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1.
Chemosphere ; 238: 124576, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31421462

RESUMO

This study assesses and compares the influence of silver nanoparticles (AgNPs) and silver nitrate (AgNO3) on the fatty acid composition, pigments, and growth indices of Chlorella vulgaris. Toxicity testing was carried at the estimated and/or above predicted environmental concentrations of AgNPs and AgNO3. AgNO3 treatments impaired the population growth of C. vulgaris about 2-183 times more than the respective AgNPs ones. The pigments displayed a concentration-dependent decrease in response to both forms of silver; however, AgNO3 displayed higher severity to the pigments than AgNPs. In exposure to 10 µg L-1 AgNO3, the contents of chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid, respectively, demonstrated a reduction of about 5, 3, 4, and 4 times when compared with the same respective concentration of AgNPs. Total amounts of saturated (∑SFA), monounsaturated (∑MUFA), and polyunsaturated (∑PUFA) fatty acids as well as the ratio of unsaturated to saturated ones (Unsat./Sat.) displayed somewhat similar-concentration responses. ∑SFA exhibited a hormesis response, and ∑MUFA, ∑PUFA, and Unsat./Sat. did a decreasing trend with increasing concentration of AgNPs and AgNO3. Myristoleic acid, nervonic acid, and eicosadienoic acid revealed the highest sensitivity. Pearson analysis illustrated the highest correlation among myristoleic acid, eicosenoic acid, and nervonic acid as well as among palmitic acid, stearic acid, palmitoleic acid, and oleic acid. Taken together, AgNPs and the released ions could disrupt physiological health state of microalgae through perturbation in the fatty acid composition (especially MUFAs and PUFAs) and other macromolecules. These types of bioperturbations could change the good health state of aquatic ecosystems.


Assuntos
Chlorella vulgaris/crescimento & desenvolvimento , Poluentes Ambientais/toxicidade , Ácidos Graxos/metabolismo , Nanopartículas Metálicas/toxicidade , Nitrato de Prata/toxicidade , Prata/toxicidade , Carotenoides/metabolismo , Chlorella vulgaris/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Ecossistema , Ecotoxicologia , Ácidos Graxos Monoinsaturados/metabolismo , Microalgas/efeitos dos fármacos , Testes de Toxicidade
2.
Ecotoxicol Environ Saf ; 186: 109762, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31629189

RESUMO

The use of algae is an effective approach to remove phenol and its derivatives from polluted water. The growth behavior, glucose consumption and phenol removal efficiency of Chlorella vulgaris under the synergistic effects of glucose and phenol were investigated. The evolutions of tolerance and removal efficiency of C. vulgaris to phenol under different trophic modes and glucose contents were observed. The results revealed that growth of C. vulgaris were inhibited with the increase of phenol from 0 to 400 mg L-1 in culture media; the tolerance to phenol enhanced with the addition of glucose from 2 to 10 g L-1, while glucose consumption was inhibited with the increase of phenol content; phenol removal efficiency varied with glucose concentrations in mixotrophic media. The finding suggested that phenol inhibited the growth of C. vulgaris and glucose assimilation under mixotrophic cultivation, while appropriate glucose addition could enhance the tolerance of C. vulgaris to phenol and affect the phenol removal efficiency.


Assuntos
Chlorella vulgaris/crescimento & desenvolvimento , Glucose/farmacologia , Fenol/análise , Poluentes da Água/análise , Biodegradação Ambiental , Biomassa , Chlorella vulgaris/metabolismo , Meios de Cultura/química , Relação Dose-Resposta a Droga , Glucose/metabolismo , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Fenol/metabolismo , Fenol/toxicidade , Poluentes da Água/metabolismo , Poluentes da Água/toxicidade
3.
Bioresour Technol ; 291: 121834, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31371157

RESUMO

In present study, lipids were extracted from unbroken microalga Chlorella vulgaris with high water content (50% microalgal solution) through three-phase partitioning (TPP). The method was found to extract around 15.9% of total lipid transformable to methyl esters (LTMEs) from unbroken microalgal cells which is two times of Bligh and Dyer method. We investigated the effects of various parameters on TPP performance and were optimised through response surface methodology. The results indicated that incubation duration, temperature and extraction time were positively correlated with LTME extraction efficiency. The optimum temperature was 60 °C, incubation duration was 120 min, extraction time was 60 min, ratio of solvent to DKP was 1:1. The FAME yield was calculated as 12.05% and major fatty acids together accounted for 71.33% which indicated the great potential of the proposed lipid extraction procedure for microalga-based biodiesel production.


Assuntos
Biocombustíveis , Biomassa , Chlorella vulgaris/metabolismo , Lipídeos/isolamento & purificação , Microalgas/metabolismo , Ácidos Graxos/metabolismo , Lipídeos/biossíntese , Solventes , Temperatura Ambiente , Água
4.
Sci Total Environ ; 695: 133772, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31425979

RESUMO

The widespread distribution of pharmaceuticals and personal care products (PPCPs), particularly in the built environment, has led to increased concern about their effects on both human and ecosystem health. In this research, we investigated the role of algae species Scenedesmus obliquus and Chlorella vulgaris in governing PPCP transfer and transformation mechanisms in algae-containing environments. Lab-scale algal bioreactors were created under various conditions of light, water matrix, and sterilization method to isolate and elucidate reaction mechanisms affecting carbamazepine, ibuprofen, gemfibrozil, and triclosan. The parent compounds and their potential transformation products were analyzed in both the water and algae phases. The results showed that ibuprofen was primarily biotransformed due to synergistic relationships between the algae and the bacteria. Ibuprofen biotransformation products tentatively identified as hydroxy-ibuprofen, carboxy-ibuprofen, and 4-isobutylcatechol were detected in several samples. In all the reactors exposed to light, triclosan underwent both phototransformation and biotransformation. Triclosan biotransformation took place in Scenedesmus obliquus, as demonstrated by the presence of triclosan-O-sulfate in the algae extracts. No evidence of significant carbamazepine and gemfibrozil transfer or transformation was observed under the experimental conditions tested. These results suggest that microalgal-bacterial consortia can facilitate PPCP transformation in algae-based passive water treatment systems.


Assuntos
Cosméticos/análise , Preparações Farmacêuticas/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Chlorella vulgaris/metabolismo , Cosméticos/metabolismo , Microalgas/metabolismo , Preparações Farmacêuticas/metabolismo , Águas Residuárias , Poluentes Químicos da Água/análise
5.
World J Microbiol Biotechnol ; 35(9): 141, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31463611

RESUMO

Chlorella vulgaris is an important freshwater alga that is widely used as a food source for humans and animals. High-salinity environments can cause accumulation of lipids and proteins in this species, but the mechanism of this accumulation and the salt response remain unclear. In this work, transcriptome analysis was performed for the C. vulgaris response to salt stress (1% and 3% NaCl) applied for different times (2 h and 4 h). In total, 5232 and 9196 were differentially expressed after 1% NaCl for 2 and 4 h, and 3968 and 9035 unigenes were differentially expressed after 3% NaCl for 2 and 4 h, respectively. The number of upregulated genes after 4 h of salinity stress was greater than the number of downregulated genes, suggesting that the alteration of gene expression may be related to a mechanism of adaptation to a high-salinity environment. Furthermore, gene ontology and KEGG pathway analyses revealed that numerous biological pathways are affected by salt stress. Among the upregulated pathways, the cytoplasmic calcium signaling pathway, which is involved in the regulation of homeostasis, was highly upregulated. Genes involved in the photosystem I light-harvesting pathway were downregulated under salt stress. These results provide foundational information on the effects of salt stress on C. vulgaris metabolism and its possible mechanism of surviving high concentrations of NaCl.


Assuntos
Chlorella vulgaris/efeitos dos fármacos , Chlorella vulgaris/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Estresse Salino/genética , Cloreto de Sódio/farmacologia , Transcriptoma , Chlorella vulgaris/metabolismo , Ontologia Genética , Genes de Plantas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Salinidade , Estresse Salino/fisiologia
6.
Environ Pollut ; 254(Pt A): 112942, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31376603

RESUMO

In the present study, we evaluate our previously developed non-destructive soil algal toxicity method using species from a different class of algae; Class Trebouxiophyceae (Chlorella vulgaris and Chlorella sorokiniana), and directly measure the photosynthetic activity of these species adsorbed onto the soil as a new toxicity endpoint. This study shows that non-destructive soil algal toxicity method is applicable to non-specific test species, including those of Class Trebouxiophyceae as well as Class Chlorophyceae (Chlorococcum infusionum and Chlamydomonas reinhardtii). Furthermore, by performing photosynthesis image analysis, we verify that it is possible to measure the photosynthetic activity of soil algae Chlorella vulgaris adsorbed onto soils without the need to extract algal cells from the soil. We propose that the non-destructive soil algal toxicity method represents a novel technique for 1) evaluating pollutants in soil using non-specific algae and 2) conveniently and rapidly assessing the photosynthetic activity of soil algae Chlorella vulgaris adsorbed onto soil as a new toxicity endpoint.


Assuntos
Chlorella vulgaris/metabolismo , Monitoramento Ambiental/métodos , Fotossíntese/fisiologia , Poluentes do Solo/análise , Solo/química , Adsorção , Chlamydomonas reinhardtii/metabolismo , Clorofíceas/metabolismo , Clorofila/metabolismo , Fluorescência
7.
Bioresour Technol ; 291: 121870, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31382092

RESUMO

Microalgae-based biorefinery concepts can contribute to providing sufficient resources for a growing world population. However, the performance needs to be improved, which requires innovative technologies and processes. Continuous extraction from Chlorella vulgaris cultures via pulsed electric field (PEF) processing might be a viable process to increase the performance of microalgae-based biorefinery concepts. In this study, increasing protein extraction rates were observed with increasing electric field strength, up to 96.6 ±â€¯4.8% of the free protein in the microalgae. However, increased extraction rates negatively influenced microalgae growth after PEF treatment. A free protein extraction rate up to 29.1 ±â€¯1.1% without a significant influence on microalgal growth after 168 h was achieved (p = 0.788). Within the scope of this work, a protocol for continuous protein extraction during microalgae cultivation by PEF processing was developed. The incorporation of innovative downstream into upstream processing could be a viable future concept.


Assuntos
Microalgas/metabolismo , Chlorella vulgaris/metabolismo , Eletricidade
8.
Bioresour Technol ; 291: 121821, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31352167

RESUMO

The aim of this work was to study ammonium-limited fed-batch conditions in heterotrophic C. vulgaris shake flask cultivations. Therefore, an innovative polymer-based ammonium release technique (polymer beads) was developed. Using these beads in shake flasks, C. vulgaris cultivations resulted in simultaneous growth and lipid accumulation. Lipid productivity was increased by 43% compared to batch cultivations. Furthermore, by online monitoring of the metabolic activity (RAMOS technique), unlimited growth and depletion of nutrients could be identified. A previously unknown sulfur limitation was detected in the applied Bold's Basal Medium. Combining the ammonium release beads with the RAMOS technique proved to be an efficient method for microalgae process development.


Assuntos
Compostos de Amônio/metabolismo , Chlorella vulgaris/metabolismo , Lipídeos/biossíntese , Microalgas/metabolismo , Polímeros/metabolismo
9.
Bioresour Technol ; 291: 121836, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31344632

RESUMO

The aim of this work was to study the biotreatment of mixed wastewaters collected from two points of MnO2 industry by Chlorella vulgaris. Their growth rates in four mixed wastewaters with mass ratio of wastewater 1#:2# of 20:1, 50:1, 100:1, and 200:1 were characterized, and the lag phase was shortened with increase of nitrate concentrations. The N, P, and metal removal kinetics were quantified each other day to evaluate the bio-treatment efficiencies of high-nitrate wastewaters from MnO2 industry. 84.68% and 98% of N, P has been removed. The Ca, Zn, Mn, and Si in mixed wastewaters was removed with maximum removal efficiencies of 97.91%, 99.37%, 99.44%, and 81.68%, respectively. The compositions of Chlorella vulgaris cultured in mixed wastewaters, including proteins, lipids, ash contents, and carbohydrates, were investigated in detail. The optimum HHV of Chlorella vulgaris about 18 MJ/Kg presented a potential to decrease the cost of algal biofuel.


Assuntos
Chlorella vulgaris/metabolismo , Compostos de Manganês/metabolismo , Nitratos/metabolismo , Óxidos/metabolismo , Águas Residuárias/química , Óxidos de Nitrogênio/metabolismo , Eliminação de Resíduos Líquidos/métodos
10.
Ecotoxicol Environ Saf ; 182: 109393, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299473

RESUMO

This research evaluated the influence of organic matter (OM) and CO2 addition on the bioremediation potential of two microalgae typically used for wastewater treatment: Chlorella vulgaris (CV) and Scenedesmus almeriensis (SA). The heavy metal (HM) removal efficiencies and biosorption capacities of both microalgae were determined in multimetallic solutions (As, B, Cu, Mn, and Zn) mimicking the highest pollutant conditions found in the Loa river (Northern Chile). The presence of OM decreased the total biosorption capacity, specially in As (from 2.2 to 0.0 mg/g for CV and from 2.3 to 1.7 mg/g for SA) and Cu (from 3.2 to 2.3 mg/g for CV and from 2.1 to 1.6 mg/g for SA), but its influence declined over time. CO2 addition decreased the total HM biosorption capacity for both microalgae species and inhibited CV growth. Finally, metal recovery using different eluents (HCl, NaOH, and CaCl2) was evaluated at two different concentrations. HCl 0.1 M provided the highest recovery efficiencies, which supported values over 85% of As, 92% of Cu, and ≈100% of Mn and Zn from SA. The presence of OM during the loaded stage resulted in a complete recovery of As, Cu, Mn, and Zn when using HCl 0.1 M as eluent.


Assuntos
Biodegradação Ambiental , Dióxido de Carbono/metabolismo , Chlorella vulgaris/metabolismo , Metais Pesados/metabolismo , Scenedesmus/metabolismo , Poluentes Químicos da Água/metabolismo , Chile , Metais Pesados/análise , Microalgas , Águas Residuárias , Poluentes Químicos da Água/análise
11.
Chemosphere ; 233: 140-148, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31170584

RESUMO

Polybrominated diphenyl ethers (PBDEs) are ubiquitous and toxic contaminants found in high concentrations in watercourses, and are not well removed by conventional wastewater treatment facilities. This study aimed to evaluate the removal and transformation of BDE-47, one of the environmentally predominant PBDE congener, by a green alga (Chlorella vulgaris) and a cyanobacterium (Microcystis flos-aquae) under different light conditions. Living and autoclaved cultures were exposed to BDE-47 at a concentration of 10 µg L-1 for 7 days. Both species removed >90% of BDE-47 very shortly after spiking. Light intensity affected the transformation of BDE-47 in living cultures of both species, since 5 to 11 times more debromination products were measured at a light intensity of 100 µmol photons m-2 s-1 than at 20 µmol photons m-2 s-1. Living cultures of M. flos-aquae transformed BDE-47 at a rate of 0.22 day-1 while no transformation was observed in the respective autoclaved cultures. On the contrary, both living and autoclaved cultures of C. vulgaris had similar BDE-47 transformation rates of 0.05-0.06 day-1. Debromination of BDE-47 was a predominant transformation pathway in cultures of C. vulgaris, with two times higher BDE-28 concentrations measured than in M. flos-aquae, while hydroxylation was more dominant with the cyanobacterium. Most BDE-47 and its debromination product BDE-28 were found on the cell surface of both species. These results reveal that different transformation mechanisms were involved in C. vulgaris and M. flos-aquae cultures and confirm the importance of species selection for the removal of PBDEs from contaminated environments.


Assuntos
Chlorella vulgaris/metabolismo , Éteres Difenil Halogenados/metabolismo , Microcystis/metabolismo , Biodegradação Ambiental , Chlorella vulgaris/citologia , Éteres Difenil Halogenados/química , Hidroxilação , Luz , Microcystis/citologia , Bifenil Polibromatos/metabolismo , Técnicas de Cultura de Tecidos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias
12.
Artigo em Inglês | MEDLINE | ID: mdl-31242666

RESUMO

The rare earth elements are widely used in agricultural and light industry development. They promote the growth of crop seedlings, enhance root development and change the metal properties. Due to the large amount of rare earth minerals mined in China, rare earth elements have been detected in both coastal and estuary areas. They cause pollution and threaten the health of aquatic organisms and human beings. This study investigates the effects of lanthanum on two marine bait algae, and analyzes the changes in the photosynthetic and antioxidant systems of the two algae. The results show that rare earth elements have significant inhibitory effects upon the two algae. The OJIP kinetic curve value decreases with an increasing concentration of La(NO3)3 ·6H2O. The parameters of the fluorescence value were analyzed. The ABS/RC increases and the DI0/RC decreases during the first 24 h after exposure. The effects on the photosynthetic and antioxidant systems at low concentrations (both EC10 and EC20) show that the TR0/ABS increases, and the ET0/RC, ABS/RC, and DI0/RC has a decreasing trend after 30 min. However, after 24 h, normal levels were restored. In addition, the study finds that the TR0/ABS increases after 24 h, leading to an increase in reactive oxygen species. The antioxidant system analysis also confirms the increase in the activities of antioxidant enzymes, such as SOD and GSH. The experiment is expected to support the marine pollution of rare earths and the theoretical data of the impact on marine primary producers.


Assuntos
Chlorella vulgaris/efeitos dos fármacos , Diatomáceas/efeitos dos fármacos , Lantânio/toxicidade , Poluentes Químicos da Água/toxicidade , Chlorella vulgaris/metabolismo , Diatomáceas/metabolismo , Glutationa/metabolismo , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
13.
Environ Toxicol Pharmacol ; 70: 103208, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31207443

RESUMO

Boron (B) has been widely used and contaminated the aquatic ecosystem. However, knowledge of the effects of sodium pentaborate pentahydrate (SPP) on algae remains limited. This study aimed to assess SPP toxicity using multiple endpoints, specially detecting the intracellular metal ion concentrations, malondialdehyde (MDA) content and extracellular polymeric substance (EPS) classes for the very first time during SPP exposure to Chlorella vulgaris (C. vulgaris). Our findings indicated that the inhibitory effects of SPP on C. vulgaris may be related to nutrient absorption and utilization. The changes in intracellular starch grains, MDA and the protein-like substances in EPS probably acted as a defense mechanism, helping to alleviate the toxic effects. This work may contribute to the understanding of the mechanism of SPP toxicity in algae. Further studies may focus on the effects of B on speciation of metallic ions and the interaction of B with metallic ions on aquatic organisms.


Assuntos
Boratos/toxicidade , Chlorella vulgaris/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Chlorella vulgaris/crescimento & desenvolvimento , Chlorella vulgaris/metabolismo , Chlorella vulgaris/ultraestrutura , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Malondialdeído/metabolismo , Microscopia Eletrônica de Transmissão
14.
Bioresour Technol ; 289: 121689, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31252316

RESUMO

In the present study, catalytic pyrolysis of Chlorella vulgaris biomass was conducted to analyse the kinetic and thermodynamic performances through thermogravimetric approach. HZSM-5 zeolite, limestone (LS), bifunctional HZSM-5/LS were used as catalysts and the experiments were heated from 50 to 900 °C at heating rates of 10-100 °C/min. Iso-conversional model-free methods such as Flynn-Wall-Ozawa (FWO), Kissinger-Akahira-Sunose (KAS), Starink's, and Vyazovkin (V) were employed to evaluate the kinetic parameters meanwhile the thermodynamic parameters were determined by using FWO and KAS methods. The calculated EA values of non-catalytic and catalytic pyrolysis of HZSM-5 zeolite, LS, and bifunctional HZSM-5/LS were determined to be in the range of 156.16-158.10 kJ/mol, 145.26-147.84 kJ/mol, 138.81-142.06 kJ/mol, and 133.26 kJ/mol respectively. The results have shown that catalytic pyrolysis with the presence of bifunctional HZSM-5/LS resulted to a lower average EA and ΔH compared to HZSM-5, and LS which indicated less energy requirement in the process.


Assuntos
Chlorella vulgaris/metabolismo , Biocatálise , Biomassa , Temperatura Alta , Cinética , Pirólise , Termodinâmica , Termogravimetria
15.
Environ Sci Pollut Res Int ; 26(18): 18520-18532, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31049862

RESUMO

The present work investigated the potential of the green alga Chlorella vulgaris to produce high-quality biofuel under culture stress conditions. The cultivation was carried out in a 1000 l open plate tank system, which provides biomass yields comparable to open pond systems, but with less area needed. Algal biomass and lipid content were measured repeatedly. We compared the two solvent systems n-hexane and hexane/isopropanol (HIP) for extraction efficiency of lipids and applied three different extraction methods Soxhlet, soaking, and soaking followed by Soxhlet (soak-Sox). The combination of the HIP solvent and the soak-Sox provided the highest lipid yield (15.8 ± 0.174). Volumetric biomass and lipid productivity were 0.201 g l-1 day-1 and 31.71 mg l-1 day-1, respectively, whereas areal biomass and lipid productivity were 25.73 g m-2 day-1 and 4.066 g m-2 day-1, respectively. The fatty acid profile by means of gas chromatography resulted in seven fatty acids from C12 to C18. The most abundant fatty acid methyl esters (FAMES) were palmitic (C16:0), oleic (C18:1), and stearic (C18:0) acids. Lipid synthesis enhanced by optimizing the Kuhl growth medium with replacing nitrate by urea (50% N compared to the original recipe) increased salt content (10 g/l NaCl), ferrous sulfate (0.5 g/l), and sodium acetate addition (1 g/l). With regard to density, kinematic viscosity, gravity, pour point, flash point, and cetane number, the Chlorella-biodiesel comply with ASTM and EN standards thus pointing at the high potential of lipids synthesized by Chlorella as a feedstock for biodiesel production.


Assuntos
Biocombustíveis/análise , Biotecnologia/métodos , Chlorella vulgaris/crescimento & desenvolvimento , Ácidos Graxos/análise , Microalgas/crescimento & desenvolvimento , Biomassa , Biotecnologia/instrumentação , Chlorella vulgaris/metabolismo , Meios de Cultura/química , Microalgas/metabolismo
16.
Sci Total Environ ; 677: 120-130, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31055095

RESUMO

Nowadays, due to worldwide water shortage, water utilities are forced to re-evaluate treated wastewater. Consequently, wastewater treatment plants need to conduct biomonitoring. Coking wastewater (CWW) has toxic, mutative and carcinogenic components with threatening effect on the environment. CWW was selected as a model for complex highly toxic industrial wastewater that should be treated. CWW from Egypt was treated in a nine-liter photobioreactor using an algal-bacterial system. The photobioreactor was operated for 154 days changing different parameters (toxic load and light duration) for optimization. Optimized conditions achieved significant reduction (45%) in the operation cost. The algal-bacterial system was monitored using chemical assays (chemical oxygen demand and phenol analysis), bioassays (phytotoxicity, Artemia-toxicity, cytotoxicity, algal-bacterial ratio and settleability) and Illumina-MiSeq sequencing of 16S rRNA gene. The algal-bacterial system detoxified (in terms of phytotoxicity, cytotoxicity and Artemia-toxicity) CWW introduced as influent through all phases. A significant difference was recorded in the microbial diversity between influent and effluent samples. Four phyla dominated influent samples; Proteobacteria (77%), Firmicutes (11%), Bacteroidetes (5%) and Deferribacteres (3%) compared to only two in effluent samples; Proteobacteria (66%) and Bacteroidetes (26%). The significant relative-abundance of versatile aromatic degraders (Comamonadaceae and Pseudomonadaceae families) in influent samples conformed to the nature of CWW. Microbial community shifted and promoted the activity of catabolically versatile and xenobiotics degrading families (Chitinophagaceae and Xanthomonadaceae). Co-culture of microalgae had a positive effect on the biodegrading bacteria that was reflected by enhanced treatment efficiency, significant increase in relative abundance of bacterial genera with cyanide-decomposing potential and negative effect on waterborne pathogens.


Assuntos
Bactérias/metabolismo , Chlorella vulgaris/metabolismo , Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos , Águas Residuárias/análise , Águas Residuárias/microbiologia , Coque , Egito , Microalgas/metabolismo , Microbiota , Poluentes Químicos da Água/análise , Poluição Química da Água/prevenção & controle
17.
Int J Biol Macromol ; 135: 1-11, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31121228

RESUMO

Microalgae are the lowest plant organisms producing a wide range of metabolites that make them interesting organisms for industrial applications. Cultivation of green microalgal species Chlorella vulgaris resulted a significant production of extracellular polysaccharide (EPS). Preliminary chemico-spectroscopic studies on EPS revealed its molecular profile, a complex primary structure consisting of six monosaccharide units occurring in both furano and pyrano forms, a high sugar binding variability and the presence of partially methylated derivatives of some sugar constituents. Biological activity tests showed that EPS caused significant bronchodilatory, anti-inflammatory and antitussive effects in test animals. Chlorella EPS appears to be a promising agent for the prevention of chronic airway inflammation, which is the basic pathogenic mechanism of many respiratory diseases, including bronchial asthma.


Assuntos
Antiasmáticos/química , Antiasmáticos/farmacologia , Chlorella vulgaris/metabolismo , Polissacarídeos/química , Polissacarídeos/farmacologia , Alérgenos , Animais , Antiasmáticos/metabolismo , Hiper-Reatividade Brônquica/tratamento farmacológico , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/fisiopatologia , Fenômenos Químicos , Citocinas/metabolismo , Modelos Animais de Doenças , Espaço Extracelular/metabolismo , Cobaias , Mediadores da Inflamação/metabolismo , Masculino , Músculo Liso/efeitos dos fármacos , Músculo Liso/imunologia , Músculo Liso/metabolismo , Polissacarídeos/biossíntese , Análise Espectral
18.
Int J Biol Macromol ; 134: 976-983, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31121230

RESUMO

The production, physicochemical characteristics, antioxidant and antitumor activities of partial purified exopolysaccharides from Chlorella zofingiensis, Chlorella vulgaris were investigated. The final exopolysaccharides productions were 208.4, 364.3 mg/L and the average molecular weights were 2.66×104, 1.88×104 Da, respectively. Monosaccharide analysis indicating that these exopolysaccharides consisted of 10 or 11 different kinds of sugars and derivatives, respectively. Additionally, they exhibited obvious radical scavenging activities on DPPH and hydroxyl radicals, which reached to 59.6-71.5% and 44.5-70.4%, respectively. Moreover, the antitumor effects were studied using human colon cancer cell lines HCT8. The results showed that they had significant antitumor effects considering the inhibitory effects on cell viabilities (28.3-18.0% on HCT8, respectively). Thus, these exopolysaccharides from microalgae species are worth further investigating as alternative potential antitumor agents.


Assuntos
Antineoplásicos/química , Antineoplásicos/metabolismo , Chlorella vulgaris/metabolismo , Chlorella/metabolismo , Polissacarídeos Fúngicos/biossíntese , Polissacarídeos Fúngicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Polissacarídeos Fúngicos/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Peso Molecular , Monossacarídeos/química
19.
Appl Biochem Biotechnol ; 189(1): 193-205, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30969398

RESUMO

Utilization of low-cost raw materials for the bio-based chemical production, such as carotenoids, by the co-culture of Rhodotorula glutinis and Chlorella vulgaris has recently become an attractive option. In this study, the primary nutrients of starch wastewater were analyzed, which were used for carotenoid production by the co-culture strategy in a 5-L fermenter around 4000 Lux light intensity. Synergistic effect of gas utilization revealed that the two species could build up the beneficial balance on mutualism. The maximum carotenoid productivity and COD removal efficiency were 12.34 mg/L and 79.6%, respectively, which were higher than those of monoculture yeast (8.31 mg/L and 54.1%). The organic acids, amino acids, and sugar removal efficiencies were increased by 85%, 31%, and 44%, respectively, and more than three kinds of carotenoids were identified compared with those of monoculture yeast. The results demonstrated that the co-culture strategy of two different nutritional microorganisms could significantly improve carotenoid productivity and COD removal efficiency.


Assuntos
Análise da Demanda Biológica de Oxigênio , Carotenoides/isolamento & purificação , Chlorella vulgaris/metabolismo , Rhodotorula/metabolismo , Águas Residuárias , Técnicas de Cocultura
20.
Int J Mol Sci ; 20(8)2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31018518

RESUMO

Anthropogenic activities have increased the amount of urban wastewater discharged into natural aquatic reservoirs containing a high amount of nutrients such as phosphorus (Pi and PO 4 - 3 ), nitrogen (NH 3 and NO 3 - ) and organic contaminants. Most of the urban wastewater in Mexico do not receive any treatment to remove nutrients. Several studies have reported that an alternative to reduce those contaminants is using consortiums of microalgae and endogenous bacteria. In this research, a genome-scale biochemical reaction network is reconstructed for the co-culture between the microalga Chlorella vulgaris and the bacterium Pseudomonas aeruginosa. Metabolic Pathway Analysis (MPA), is applied to understand the metabolic capabilities of the co-culture and to elucidate the best conditions in removing nutrients. Theoretical yields for phosphorus removal under photoheterotrophic conditions are calculated, determining their values as 0.042 mmol of PO 4 - 3 per g DW of C. vulgaris, 19.43 mmol of phosphorus (Pi) per g DW of C. vulgaris and 4.90 mmol of phosphorus (Pi) per g DW of P. aeruginosa. Similarly, according to the genome-scale biochemical reaction network the theoretical yields for nitrogen removal are 10.3 mmol of NH 3 per g DW of P. aeruginosa and 7.19 mmol of NO 3 - per g DW of C. vulgaris. Thus, this research proves the metabolic capacity of these microorganisms in removing nutrients and their theoretical yields are calculated.


Assuntos
Chlorella vulgaris/metabolismo , Redes e Vias Metabólicas , Nitrogênio/metabolismo , Fósforo/metabolismo , Pseudomonas aeruginosa/metabolismo , Técnicas de Cocultura , Águas Residuárias/microbiologia , Purificação da Água
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