Microalgae
Dotaz
Zobrazit nápovědu
With the advent rise is in urbanization and industrialization, heavy metals (HMs) such as lead (Pb) and cadmium (Cd) contamination have increased considerably. It is among the most recalcitrant pollutants majorly affecting the biotic and abiotic components of the ecosystem like human well-being, animals, soil health, crop productivity, and diversity of prokaryotes (bacteria) and eukaryotes (plants, fungi, and algae). At higher concentrations, these metals are toxic for their growth and pose a significant environmental threat, necessitating innovative and sustainable remediation strategies. Bacteria exhibit diverse mechanisms to cope with HM exposure, including biosorption, chelation, and efflux mechanism, while fungi contribute through mycorrhizal associations and hyphal networks. Algae, especially microalgae, demonstrate effective biosorption and bioaccumulation capacities. Plants, as phytoremediators, hyperaccumulate metals, providing a nature-based approach for soil reclamation. Integration of these biological agents in combination presents opportunities for enhanced remediation efficiency. This comprehensive review aims to provide insights into joint action of prokaryotic and eukaryotic interactions in the management of HM stress in the environment.
- MeSH
- Bacteria * metabolismus účinky léků MeSH
- biodegradace * MeSH
- Eukaryota metabolismus účinky léků MeSH
- houby metabolismus MeSH
- kadmium * metabolismus toxicita MeSH
- látky znečišťující půdu * metabolismus MeSH
- olovo * metabolismus toxicita MeSH
- rostliny mikrobiologie metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Ultraviolet (UV) radiation is a significant environmental stressor that affects the growth, physiology, and biochemical integrity of various organisms. This study investigates the potential protective effects of a zinc-cysteine (Zn-Cys) complex against UV-C radiation, with a focus on its impact on selected microalgae (Coccomyxa peltigerae and Parachlorella kessleri) and maize (Zea mays L.). We demonstrate that exposure of the Zn-Cys complex to UV-C (254 nm) results in the formation of fluorescent photoproducts, which exhibit UV-protective properties. The study reveals that Zn-Cys significantly mitigates UV-induced stress. In both microalgae species, the Zn-Cys complex enhanced growth even under UV exposure, with the 20% concentration showing the most robust protective effects. Further hyperspectral imaging confirmed the protective mechanism of Zn-Cys by monitoring changes in light reflectance in Parachlorella kessleri, indicating reduced photosynthetic efficiency and structural alterations induced by UV exposure, while Zn-Cys significantly mitigated these effects. In addition, in maize plants (Zea mays L.), Zn-Cys treatment preserved chlorophyll content and reduced polyphenol accumulation, indicating reduced oxidative stress. These findings highlight the potential of the Zn-Cys complex as a sustainable and cost-effective strategy for UV protection in both terrestrial and extraterrestrial agriculture, advancing our understanding of plant adaptation to extreme environments.
- MeSH
- Chlorophyta účinky záření účinky léků MeSH
- cystein * chemie farmakologie MeSH
- fotosyntéza účinky léků účinky záření MeSH
- komplexní sloučeniny * chemie farmakologie MeSH
- kukuřice setá účinky záření účinky léků metabolismus MeSH
- mikrořasy účinky záření účinky léků MeSH
- ultrafialové záření * MeSH
- zinek * chemie farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
Agriculture is at the pivot point between anthroposphere, biosphere, and atmosphere. Innovative solutions are needed to reduce agricultural emissions and improve sustainability. Microalgae animal feed could be such a solution. This study aimed to evaluate the effects of 10 freshwater microalgae: Auxenochlorella protothecoides, Chlamydomonas pulvinate, Chlorella luteoviridis, Chlorella variabilis, Euglena mutabilis, Parachlorella kessleri, Stichococcus bacillaris, Tetradesmus acuminatus, Tetradesmus obliquus, and Tetraselmis gracilis, on ruminal methane (CH4) production, nutrient digestibility, and rumen fermentation using the in vitro Hohenheim gas test. The microalgae were cultured in a carbon dioxide (CO2) incubator at 2% CO2, at the optimal conditions for each strain. The highest producers were P. kessleri and T. obliquus, with a biomass concentration of 0.69 and 0.73 g/L·d, respectively. Their PUFA contents ranged from 33.2% to 69.1% of total fatty acids. Microalgae were tested at a 15% replacement in a control basal diet of 40.0% DM grass silage, 40.0% maize silage, 15% hay, and 5% concentrate. Data were analyzed using a mixed model in R. Ruminal CH4 production was reduced by 15.4%, 17.4%, and 16.4% in diets containing A. protothecoides, C. luteoviridis, and P. kessleri, respectively, compared with the control diet. Similarly, these diets reduced in vitro organic matter digestibility by 3.5%, 5.2%, and 5.4%, respectively. However, only A. protothecoides reduced CH4/CO2 ratio by 3.5% compared with the control diet. Propionate molar proportion was decreased by 2.4, 3.0, 2.5, and 2.5 percentage points for diets containing Ch. pulvinate, E. mutabilis, P. kessleri, and T. obliquus, respectively. Marginal effects of dietary variables were analyzed using the generalized additive model framework, revealing a negative relationship between dietary PUFA, sulfur content, and CH4 production, and a negative relationship between dietary PUFA and CH4/CO2 ratio. Incorporating high-PUFA microalgae in ruminant diets shows potential for reducing enteric CH4 emissions, warranting further investigation.
- MeSH
- bachor * metabolismus MeSH
- dieta veterinární MeSH
- fermentace MeSH
- krmivo pro zvířata MeSH
- methan * metabolismus MeSH
- mikrořasy * metabolismus MeSH
- siláž MeSH
- skot MeSH
- sladká voda MeSH
- trávení MeSH
- zvířata MeSH
- Check Tag
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Dictyosphaerium chlorelloides is a green microalga from the Chlorella clade that produces highly viscous exocellular polysaccharides. The cell wall polysaccharides of this alga have not been studied in detail. In this article, water-soluble polysaccharides from D. chlorelloides biomass were extracted with hot water and purified by preparative chromatography. The composition, structural features and molecular masses of subsequently eluted fractions F1, F2, F3, F4 and F5 (minor) were determined. Three high-yield products F1, F3 and F4 consisted mainly of galactopyranosyl, 2-O-methyl-galactopyranosyl, rhamnopyranosyl and mannopyranosyl units at different proportions, while F2 was rich in glucose. Immunoactivity of these fractions was evidenced in a mixed population of immune cells derived from mice spleens after incubation with polysaccharides by flow cytometry, MTT and Immunospot assays. These fractions, except F2, demonstrated selective immunostimulant activity, and the F1 fraction induced the most potent effect, closely followed by the F3 and F4 fractions. The in vivo mechanism of their action is associated with the activation of innate immunity and shapes the immune response to the Th1 type.
- MeSH
- adjuvancia imunologická farmakologie chemie izolace a purifikace MeSH
- buněčná stěna * chemie MeSH
- Chlorophyta chemie MeSH
- mikrořasy * chemie MeSH
- myši inbrední BALB C MeSH
- myši MeSH
- polysacharidy * farmakologie chemie izolace a purifikace MeSH
- slezina cytologie účinky léků MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
This review summarizes the available information about potential sources of vitamin B12, especially for people who follow a vegan or vegetarian diet and inhabitants of poor countries in the developing world. Cyanobacteria and microalgae approved for food purposes can play a critical role as promising and innovative sources of this vitamin. This work involves a discussion of whether the form of vitamin B12 extracted from microalgae/cyanobacteria is biologically available to humans, specifically focusing on the genera Arthrospira and Chlorella. It describes analyses of their biomass composition, cultivation requirements, and genetic properties in B12 production. Furthermore, this review discusses the function of cobalamin in microalgae and cyanobacteria themselves and the possibility of modification and cocultivation to increase the content of B12 in their biomass.
INTRODUCTION: Polyunsaturated fatty acids (PUFAs) are essential nutrients that humans obtain from their diet, primarily through fish oil consumption. However, fish oil production is no longer sustainable. An alternative approach is to produce PUFAs through marine microalgae. Despite the potential of algae strains to accumulate high concentrations of PUFAs, including essential fatty acids (EFAs), many aspects of PUFA production by microalgae remain unexplored and their current production outputs are frequently suboptimal. METHODS: In this study, we optimized biomass and selected ω-3 PUFAs production in two strains of algae, Schizochytrium marinum AN-4 and Schizochytrium limacinum CO3H. We examined a broad range of cultivation conditions, including pH, temperature, stirring intensity, nutrient concentrations, and their combinations. RESULTS: We found that both strains grew well at low pH levels (4.5), which could reduce bacterial contamination and facilitate the use of industrial waste products as substrate supplements. Intensive stirring was necessary for rapid biomass accumulation but caused cell disruption during lipid accumulation. Docosahexaenoic acid (DHA) yield was independent of cultivation temperature within a range of 28-34°C. We also achieved high cell densities (up to 9 g/L) and stable DHA production (average around 0.1 g/L/d) under diverse conditions and nutrient concentrations, with minimal nutrients required for stable production including standard sea salt, glucose or glycerol, and yeast extract. DISCUSSION: Our findings demonstrate the potential of Schizochytrium strains to boost industrial-scale PUFA production and make it more economically viable. Additionally, these results may pave the way for smaller-scale production of essential fatty acids in a domestic setting. The development of a new minimal culturing medium with reduced ionic strength and antibacterial pH could further enhance the feasibility of this approach.
- Publikační typ
- časopisecké články MeSH
Arthrospira (Limnospira) maxima (A. maxima) and Chlorella vulgaris (Ch. vulgaris) are among the approved microalgae and cyanobacteria (MaC) in the food industry that are known to be safe for consumption. However, both organisms are controversial regarding their vitamin B12 content, due to the possible occurrence of pseudo-cobalamin. Concurrently, their nutrition profiles remain understudied. The main purpose of the present study was to identify their nutrition profiles, focusing mainly on vitamin B12, amino acids, and micronutrients under iron-induced hormesis (10 mg/L Fe in treated samples). Our findings indicate a higher B12 content in A. maxima compared to Ch. vulgaris (both control and treated samples). Using liquid chromatography with tandem mass spectrometry (LC-MS/MS), the cyanocobalamin content was determined as 0.42 ± 0.09 μg/g dried weight (DW) in the A. maxima control and 0.55 ± 0.02 μg/g DW in treated A. maxima, resulting in an insignificant difference. In addition, the iron-enriched medium increased the amount of iron in both tested biomasses (p < 0.01). However, a more pronounced (approximately 100×) boost was observed in Ch. vulgaris, indicating a better absorption capacity (control Ch. vulgaris 0.16 ± 0.01 mg/g Fe, treated Ch. vulgaris 15.40 ± 0.34 mg/g Fe). Additionally, Ch. vulgaris also showed a higher micronutrient content. Using both tested microalgae, meeting the sufficient recommended daily mineral allowance for an adult is possible. By combining biomass from A. maxima and Ch. vulgaris in a ratio of 6:1, we can fulfill the recommended daily allowance of vitamin B12 and iron by consuming 6 tablets/6 g. Importantly, iron hormesis stimulated amino acid composition in both organisms. The profile of amino acids may suggest these biomasses as promising potential nutrition sources.
- MeSH
- aminokyseliny * metabolismus analýza MeSH
- Chlorella vulgaris * chemie metabolismus růst a vývoj MeSH
- mikrořasy chemie metabolismus růst a vývoj MeSH
- mikroživiny * analýza metabolismus MeSH
- nutriční hodnota MeSH
- Spirulina * chemie metabolismus MeSH
- tandemová hmotnostní spektrometrie MeSH
- vitamin B 12 * metabolismus analýza MeSH
- železo metabolismus analýza MeSH
- Publikační typ
- časopisecké články MeSH
Nitrogen is one of the most important nutrient sources for the growth of microalgae. We studied the effects of nitrogen starvation on the growth responses, biochemical composition, and fatty acid profile of Dunaliella tertiolecta, Phaeodactylum tricornutum, and Nannochloropsis oculata. The lack of nitrogen caused changes in carbohydrate, protein, lipid, and fatty acid composition in all examined microalgae. The carbohydrate content increased 59% in D. tertiolecta, while the lipid level increased 139% in P. tricornutum under nitrogen stress conditions compared to the control groups. Nitrogen starvation increased the oligosaccharide and polysaccharide contents of D. tertiolecta 4.1-fold and 3.6-fold, respectively. Furthermore, triacylglycerol (TAG) levels in N. oculata and P. tricornutum increased 2.3-fold and 7.4-fold, respectively. The dramatic increase in the amount of TAG is important for the use of these microalgae as raw materials in biodiesel. Nitrogen starvation increased the amounts of oligosaccharides and polysaccharides of D. tertiolecta, while increased eicosapentaenoic acid (EPA) in N. oculata and docosahexaenoic acid (DHA) content in P. tricornutum. The amount of polyunsaturated fatty acids (PUFAs), EPA, DHA, oligosaccharides, and polysaccharides in microalgal species can be increased without using the too costly nitrogen source in the culture conditions, which can reduce the most costly of living feeding.
In this review, research on the use of microalgae as an option for bioremediation purposes of pharmaceutical compounds is reported and discussed thoroughly. Pharmaceuticals have been detected in water bodies around the world, attracting attention towards the increasing potential risks to humans and aquatic biota. Unfortunately, pharmaceuticals have no regulatory standards for safe disposal in many countries. Despite the advances in new analytical techniques, the current wastewater treatment facilities in many countries are ineffective to remove the whole presence of pharmaceutical compounds and their metabolites. Though new methods are substantially effective, removal rates of drugs from wastewater make the cost-effectiveness ratio a not viable option. Therefore, the necessity for investigating and developing more adequate removal treatments with a higher efficiency rate and at a lower cost is mandatory. The present review highlights the algae-based removal strategies for bioremediation purposes, considering their pathway as well as the removal rate and efficiency of the microalgae species used in assays. We have critically reviewed both application of living and non-living microalgae biomass for bioremediation purposes considering the most commonly used microalgae species. In addition, the use of modified and immobilized microalgae biomass for the removal of pharmaceutical compounds from water was discussed. Furthermore, research considering various microalgal species and their potential use to detoxify organic and inorganic toxic compounds were well evaluated in the review. Further research is required to exploit the potential use of microalgae species as an option for the bioremediation of pharmaceuticals in water.
- MeSH
- biodegradace MeSH
- biomasa MeSH
- léčivé přípravky metabolismus MeSH
- lidé MeSH
- mikrořasy * metabolismus MeSH
- odpadní voda MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
