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1.
Bioresour Technol ; 319: 124163, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33254444

RESUMO

Hydrothermal liquefaction (HTL) of Gracilaria corticata (GC) macroalgae was studied over a series of nickel-iron-layered double oxides (NiFe-LDO) supported on activated bio-char catalysts at 280 °C and different solvents medium. Maximum bio-oil yield (56.2 wt%) was found with 5%Ga/NiFe-LDO/AC catalyst at 280 °C under ethanol solvent. The catalytic HTL up-gradation decreased the bio-char yield significantly. However the bio-oil quality significantly improved with using the 5%Ga/NiFe-LDO/AC catalyst. Also, improved performance with higher amount of bio-oil and lower amounts of bio-char and gas were achieved, which is due the several reactions happening during the HTL process. Catalytic HTL also revealed that introducing NiFe-LDO nanosheets into the activated char could result in NiFe-LDO/AC catalysts of higher surface area and increased active sites. Being impregnated by 5%Ga, catalysts with improved acid sites and thereby, advanced deoxygenation and aromatization activities were achieved. Hence Ga/NiFe-LDO/AC could be considered as a promising catalyst HTL bio-oil upgrading.


Assuntos
Gracilaria , Alga Marinha , Biocombustíveis , Biomassa , Óleos Vegetais , Polifenóis , Temperatura , Água
2.
Ecotoxicol Environ Saf ; 206: 111183, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32890922

RESUMO

Seaweed is an inherently important entity in marine ecosystems. It is not only consumed by aquatic animals but also improves environmental quality in the mariculture. Seaweed is also part of the diet of human beings. The purpose of the present study was to evaluate the antagonism of selenium (Se)-enriched Gracilaria lemaneiformis against heavy metals, specifically, the potential of dietary Se-enriched Gracilaria to protect against heavy metal toxicity in rabbitfish (Siganus oramin). Growth rate, heavy metal (Se, Cd, Pb, Cu, Zn and Cr) concentrations, malondialdehyde (MDA), metallothionein (MT), and the activity of the antioxidants, glutathione peroxidase (GPX), catalase (CAT) and superoxide dismutase (SOD) were all assessed. The results showed that the total organic and inorganic Se concentration for the 250 mg L-1 Se-enriched Gracilaria was significantly higher than those of the 50 and 10 mg L-1 treatments after 3 days of enrichment. The mean total Se concentrations in Gracilaria were 42.5 µg g-1 in the 250 mg L-1 treatment, 13.5 µg g-1 in the 50 mg L-1 treatment and 2.5 µg g-1 in the 10 mg L-1 treatment, respectively. Organic Se accounts for 80-82% of total Se in Se-enriched Gracilaria. The Se concentration of rabbitfish fed Se-enriched Gracilaria was significantly higher than control. Furthermore, Se increased Cu and Zn absorption, and enhanced MT generation, and improved GPX, CAT, and SOD antioxidant activity, and decreased MDA concentrations and lipid peroxidation levels, all antagonistic to Cd, Pb and Cr. The effects of Se-enriched Gracilaria on waterborne Cd, Pb and Cr-induced toxicity occurred via both enzymatic and non-enzymatic antioxidative mechanisms in rabbitfish. Selenium had synergistic effects on Zn and Cu in rabbitfish. For the 50 mg L-1 Se-enriched Gracilaria treatment, the Se, Cu, Zn, and antagonistic Cd, Pb, Cr, and the antioxidant enzymes CAT, SOD, GPX activities, and MT concentrations in rabbitfish were higher than that with the 250 mg L-1 and 10 mg L-1 Se-enriched Gracilaria treatments. The 50 mg L-1 Se treatment of Gracilaria was deemed to be the optimum concentration to promote growth of rabbitfish. Therefore, the obtained results suggest Se-enriched Gracilaria can antagonize heavy metal toxicity, and is an advisable Se supplement to improve the edible safety of cultured animals.


Assuntos
Antioxidantes/metabolismo , Peixes/metabolismo , Gracilaria/química , Metais Pesados/toxicidade , Alga Marinha/química , Selênio/análise , Animais , Catalase/metabolismo , Ecossistema , Peixes/crescimento & desenvolvimento , Cadeia Alimentar , Glutationa Peroxidase/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Metalotioneína/metabolismo , Metais Pesados/análise , Metais Pesados/metabolismo , Oxirredução , Selênio/metabolismo , Superóxido Dismutase/metabolismo
3.
Food Chem ; 330: 127324, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32569938

RESUMO

Enzymes currently used in cheesemaking have various drawbacks, and there is a continual need to find new coagulants. This study describes the extraction and biochemical characterization of two proteases from the red alga Gracilaria edulis. The proteases were extracted with phosphate buffer and partially purified by ammonium sulphate precipitation and dialysis. The enzymes exhibited optimum caseinolytic activity at 60 °C and a pH range of 6-8. They showed a high ratio of milk-clotting over caseinolytic activity, indicating they had an excellent milk-clotting ability. The proteases were confirmed to be serine protease and metalloprotease with molecular weight (MW) of 44 and 108 kDa. They exhibited high hydrolytic activity on κ-caseins, cleaving κ-casein at four main sites, one of which being the same as that of calf rennet, which is the first reported for an algal protease. The findings demonstrated that the proteases could potentially be used as a milk coagulant in cheesemaking.


Assuntos
Caseínas/metabolismo , Gracilaria/enzimologia , Peptídeo Hidrolases/isolamento & purificação , Peptídeo Hidrolases/metabolismo , Alga Marinha/enzimologia , Sulfato de Amônio , Animais , Caseínas/química , Fracionamento Químico , Quimosina/metabolismo , Eletroforese em Gel de Poliacrilamida , Gracilaria/química , Concentração de Íons de Hidrogênio , Hidrólise , Leite/química , Leite/metabolismo , Peso Molecular , Peptídeo Hidrolases/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Alga Marinha/química , Serina Proteases/química , Serina Proteases/isolamento & purificação , Serina Proteases/metabolismo , Espectrometria de Massas em Tandem , Temperatura
4.
Food Chem ; 321: 126688, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32247888

RESUMO

The extraction of phycobiliprotein (PBP) pigments from red algae Gracilaria gracilis was optimized using maceration, ultrasound-assisted extraction (ultrasonic water bath and ultrasonic probe), high pressure-assisted extraction, and freeze-thaw. The experimental conditions, namely homogenization time (t1), buffer concentration (C), treatment time (t2), biomass: buffer ratio (R), and pressure (P), were optimized using Response Surface Methodology (RSM). The yield of phycoerythrin (PE) extracted, determined spectroscopically, was used as the response variable. Maceration was the most efficient extraction method yielding 3.6 mg PE/g biomass under the optimal conditions (t1 = t2 = 10 min; C = 0.1 M; R = 1:50). Scanning Electron Microscopy (SEM) analysis of the biomass before and after the cell disruption treatments revealed a more efficient cell wall rupture with maceration.


Assuntos
Corantes de Alimentos/química , Gracilaria/química , Ficobiliproteínas/química , Biomassa , Pigmentação
5.
J Microbiol Biotechnol ; 30(6): 930-936, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32238769

RESUMO

The red seaweed Gracilaria verrucosa has been used for the production of bioethanol. Pretreatment for monosaccharide production was carried out with 12% (w/v) G. verrucosa slurry and 500 mM HNO3 at 121°C for 90 min. Enzymatic hydrolysis was performed with a mixture of commercial enzymes (Cellic C-Tec 2 and Celluclast 1.5 L; 16 U/ml) at 50°C and 150 rpm for 48 h. G. verrucosa was composed of 66.9% carbohydrates. In this study, 61.0 g/L monosaccharides were obtained from 120.0 g dw/l G. verrucosa. The fermentation inhibitors such as hydroxymethylfurfural (HMF), levulinic acid, and formic acid were produced during pretreatment. Activated carbon was used to remove HMF. Wildtype and adaptively evolved Saccharomyces cerevisiae, Candida lusitaniae, and Kluyveromyces marxianus were used for fermentation to evaluate ethanol production.


Assuntos
Candida/metabolismo , Etanol/análise , Gracilaria/metabolismo , Kluyveromyces/metabolismo , Monossacarídeos/biossíntese , Saccharomyces cerevisiae/metabolismo , Fermentação , Galactose/química , Hidrólise , Alga Marinha/metabolismo
6.
PLoS One ; 15(4): e0231337, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32275732

RESUMO

Exotic species may increase or decrease native biodiversity. However, effects of exotic species are often mixed; and indirect pathways and compensatory changes can mask effects. Context-specific assessments of the indirect impacts of exotic species are also needed across multiple spatial scales. Agarophyton vermiculophyllum (previously Gracilaria vermiculophylla), an exotic, invasive macroalga, has established throughout the western hemisphere with reported positive or neutral impacts on biodiversity. Shorebirds are an important group for conservation in areas invaded by A. vermiculophyllum. We assess the impacts of this invader on shorebirds by measuring behavior and habitat selection at spatial scales ranging from algal patches to the entire study region. Birds were considered either flexible-foragers that used diverse foraging techniques, or specialized-foragers that employed fewer, more specialized foraging techniques. Responses were scale dependent, with patterns varying between spatial scales, and between behavior and habitat selection. However, a general pattern of habitat selection emerged wherein flexible-foraging shorebirds preferred A. vermiculophyllum habitat, and for specialized-foragers, habitat selection of A. vermiculophyllum was mixed. Meanwhile, flexible-foraging birds tended to neutrally use or avoid uninvaded habitat, and specialized-foraging birds mostly preferred uninvaded habitat. Shorebird behavioral response was less clear; with flexible-foragers spending less time on bare sediment than expected, the only significant response. Shorebird response to A. vermiculophyllum differed by foraging mode; likely because flexible, opportunistic species more readily use invaded habitat. Increases in A. vermiculophyllum could result in functional homogenization if the bare habitat preferred by specialized-foragers is reduced too greatly. We hypothesize the effect of scale is driven by differences among tidal flats. Thus, tidal flat properties such as sediment grain size and microtopography would determine whether foraging from A. vermiculophyllum was optimal for a shorebird. Specialization and spatial scale are important when assessing the biodiversity conservation impacts of invasive A. vermiculophyllum.


Assuntos
Biodiversidade , Aves/fisiologia , Comportamento Alimentar , Gracilaria/fisiologia , Animais , Cadeia Alimentar , Movimento
7.
J Environ Manage ; 263: 110376, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32174523

RESUMO

Low recycling rates of rare earth elements (REEs) are a consequence of inefficient, expensive and/or contaminating methods currently available for their extraction from solid wastes or from liquid wastes such as acid mine drainage or industrial wastewaters. The search for sustainable recovery alternatives was the motivation for this study. For the first time, the capabilities of 6 living macroalgae (Ulva lactuca, Ulva intestinalis, Fucus spiralis, Fucus vesiculosus, Osmundea pinnatifida and Gracilaria sp.) to remove REEs (Y, La, Ce, Pr, Nd, Eu, Gd, Tb, Dy) from laboratory-prepared seawater spiked with REE solutions were evaluated. The assays lasted 72 h with REEs concentrations ranging from 10 to 500 µg L-1. The link between REEs uptake and algal metabolism, surface morphology and chemistry were addressed. Kinetics varied among the species, although most of the removal occurred in the first 24 h, with no equilibrium being reached. Lack of mortality reveal that the algae maintained their metabolism in the presence of the REEs. Green alga U. lactuca stood out as the only capable of efficiently removing at least 60% of all elements, reaching removals up to 90% in some cases. The high bioconcentration factors, derived from mass balance analysis (c.a. 2500) support that the REEs enriched algal biomass (up to 1295 µg g-1) may constitute an effective and environmentally friendly alternative source of REEs to conventional extraction from ores.


Assuntos
Gracilaria , Metais Terras Raras , Alga Marinha , Ulva , Poluição da Água
8.
Mar Drugs ; 18(2)2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-32012662

RESUMO

Previously, we reported that the ethanol extract from red seaweed Gracilaria fisheri effectively decreased biofilm formation of Vibrio harveyi. In this study, the anti-biofilm active compounds in the ethanol extract were isolated and their structures identified. The anti-biofilm fractionation assay for minimum inhibitory concentration (MIC) produced two fractions which possessed maximal inhibitory activities toward the biofilm formation of V. harveyi strains 1114 and BAA 1116. Following chromatographic separation of the bioactive fractions, two pure compounds were isolated, and their structures were elucidated using FTIR, NMR, and HR-TOF-MS. The compounds were N-benzyl cinnamamide and α-resorcylic acid. The in vitro activity assay demonstrated that both compounds inhibited the biofilm formation of V. harveyi and possessed the anti-quorum sensing activity by interfering with the bioluminescence of the bacteria. However, the N-benzyl cinnamamide was more potent than α-resorcylic acid with a 10-fold lesser MIC. The present study reveals the beneficial property of the N-benzyl cinnamamide from the ethanol extract as a lead anti-microbial drug against V. harveyi.


Assuntos
Antibacterianos/farmacologia , Cinamatos/farmacologia , Gracilaria , Percepção de Quorum/efeitos dos fármacos , Hidroxibenzoatos , Resorcinóis , Alga Marinha/efeitos dos fármacos , Vibrio/efeitos dos fármacos , Vibrio/fisiologia
9.
Carbohydr Polym ; 234: 115894, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32070514

RESUMO

The fermentation behaviour of sulfated polysaccharides (GLP) and their agaro-oligosaccharides (GLO) derived from Gracilaria lemaneiformis were examined. During in vitro fermentation, GLP and GLO increased the concentrations of short chain fatty acids (SCFAs) and modulated the composition and diversity of gut microorganisms compared with control groups. GLP increased the abundance of Bacteroidetes and decreased the abundance of Firmicutes, while GLO increased the abundance of Firmicutes and Actinobacteria. Moreover, the abundances of potential pathogenic bacteria were reduced. Molecular weight and intrinsic viscosity of GLP decreased significantly from 2.15 × 105 to 1.22 × 105 Da, 374.45-113.91 mL/g, respectively. Furthermore, GLP was degraded into smaller degree of polymerization of oligosaccharides, with no significant change observed in GLO. Overall, this study revealed GLP and GLO could be beneficial for gastrointestinal tract by producing SCFAs and modulating intestinal microbes, indicating GLP and GLO are potentially sources of prebiotics in functional foods.


Assuntos
Fezes/microbiologia , Fermentação , Microbioma Gastrointestinal , Gracilaria/metabolismo , Polissacarídeos/metabolismo , Sulfatos/metabolismo , Humanos
10.
Carbohydr Polym ; 232: 115790, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952598

RESUMO

In this study, an eco-friendly extraction method was explored to obtain high sulfate content agar and repair the deficiency of enzymatic extraction by taking full advantage of H2O2. The sulfate content of EHA (H2O2-assisted enzymatic extracted agar) reached 3.56 %, which is significantly higher than that of traditional alkali-extracted agar (AA, 1.8 %). Moreover, EHA exhibited lower viscosity (9.4 cP), which improved 26.6 % and 14 % of filtration and gel dehydration rates than EA (enzymatic extracted agar), respectively. Additionally, the physicochemical properties of the agars were evaluated and compared. Among these agars, EHA showed some favorable properties, such as high yield (16.08 %) and low dissolution temperature (88.9 °C). The surface of algae became smoother after treatment with H2O2 due to effective degradation of cellulose. Besides, mass spectrometry analysis revealed that EHA preserved a great amount of sulfate, while thermogravimetric analysis suggested that the thermal stability of EA and EHA both decreased.


Assuntos
Ágar/isolamento & purificação , Gracilaria/química , Peróxido de Hidrogênio/química , Sulfatos/isolamento & purificação , Ágar/química , Tamanho da Partícula , Sulfatos/química , Propriedades de Superfície , Viscosidade
11.
Phytochemistry ; 172: 112259, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31954358

RESUMO

Three macrolides bearing the carbon framework of oxabicyclo[21.3.1]heptacosa-ene-diones (A and B) and oxabicyclo[19.3.1]pentacosa-ene-dione (C) were isolated and characterised from the organic extract of the intertidal red seaweed Gracilaria salicornia (family Gracilariaceae), which were named as salicornolides A-C. These natural macrolides were conformationally pre-organised ring structure providing diverse functionalities, and their potential bioactive properties led to the development of pharmacophores with anti-inflammatory properties. The 21-membered pyran-enclosed salicornolide B displayed greater cyclooxygenase-2 (IC50 COX-2 1.13 mM) inhibitory activity than those exhibited by the 21-membered aryl salicornolide A and 19-membered salicornolide C (IC50 COX-2-1.2 mM). The attenuating potential of the studied compounds against pro-inflammatory enzyme, 5-lipoxygenase (IC50 LOX < 1.5 mM) was significantly greater than that displayed by the non-steroidal anti-inflammatory ibuprofen (IC50 4.5 mM), whereas the selectivity indices exhibited by salicornolides against cyclooxygenase-2 was significantly higher (1.18-1.41, P < 0.05) when compared to that of ibuprofen (SI 0.43) attributing the greater selectivity profile of the former towards inducible pro-inflammatory mediators than the latter. The minimal binding energy of salicornolide B (-9.64 kcal mol-1), a greater number of hydrogen-bonds and lesser inhibitory constant (Ki 85.15 nM) might be responsible for effective binding towards 5-lipoxygenase, and that could attribute its greater anti-inflammation potential than those displayed by other compounds. The putative biosynthetic cascade initiated by malonate-acyl carrier protein unambiguously confirmed the structural attributions of the titled macrocyclic lactones. The undescribed salicornolides A-C from seaweed Gracilaria salicornia attenuating pro-inflammatory 5-lipoxygense might be considered as prospective natural anti-inflammatory leads for pharmaceutical applications.


Assuntos
Chenopodiaceae , Gracilaria , Anti-Inflamatórios , Anti-Inflamatórios não Esteroides , Antioxidantes , Ciclo-Oxigenase 2 , Inibidores de Lipoxigenase , Estudos Prospectivos
12.
Carbohydr Polym ; 230: 115567, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887913

RESUMO

Sulfated oligosaccharide of Gracilaria lemaneiformis (GLSO) was prepared from sulfated polysaccharides which possessed antiallergic activity by degradation with high temperature and pressure combined with vitamin C treatment. The present study demonstrated that GLSO could attenuate food anaphylaxis, and inhibit the production of immunoglobulin E, histamine, and related cytokines in both prevention and therapy ovalbumin-induced mice model. Additionally, the gut microbiota analysis revealed that GLSO markedly rescued OVA-induced changes in the Firmicutes to Bacteroidetes ratio. Following flow cytometry, GLSO was found to suppress the subpopulation of T helper 2 and B cells, and significantly up-regulate regulatory T cells (Tregs) differentiation. Furthermore, GLSO-mediated immunosuppression could be verified by co-culturing Tregs sorted from GLSO-treated mice and CD4+ T cells or mast cells. In a word, GLSO attenuated food anaphylaxis through the regulation of gut microbiota and induction of immunosuppression. GLSO had the potential to be used as a nutrient component against food allergy.


Assuntos
Antialérgicos/farmacologia , Hipersensibilidade Alimentar/tratamento farmacológico , Gracilaria/química , Oligossacarídeos/farmacologia , Substâncias Protetoras/farmacologia , Animais , Antialérgicos/química , Citocinas/metabolismo , Modelos Animais de Doenças , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/prevenção & controle , Humanos , Imunossupressão , Mastócitos/efeitos dos fármacos , Camundongos , Oligossacarídeos/química , Oligossacarídeos/imunologia , Substâncias Protetoras/química , Sulfatos/química , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia
13.
Int J Syst Evol Microbiol ; 70(1): 100-104, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31535968

RESUMO

A Gram-stain-negative, aerobic and curved-rod-shaped bacterium, designated QM202T, was isolated from red algae (Gracilaria blodgettii). Cells of strain QM202T were 0.2-0.3 µm wide and 1.0-2.5 µm long, catalase-negative and oxidase-positive. The strain exhibited an agar-degrading activity. It was motile by means of a single polar flagellum. Optimal growth occurred at 28-30 °C, pH 7.0-7.5 and in the presence of 2.0-3.0 % (w/v) NaCl. The DNA G+C content was 41.4 mol%. The isoprenoid quinone was identified as Q-8. Phophatidylethanolamine and phosphatidylglycerol were the predominant phospholipids. The dominant fatty acids were C18:1ω7c, C16:0 and C16:1ω7c and/or iso-C15:0 2-OH. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain QM202T belonged to the genus Marinomonas. The closest described neighbour in terms of 16S rRNA gene sequence identity was Marinomonas blandensis MED121T (95.5 %). The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness indicated that strain QM202T can be considered to represent a novel species, Marinomonas agarivorans sp. nov. The type strain is QM202T (=KCTC 52475T=MCCC 1H00145T).


Assuntos
Gracilaria/microbiologia , Marinomonas/classificação , Filogenia , Ágar , Alteromonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Marinomonas/isolamento & purificação , Oceanos e Mares , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
14.
Nat Prod Res ; 34(10): 1409-1416, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-30518261

RESUMO

Phytochemical investigation on the biologically active compounds of seaweed Gracilaria salicornia {(C. Agardh) E.Y. Dawson} (family Gracilariaceae) guided to the separation of a previously unreported abeo-labdane class of diterpenoid. The compound was characterized as methyl-16(13→14)-abeo-7-labdene-(12-oxo) carboxylate by extensive spectroscopic experiments, and comparison with the related compounds. The studied compound registered significantly greater activities against pro-inflammatory 5-lipoxygenase (IC50 0.86 mg/mL) than that exhibited by non-steroidal anti-inflammatory agent ibuprofen (IC50 0.92 mg/mL, P < 0.05). Likewise, this compound exhibited comparable radical quenching (1, 1-diphenyl-2-picryl-hydrazil) activity (IC50 0.66 mg/mL) as standard antioxidant agent α-tocopherol (IC50 0.62 mg/mL).


Assuntos
Antioxidantes/farmacologia , Diterpenos/química , Gracilaria/química , Inibidores de Lipoxigenase/farmacologia , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/química , Araquidonato 5-Lipoxigenase/metabolismo , Diterpenos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Inibidores de Lipoxigenase/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Alga Marinha/química
15.
Water Environ Res ; 92(6): 880-898, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31813162

RESUMO

The present work proposes the synthesis of robust biochar from Gracilaria Rhodophyta red weeds for sequential removal of Al(III) and fluoride from wastewater. The sorption experiments have been modeled by preliminary optimization of operational parameters using 24 factorial statistical modeling. The model has estimated an optimum sequential synergetic removal of 44.5 mg/g of Al(III) and 2.1 mg/g of fluoride onto the biochar. FESEM, BET, XRD, EDX, and FTIR established the potentiality of biochar toward synergetic sorption of Al(III) and fluoride. The thermodynamic analysis projected that the adsorption is physisorption in nature. The adsorption of Al(III) and fluoride follows the Langmuir and Freundlich isotherm models, respectively, and the kinetic analysis established the pseudo-second-order deposition of Al(III) and fluoride ions. The synthesized adsorbent is regenerative enough and could achieve synergetic removal of Al(III) and fluoride ions from industrial- and groundwater-contaminated water bodies. PRACTITIONER POINTS: Biochar from seaweeds is explored in the sequential removal of Al(III) and F- ions. Statistical model is developed for % adsorption and tested for reliability by ANOVA. GRBC sorbed 44.5 and 2.1 mg/g of Al(III) and F- ions, respectively, at optimum levels. FESEM, EDX, XRD, and FTIR characterization confirm the potentiality of the GRBC. GRBC sorbed ⁓90% of Al(III) and F- ions from wastewater and is regenerative.


Assuntos
Gracilaria , Poluentes Químicos da Água , Purificação da Água , Adsorção , Alumínio , Carvão Vegetal , Fluoretos , Cinética , Reprodutibilidade dos Testes
16.
Food Funct ; 11(1): 1049-1062, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31819936

RESUMO

Polysaccharides from Gracilaria lemaneiformis (GLPs) were shown to reduce high fat diet (HFD)-induced metabolic syndrome (MS), but its high molecular weight (MW) causes lots of barriers to its application in foods as a functional ingredient. In this study, oligosaccharides derived from GLPs (D-GLPs) were prepared, and its effect on HFD-induced MS and inflammation was evaluated in mice. It revealed that D-GLPs reduced fat accumulation, lipid disorders and inflammation in HFD-fed mice accompanied by an improvement of the gut microbiota. D-GLPs reversed HFD-induced gut microbiota dysbiosis characterized by the increased ratio of Bacteroidetes to Firmicutes and the abundance of the Bacteroidales. Spearman correlation analysis showed that some members of the Bacteroidales were positively correlated with reduced fat accumulation, inflammation and lipid disorders. Compared to GLPs, D-GLPs had a better inhibition effect on MS-related parameters, which may be attributed to higher abundance of some Bacteroidales members owing to their prioritization strategy to D-GLPs. The anti-obesity effect was transmissible through fecal transfer from D-GLPs-fed mice to HFD-fed mice, implying that the effect was associated with the gut microbiota. It indicated that D-GLPs can be used as a potential prebiotic agent to MS therapy.


Assuntos
Microbioma Gastrointestinal , Inflamação/terapia , Síndrome Metabólica/terapia , Oligossacarídeos/farmacologia , Animais , Bactérias/classificação , Dieta Hiperlipídica/efeitos adversos , Fezes , Gracilaria/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Prebióticos
17.
Chemosphere ; 245: 125636, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31869668

RESUMO

Seaweeds are good bio-monitors of heavy metals pollution in coastal seawater. In the present study, the potential bioremediation effects of cultivated Gracilaria lemaneiformis on heavy metals in Nan'ao coastal sediment from a typical mariculture zone, South China were evaluated. Sediment samples were collected from five different zones (Gracilaria cultivation zone, G; Fish culture zone, F; Shellfish culture zone, S; Transition zone, T; Control zone, C) from December 2014 to July 2015. The concentrations of Cd, Pb, Cu, and Zn in the sediments were significantly different among the various types of mariculture areas. The concentrations varied widely: Cd (0.04-1.02) µg g-1; Cu (1.19-37.70) µg g-1; Pb (8.45-74.45) µg g-1; Zn (36.80-201.24) µg g-1. The lowest heavy metal concentrations in the sediment were occurred at Gracilaria cultivation zone, while higher concentrations occurred at control zones and fish culture zones. The pollution load index, principal components and cluster analysis showed that heavy metal concentrations were the highest at fish culture zone, while the concentrations were the lowest at Gracilaria cultivation zone, and Gracilaria cultivation affects the heavy metals in the sediments. Gracilaria had strong adsorption capacities for heavy metals from seawater, showing the highest heavy metal Bioconcentration Factors in May (higher seaweed biomass period). Consequently, the results suggested that Gracilaria cultivation influences the heavy metal concentrations in sediments from the typical coastal mariculture zone. Gracilaria cultivation has the potential to bioremediate heavy metals in the coastal sediments. Therefore, Gracilaria cultivation can add environmental advantages and ecological values to coastal mariculture zones.


Assuntos
Aquicultura , Biodegradação Ambiental , Gracilaria/metabolismo , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , China , Ecologia , Monitoramento Ambiental/métodos , Peixes , Sedimentos Geológicos/análise , Metais Pesados/análise , Metais Pesados/toxicidade , Rodófitas , Alimentos Marinhos/análise , Água do Mar , Alga Marinha , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
18.
Mar Drugs ; 17(12)2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31835446

RESUMO

Active polysaccharides as safe and natural polymers against bacterial diarrhea have been reconsidered as an alternative to antibiotics. This work investigated the inhibiting effect of depolymerized sulfated galactans from Eucheuma serra and Gracilaria verrucosa on the growth and adhesion of diarrheagenic enterotoxigenic Escherichia coli (ETEC) K88. Results showed that the sulfated polysaccharides with molecular weight distribution ≤20.0 kDa exhibited antibacterial activity against ETEC K88. A structure-activity study revealed that the anti-ETEC K88 activity of sulfated polysaccharides is strictly determined by their molecular weight distribution, sulfate group content, and monosaccharide composition. In addition, the promoted nucleic acid release and the fluorescence quenching of membrane proteins were observed after the treatment with selected polysaccharides. Scanning electron microscopy further confirmed that the depolymerized sulfated galactans can effectively inhibit ETEC K88 adhesion. In conclusion, depolymerized sulfated galactans exhibited an inhibitory effect on the growth and adhesion of ETEC K88.


Assuntos
Antibacterianos/farmacologia , Escherichia coli Enterotoxigênica/efeitos dos fármacos , Galactanos/farmacologia , Rodófitas/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Diarreia/tratamento farmacológico , Galactanos/química , Galactanos/isolamento & purificação , Gracilaria/química , Microscopia Eletrônica de Varredura , Peso Molecular , Polímeros/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Relação Estrutura-Atividade , Sulfatos/química
19.
Sci Rep ; 9(1): 16134, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31695116

RESUMO

European seabass (Dicentrarchus labrax) production is often hampered by bacterial infections such as photobacteriosis caused by Photobacterium damselae subsp. piscicida (Phdp). Since diet can impact fish immunity, this work investigated the effect of dietary supplementation of 5% Gracilaria sp. aqueous extract (GRA) on seabass antioxidant capacity and resistance against Phdp. After infection, mortality was delayed in fish fed GRA, which also revealed increased lysozyme activity levels, as well as decreased lipid peroxidation, suggesting higher antioxidant capacity than in fish fed a control diet. Dietary GRA induced a down-regulation of hepatic stress-responsive heat shock proteins (grp-78, grp-170, grp-94, grp-75), while bacterial infection caused a down-regulation in antioxidant genes (prdx4 and mn-sod). Diet and infection interaction down-regulated the transcription levels of genes associated with oxidative stress response (prdx5 and gpx4) in liver. In head-kidney, GRA led to an up-regulation of genes associated with inflammation (il34, ccr9, cd33) and a down-regulation of genes related to cytokine signalling (mif, il1b, defb, a2m, myd88). Additionally, bacterial infection up-regulated immunoglobulins production (IgMs) and down-regulated the transcription of the antimicrobial peptide leap2 in head kidney. Overall, we found that GRA supplementation modulated seabass resistance to Phdp infection.


Assuntos
Ração Animal , Bass/fisiologia , Suplementos Nutricionais , Doenças dos Peixes/prevenção & controle , Gracilaria , Infecções por Bactérias Gram-Negativas/veterinária , Photobacterium , Animais , Peptídeos Catiônicos Antimicrobianos/biossíntese , Peptídeos Catiônicos Antimicrobianos/genética , Aquicultura , Bass/sangue , Bass/imunologia , Glicemia/análise , Citocinas/biossíntese , Citocinas/genética , Resistência à Doença , Doenças dos Peixes/dietoterapia , Doenças dos Peixes/imunologia , Doenças dos Peixes/metabolismo , Regulação da Expressão Gênica , Infecções por Bactérias Gram-Negativas/dietoterapia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Rim Cefálico/metabolismo , Proteínas de Choque Térmico/biossíntese , Proteínas de Choque Térmico/genética , Imunoglobulina M/biossíntese , Peroxidação de Lipídeos , Fígado/metabolismo , Muramidase/sangue , Triglicerídeos/sangue
20.
ScientificWorldJournal ; 2019: 2565692, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31780875

RESUMO

Currently, the demand of Pleurotus HK-37 (oyster mushroom) in Tanzania is growing rapidly due to the increasing of awareness on its nutrition, health, and economic benefits. Despite the increasing demand, the availability of strains of Pleurotus HK-37 species is still a challenge due to high cost of tissue culture technology. The high cost of importing agar seems to be among the factors for this failure. This study aimed at investigating the performance of low-cost agar from local Gracilaria salicornia on tissue culture of Pleurotus HK-37. Local extracted agars with different gel strengths ranging between 100, 200, 300, 400, and 500 g/cm2 were used to make PDA media. The average mycelia growth rate (mm/day) ranged between 9.87 ± 1.44 and 14.9 ± 0.85 mm/day. Low-cost agar shows quite similar performance as that of standard agar on active growth of Pleurotus HK-37 mycelia. All PDA plates appeared white and feathery and showed to grow in a circular mode (radial extension). Mycelia growth on standard agar PDA took 5 days while on extracted local agar PDA took 5 to 7 days to fully colonize the plate at 27 ± 2°C. The present study shows that the production cost can be reduced by ∼35-78% by using local agar.


Assuntos
Ágar/química , Gracilaria/química , Pleurotus/crescimento & desenvolvimento , Ágar/economia , Ágar/farmacologia , Agricultura/economia , Agricultura/métodos , Custos e Análise de Custo , Pleurotus/efeitos dos fármacos
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