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1.
Mar Drugs ; 18(10)2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32993146

RESUMO

For a long time, algal chemistry from terrestrial to marine or freshwater bodies, especially chlorophytes, has fascinated numerous investigators to develop new drugs in the nutraceutical and pharmaceutical industries. As such, chlorophytes comprise a diverse structural class of secondary metabolites, having functional groups that are specific to a particular source. All bioactive compounds of chlorophyte are of great interest due to their supplemental/nutritional/pharmacological activities. In this review, a detailed description of the chemical diversity of compounds encompassing alkaloids, terpenes, steroids, fatty acids and glycerides, their subclasses and their structures are discussed. These promising natural products have efficiency in developing new drugs necessary in the treatment of various deadly pathologies (cancer, HIV, SARS-CoV-2, several inflammations, etc.). Marine chlorophyte, therefore, is portrayed as a pivotal treasure in the case of drugs having marine provenience. It is a domain of research expected to probe novel pharmaceutically or nutraceutically important secondary metabolites resulting from marine Chlorophyta. In this regard, our review aims to compile the isolated secondary metabolites having diverse chemical structures from chlorophytes (like Caulerpa ssp., Ulva ssp., Tydemania ssp., Penicillus ssp., Codium ssp., Capsosiphon ssp., Avrainvillea ssp.), their biological properties, applications and possible mode of action.


Assuntos
Produtos Biológicos/farmacologia , Clorófitas/química , Clorófitas/metabolismo , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antivirais/química , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Produtos Biológicos/química , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Humanos , Neoplasias/tratamento farmacológico , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia
2.
Proc Natl Acad Sci U S A ; 117(24): 13588-13595, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32482859

RESUMO

Viruses, microbes, and host macroorganisms form ecological units called holobionts. Here, a combination of metagenomic sequencing, metabolomic profiling, and epifluorescence microscopy was used to investigate how the different components of the holobiont including bacteria, viruses, and their associated metabolites mediate ecological interactions between corals and turf algae. The data demonstrate that there was a microbial assemblage unique to the coral-turf algae interface displaying higher microbial abundances and larger microbial cells. This was consistent with previous studies showing that turf algae exudates feed interface and coral-associated microbial communities, often at the detriment of the coral. Further supporting this hypothesis, when the metabolites were assigned a nominal oxidation state of carbon (NOSC), we found that the turf algal metabolites were significantly more reduced (i.e., have higher potential energy) compared to the corals and interfaces. The algae feeding hypothesis was further supported when the ecological outcomes of interactions (e.g., whether coral was winning or losing) were considered. For example, coral holobionts losing the competition with turf algae had higher Bacteroidetes-to-Firmicutes ratios and an elevated abundance of genes involved in bacterial growth and division. These changes were similar to trends observed in the obese human gut microbiome, where overfeeding of the microbiome creates a dysbiosis detrimental to the long-term health of the metazoan host. Together these results show that there are specific biogeochemical changes at coral-turf algal interfaces that predict the competitive outcomes between holobionts and are consistent with algal exudates feeding coral-associated microbes.


Assuntos
Antozoários/metabolismo , Clorófitas/metabolismo , Animais , Antozoários/química , Antozoários/microbiologia , Antozoários/parasitologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Clorófitas/química , Recifes de Corais , Ecossistema , Metagenômica , Microbiota
3.
Poult Sci ; 99(4): 2100-2107, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32241495

RESUMO

The present study was conducted to evaluate the effects of dietary marine-derived polysaccharides (MDP) from seaweed Enteromorpha on productive performance, egg quality, antioxidant capacity, and jejunal morphology in late-phase laying hens. A total of 240 Lohmann white laying hens (62 wk of age) were assigned to 4 dietary treatments that included MDP at concentrations of 0, 1,000, 2,500, and 5,000 mg/kg for 6 wk. Each treatment had 6 replicates with 5 cages (2 birds/cage). The results showed that dietary MDP quadratically improved egg production (P < 0.05) during 5 to 6 wk and 1 to 6 wk. There was a linear reduction in cracked egg rate (P < 0.05) with dietary MDP levels increased during 3 to 4 wk and 1 to 6 wk. After 4 wk of feeding trial, the egg shell thickness, yolk color, and Haugh unit showed a linear increase (P < 0.05) in response to increasing dietary MDP levels. Besides, the egg shell breaking strength, egg shell thickness, yolk color, and Haugh unit were improved linearly (P < 0.05) by dietary MDP at the end of the experiment. Moreover, dietary MDP showed a linear and quadratic reduction in serum malondialdehyde (MDA) content (P < 0.05) at the end of third week. At the end of experiment, the activity of total superoxide dismutase in serum was increased quadratically (P < 0.05) by dietary MDP, and dietary MDP quadratically improved the liver catalase (CAT) activity (P < 0.05) and linearly enhanced jejunal CAT activity (P < 0.05), whereas linearly decreased jejunal MDA concentration (P < 0.05). Furthermore, supplemental MDP linearly improved the villus height (P < 0.05) and quadratically increased villus height/crypt depth ratio (P < 0.05) of jejunum. However, dietary MDP had no effect on jejunal trypsin, amylase, and protease activity (P > 0.10). Taken together, these findings provided new insights into the role of MDP in improving the productive performance, egg quality, antioxidant capacity, and jejunal morphology of late-phase laying hens.


Assuntos
Antioxidantes/metabolismo , Galinhas/fisiologia , Clorófitas/química , Carboidratos da Dieta/metabolismo , Jejuno/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Polissacarídeos/metabolismo , Ração Animal/análise , Animais , Galinhas/anatomia & histologia , Dieta/veterinária , Carboidratos da Dieta/administração & dosagem , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Feminino , Jejuno/anatomia & histologia , Óvulo/fisiologia , Polissacarídeos/administração & dosagem , Distribuição Aleatória
4.
Mar Drugs ; 18(4)2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32344720

RESUMO

Monostroma nitidum is a green single-cell layered algae that grows on the southwest coast of Japan. It is often used for salad ingredients, boiled tsukudani, soups, etc., due to its health benefits. M. nitidum is composed of many cell aggregates, and the various substances that fill the intercellular space are dietary fibers, vitamins, and minerals. Rhamnan sulfate (RS), a sulfated polysaccharide, is main the component of the fiber extracted from M. nitidum. Recently, some biological properties of RS have been demonstrated by in vitro and in vivo studies that probably protect human subjects from viruses and ameliorate vascular dysfunction caused by metabolic disorders, especially lifestyle-related diseases. In this review, we focus on the antithrombotic effects of RS and introduce its antiviral and other biological activities.


Assuntos
Clorófitas/química , Desoxiaçúcares/farmacologia , Mananas/farmacologia , Animais , Antivirais/isolamento & purificação , Antivirais/farmacologia , Desoxiaçúcares/isolamento & purificação , Fibrinolíticos/isolamento & purificação , Fibrinolíticos/farmacologia , Humanos , Japão , Mananas/isolamento & purificação , Sulfatos
5.
Environ Monit Assess ; 192(5): 316, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32342228

RESUMO

Zayandeh-Rud River is the only permanent river in the central plateau of Iran. This river has been subject to an extensive discharge of wastewater and effluents from several point and nonpoint pollution sources. Accordingly, sediment quality of Zayandeh-Rud River in Varzaneh region, were studied. Algae and the sediment were sampled through 3 replications at 6 stations in the downstream after crossing through the Isfahan city and reaching Gavkhuni international wetland. Chlorophyll content and As, Pb, and Cd concentrations were measured in each sample Cladophora sp. and Oscillatoria sp. were identified using standard identification keys. The mean concentrations of metals in all stations exceeded background levels. Mean concentration of arsenic (162.9 mg/kg) in the sediment is about 31 times more than the ISQG standard (5.9 mg/kg) and considerably higher than the similar studies in Iran and other regions of the world. The mean concentration of As in algae samples is higher than the most polluted areas of the world. The mean concentration of Pb in the sediment (19.69 mg/kg) is lower than the ISQGs standard (35 mg/kg) and most of the studied river in north of Iran such as Chalous, Baboul-Rud, Gorgan-Rud (North), Khiav (North West), and Anzali wetland. The mean concentration of Cd in the sediment (2.11 mg/kg) is significantly higher than ISQG standard (0.6 mg/kg and some north highly polluted wetlands of Iran such as Anzali. There is a significant positive correlation between the mean concentrations of As and Pb in the sediment and Cladophora sp. tissue, and a negative one between the mean concentration of Pb in the sediment and chlorophyll b/a. There are significant negative correlations between the mean concentration of As in the sediment and chlorophyll a, and the total chlorophyll concentration in Oscillatoria sp. The results of Muller index indicate that the concentrations of Pb, Cd, and As in all stations occur in the Unpolluted, Moderate/Heavy, and Heavy/Extreme groups, respectively. Degree of contamination and modified degree of contamination show very high degree of pollution in the studied area. RI in all the stations showed very high ecological risk. The bioaccumulation factor for all metals in both algae is less than one. So, these two species may not be described as heavy metal accumulators. This study is an alarm for the Zayandeh-Rud River as the most important freshwater source for the Iranian Plateau. Graphical abstract.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados , Poluentes Químicos da Água , Clorofila A/análise , Clorófitas/química , Cidades , Sedimentos Geológicos/química , Irã (Geográfico) , Metais Pesados/análise , Medição de Risco , Poluentes Químicos da Água/análise
6.
Biochemistry ; 59(14): 1398-1409, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32208646

RESUMO

Marine algae are a major source of ω-3 long-chain polyunsaturated fatty acids (ω3-LCPUFAs), which are conditionally essential nutrients in humans and a target for industrial production. The biosynthesis of these molecules in marine algae requires the desaturation of fatty acids by Δ6-desaturases, and enzymes from different species display a range of specificities toward ω3- and ω6-LCPUFA precursors. In the absence of a molecular structure, the structural basis for the variable substrate specificity of Δ6-desaturases is poorly understood. Here we have conducted a consensus mutagenesis and ancestral protein reconstruction-based analysis of the Δ6-desaturase family, focusing on the ω3-specific Δ6-desaturase from Micromonas pusilla (MpΔ6des) and the bispecific (ω3/ω6) Δ6-desaturase from Ostreococcus tauri (OtΔ6des). Our characterization of consensus amino acid substitutions in MpΔ6des revealed that residues in diverse regions of the protein, such as the N-terminal cytochrome b5 domain, can make important contributions to determining substrate specificity. Ancestral protein reconstruction also suggests that some extant Δ6-desaturases, such as OtΔ6des, could have adapted to different environmental conditions by losing specificity for ω3-LCPUFAs. This data set provides a map of regions within Δ6-desaturases that contribute to substrate specificity and could facilitate future attempts to engineer these proteins for use in biotechnology.


Assuntos
Clorófitas/enzimologia , Linoleoil-CoA Desaturase/química , Linoleoil-CoA Desaturase/genética , Clorófitas/química , Clorófitas/classificação , Clorófitas/genética , Ácidos Graxos Ômega-3/química , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-6/química , Ácidos Graxos Ômega-6/metabolismo , Linoleoil-CoA Desaturase/metabolismo , Família Multigênica , Mutagênese , Filogenia , Conformação Proteica , Especificidade por Substrato
7.
Ecotoxicol Environ Saf ; 195: 110488, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32200143

RESUMO

Effect of water accommodated fractions (WAF) of #180 fuel oil on fixed carbon and nitrogen in microalgae was studied by stable isotopes. Platymonas helgolandica, Heterosigma akashiwo and Nitzschia closterium were exposed to five WAF concentrations for 96 h. The δ13C value of microalgae was significantly lower than that of the control group, indicated that carbon was limited in the WAF concentrations. The δ13C value of microalgae appeared peak valley at 48 h in control group, corresponding to the enhanced capacity in carbon fixation during microalgae photosynthesis. The physiological acclimation capacity of microalgae was revealed by the occurrence time when the δ13C value was in peak valley, and thus the physiological acclimation capacity of microalgae decreased in the order of Nitzschia closterium > Heterosigma akashiwo > Platymonas helgolandica. Principal component analysis (PCA) were applied to the δ13C value in order to verify the "hormesis" phenomenon in microalgae. The δ13C value could discriminate between stimulatory effects at low doses and inhibitory effects at high doses. In addition, the present study also investigated the effect of the nitrogen on microalgae growth. Because microalgae could still absorb the NO3-N and release of NO2-N and NH4-N in present study, the nitrogen cycle in microalgae was in the equilibrium status. The δ15N value in microalgae exhibited no obvious change with the increasing of WAF concentrations at the same time. However, due to the enrichment of nitrogen, the δ15N value first increased gradually with the time and finally was stable. Overall, the fractionation of carbon and nitrogen stable isotopes illustrated that the effect of carbon on the growth of microalgae was more prominent than nitrogen. Stable isotopes was used to investigate the influence of WAF on fixed carbon and nitrogen in microalgae growth, providing a fundamental theoretical guidance for risk assessment of marine ecological environment.


Assuntos
Carbono/análise , Óleos Combustíveis/toxicidade , Microalgas/efeitos dos fármacos , Nitrogênio/análise , Poluentes Químicos da Água/toxicidade , Ciclo do Carbono/efeitos dos fármacos , Isótopos de Carbono/análise , Clorófitas/química , Clorófitas/efeitos dos fármacos , Clorófitas/crescimento & desenvolvimento , Diatomáceas/química , Diatomáceas/efeitos dos fármacos , Diatomáceas/crescimento & desenvolvimento , Microalgas/química , Microalgas/crescimento & desenvolvimento , Isótopos de Nitrogênio/análise , Fotossíntese/efeitos dos fármacos , Estramenópilas/química , Estramenópilas/efeitos dos fármacos , Estramenópilas/crescimento & desenvolvimento , Água/química , Poluentes Químicos da Água/química
8.
BMC Bioinformatics ; 21(1): 1, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31898485

RESUMO

BACKGROUND: The green microalga Dunaliella salina accumulates a high proportion of ß-carotene during abiotic stress conditions. To better understand the intracellular flux distribution leading to carotenoid accumulation, this work aimed at reconstructing a carbon core metabolic network for D. salina CCAP 19/18 based on the recently published nuclear genome and its validation with experimental observations and literature data. RESULTS: The reconstruction resulted in a network model with 221 reactions and 212 metabolites within three compartments: cytosol, chloroplast and mitochondrion. The network was implemented in the MATLAB toolbox CellNetAnalyzer and checked for feasibility. Furthermore, a flux balance analysis was carried out for different light and nutrient uptake rates. The comparison of the experimental knowledge with the model prediction revealed that the results of the stoichiometric network analysis are plausible and in good agreement with the observed behavior. Accordingly, our model provides an excellent tool for investigating the carbon core metabolism of D. salina. CONCLUSIONS: The reconstructed metabolic network of D. salina presented in this work is able to predict the biological behavior under light and nutrient stress and will lead to an improved process understanding for the optimized production of high-value products in microalgae.


Assuntos
Carbono/metabolismo , Clorófitas/metabolismo , Microalgas/metabolismo , Carbono/química , Carotenoides/química , Carotenoides/metabolismo , Clorófitas/química , Clorófitas/efeitos da radiação , Cloroplastos/química , Cloroplastos/metabolismo , Citosol/química , Citosol/metabolismo , Luz , Redes e Vias Metabólicas , Microalgas/química , Microalgas/efeitos da radiação , Mitocôndrias/química , Mitocôndrias/metabolismo , Modelos Biológicos , Estresse Fisiológico
9.
Ecotoxicol Environ Saf ; 191: 110226, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31981955

RESUMO

Since 2006, harmful dinoflagellate blooms of Cochlodinium geminatum have infrequently occurred in the Pearl River Estuary, South China. During late October to early November in 2018, C. geminatum blooms occurred again in the region. To investigate the blooming mechanism in certain temporal conditions, we analysed the changes in the environmental parameters and phytoplankton community structure during and after the bloom. The results indicated that the water temperature and salinity had large impacts on the bloom. During the C. geminatum bloom, the phytoplankton community structure changed and the number of dominant species decreased. After the bloom, the species number and abundance of diatoms increased, as the species diversity was recovering. Retinal was detected in the field samples and cultured C. geminatum. It has been demonstrated to exist in some algae species (e.g. Cyanophyta, Chlorophyta, Bacillariophyta, and Euglenophyt), and our results indicates that such teratogens also exist in dinoflagellates. The highest concentration of retinal was detected during the bloom. This result indicates that the retinal content may accumulate during a bloom. Retinal has been demonstrated to be a teratogenic agent and may therefore present a potential risk to aquatic organisms during a bloom episode. This research provided more comprehensive information concerning the ecological influences of C. geminatum blooms.


Assuntos
Dinoflagelados/química , Dinoflagelados/crescimento & desenvolvimento , Estuários , Retinoides/análise , Teratogênios/análise , China , Clorófitas/química , Diatomáceas/isolamento & purificação , Fenômenos Ecológicos e Ambientais , Fitoplâncton/isolamento & purificação , Rios , Salinidade
10.
Mar Biotechnol (NY) ; 22(2): 194-206, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31970542

RESUMO

Melanoma is a form of skin cancer with high mortality owing to its fast progression and metastatic capacity. The treatments available nowadays are only palliative in advanced stages of the disease. Thus, alternative therapies for cancer treatment are in demand, and molecules from natural sources, such as polysaccharides, could represent new possible therapeutic approaches. Polysaccharides of freshwater and marine algae with biological activities, such as antitumor properties, are greatly reported in the scientific literature. In the present study, a sulfated heterorhamnan obtained from the green seaweed Gayralia brasiliensis (Gb1 fraction) was chemically characterized and its biological activities in the B16-F10 murine melanoma cell line were evaluated. The Gb1 polysaccharidic fraction tested concentrations presented low or absence of cytotoxicity to B16-F10 cells and neither cell proliferation nor cell cycle were altered. Interestingly, Gb1 treatment decreased B16-F10 cells migration and invasion capabilities and CD44 labeling, showing to be a promising compound for further in vitro and in vivo antitumor studies.


Assuntos
Clorófitas/química , Desoxiaçúcares/farmacologia , Mananas/farmacologia , Melanoma/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Movimento Celular , Desoxiaçúcares/toxicidade , Mananas/toxicidade , Camundongos , Invasividade Neoplásica , Sulfatos
11.
Environ Pollut ; 258: 113702, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31818626

RESUMO

The removal of antibiotics has attracted much attention due to their extremely high adverse impacts on the environment. However, the potential risks of degradation intermediates are seldom reported. In this work, the influence of different factors on the electro-catalytic degradation efficiency of tetracycline hydrochloride (TCH) by the prepared carbon nanotubes/agarose/indium tin oxide (CNTs/AG/ITO) electrode was investigated. Under optimal conditions (10 wt% CNTs dosage, pH = 7), the maximum degradation efficiency for TCH (10 mg L-1) reached up to 96% within 30 min treatment with 4 V potential. Superoxide anions (•O2-) played an important role in the electro-catalytic degradation. Totally 10 degradation intermediates were identified using HPLC-MS/MS, and the degradation pathway was proposed. Toxicities of the parent antibiotic and the identified intermediates were calculated using the ECOSAR (Ecological Structure Activity Relationship) program in EPISuite, and results showed that more toxic intermediates were generated. The maximal chronic toxicity for green algae of the intermediate increased 1439.92 times. Furthermore, antimicrobial activity was further verified by disk agar biocidal tests with Escherichia coli ATCC25922 and higher biotoxicity intermediates compared with parent compounds were confirmed to be formed. Therefore, more attention should be paid on the potential risk of degradation intermediates in the treatment of wastewater containing antibiotics.


Assuntos
Tetraciclina/química , Poluentes Químicos da Água/química , Catálise , Clorófitas/química , Escherichia coli/efeitos dos fármacos , Nanotubos de Carbono , Espectrometria de Massas em Tandem , Tetraciclina/toxicidade , Testes de Toxicidade , Poluentes Químicos da Água/toxicidade
12.
J Biosci Bioeng ; 129(1): 86-92, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31302007

RESUMO

The unicellular green microalga Haematococcus pluvialis accumulates large amounts of the red ketocarotenoid astaxanthin. Aiming to cultivate these microalgae with high astaxanthin efficiency, cultivations were scaled-up from 1000 mL bottle to 2 L and 8 L airlift photobioreactor using volumetric power consumption rate (W/m3) as scale up strategy. After cultivations, computational fluid dynamics (CFD) simulation was used to investigate the flow patterns, mixing efficiency and gas holdup profile within the 2 L photobioreactor. At the end, astaxanthin content was enhanced with increasing the cultivation volume and highest astaxanthin amount of 49.39 ± 1.64 mg/g cell was obtained in 8 L photobioreactor. Hydrodynamic characteristics of photobioreactor was simulated and gas holdup showed difference between the riser and the downcomer regions. Velocity profiles of air and medium had higher values inside the draft tube than obtained in downcomer region. However liquid circulation was achieved from draft tube to the downcomer, mixing was not provided effectively considering the turbulence kinetic energy. For the further research, some developments about column configuration, sparger diameter may be necessary to enhance the mixing characteristics.


Assuntos
Clorófitas/metabolismo , Microalgas/metabolismo , Fotobiorreatores , Clorófitas/química , Clorófitas/crescimento & desenvolvimento , Clorófitas/efeitos da radiação , Hidrodinâmica , Cinética , Luz , Microalgas/química , Microalgas/crescimento & desenvolvimento , Microalgas/efeitos da radiação , Xantofilas/química , Xantofilas/metabolismo
13.
J Nat Med ; 74(1): 127-134, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31432315

RESUMO

Advanced glycation end products (AGEs) induce inflammation and contribute to the pathogenesis of atherosclerosis. Although many studies have demonstrated the protective effects of carotenoids against atherosclerosis, the effects of carotenoids on AGE-induced inflammation have not been characterized. As such, we aimed to identify carotenoids that provided protection against AGE-elicited inflammation. AGE-stimulated RAW264 macrophages were first evaluated for NO generation. Among 17 carotenoids tested, only siphonaxanthin significantly suppressed it. Next, mRNA expression levels were measured in RAW264 macrophages and human umbilical vascular endothelial cells following siphonaxanthin and AGE treatment. Siphonaxanthin significantly suppressed AGE-induced mRNA expression of interleukin-6 and cellular adhesion molecules, which are known to be important for the pathogenesis of atherosclerosis. Siphonaxanthin also significantly suppressed endoplasmic reticulum (ER) stress marker genes. A reporter gene assay revealed that siphonaxanthin, as well as an ER stress inhibitor, significantly inhibited AGE-induced nuclear factor-κB (NF-κB) activation. Altogether, mitigation of ER stress and subsequent NF-κB activation is one of the molecular mechanisms by which siphonaxanthin suppressed AGE-elicited inflammation. Siphonaxanthin is a carotenoid commonly found in standard diets and is considered relatively safe for human consumption, and hence, dietary intake of siphonaxanthin or siphonaxanthin-containing green algae could be beneficial in lowering the risk of developing atherosclerosis.


Assuntos
Clorófitas/química , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Produtos Finais de Glicação Avançada/metabolismo , Inflamação/tratamento farmacológico , Xantofilas/farmacologia , Animais , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Interleucina-6/imunologia , Camundongos , NF-kappa B/metabolismo , Células RAW 264.7
14.
Anal Bioanal Chem ; 412(3): 589-599, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31838555

RESUMO

The green microalga Haematococcus pluvialis has been widely studied due to its capacity to accumulate great amounts of astaxanthin, a high-value carotenoid with biological activities. In the present work, two green compressed fluid-based processes, pressurized liquid extraction (PLE) and supercritical antisolvent fractionation (SAF), are integrated to obtain an astaxanthin-enriched extract from this microalga. PLE was carried out using pressurized ethanol as solvent, for 20 min, at 10 MPa, and 50 °C as extraction temperature. Subsequently, the obtained extract was processed by SAF to further purify the carotenoid fraction. The SAF process was optimized using a 3-level factorial experimental design and considering three experimental variables: (i) CO2 pressure (10-30 MPa), (ii) percentage of water in the PLE extract (20-50%), and (iii) PLE extract/supercritical-CO2 flow rate ratio (0.0125-0.05). Total carotenoid content was evaluated in both extracts and raffinates. Best results were obtained at 30 MPa, 0.05 feed/SC-CO2 mass flow rate, and 20% (v/v) of water in the feed solution, achieving values of 120.3 mg g-1 carotenoids in extract (in the SAF extract fraction), which were significantly higher than those obtained in the original PLE extract. In parallel, a new fast two-dimensional comprehensive liquid chromatography (LC×LC) method was optimized to get the full carotenoid profile of these extracts in less than 25 min. This is the first time that the use of a C30 column is reported in an on-line LC×LC system. Graphical abstract.


Assuntos
Clorófitas/química , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Espectrofotometria Ultravioleta , Xantofilas/química
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117382, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31357053

RESUMO

Fourier transform infrared (FTIR) and Raman spectroscopic techniques were employed to analyze the biomolecular transitions and lipid accumulation in three freshwater green microalgal species, Monoraphidium contortum (M. contortum), Pseudomuriella sp. and Chlamydomonas sp. during various phases of their growth. Biomolecular transitions and lipid [hydrocarbons, triacylglycerides (TAGs)] accumulation within the microalgal cells were identified using second derivatives of the FTIR absorption spectroscopy. Second derivative analysis normalized and resolved the original spectra and led to the identification of smaller, overlapping bands. Both relative and absolute content of lipids were determined using the integrated band area. M. contortum exhibited higher accumulation of lipids than the other two species. The integrated band area of the vibrations from saturated (SFA) and unsaturated lipids (UFA) enabled quantification of fatty acids. The percentage of SFA and UFA was determined using GC, FTIR and Raman spectroscopy. From the spectral data, the order of increasing concentration of SFA among the three microalgal species was M. contortum > Chlamydomonas sp. >Pseudomuriella sp. The spectral results on fatty acids were consistent with the separation of lipids by gas chromatography. The results emphasized the significance of FTIR and Raman spectroscopic methods in monitoring the biomolecular transitions and rapid quantification of lipids, without the need for extraction of lipids.


Assuntos
Clorófitas , Lipídeos , Microalgas , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Biocombustíveis/análise , Clorófitas/química , Clorófitas/metabolismo , Ácidos Graxos/análise , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Lipídeos/análise , Lipídeos/química , Microalgas/química , Microalgas/metabolismo
16.
Arch Biochem Biophys ; 680: 108235, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31877265

RESUMO

Chlamydomonas reinhardtii is the best known unicellular green alga model which has long been used to investigate all kinds of cellular processes, including starch metabolism. Here we identified and characterized a novel enzyme, ChlreSEX4, orthologous to glucan phosphatase SEX4 from Arabidopsis thaliana, that is capable of binding and dephosphorylating amylopectin in vitro. We also reported that cysteine 224 and tryptophan 305 residues are critical for enzyme catalysis and substrate binding. Furthermore, we verified that ChlreSEX4 gene is expressed in vivo and that glucan phosphatase activity is measurable in Chlamydomonas protein extracts. In view of the results presented, we suggest ChlreSEX4 as a functional phosphoglucan phosphatase from C. reinhardtii. Our data obtained so far contribute to understanding the phosphoglucan phosphatases evolutionary process in the green lineage and their role in starch reversible phosphorylation. In addition, this allows to position Chlamydomonas as a potential tool to obtain starches with different degrees of phosphorylation for industrial or biotechnological purposes.


Assuntos
Chlamydomonas reinhardtii/metabolismo , Clorófitas/metabolismo , Glucanos/metabolismo , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Amilopectina/metabolismo , Chlamydomonas reinhardtii/química , Clorófitas/química , Glucanos/química , Modelos Moleculares , Fosforilação , Proteínas de Plantas/química , Especificidade por Substrato
17.
Am J Chin Med ; 47(8): 1853-1868, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31786945

RESUMO

Skin is the outer tissue layer and is a barrier protecting the body from various external stresses. The fresh water green edible algae Prasiola japonica has antiviral, antimicrobial, and anti-inflammatory properties; however, few studies of its effects on skin-protection have been reported. In this study, Prasiola japonica ethanol extract (Pj-EE) was prepared, and its skin-protective properties were investigated in skin keratinocytes. Pj-EE inhibited ROS production in UVB-irradiated HaCaT cells without cytotoxicity. Pj-EE also suppressed the apoptotic death of UVB-irradiated HaCaT cells by decreasing the generation of apoptotic bodies and the proteolytic activation of apoptosis caspase-3, -8, and -9. Moreover, Pj-EE downregulated the mRNA expression of the inflammatory gene cyclooxygenase-2 (COX-2), the pro-inflammatory cytokine genes interleukin (IL)-1ß, IL-8, IL-6, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ, and the tissue remodeling genes matrix metalloproteinase (MMP)-1, -2, -3, and -9. The Pj-EE-induced anti-inflammatory effect was mediated by suppressing the activation of nuclear factor-kappa B (NF-κB) signaling pathway in the UVB-irradiated HaCaT cells. Taken together, these results suggest that Pj-EE exerts skin-protective effects through anti-oxidant, anti-apoptotic, and anti-inflammatory activities in skin keratinocytes.


Assuntos
Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Clorófitas/química , Queratinócitos/efeitos dos fármacos , Queratinócitos/efeitos da radiação , Extratos Vegetais/farmacologia , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Humanos , Interferon gama/genética , Interferon gama/imunologia , Queratinócitos/citologia , Queratinócitos/imunologia , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/imunologia , NF-kappa B/genética , NF-kappa B/imunologia , Substâncias Protetoras/farmacologia , Pele/citologia , Pele/imunologia , Raios Ultravioleta
18.
Mar Drugs ; 17(12)2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31801243

RESUMO

Aquaculture expansion is limited by the negative environmental impact of the waste and the need for alternative sources in the diet of reared fish. In this framework, for the first time, the survival rates, biomass gain, and fatty acid profiles of the polychaete Sabella spallanzanii and the macroalga Chaetomorpha linum, reared/cultivated as bioremediators in an integrated multitrophic aquaculture system (IMTA), were evaluated for their potential reuse applications. Results showed that these organisms represent a natural source of omega-3 and omega-6. On account of the overall results and the high biomass obtained as by-products, a preliminary study was performed employing both S. spallanzanii and C. linum as new dietary ingredients to feed different sized Dicentrarchus labrax. Fish survival rate, biomass growth, and specific growth rate were determined resulting in no significant differences between control and treated fishes. Histological analyses showed no alterations of the stomach tunica mucosa and submucosa in treated fishes. The eco-friendly approaches applied in the here-realized IMTA system could guarantee the achievement of sustainable by-products represented by the bioremediators S. spallanzanii and C. linum, as well as their reliability as a natural source of compounds beneficial to fish and human health.


Assuntos
Clorófitas/química , Dieta , Poliquetos/química , Animais , Aquicultura , Biomassa , Ácidos Graxos/isolamento & purificação , Ácidos Graxos Ômega-3/isolamento & purificação , Ácidos Graxos Ômega-6/isolamento & purificação , Humanos
19.
Stem Cell Res Ther ; 10(1): 392, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847882

RESUMO

BACKGROUND: Chondrogenesis represents a highly dynamic cellular process that leads to the establishment of various types of cartilage. However, when stress-related injuries occur, a rapid and efficient regeneration of the tissues is necessary to maintain cartilage integrity. Mesenchymal stem cells (MSCs) are known to exhibit high capacity for self-renewal and pluripotency effects, and thus play a pivotal role in the repair and regeneration of damaged cartilage. On the other hand, the influence of certain pathological conditions such as metabolic disorders on MSCs can seriously impair their regenerative properties and thus reduce their therapeutic potential. OBJECTIVES: In this investigation, we attempted to improve and potentiate the in vitro chondrogenic ability of adipose-derived mesenchymal stromal stem cells (ASCs) isolated from horses suffering from metabolic syndrome. METHODS: Cultured cells in chondrogenic-inductive medium supplemented with Cladophora glomerata methanolic extract were experimented for expression of the main genes and microRNAs involved in the differentiation process using RT-PCR, for their morphological changes through confocal and scanning electron microscopy and for their physiological homeostasis. RESULTS: The different added concentrations of C. glomerata extract to the basic chondrogenic inductive culture medium promoted the proliferation of equine metabolic syndrome ASCs (ASCsEMS) and resulted in chondrogenic phenotype differentiation and higher mRNA expression of collagen type II, aggrecan, cartilage oligomeric matrix protein, and Sox9 among others. The results reveal an obvious inhibitory effect of hypertrophy and a strong repression of miR-145-5p, miR-146-3p, and miR-34a and miR-449a largely involved in cartilage degradation. Treated cells additionally exhibited significant reduced apoptosis and oxidative stress, as well as promoted viability and mitochondrial potentiation. CONCLUSION: Chondrogenesis in EqASCsEMS was found to be prominent after chondrogenic induction in conditions containing C. glomerata extract, suggesting that the macroalgae could be considered for the enhancement of ASC cultures and their reparative properties.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Clorófitas/química , Condrogênese/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Síndrome Metabólica/patologia , Extratos Vegetais/farmacologia , Agrecanas/genética , Agrecanas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Clorófitas/metabolismo , Condrócitos/citologia , Condrócitos/metabolismo , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Cavalos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Síndrome Metabólica/metabolismo , MicroRNAs/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/fisiologia , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo
20.
Molecules ; 24(22)2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31717936

RESUMO

Haematococcus pluvialis is known to be a natural source of antioxidants for numerous applications. In this study, an oleoresin rich in carotenoids extracted by supercritical CO2 treatment of H. pluvialis was extensively characterized for its antioxidant capacity. Carotenoid content, fatty acid profile, total phenol content, antioxidant capacity, and viscosity of the oleoresin were determined with the aim of ascertaining the potential of the oleoresin in terms of its antioxidant content for food applications. The oleoresin contained 96.22 mg/g of total astaxanthin (which includes free astaxanthin and astaxanthin esters) and mostly included unsaturated fatty acids (~78% of total fatty acids). High total phenol content and ferric reducing antioxidant potential indicated high antioxidant capacity, but oxygen radical absorbance capacity was lower compared to the oleoresin samples obtained from other species. The oleoresin was a non-Newtonian fluid since it had shear-thinning (pseudoplastic) and shear-thickening (dilatant) flow. Therefore, the H. pluvialis oleoresin is a potential alternative in developing functional ingredients for designing healthy food products. To the best of our knowledge, this is the first study that has reported an extensive characterization of the antioxidant properties of a microalgal oleoresin obtained by means of supercritical CO2 fluid extraction.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Clorófitas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Carotenoides/química , Carotenoides/farmacologia , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Ácidos Graxos , Hidrólise , Fenóis/química , Fenóis/farmacologia , Temperamento , Viscosidade
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