microalga Dotaz Zobrazit nápovědu
The aim of the study was to identify the optimum cultivation conditions for the microalgal growth and lipid production of the oleaginous microalga Chlorella pyrenoidosa Chick (IPPAS C2). Moreover, an appropriate NO3- concentration in the cultivation medium for maximized lipid accumulation was determined. The experimental design involved a biphasic cultivation strategy with an initial biomass accumulating phase under optimized light (400 μmol/m2 per s), temperature (25 °C), and elevated CO2 concentration in the air mixture (3%), followed by a mid-elevated CO2 concentration (0.5%) for lipid induction. The highest lipid yields of 172.47 ± 18.1 and 179.65 ± 25.4 mg/L per day were detected for NO3- concentrations of 100 and 150 mg/L. The optimization approach presented here led not only to the maximization of lipid yield but also to the development of a biphasic cultivation strategy easily applicable to the cultivation process without the necessity for algal cell harvesting between the first and second cultivation phases.
- MeSH
- biomasa MeSH
- Chlorella růst a vývoj metabolismus MeSH
- dusičnany metabolismus MeSH
- fotobioreaktory MeSH
- kultivační média metabolismus MeSH
- lipidy biosyntéza MeSH
- mikrořasy růst a vývoj metabolismus MeSH
- oxid uhličitý metabolismus MeSH
- techniky vsádkové kultivace MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
The objective of the present study was to evaluate a potential of Schizochytrium microalga oil to alleviate possible negative effects of high-fat-high-energy diets. Forty adult male rats (Wistar Albino) were fed 7 weeks the diet containing beef tallow + evaporated sweetened milk (diet T) intended to cause mild obesity and low-grade systemic inflammation. Consequently, the animals were divided into four groups by 10 animals each and fed either the T-diet (control) or the diet containing 6% of safflower oil (S), 6% of fish oil (F) and 6% of Schizochytrium microalga oil (A), respectively, for another 7 weeks. The A-diet decreased (p < 0.05) live weight to 86% and glycaemia to 85% of control, respectively; an effect of the S- and F-diet on these markers was insignificant (p > 0.05). In comparison with control, higher (p < 0.05) deposition of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) in the epididymal adipose tissue (EAT) of the A-rats correlated with increased (p < 0.05) plasma adiponectin concentration, but it was without the effect (p > 0.05) on cellular adiponectin content in the EAT. Higher (p < 0.05) EPA+DHA deposition in the liver of the A-rats correlated with higher expression (149% of control; p < 0.05) of the gene coding for peroxisome proliferator-activated receptor gamma, and with lower expression (82% and 66%; p < 0.05) of the genes coding for adiponectin receptors AdipoR1 and AdipoR2; no relationship to the expression of receptor GPR120 was found. The A-diet did not affect amount of the nuclear fraction of the nuclear factor kappa B in the liver, but increased plasma level of anti-inflammatory cytokine TGF-β1 (p < 0.05). The presented data agree with results of other in vivo rodent and human studies, but not with literature data regarding in vitro experiments: it can be concluded that the effects of dietary oils on inflammatory markers need further investigation.
- MeSH
- adiponektin genetika metabolismus MeSH
- cytokiny genetika metabolismus MeSH
- dieta veterinární MeSH
- krmivo pro zvířata analýza MeSH
- krysa rodu rattus MeSH
- mikrořasy chemie MeSH
- náhodné rozdělení MeSH
- NF-kappa B genetika metabolismus MeSH
- oleje rostlin chemie farmakologie MeSH
- potkani Wistar MeSH
- PPAR gama genetika metabolismus MeSH
- regulace genové exprese účinky léků MeSH
- zánět farmakoterapie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
A terrestrial green microalga was isolated at Ås, in Akershus County, Norway. The strain corresponded to a coccoid chlorophyte. Morphological characteristics by light and electron microscopy, in conjunction with DNA amplification and sequencing of the 18 s rDNA gene and ITS sequences, were used to identify the microalgae. The characteristics agree with those of the genus Coelastrella defined by Chodat, and formed a sister group with the recently described C. thermophila var. globulina. Coelastrella is a relatively small numbered genus that has not been observed in continental Norway before; there are no previous cultures available in collections of Norwegian strains. Gas chromatography analyses of the FAME-derivatives showed a high percentage of polyunsaturated fatty acids (44-45%) especially linolenic acid (C18:3n3; 30-34%). After the stationary phase, the cultures were able to accumulate several carotenoids as neoxanthin, pheophytin a, astaxanthin, canthaxanthin, lutein, and violaxanthin. Due to the scarcity of visual characters suitable for diagnostic purposes and the lack of DNA sequence information, there is a high possibility that species of this genus have been neglected in local environmental studies, even though it showed interesting properties for algal biotechnology.
- MeSH
- biologické pigmenty analýza MeSH
- biotechnologie MeSH
- Chlorophyta klasifikace cytologie genetika MeSH
- druhová specificita MeSH
- feofytiny analýza MeSH
- fylogeneze * MeSH
- karotenoidy analýza MeSH
- kyselina alfa-linolenová analýza MeSH
- mastné kyseliny analýza MeSH
- mikrořasy klasifikace cytologie genetika izolace a purifikace MeSH
- ribozomální DNA MeSH
- RNA ribozomální 18S genetika MeSH
- xanthofyly MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Norsko MeSH
The alga Parachlorella kessleri, strain CCALA 255, grown under optimal conditions, is characterized by storage of energy in the form of starch rather than lipids. If grown in the complete medium, the cultures grew rapidly, producing large amounts of biomass in a relatively short time. The cells, however, contained negligible lipid reserves (1-10% of DW). Treatments inducing hyperproduction of storage lipids in P. kessleri biomass were described. The cultures were grown in the absence or fivefold decreased concentration of either nitrogen or phosphorus or sulfur. Limitation by all elements using fivefold or 10-fold diluted mineral medium was also tested. Limitation with any macroelement (nitrogen, sulfur, or phosphorus) led to an increase in the amount of lipids; nitrogen limitation was the most effective. Diluted nutrient media (5- or 10-fold) were identified as the best method to stimulate lipid overproduction (60% of DW). The strategy for lipid overproduction consists of the fast growth of P. kessleri culture grown in the complete medium to produce sufficient biomass (DW more than 10 g/L) followed by the dilution of nutrient medium to stop growth and cell division by limitation of all elements, leading to induction of lipid production and accumulation up to 60% DW. Cultivation conditions necessary for maximizing lipid content in P. kessleri biomass generated in a scale-up solar open thin-layer photobioreactor were described.
- MeSH
- biomasa MeSH
- biotechnologie MeSH
- chlorofyl analýza metabolismus MeSH
- Chlorophyta metabolismus MeSH
- fotobioreaktory MeSH
- kultivační média MeSH
- lipidy biosyntéza MeSH
- mastné kyseliny analýza metabolismus MeSH
- metabolismus lipidů MeSH
- mikrořasy metabolismus MeSH
- oxid uhličitý metabolismus MeSH
- škrob analýza metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
The purpose of the study was to test the hypothesis that the dietary oils with different content of n-3 polyunsaturated fatty acids (PUFA) eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) affect plasma lipid level in rats in a different degree. The diets with 6% of fish oil (FO) and Schizochytrium microalga oil (SchO; EPA+DHA content in the diets 9.5 + 12.3 and 2.6 + 29.5% of the sum of total fatty acids, respectively) were used; the diet with 6% of safflower oil (high content of n-6 PUFA linoleic acid, 65.5%; EPA+DHA content 0.7 + 0.9%) was used as a control. The difference between FO and SchO was established only in the case of plasma triacylglycerol (TAG) level: plasma TAG of the FO-fed rats did not differ from the control rats (p > 0.05), while SchO decreased (p < 0.05) plasma TAG to 46% of the control. On the other hand, FO and SchO decreased (p < 0.05) total plasma cholesterol (TC) in rats in the same extent, to 73% of the control. Regarding the underlying mechanisms for the TC decrease, both SchO and FO up-regulated hepatic Insig-1 gene (181 and 133% of the control; p < 0.05), which tended (p = 0.15 and p = 0.19 respectively) to decrease the amount of hepatic nSREBP-2 protein (61 and 66% of the control). However, neither SchO nor FO influenced hepatic 3-hydroxy-3-methyl-glutaryl-CoA reductase gene expression (p > 0.05); SchO (but not FO) increased (p < 0.05) low-density lipoprotein receptor mRNA in the liver. It was concluded that the decrease of total plasma cholesterol might be caused by an increased cholesterol uptake from plasma into the cells (in the case of SchO), but also by other (in the present study not tested) mechanisms.
- MeSH
- cholesterol krev MeSH
- dieta MeSH
- játra chemie metabolismus MeSH
- krmivo pro zvířata analýza MeSH
- krysa rodu rattus MeSH
- mikrořasy chemie MeSH
- náhodné rozdělení MeSH
- nenasycené mastné kyseliny chemie metabolismus MeSH
- oleje rostlin chemie farmakologie MeSH
- potkani Wistar MeSH
- protein SREBP2 genetika metabolismus MeSH
- regulace genové exprese účinky léků MeSH
- rybí oleje chemie farmakologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This work has analysed the influence of CdCl2, NiCl2 and CuCl2 on simple phenolic acids, such as the 3PPP (phenylpyruvic, phenylacetic, and 4-hydroxyphenylpyruvic) and 2DR (3,4-dihydroxyphenylacetic and rosmarinic) phenolic acids for the first time and studied their interactions with antioxidant systems and the glutathione-ascorbate cycle in the freshwater green microalga Scenedesmus quadricauda. The compounds investigated are related to both the catabolic and anabolic pathways of l-phenylalanine and l-tyrosine, the main molecules in the biosynthesis of polyphenols. The concentrations of the simple phenolic acids responded significantly to NiCl2, CdCl2 and CuCl2 at 5, 20 and 40 μM concentrations. The 3PPP phenolic acid concentrations after 24 h were always higher in metal-treated cells than in controls, while the 2DR concentrations were significantly lower in the metal-treated cells than the controls. The GSH/GSSG ratio was lower in all experimental groups treated with the selected metals (especially so at 40 μM). Pearson correlation analysis indicated a strong negative correlation between ascorbate and rosmarinic acid content (-0.670; p < 0.05) in NiCl2-treated samples and reduced glutathione and 3,4-dihydroxyphenylacetic content (-0.700; p < 0.05) in CdCl2-treated samples. The GSSG content in samples exposed to CuCl2 was correlated with the concentrations of all of the investigated phenolic acids (4 negative, 1 positive).
- MeSH
- antioxidancia metabolismus MeSH
- chlorid kademnatý toxicita MeSH
- fytochelatiny metabolismus MeSH
- glutathion metabolismus MeSH
- hydroxybenzoáty metabolismus MeSH
- kyselina askorbová metabolismus MeSH
- měď toxicita MeSH
- mikrořasy účinky léků růst a vývoj metabolismus MeSH
- nikl toxicita MeSH
- oxidační stres účinky léků MeSH
- polyfenoly metabolismus MeSH
- Scenedesmus účinky léků růst a vývoj metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
Hot water extract from biomass of heterotrophic mutant green alga Parachlorella kessleri HY1 (Chlorellaceae) was deproteinised, and three polysaccharidic fractions were obtained by preparative chromatography. The low-molecular fraction (1.5 × 104g mol-1) was defined mainly as branched O-2-β-xylo-(1→3)-β-galactofuranan where xylose is partially methylated at O-4. Two high-molecular fractions (3.05 × 105 and 9.84 × 104g mol-1) were complex polysaccharides containing α-l-rhamnan and xylogalactofuranan parts in different ratios. The polysaccharides were well soluble in hot water and, upon cooling, tended to self-segregate. Immunomodulatory activities of the obtained fractions were preliminary tested using ELISA, FACS and ImmunoSpot kits. The polysaccharides increased the TNF-α production in melanoma bearing mice with much higher intensity than in healthy mice. This was in agreement with the FACS results on T and B cells indicating their possibly secondary activation by innate immunity cells.
- MeSH
- B-lymfocyty účinky léků imunologie patologie MeSH
- CD antigeny genetika imunologie MeSH
- Chlorophyta chemie MeSH
- imunologické faktory chemie izolace a purifikace farmakologie MeSH
- interferon gama genetika imunologie MeSH
- interleukin-2 genetika imunologie MeSH
- interleukin-4 genetika imunologie MeSH
- lipopolysacharidy antagonisté a inhibitory farmakologie MeSH
- melanom imunologie patologie MeSH
- metylace MeSH
- molekulová hmotnost MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- nádory kůže imunologie patologie MeSH
- polysacharidy chemie izolace a purifikace farmakologie MeSH
- primární buněčná kultura MeSH
- regulace genové exprese účinky léků MeSH
- rostlinné extrakty chemie MeSH
- rozpustnost MeSH
- sacharidové sekvence MeSH
- T-lymfocyty účinky léků imunologie patologie MeSH
- TNF-alfa genetika imunologie MeSH
- voda MeSH
- xylosa chemie izolace a purifikace MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The microalgae of the genus Asterochloris are the preferential phycobionts in Cladonia, Lepraria and Stereocaulon lichens. Recent studies have highlighted the hidden diversity of the genus, even though phycobionts hosting species of the genus Cladonia in Mediterranean and Canarian ecosystems have been poorly explored. Phylogenetic analyses were made by concatenation of the sequences obtained with a plastid - LSU rDNA - and two nuclear - internal transcribed spacer (ITS) rDNA and actin - molecular markers of the phycobionts living in several populations of the Cladonia convoluta-Cladonia foliacea complex, Cladonia rangiformis and Cladonia cervicornis s. str. widely distributed in these areas in a great variety of substrata and habitats. A new strongly supported clade was obtained in relation to the previously published Asterochloris phylogenies. Minimum genetic variation was detected between our haplotypes and other sequences available in the GenBank database. The correct identification of the fungal partners was corroborated by the ITS rDNA barcode. In this study we provide a detailed characterization comprising chloroplast morphology, and ultrastructural and phylogenetic analyses of a novel phycobiont species, here described as Asterochloris mediterranea sp. nov. Barreno, Chiva, Moya et Škaloud. A cryopreserved holotype specimen has been deposited in the Culture Collection of Algae of Charles University in Prague, Czech Republic (CAUP) as CAUP H 1015. We suggest the use of a combination of several nuclear and plastid molecular markers, as well as ultrastructural (transmission electron and confocal microscopy) techniques, both in culture and in the symbiotic state, to improve novel species delimitation of phycobionts in lichens.
- MeSH
- Ascomycota MeSH
- Chlorophyta klasifikace genetika ultrastruktura MeSH
- DNA rostlinná genetika MeSH
- fylogeneze * MeSH
- genetická variace MeSH
- konformace nukleové kyseliny MeSH
- lišejníky * MeSH
- mezerníky ribozomální DNA genetika MeSH
- molekulární sekvence - údaje MeSH
- sekvenční analýza DNA MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Španělsko MeSH
- Středomoří MeSH
Total lipid contents of green (Chlorella pyrenoidosa, C), red (Porphyra tenera, N; Palmaria palmata, D), and brown (Laminaria japonica, K; Eisenia bicyclis, A; Undaria pinnatifida, W, WI; Hizikia fusiformis, H) commercial edible algal and cyanobacterial (Spirulina platensis, S) products, and autotrophically cultivated samples of the green microalga Chlorella kessleri (CK) and the cyanobacterium Spirulina platensis (SP) were determined using a solvent mixture of methanol/chloroform/water (1:2:1, v/v/v, solvent I) and n-hexane (solvent II). Total lipid contents ranged from 0.64% (II) to 18.02% (I) by dry weight and the highest total lipid content was observed in the autotrophically cultivated cyanobacterium Spirulina platensis. Solvent mixture I was found to be more effective than solvent II. Fatty acids were determined by gas chromatography of their methyl esters (% of total FAMEs). Generally, the predominant fatty acids (all results for extractions with solvent mixture I) were saturated palmitic acid (C16:0; 24.64%-65.49%), monounsaturated oleic acid (C18:1(n-9); 2.79%-26.45%), polyunsaturated linoleic acid (C18:2(n-6); 0.71%-36.38%), α-linolenic acid (C18:3(n-3); 0.00%-21.29%), γ-linolenic acid (C18:3(n-6); 1.94%-17.36%), and arachidonic acid (C20:4(n-6); 0.00%-15.37%). The highest content of ω-3 fatty acids (21.29%) was determined in Chlorella pyrenoidosa using solvent I, while conversely, the highest content of ω-6 fatty acids (41.42%) was observed in Chlorella kessleri using the same solvent.
- MeSH
- analýza potravin MeSH
- Chlorophyta chemie MeSH
- kyselina alfa-linolenová chemie MeSH
- kyselina linolová chemie MeSH
- kyselina palmitová chemie MeSH
- kyseliny mastné omega-3 chemie MeSH
- lipidy chemie izolace a purifikace MeSH
- mořské řasy chemie MeSH
- rozpouštědla chemie MeSH
- sinice chemie MeSH
- sladká voda MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
V současné době je celosvětově vynakládáno velké úsilí na nahrazení fosilních zdrojů energie obnovitelnými zdroji (biomasa, slunce, vítr atd.), které by navíc nezatěžovali zemskou atmosféru produkcí skleníkových plynů. Ukazuje se, že nelze očekávat příchod jedné univerzální technologie, ale je nutné využívat mnoho různých zdrojů tak, aby byla zohledněna geografická a ekonomická specifika konkrétní oblasti, kde se energie vyrábí. Jedním z možných zdrojů energie je produkce bioplynu z biomasy řas pěstovaných za tímto účelem ve speciálních reaktorech. Tento článek dává stručný přehled metod energetického využívání řas a zmiňuje hlavní ekonomické a technologické výzvy pro úspěšné zvládnutí této technologie. Zároveň je zmíněn evropský projekt „Renewable energy production through microalgae cultivation: Closing material cycles (ALGAENET)“, který spojuje výzkumná pracoviště v České republice (VŠCHT Praha), Španělsku a Chile.
Recently, a great eÍort is being put on the development of new technologies allowing energy production from renewable source that would not produce greenhouse gases. It is becoming increasingly apparent that one should not expect the advent of a new universal technology that would replace the entire energy production from fossil fuels. Instead, we need to develop many diÍerent technologies that would satisfy wide range of geographical and economical requirements. Biogas production from microalgae may become such a site-specific technology. This paper gives a brief list of diÍerent approaches to energy production from microalgae and describes the main economic and technological challenges for biogas production from microalgae. Moreover, an European project “Renewable energy production through microalgae cultivation: Closing material cycles (ALGAENET)“ that is currently being jointly executed by partners in the Czech Republic (ICT Prague), Spain and Chile.
