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PubMed1983

The quality of protein from algae used in the purification of wastewater from the nitrogen fertilizer industry.

This paper presents the quantities and amino acid composition of proteins from Chlorella vulgaris, Scenedesmus obliquus and Stichococcus bacillaris used in purification experiments on wastewater from the Nitrogen Fertilizer Factory in Chorzów. The quantities of exogenous amino acids of the investigated algae and "ideal protein" standard of the FAO are compared. The protein from Scenedesmus and Chlorella appeared to be richer in exogenous amino acids than the FAO standard. Stichococcus bacillaris has a lower content of exogenous amino acids but nevertheless has a high content of threonine and lysine, higher than in the other investigated algae.

Amino Acids↗
PubMed1978

Biokinetic aspects of tissue-bound tritium in algae.

For the estimate of the radiation exposure of man and for the calculation of the risk of artificial tritium from nuclear power plants, organic tissue-bound tritium is of decisive importance. In model experiments, a tritium incorporation of 61 to 71% was found from tritiated water (HTO) into organic matter of planctonic algae under under reproducible conditions and this was related to the theoretical value. In further experiments the tritium release from these high tritiated algae was of interest. Kept in darkness in tritium-free, non-sterile river water, so that autolytic processes and bacterial decomposition could occur, the concentration of HTO was measured over a period of three weeks. A relatively long half-life of tissue-bound tritium was found under various temperature conditions. Therefore it must be considered that a significant retention of tritium in biological matter has to be taken into account in a natural ecosystem. In streams into which the cooling water of a nuclear reactor is released all conditions are found already for a long turnover and cycling of artificial tritium in living organisms as well as the conditions for a favourable transport of tritium by food chains to man.

Ecology↗
PubMed1980

[New approach to the study of the experimental inhibitory effect of the unicellular alga Chlorella pyrenoidosa against the murine sarcomas BP8 and L1210].

In this paper, the authors are relating the inhibitory effect of the unicellular alga Chlorella (Beijerinck, 1890) pyrenoidosa Zeitler and Lund, against the tumoural rodent strains BP8 and L1210, according to the amount of inoculum. The statistical study of the results allows to the conclusive fact of a real protective effect showed by this microorganism and of a demonstrative relation between the amount of the protective material and the tumoural answers the high amount giving a better inhibitory effect. The workers also insist on the lack of pathogenicity presented by the alga used in this study.

Animals↗
PubMed1982

[In vitro repair of gamma-irradiated transforming Bacillus subtilis DNA by extracts of blue-green algae].

A cell-free extract from blue-green alga Anacystis nidulans contains enzymes which repair in vitro the transforming activity of gamma-irradiated Bacillus subtilis DNA. The level of restoration of the transforming activity depends on the protein concentration in the reaction mixture, the duration of incubation and on the dose of irradiation. The repair of gamma-induced lesions is most efficient in the presence of magnesium ions, NAD and ATP. The present data indicate that the repair of transforming DNA is performed with the participation of DNA polymerase and polynucleotide ligase which function in the cell-free extract of algae.

Bacillus subtilis↗
PubMed1981

Gibberellin- and cytokinin-like activities in marine algae from central Mediterranean.

The distribution of gibberellin- and cytokinin-like activities in twenty-one species of mediterranean algae belonging to Phaeophyta and Rhodophyta has been investigated. Fractions containing each of these activities have been obtained by partitioning aqueous-methanolic extracts of algae against ethyl acetate and butanol successively at different pH values. The stimulation or inhibition of amaranthin synthesis in Amaranthus sp. seedlings have been used a biological tests to assay the cytokinin- or gibberellin-like activities respectively. One or both these two hormonal activities have been detected in all species examined. While cytokinin-like activity has been found with the same frequency in the two phyla, the gibberellin-like activity was less frequent in Phaeophyta.

Biological Assay↗
PubMed1981

An electron microscopic study on tetrasporogenesis of the parasitic red alga Erythrocystis Montagnei (Derb. and Sol.) Silva.

An ultrastructural study has been carried out on the cells involved in the formation and ripening of tetraspores in the red alga Erythrocystis Montagnei. This organism is considered a parasitic species, although relationships with the host plant are not completely known. The work reveals a series of morphological changes in dictyosomes, which assume different dispositions of cisternae and produce different kinds of vesicles in the various stages of tetrasporogenesis. Plastids reach their complete differentiation when the cleavage furrows are nearly complete. Their complexity is comparable to that visible in autotrophic red algae. It is confirmed that during tetrasporogenesis the cytological changes are less profound than those which take place in the course of carposporogenesis.

Cell Differentiation↗
PubMed1978

The fine structure of the vegetative cells of Erythrocystis montagnei, a symbiotic red alga.

Erythrocystis montagnei lives as a symbiont on the thallus of another red alga, Laurencia paniculata. This electron microscope study carried out on its vegatative cells shows that the plastids have a fine structure adequate to perform photosynthesis, different from that observed in other parasitic red algae. Starch granules occur frequently in all the cells of the thallus except the large vacuolized basal cell, which joins together the symbionts. These features suggest that Erythrocystis lives on its host plant for reasons other than a lack of photosynthesis.

Cytoplasmic Granules↗
PubMed1995

Cytokinesis by a contractile ring in the primitive red alga Cyanidium caldarium RK-1.

To better understand the mechanism of cytokinesis in eukaryotes, the behavior of the contractile ring in the two unicellular primitive red algae Cyanidioschyzon merolae and Cyanidium caldarium RK-1, which have the smallest genome size among eukaryotes, was examined by fluorescein isothiocyanate (FITC)-phalloidin fluorescence microscopy, fluorometry using a video-intensified microscope photoncounting system, transmission electron microscopy and immunoblotting techniques. Cells in each alga contained one nucleus, one mitochondrion and one chloroplast, which were aligned in that order. During cytokinesis in C. merolae, a contractile ring was not observed by fluorescence microscopy or by transmission electron microscopy. In contrast, in C. caldarium RK-1, a contractile ring appeared at the equatorial region of the dividing cells and began to contract from the side of the chloroplast. During contraction of this ring, the total fluorescent intensities due to FITC-phalloidin remained constant. Electron microscopy revealed outer and inner bands approximately 80 nm wide and 9 nm thick which ran parallel to each other just beneath the cell membrane. These bands were visible at the equator of the cell just before the initiation of cytokinesis and constricted from the pole of the chloroplast. Both bands increased in width as cleavage progressed. The inner ring consisted of a bundle of approximately 20 actin-like filaments which were arranged as a raft. In the outer ring, such fine filaments were not visible. It seems likely that the bundle of filaments, known as the contractile ring, is composed of two different elements: an inner band of actin filaments and an outer band of unknown materials.(ABSTRACT TRUNCATED AT 250 WORDS)

Actin Cytoskeleton↗
PubMed1993

[Preventive and metaphylactic use of Alga and Algalev in diarrheal and respiratory syndromes].

Two gammaglobulin preparations have been developed: Alga (10% injection solution of serum bovine gamma-globulin and albumin) and Algalev (with addition of levamisole 10 mg/ml, patented under PV 4069/87); their administration to calves in field conditions was evaluated. The Alga preparation at a rate of 1 ml/kg liveweight (two administrations) had good preventive effects in the diarrhoeic syndrome of new-born hypogammaglobulinaemic calves. In comparison with the untreated calves, these parameters were determined: lower incidence of diarrhoea (41% against 75%; Tab. I), its later onset (by 24 hours), shorter duration (by 50 hours; P < 0.01), lower intensity and easier therapeutical handling (Tab. II). The Algalev preparation (two administrations at a rate of 1 ml/kg liveweight) was suitable for metaphylactic use (combined with antibiotic application) in the respiration syndrome of calves. In comparison with the untreated calves, these parameters were determined: lower incidence of this disorder (42% against 78%), lower intensity of clinical symptoms (intensive symptoms in 20% of the calves against 72%) and importantly higher daily weight gains (0.64 kg against 0.26 kg; Fig. 3). The concentrations of total serum Ig (CS-Ig), serum proteins (SB) and serum albumin (S-Alb) were similar in the compared groups of calves in the whole period of observation (Fig. 1). Certain differences were observed in the dynamics of anti-PI 3 titre of serum antibodies as shown by investigation of specific serum antibodies (Fig. 2); the level of their production was in agreement with morbidity incidence and clinical symptom intensity in both groups of calves.

Animals↗
PubMed1994

[Metal concentrations in benthic marine algae in 3 regions of the state of Rio de Janeiro].

The concentrations of zinc, cadmium and copper were determined in different benthic algal species from some sites located in Guanabara Bay, Sepetiba Bay and Ribeira Bay (State of Rio de Janeiro). The aim is to verify the possibility of using algae as indicators of metallic contamination in these areas. According to our results, the highest concentrations of Zn and Cd in algae were observed in Sepetiba Bay. In this region, the differences among the concentrations of the metals were analysed in three sampling sites. Padina gymnospora was the species recommended to monitor the contamination of Zn and Cd in Sepetiba Bay, for the following reasons: 1) its great abundance and distribution in the areas, and 2) its high ability to accumulate metals. More studies are suggested to evaluate the levels of metals in Guanabara Bay.

Brazil↗
PubMed1994

Identification of mitochondrial respiratory proteins from the green alga Chlamydomonas reinhardtii.

Membrane preparations from the green alga Chlamydomonas reinhardtii contain both thylakoid and mitochondrial membranes [1]. These preparations have been intensely used to study the structure, function and biogenesis of protein complexes involved in the photosynthetic pathway. We show here that these preparations are also suitable for studying protein complexes of the mitochondrial respiratory chain of the alga. The respiratory complexes, fractionated on a sucrose gradient in the presence of Triton X-100, were identified by their catalytic properties and their polypeptide content. From the bottom to the top of the sucrose gradient, we identified the NADH: ubiquinone oxidoreductase (complex I), the mitochondrial ATP synthase (F0F1-ATPase), the cytochrome bc1 complex and the cytochrome c oxidase. At the top of the gradient, another enzyme was detected which displayed an NADH: menaquinone oxidoreductase activity.

Amino Acid Sequence↗
PubMed1993

Core substructure of the hemiellipsoidal phycobilisome from the red alga Porphyridium cruentum.

The allophycocyanin core of hemiellipsoidal phycobilisomes from the red alga, Porphyridium cruentum, was isolated by chromatography on hydroxylapatite and subsequent density gradient centrifugation. Electron microscopy of negatively stained core complexes revealed a tricylindrical structure with a width of 21 to 23 nm in face view and a depth of 12 to 14 nm in side view. Fluorescence emission spectra of these complexes were similar to those of whole phycobilisomes confirming the presence of the two "terminal energy acceptors" allophycocyanin B (APB) and the high molecular linker polypeptide LCM. The polypeptide composition analyzed by SDS-PAGE showed the "anchor" polypeptide LCM, alpha AP, alpha APB, beta AP subunits, a low molecular weight linker with M(r) 13,500 and a blue-colored polypeptide of M(r) 19,800. A complex containing APB could be isolated from a "trimeric" allophycocyanin fraction of the density gradient by agarose gel electrophoresis in the presence of ampholytes. This complex shows a polypeptide composition of (alpha APB alpha AP2 beta AP3).L13.5C and contributes to the core with 30 to 35% of total "trimers". In comparison to the allophycocyanin cores from hemidiscoidal phycobilisomes of cyanobacteria and red algae, all data concerning the core of the hemiellipsoidal phycobilisomes from Porphyridium cruentum strongly suggest that there is no increase in size but an increase in its APB content. A model comprising the allophycocyanin core and the membrane integral photosystem II particles presents the structural and possible functional consequences of the results.

Bacterial Proteins↗
PubMed1976

[Ribosomes of the blue-green alga Anabaena variabilis. Sedimentation, density characteristics and analysis of ribosomal RNA].

Ribosomes and rRNAs were isolated from cells of green-blue alga Anabaena variabilis. The sedimentation properties of the ribosomes as well as density, molecular weights and nucleotide composition of rRNAs were determined. The ribosomes were found to have the S20,w value equal to 67.2+/-0.4S, whereas those of the ribosome subunits were 48.6+/-0.8 and 29.5+/-1.1S. The buoyant density of the ribosomes in CsCl was 1.641+/-+/-0.002 g/cm3; a calculated relative protein content was 35%. The molecular weights of rRNAs estimated by electrophoresis in PAAG containing 0.5% agarose, are 1.1-10(-6) and 0.56-10(6) daltons. The nucleotide composition of rRNA was determined and rRNA was shown to belong to the GC type. Consequently, the blue-green alga ribosomes do not differ in the parameters studied from bacterial ribosomes.

Centrifugation, Density Gradient↗
PubMed1975

[Production and characteristic constituents of the algae Spirulina platensis and maxima].

Microscopic blue-green Spirulina algae, such as have been consumed since ancient times, are algae having a very high protein content (70 p. 100 of dry matter). At present the Spirulina platensis species in the Kanem region in Chad is gathered by primitive methods, sold in the marketplace and consumed by the local population. The Spirulina maxima species exists in a seminatural state in Mexico City, and an industrial pilot plant harvests and produces one ton per day. Both species, Sp. platensis and maxima, can be cultivated in the same way in a controlled synthetic medium in large-area basins. Whether these Spirulina come from a natural medium or synthetic culture basin, harvesting includes the successive stages of concentration, filtration and washing followed by drying done in a conventional manner. The characteristic constituents of Spirulina platensis and Spirulina maxima, in addition to the high protein content, are both nucleic acids that account for about 4 p. 100 of the dry matter and the fatty-acid composition which is saturated C16 and ethylenic C18 substances. Linoleic acid and especially gamma-linolenic acid arecharacteristic of these two species. The unsaponifiable content is made up in particular of sterols such as cholesterol and beta-sitosterol as well as by triterpenic alcohols such as alpha-amyrin.

Amino Acids↗
PubMed1975

[Consumption and nutritional contribution of the blue algae (Oscillatoria platensis) among some populations of Kanem (Tchad)].

Two food surveys determined the areas of consumption and the ethnic groups involved as well as the way and motivations for using Spirulina algae (Oscillatoria platensis) in Chad. More than 400 homes were visited in February (dry season) and October (end of the rainy season and period after the millet harvest). Consumption is limited to a restricted proportion of the population in the Kanem region. Among the Kanembu group (the leading consumers of Spirulina), frequencies of use vary between one and six melas out of ten. The amounts consumed per person during a meal, in the sauce accompanying millet, are between 9 and 13 g. Variations in consumption linked to ethnic, social and seasonal factors are discussed. With regard to food value, the very high proportion of sand considerably reduces the protein content in the product sold on the market. An average ration of sauce containing "diĕ" helps cover about 10 to 12 p. 100 of the protein requirements of an active adult man, and the algae by themselves contribute 5 to 8 p. 100 of these requirements. A comparison with the leading sauces consumed in Kanem reveals no superiority for Spirulina.

Adult↗
PubMed1975

[Food value of the spiruline algae to man].

The acceptability of various culinary products based on the algae spirulina was tested by questionaire: formulas rich in proteins, soups, omelets, desserts. Spirulina are little appreciated in France due to offensive color, smell and taste. Tomato and chocolate are the most acceptable flavors. Lyophilisation is preferable to atomisation, and discoloration using alcohol is preferable to the acetone method. The hydrolysate obtained, having neither the smell nor the taste of algae, is excellent. Nitrogen, sodium and potassium balances were recorded in 5 undernourished subjects fed via a gastric tube. The spirulina provided respectively 15 p. 100 (1 subject), 30 p. 100 (2 subjects), and 50 p. 100 (2 subjects) of the protein ration. There were no intestinal problems. The spirulina did not modify the investigated balances. However, faecal nitrogen increased to 2.08 g (compared to control period values, 1.33 g and 1.51 g). The various coefficients: digestibility, nitrogen retention and protein utilization did not vary. In man as in animals, nitrogen retention is satisfactory, but digestibility is diminished. Uric acid did not vary in the urine, but serum values increased slightly. Ingestion of spirulina in small doses even over a long period should be tolerable in the normal subject.

Animals↗
PubMed1975

[Determination of 3, 4-benzopyrene in spiruline algae produced and treated by various procedures].

Spirulina algae grow in highly salted natural lakes. Artificial cultivation in tanks with addition of carbon dioxide (natural gas, burned gases) has been studied in order to improve the biosynthesis. A possible 3, 4-benzopyrene (BaP) contamination must be then considered. Several BaP determinations have been performed in batches of algae from bath origins, prepared following different processes (filtration, spray, cylinder drying). BaP contents are very low (2 to 3 ppb) and comparable between batches.

Benzopyrenes↗
PubMedDate not supplied

[Photodestruction of the blue-green alga Anabaena variablis].

The effect of light on the cells was studied with the obligate phototrophic blue-green alga Anabaena variabilis after its incubation in the dark. Incubation of the alga in the dark during two weeks was not essential for the cell reproduction systems in the light. Incubation in the dark during 3-4 weeks caused damages in the systems which were however reversible and repaired in the light. Longer incubation of the cells in the dark results in irreversible damages of the systems protecting them from photooxidation which may be the main factor preventing growth of the cells in the light.

Carotenoids↗