantlyhigher during F. vesiculosus summer reproduction, whereasthe amount of deposited matter collected in traps was significantly higherduring the period of autumn reproduction. The greatest biomass of filamentousalgae was observed at sheltered sites. Based on the negative effects offilamentous algae and deposited matter on Fucusrecruitmentand the observation of local and seasonal differences in abundance offilamentous algae and deposition, we suggest that the prerequisites for thesurvival of either summer or autumn-reproducing populations of F.vesiculosus in the Baltic Sea may differ locally.     

Far‐red dependent changes in the chemical composition of Spirulina platensis

The influence of far‐red light (FRL) was studied on the chemical composition of Spirulina platensis biomass. The following light compositions were used during the culture white light, blue‐red LED light (BRL) and BRL supplemented with FRL (BRFRL). Chlorophyll and phenol contents were measured by spectrophotometric methods, whereas presence of carotenoids, lipids, and phycobiliproteins were estimated by Fourier‐transform Raman spectrometry. Additionally, phenol content was investigated by fluorescence intensity of algae culture in the range of 430–650 nm. The content of chlorophyll and phenols in algae cells depended on the spectral composition of light and was the highest under BRL (16.7 ± 0.5 and 9.1 ± 0.6, respectively). It was shown that there is a positive linear correlation (R = 0.902 at p < 0.0000001) between the ratio of relative fluorescence intensity of S. platensis suspensions at 450 nm to the suspensions at 540 nm (F450/F540) and the content of phenolic compounds in the biomass. Changes in the F450/F540 ratio can explain approximately 80% changes of phenol contents in algae cells. Spirulina platensis Raman spectra demonstrated that the biomass of algae growing under white light and BRL had a significantly higher intensity of phycobiliprotein bands than the algae growing under BRFRL.     

Functional properties of photosynthetic apparatus in three <Emphasis Type="Italic">Fucus</Emphasis> species inhabiting the White Sea: Effect of dehydration

Three species of Fucus inhabiting different zones at the littoral and sublittoral of the White Sea (F. vesiculosus L., F. serratus L., and F. distichus L.) were compared with regard to performance of the photosynthetic apparatus (PSA) and PSA changes upon prolonged desiccation of algae. The content of chlorophyll a and the total content of carotenoids were significantly higher in F. serratus than in F. vesiculosus. The potential quantum yield (F _v/F _m) of photosystem II (PSII) was 0.69–0.74 in all species. The highest effective quantum yield of PSII (Y _II) was observed in F. vesiculosus plants inhabiting zones with the most intense insolation. The ratio of non-photochemical quenching to photochemical quenching (qN/qP) increased with the depth of algal habitats in the row from F. vesiculosus to F. serratus. The fluorescence parameters F. serratus deviated during desiccation from their normal values and did not recover upon the subsequent return to water. By contrast, the fluorescence parameters of F. vesiculosus and F. distichus recovered gradually after the return of algae from air to sea water. It is supposed that F. serratus plants, unlike other species, are characterized by comparatively low physiological plasticity.     

Sucrose metabolism in green algae I. The presence of sucrose synthetase and sucrose phosphate synthetase

Summary The presence of sucrose synthetase and sucrose phosphate synthetase has been demonstrated in two species of green algae:Chlorella vulgaris andScenedesmus obliquus. Partial purification from crude extracts allowed the determination of the kinetic constants of algae enzymes. They are very similar to the ones reported for enzymes from higher plants.Dedicated toLuis F. Leloir on his seventieth birthday.     

The occurrence of Fosliella limitata (Foslie) Ganesan (a new British record) and F. lejolisii (Rosanoff) Howe (Rhodophyta,Corallinaceae) on the Isle of Wight

The occurrence of Fosliella limitata and F. lejolisii at Bembridge, Isle of Wight is reported. F. limitata is newly recorded for Britain whilst F. lejolisii has been found only rarely since disease struck Zostera in the early 1930s. The two epiphytes both grow on Zostera; F. limitata also grows on large brown and red algae. Their vegetative and reproductive structures are described and illustrated and information given regarding their seasonal occurrence from May 1975 to April 1976. Previous records of both species are discussed and a table is given summarizing the differences between the species.     

In situ study of relative electron transport rates in the marine macroalga <Emphasis Type="Italic">Fucus vesiculosus</Emphasis> in the Baltic Sea at different depths and times of year

The brown alga Fucus vesiculous is one of the few marine species in the Baltic Sea. Fucus vesiculosus shows high morphological and physiological variability as a response to its environmental conditions. The salinity in the Baltic Sea is 4–5 psu, compared to 35 psu in the Atlantic. Photosynthesis of algae is usually measured after collection and transportation to constant culture conditions. However, in this study, relative photosynthetic electron transport rates, calculated from chlorophyll a fluorescence parameters were compared in algae collected from 1 and 4 m depths by SCUBA divers. Measurements of light response curves from the same individuals of F. vesiculosus at different depths and times of the year have, to our knowledge, not been made previously. Measurements were performed on four different occasions during the spring of 2005 (25 February, 3 and 29 April, and 26 May) in the Baltic Sea, using rapid light curves generated with a Diving PAM. In addition, samples were collected for photoinhibition studies in the laboratory. The light response curves obtained in situ at 1 and 4 m depths for F. vesiculosus showed lower values of light saturation with depth. When algae from 1 and 4 m depths were exposed to high irradiances of photosynthetically active radiation (1,400 μmol photons m⁻² s⁻¹), algae from 1 m depth showed a higher degree of photoinhibition in comparison to algae from 4 m depth.     

Impacts of an Invasive N2‐Fixing Tree on Hawaiian Stream Water Quality

N₂‐fixing trees can affect stream water quality. This has been documented in temperate streams, but not in tropical ones, even though N₂‐fixing trees are prevalent in the tropics. We investigated the effects of the introduced, invasive tree, Falcataria moluccana (albizia) on water quality of Hawaiian streams. Nutrient concentrations were measured in reaches above and below F. moluccana‐dominated riparian zones of four streams over 14 mo, and benthic algal nutrient limitation was examined in one stream. NO₃^?+NO₂^? concentrations were up to 600 percent higher in reaches below F. moluccana stands than in ones above them. In contrast, dissolved organic nitrogen concentrations were 24 percent lower in most reaches below F. moluccana stands, and NH₄⁺ and particulate nitrogen concentrations were similar above and below the stands. Dissolved organic carbon concentrations were up to 30 percent lower below F. moluccana stands, but particulate carbon concentrations were similar between reaches. Total dissolved phosphorus concentrations were similar above and below F. moluccana stands, whereas H₄SiO₄ concentrations were higher below the stands. In the stream where benthic chlorophyll a was measured, concentrations were three times higher below the F. moluccana stand than above it. Benthic algae were co‐limited by nitrogen and phosphorus above the F. moluccana stand, and limited by phosphorus below it. These results suggest that F. moluccana's presence relieved nitrogen‐limitation and caused the benthic algae to become solely phosphorus‐limited. Overall, our results demonstrate that F. moluccana can strongly affect the chemistry and primary producers of these tropical streams.     

Examination of the structures of several glycerolipids from marine macroalgae by NMR and GC‐MS

Several classes of glycerolipids were isolated from the total lipids of the algae Saccharina cichorioides, Eualaria fistulosa, Fucus evanescens, Sargassum pallidum, Silvetia babingtonii (Ochrophyta, Phaeophyceae), Tichocarpus crinitus, and Neorhodomela larix (Rhodophyta, Florideophyceae). The structures of these lipids were examined by nuclear magnetic resonance (NMR) spectroscopy, including 1D (¹H and ¹³C) and 2D (COSY, HSQC and HMBC) experiments. All of the investigated algae included common galactolipids and sulfonoglycolipids as the major glycolipids. Minor glycolipids isolated from S. cichorioides, T. crinitus, and N. laris were identified as lyso‐galactolipids with a polar group consisted of the galactose. Comparison of the ¹H NMR data of minor nonpolar lipids isolated from the extracts of the brown algae S. pallidum and F. evanescens with the ¹H NMR data of other lipids allowed them to be identified as diacylglycerols. The structures of betaine lipids isolated from brown algae were confirmed by NMR for the first time. The fatty acid compositions of the isolated lipids were determined by gas chromatography‐mass spectrometry.     

Marine Brown Algae Requiring Vitamin B12

The brown algae Lithosiphon pusillus, Ectocarpus fasciculatus and Pylaiella litoralis were cultivated in bacteria-free cultures in artificial sea water, ASP 6F. The growth was tested with different additions of vitamins and other metabolites. Lithosiphon pusillus and Ectocarpus fasciculatus were found to require vitamin B₁₂ for optimal growth. The zoospores of Pylaiella litoralis, when cultured in medium Asp 6F with kinetin added, had an absolute requirement for vitamin B₁₂.     

On the validity of the genusDactylococcopsis (Cyanophyceae)

Summary The genusDactylococcopsis Hansg. 1888 (Cyanophyceae) is based on the typeD. rupestris, which was later identified as a green algae. Most of the many species described later were also placed to other groups of algae. Several authors even doubted about the existence of the genus. As, however, some species of Cyanophyceae correspond to the original generic diagnosis, the name Dactylococcopsis Hansg. ex R. et F.Chod. 1925 has been proposed as a nomen conservandum, and a new type (D. smithii R. et F.Chod.) has been defined. Further speciesD. linearis Geitl. 1935 and D.Planctonica Teil. 1942 has been unambiguously described till now.     

Low Divergence in rDNA ITS Sequences Among Five Species of Fucus (Phaeophyceae) Suggests a Very Recent Radiation

Sequences from the two ribosomal DNA internal transcribed spacers (ITS1 and ITS2) were compared among five species of Fucus. Based on the present taxon sampling, parsimony analysis showed that Fucus serratus is the sister-group of the remaining Fucus species when Ascophyllum nodosum was used as an outgroup. The topology of the tree was (Fucus serratus (F. lutarius (F. vesiculosus (F. spiralis+F. ceranoides)))). The extremely low variation observed suggests a very recent radiation of the genus which supports the view widely accepted that the Fucales are among the most evolutionarily advanced of the brown algae. We further note that sequence differences between Fucus and Ascophyllum were 28%: this does not rule out the utility of ITS sequences within the Fucaceae. The very low number of informative positions allows to demonstrate empirically that distance matrix methods group on the basis of symplesiomorphies. Received: 17 February 1997 / Accepted: 17 April 1997     

Different speciation for bromine in brown and red algae,revealed by in vivo X‐ray absorption spectroscopic studies

Members of various algal lineages are known to be strong producers of atmospherically relevant halogen emissions, that is a consequence of their capability to store and metabolize halogens. This study uses a noninvasive, synchrotron‐based technique, X‐ray absorption spectroscopy, for addressing in vivo bromine speciation in the brown algae Ectocarpus siliculosus, Ascophyllum nodosum, and Fucus serratus, the red algae Gracilaria dura, G. gracilis, Chondrus crispus, Osmundea pinnatifida, Asparagopsis armata, Polysiphonia elongata, and Corallina officinalis, the diatom Thalassiosira rotula, the dinoflagellate Lingulodinium polyedrum and a natural phytoplankton sample. The results highlight a diversity of fundamentally different bromine storage modes: while most of the stramenopile representatives and the dinoflagellate store mostly bromide, there is evidence for Br incorporated in nonaromatic hydrocarbons in Thalassiosira. Red algae operate various organic bromine stores – including a possible precursor (by the haloform reaction) for bromoform in Asparagopsis and aromatically bound Br in Polysiphonia and Corallina. Large fractions of the bromine in the red algae G. dura and C. crispus and the brown alga F. serratus are present as Br^? defects in solid KCl, similar to what was reported earlier for Laminaria parts. These results are discussed according to different defensive strategies that are used within algal taxa to cope with biotic or abiotic stresses.     

Water chemistry and algal vegetation of streams in the Asir Mountains,Saudi Arabia

Surveys of water chemistry and algal vegetation at nine stream sites in the Asir Mountains, Saudi Arabia, were made in March, 1984. The waters were moderately to highly calcareous with a relatively high Mg: Ca ratio and high concentrations of reactive-Si (x = 12.2 mg l^–1) and F (x = 0.73 mg l^–1). Ammonia typically constituted about one-sixth of the inorganic nitrogen. Filamentous algae (Cladophora and/or Spirogyra) were abundant at all but one site. However two sites, Wadi Habaqah and Al Tanoumah, differed considerably from the others in their overall floristic composition, with various species of Rivulariaceae, Nostoc verrucosum, Schizothrix lardacea and certain other blue-green algae present only here. With one minor exception, heterocystous blue-green algae were absent at the other sites. Tufa was deposited at these two sites, but not elsewhere. Species which appeared to play an active role in calcification included Dichothrix gypsophila, Calothrix parietina, Cladophora glomerata and the moss Bryum sp. A community apparently not previously recorded in the literature was abundant at Wadi Habaqah. This consisted of thick mats of Cladophora glomerata, with a thin surface layer of Zygnemales and numerous colonies of Nostoc verrucosum inside, or towards the underside, of the mat.     

Recent changes in the seaweed community of Western Prince Edward Island: implications for the seaweed industry

Prior to 1980, seaweed beds of western Prince Edward Island, Canada, were dominated by Chondrus crispus Stackhouse, associated with 37 other species of common algae. Furcellaria lumbricalis (Huds.) Lamour. occurred in 4.6% of the samples from the Pleasant View bed but never reached measurable levels of cover. By 1991 F. lumbricalis was reported in 67% of the samples from this bed. Furcellaria lumbricalis biomass was negatively correlated with C. crispus biomass and positively correlated with Phyllophora Grev. spp. biomass. F. lumbricalis biomass and cover peaked in subtidal areas below 4 m at 359 ± 299 SD fresh g 0.25 m^–2. Harvesters avoid concentrations of F. lumbricalis, resulting in a 5% content of this species in the commercial harvest. Systematic harvesting located concentrations of F. lumbricalis in seven of 10 commercial beds. Proposed causes for change in species dominance from C. crispus to F. lumbricalis range from general environmental change, natural succession to excessive human perturbation.     

ELECTROPHORETIC AND IMMUNOLOGICAL ANALYSES OF SEVEN CHLOROSARCINACEAN ALGAE1

Proteins from 7 species of chlorosarcinacean algae representing 4 genera were studied with starch and disc gel electrophoresis and immunology to determine biochemical relationships. Migration patterns of enzymes and serological reactions indicated that 4 species of Chlorosarcinopsis were closely related, whereas Friedmannia israeliensis, Fasciculochloris boldii, and Chlorosarcina longispinosa were more diverse. Malate dehydrogenase, glutamate dehydrogenase, nonspecific alpha esterases, and peroxidase (using pyrogallol as the hydrogen donor) were present in all 7 species. No peroxidase activity occurred with benzidine. Leucine aminopeptidase was obvious in only 2 species. A single distinct band of general protein in F. israeliensis and C. longispinosa suggested the presence of homogenous reserve protein. The 7 species exhibited serological affinity to 4 isolates of Protosiphon representing diverse morphology within the genus. The data are discussed relative to current knowledge of comparative morphology of chlorosarcinacean algae.     

Production of fucoid brown algae <Emphasis Type="Italic">Ascophyllum nodosum</Emphasis> and <Emphasis Type="Italic">Fucus vesiculosus</Emphasis> in the White Sea

Year-round studies of photosynthesis and respiration in the fucoid brown algae Ascophyllum nodosum and Fucus vesiculosus in the White Sea were performed. The annual specific production of the macrophytes was determined to be 1314 and 1642 cal/g of wet weight for A. nodosum and F. vesiculosus, respectively. The total annual production of fucoids (4.88 × 10¹¹ kcal) comprised about 0.8% of the phytoplankton production in the White Sea.