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1.
Food Chem ; 334: 127562, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32707368

RESUMO

Brown seaweeds are traditionally used as food in Asian countries, and they are a valuable source of bioactive compounds. Herein, a novel high-throughput methodological approach was developed for the tracing of compounds with radical scavenging and antimicrobial activities in Saccharina japonica and Undaria pinnatifida methanol extracts. The seaweed metabolites were separated by a novel high-performance thin-layer chromatography method, the bioactive bands were identified by bioautography assays. The bioactive compounds were characterized with ultra-high-performance liquid chromatography coupled with linear trap quadrupole tandem mass spectrometry. Stearidonic, eicosapentaenoic, and arachidonic acids were identified as major components having radical scavenging and antimicrobial activities. The suggested method provides a fast identification and quantification of bioactive compounds in multicomponent biological samples.


Assuntos
Anti-Infecciosos/análise , Cromatografia em Camada Delgada/métodos , Alga Marinha/química , Espectrometria de Massas em Tandem/métodos , Anti-Infecciosos/química , Ácidos Araquidônicos/análise , Ácidos Araquidônicos/farmacologia , Ácido Eicosapentaenoico/análise , Ácido Eicosapentaenoico/farmacologia , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-3/farmacologia , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Ensaios de Triagem em Larga Escala/métodos , Laminaria/química , Laminaria/metabolismo , Alga Marinha/metabolismo , Undaria/química , Undaria/metabolismo
2.
Int J Mol Sci ; 21(1)2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31906436

RESUMO

CRY-DASH, a new cryptochrome blue light receptor, can repair damaged DNA and regulate secondary metabolism and development of fungus. However, its role in regulation during the growth of Saccharina japonica is still unclear. After cloning the full-length of CRY-DASH from S. japonica (sjCRY-DASH), we deduced that its open reading frame was 1779 bp long and encoded 592 amino acids. sjCRY-DASH transcription was rapidly upregulated within 30 min in response to blue light and exhibited 24 h periodicity with different photoperiods. Moreover, sjCRY-DASH maintained the same periodicity in suitable growth temperature, suggesting a close relationship between this periodicity and circadian rhythm regulation. Novel-m3234-5p, which was targeted to sjCRY-DASH, decreased with increasing sjCRY-DASH transcription, acting as a negative modulator of sjCRY-DASH. Six long non-coding RNAs classified as long intergenic non-coding RNAs (lincRNAs) exhibited co-expression with sjCRY-DASH. A miRNA sjCRY DASH lincRNA network was consequently identified. By predicting the endogenous competing mRNAs of novel-m3234-5p, we found that sjCRY-DASH indirectly participated in the regulation of DNA damage repair, protein synthesis and processing, and actin transport. In conclusion, our results revealed that non-coding RNAs participate in the regulation of sjCRY-DASH, which played vital roles in the growth and early development of S. japonica.


Assuntos
Criptocromos/metabolismo , Laminaria/genética , Laminaria/metabolismo , RNA Longo não Codificante/metabolismo , Ritmo Circadiano/genética , Ritmo Circadiano/efeitos da radiação , Análise por Conglomerados , Criptocromos/genética , Reparo do DNA/genética , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/efeitos da radiação , Laminaria/crescimento & desenvolvimento , Laminaria/efeitos da radiação , Luz , Fotoperíodo , RNA Longo não Codificante/genética , RNA Mensageiro/metabolismo , Temperatura
3.
Carbohydr Polym ; 225: 115211, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521267

RESUMO

Fucoidan from Laminaria japonica is a kind of sulfate polysaccharide with high molecular weight (MW) and broad bioactivities. This study was performed to investigate the relationship between MW and whitening activity of fucoidan and to exploit a novel functional ingredient for whitening cosmetics. High sulfate content fucoidan was enzymic degraded by Flavobacterium RC2-3 produced fucoidanase. Two hours were enough for the enzyme degradation to achieve degraded fucoidan with favorable tyrosinase inhibitory ability. The whitening activity of different MW fucoidan fractions were evaluated by their tyrosinase inhibitory ability, antioxidant activity and cellular melanogenesis inhibitory ability. Results showed that in the MW range above 5 kDa, the smaller MW of fucoidan were related to the better whitening activity. The fucoidan fraction with the MW between 5-10 kDa, presented the best tyrosinase inhibitory activity (62.0%), antioxidant activity (48.3%) and excellent anti-melanogenesis ability in B16 cells, which could be applied as the whitening factor in cosmetics development.


Assuntos
Clareadores , Laminaria/metabolismo , Polissacarídeos , Preparações Clareadoras de Pele , Animais , Antioxidantes , Clareadores/química , Clareadores/farmacologia , Linhagem Celular Tumoral , Peso Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Polissacarídeos/química , Polissacarídeos/farmacologia , Preparações Clareadoras de Pele/química , Preparações Clareadoras de Pele/farmacologia , Sulfatos/metabolismo
4.
Carbohydr Polym ; 225: 115224, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521294

RESUMO

Laminaran, a ß-(1→3)-glucan extracted from Laminaria digitata, is a known elicitor of plant defenses, but provides only low level of disease control in vineyard trials. In this context, laminaran was partly hydrophobized by grafting from 1.6 to 7.6 lauryl chains to the native saccharidic chain and the impact of sulfation of the hydrophobized glucans was studied. The activity of the different synthetized laminaran derivatives as antimicrobial agents against Plasmopara viticola, the causal agent of grape downy mildew, and as elicitors of defense reactions in planta, was evaluated. Our results showed that acylation imparts an antimicrobial activity to laminaran which is related to the degree of acylation, AL3, with 7.6 lauryl chains, being the most effective derivative. Sulfation of the acylated laminarans did not further increase the antimicrobial activity. Our results also demonstrated that the efficacy of AL3 against Plasmopara viticola was most likely due to the direct antimicrobial activity of the lauryl chains rather than to an elicitation of plant defenses.


Assuntos
Resistência à Doença , Glucanos/farmacologia , Oomicetos/metabolismo , Doenças das Plantas/microbiologia , Vitis , Anti-Infecciosos/farmacologia , Laminaria/metabolismo , Vitis/metabolismo , Vitis/microbiologia
5.
Mar Drugs ; 17(7)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340503

RESUMO

Prostaglandins (PGs) are lipid mediators belonging to the eicosanoid family. PGs were first discovered in mammals where they are key players in a great variety of physiological and pathological processes, for instance muscle and blood vessel tone regulation, inflammation, signaling, hemostasis, reproduction, and sleep-wake regulation. These molecules have successively been discovered in lower organisms, including marine invertebrates in which they play similar roles to those in mammals, being involved in the control of oogenesis and spermatogenesis, ion transport, and defense. Prostaglandins have also been found in some marine macroalgae of the genera Gracilaria and Laminaria and very recently the PGs pathway has been identified for the first time in some species of marine microalgae. In this review we report on the occurrence of prostaglandins in the marine environment and discuss the anti-inflammatory role of these molecules.


Assuntos
Anti-Inflamatórios/metabolismo , Organismos Aquáticos/química , Prostaglandinas/metabolismo , Animais , Antozoários/química , Antozoários/metabolismo , Anti-Inflamatórios/química , Organismos Aquáticos/metabolismo , Gracilaria/química , Gracilaria/metabolismo , Laminaria/química , Laminaria/metabolismo , Microalgas/química , Microalgas/metabolismo , Prostaglandinas/química , Tromboxanos/química , Tromboxanos/metabolismo
6.
Food Chem ; 295: 101-109, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174738

RESUMO

Edible seaweeds are highly consumed food with a rich chlorophyll profile. Although seaweeds are mainly cooked ingested, the influence of cooking on the chlorophyll bioaccessibility remains unknown. In this research, cooked Nori, Sea Lettuce and Kombu were subjected to an in vitro digestion and following micellarization investigations. The processing of red seaweed does not affect the chlorophyll recovery, while cooking green and brown seaweeds implies an important increase in chlorophyll recovery after in vitro digestion. In this line, while cooking affects negatively the micellarization rate of chlorophyll derivatives in Nori and Kombu, it does not modify the micellarization in Sea Lettuce. Generally, the chlorophyll bioaccessibility of microwaved seaweeds is always higher than that of boiled ones. However, cooking improves the chlorophyll bioaccessibility in brown seaweeds, while decreases in red seaweeds. In conclusion, the characteristics of food matrix are the determinant factor on the chlorophyll bioaccessibility of cooked seaweeds.


Assuntos
Clorofila/análise , Culinária , Laminaria/química , Porphyra/química , Ulva/química , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Laminaria/metabolismo , Micro-Ondas , Porphyra/metabolismo , Espectrofotometria , Ulva/metabolismo , alfa-Amilases/metabolismo
7.
Int J Mol Sci ; 20(10)2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31096691

RESUMO

Blue light (BL) plays an important role in regulation of the growth and development of aquatic plants and land plants. Aureochrome (AUREO), the recent BL photoreceptor identified in photosynthetic stramenopile algae, is involved in the photomorphogenesis and early development of Saccharina japonica porophytes (kelp). However the factors that interact with the SjAUREO under BL conditions specifically are not clear. Here in our study, three high quality cDNA libraries with CFU over 5 × 106 and a recombination rate of 100% were constructed respectively through white light (WL), BL and darkness (DK) treatments to the juvenile sporophytes. Based on the constructed cDNA libraries, the interactors of SjAUREO were screened and analyzed. There are eighty-four genes encoding the sixteen predicted proteins from the BL cDNA library, sixty-eight genes encoding eighteen predicted proteins from the DK cDNA library, and seventy-four genes encoding nineteen proteins from the WL cDNA library. All the predicted proteins are presumed to interact with SjAUREO when co-expressed with SjAUREO seperately. The 40S ribosomal protein S6 (RPS6), which only exists in the BL treated cDNA library except for two other libraries, and which is essential for cell proliferation and is involved in cell cycle progression, was selected for detailed analysis. We showed that its transcription was up-regulated by BL, and was highly transcribed in the basal blade (meristem region) of juvenile sporophytes but less in the distal part. Taken together, our results indicated that RPS6 was highly involved in BL-mediated kelp cellular division and photomorphogenesis by interacting with SjAUREO.


Assuntos
Laminaria/metabolismo , Laminaria/efeitos da radiação , Luz , Proteína S6 Ribossômica/metabolismo , Proteína S6 Ribossômica/efeitos da radiação , Proteínas Ribossômicas/metabolismo , Proteínas Ribossômicas/efeitos da radiação , Proliferação de Células , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Biblioteca Gênica , Genes de Plantas/genética , Laminaria/genética , Células Fotorreceptoras/metabolismo , Células Fotorreceptoras/efeitos da radiação , Fotossíntese , Proteínas de Plantas/genética , Proteínas Ribossômicas/genética , Regulação para Cima/efeitos da radiação
8.
Metallomics ; 11(4): 756-764, 2019 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-30834917

RESUMO

Brown algae include the strongest accumulators of iodine known among living systems. This paper reviews the current state of bioinorganic research in the field, focusing on the models Laminaria digitata, Macrocystis pyrifera and Ectocarpus siliculosus, and covering uptake and efflux, localization and biological significance of storage, as well as marine and atmospheric chemistry of iodine.


Assuntos
Iodo/metabolismo , Laminaria/metabolismo , Macrocystis/metabolismo , Feófitas/metabolismo , Transporte Biológico , Imunidade Inata , Iodo/imunologia , Laminaria/imunologia , Macrocystis/imunologia , Estresse Oxidativo , Feófitas/imunologia
9.
Bioresour Technol ; 281: 84-89, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30802819

RESUMO

Alginate oligosaccharides (AOS) showed various biological activities. Traditional protocol for producing AOS was a multiple-step and high-pollution procedure. In this study, a rapid and efficient AOS producing method was developed directly from Laminaria japonica. Natural sun-dried L. japonica with a feed ratio of 1:7 (w/v) was pretreated using cellulase with a dry weight of 3%, for releasing the fermentable sugars (8.5 g/L glucose and 15.2 g/L mannitol). Then, the engineered yeast Yarrowia lipolytica strain with alginate lyase activity was grown using an algae-based medium. After fermentation for 72 h, glucose and mannitol were completely consumed, and 71.8 mM AOS was extracted from the fermentation supernatant. The degree of polymerization (DP) was ranging from 2 to 3. The recovery yield of AOS was about 91.7%. The purity of the extracted AOS was 92.6%. Overall, our work provided new insights for the development of green biotechnologies for oligosaccharide production from seaweed.


Assuntos
Fermentação , Laminaria/metabolismo , Oligossacarídeos/metabolismo , Alginatos/metabolismo , Hidrólise , Alga Marinha/metabolismo , Yarrowia/genética , Yarrowia/metabolismo
10.
Bioresour Technol ; 276: 361-368, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30658265

RESUMO

This work investigated the thermophilic (55 °C) co-digestion performance both in batch and continuous mode operation. The biochemical methane potentials of L. digitata and cattle manure were 308 ±â€¯24 and 203 ±â€¯33 mL CH4/g VS, respectively. The optimum co-digestion feedstock ratio was found to be 80% macroalgae: 20% manure on a volatile solids basis, which produced 290 ±â€¯19 mL CH4/g VS under long-term and stable continuous operation at an organic loading rate of 2 g VS/L/d and hydraulic retention time of 15 days. Simulations of the batch and continuous experiments were, for the first time, carried out using an integrated anaerobic bioconversion model without structural modifications. Close fits between measured and simulated data provided mutual confirmation of experimental reliability and model robustness, and provided new perspectives for the use of the software tool.


Assuntos
Laminaria/metabolismo , Esterco , Animais , Reatores Biológicos , Bovinos , Metano/biossíntese , Reprodutibilidade dos Testes
11.
Sci Rep ; 8(1): 17180, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30464260

RESUMO

Marine plant communities such as kelp forests produce significant amounts of detritus, most of which is exported to areas where it can constitute an important trophic subsidy or potentially be sequestered in marine sediments. Knowing the vertical transport speed of detrital particles is critical to understanding the potential magnitude and spatial extent of these linkages. We measured sinking speeds for Laminaria hyperborea detritus ranging from whole plants to small fragments and sea urchin faecal pellets, capturing the entire range of particulate organic matter produced by kelp forests. Under typical current conditions, we determined that this organic material can be transported 10 s of m to 10 s of km. We show how the conversion of kelp fragments to sea urchin faeces, one of the most pervasive processes in kelp forests globally, increases the dispersal potential of detritus by 1 to 2 orders of magnitude. Kelp detritus sinking speeds were also faster than equivalent phytoplankton, highlighting its potential for rapid delivery of carbon to deep areas. Our findings support arguments for a significant contribution from kelp forests to subsidizing deep sea communities and the global carbon sink.


Assuntos
Organismos Aquáticos/metabolismo , Organismos Aquáticos/fisiologia , Carbono/análise , Laminaria/metabolismo , Material Particulado/análise , Ouriços-do-Mar/metabolismo , Água do Mar/química , Animais , Ecossistema , Cadeia Alimentar
12.
J Biosci Bioeng ; 126(6): 710-714, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29910187

RESUMO

This study aimed to investigate the characteristics of hydrogen production by mixed cultures using Laminaria japonica hydrolysates. The hydrolysates of L. japonica were prepared by pretreatment methods, including heat (100°C or 121°C) and acid (HCl or H2SO4) pretreatments. The mixed cultures could produce hydrogen using L. japonica as a substrate, with the highest cumulative hydrogen production of 825 ± 14 mL/L from HCl-pretreated L. japonica. High-throughput sequencing of the 16S rRNA gene revealed that the microbial community in the hydrolysate of HCl-pretreated L. japonica was the most diverse among all the samples, with a Shannon diversity index of 5.253. The mixed culture from HCl-pretreated L. japonica and those from heat-pretreated (100°C and 121°C) L. japonica occupied different regions in a principal component analysis (PCA) plot. The dominant population in the hydrolysate of HCl-pretreated L. japonica was represented by hydrogen-producing bacteria, Clostridium spp. and Bacillus spp. The results suggested that L. japonica was an optimal feedstock for hydrogen production. The acid (HCl) pretreatment method could effectively enhance the hydrogen production from L. japonica.


Assuntos
Bactérias , Sedimentos Geológicos , Hidrogênio/metabolismo , Laminaria/citologia , Laminaria/metabolismo , Bactérias/citologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Fermentação , Sedimentos Geológicos/química , Ácido Clorídrico/química , Ácido Clorídrico/farmacologia , Microbiota/efeitos dos fármacos , Microbiota/fisiologia , RNA Ribossômico 16S , Alga Marinha/citologia , Alga Marinha/metabolismo
13.
Glob Chang Biol ; 24(9): 4386-4398, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29862600

RESUMO

Global climate change is affecting carbon cycling by driving changes in primary productivity and rates of carbon fixation, release and storage within Earth's vegetated systems. There is, however, limited understanding of how carbon flow between donor and recipient habitats will respond to climatic changes. Macroalgal-dominated habitats, such as kelp forests, are gaining recognition as important carbon donors within coastal carbon cycles, yet rates of carbon assimilation and transfer through these habitats are poorly resolved. Here, we investigated the likely impacts of ocean warming on coastal carbon cycling by quantifying rates of carbon assimilation and transfer in Laminaria hyperborea kelp forests-one of the most extensive coastal vegetated habitat types in the NE Atlantic-along a latitudinal temperature gradient. Kelp forests within warm climatic regimes assimilated, on average, more than three times less carbon and donated less than half the amount of particulate carbon compared to those from cold regimes. These patterns were not related to variability in other environmental parameters. Across their wider geographical distribution, plants exhibited reduced sizes toward their warm-water equatorward range edge, further suggesting that carbon flow is reduced under warmer climates. Overall, we estimated that Laminaria hyperborea forests stored ~11.49 Tg C in living biomass and released particulate carbon at a rate of ~5.71 Tg C year-1 . This estimated flow of carbon was markedly higher than reported values for most other marine and terrestrial vegetated habitat types in Europe. Together, our observations suggest that continued warming will diminish the amount of carbon that is assimilated and transported through temperate kelp forests in NE Atlantic, with potential consequences for the coastal carbon cycle. Our findings underline the need to consider climate-driven changes in the capacity of ecosystems to fix and donate carbon when assessing the impacts of climate change on carbon cycling.


Assuntos
Ciclo do Carbono , Carbono/metabolismo , Mudança Climática , Temperatura Alta , Laminaria/metabolismo , Biomassa , Temperatura Baixa , Inglaterra , Escócia , Água do Mar/análise , País de Gales
14.
J Phycol ; 54(1): 114-125, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29130494

RESUMO

The biogeochemistry of iodine in temperate coastal ecosystems is largely mediated by macroalgae, which act as a major biological sink and source of iodine. Their capacity to accumulate, retain and release iodine has been associated with abiotic and biotic stressors, but quantitative information is limited. We evaluated the seasonal iodine retention capacity of eleven macroalgal species belonging to different systematic groups, collected from two sites in Ireland. Iodine accumulation and retention were then further quantified in Fucus vesiculosus and Laminaria digitata in relation to I- concentrations in seawater and temperature. In general, iodine contents were ~101 -102  µmol · (g dw)-1 for Laminariales, 100 -101  µmol · (g dw)-1 for Fucales, 10-1 -100  µmol · (g dw)-1 for Rhodophyta, and 10-1  µmol · (g dw)-1 for Chlorophyta. Typically, algal iodine contents were above average in winter and below average in summer. Iodine accumulation in F. vesiculosus and L. digitata depended on I- availability and followed the Michaelis-Menten kinetic. The ratio of maximum accumulation rate to half accumulation coefficient (ρmax : Kt ) was 2.4 times higher for F. vesiculosus than for L. digitata, suggesting that F. vesiculosus was more efficient in iodine accumulation. Both species exhibited a temperature-dependent net loss of iodine, and only an exposure to sufficient external I- concentrations compensated for this loss. This study revealed that both environmental (e.g., I- in seawater, temperature) and organismal (e.g., the status of the iodine storage pool) variables determine retention and variability in iodine in temperate seaweeds.


Assuntos
Fucus/metabolismo , Iodo/metabolismo , Laminaria/metabolismo , Alga Marinha/metabolismo , Irlanda , Cinética , Feófitas/metabolismo , Rodófitas/metabolismo , Especificidade da Espécie , Ulva/metabolismo
15.
J Sci Food Agric ; 98(10): 3644-3650, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29250785

RESUMO

BACKGROUND: Phlorotannins (PhTs) are marine tannins consisting of phloroglucinol subunits connected via carbon-carbon and ether linkages. These have non-covalent protein binding properties and are, therefore, expected to be beneficial in protecting protein from hydrolysis during ruminal fermentation. In this study, the effectiveness of a methanolic PhTs extract from Laminaria digitata (10, 20, 40, 50, 75 and 100 g kg-1 tannin-free grass silage, with or without addition of polyethylene glycol (PEG), was investigated in vitro on protection of dietary protein and reduction of methane (CH4 ) in ruminal fluid. RESULTS: Addition of PhTs had linear (P < 0.0001) and quadratic (P = 0.0003) effects on gas and CH4 production, respectively. Optimal dosage of PhTs was 40 g kg-1 as at this point CH4 decreased (P < 0.0001) from 24.5 to 15.2 mL g-1 organic matter (OM), without affecting gas production (P = 0.3115) and total volatile fatty acids (P = 1.000). Ammonia trended (P = 0.0903) to decrease from 0.49 to 0.39 mmol g-1 OM, indicating protection of protein. Addition of PEG inhibited the effect of tannins at all dosage levels, and none of the fermentation parameters differed from the control. CONCLUSION: PhTs effectively protected protein from fermentation and reduced ruminal methanogenesis. © 2017 Society of Chemical Industry.


Assuntos
Laminaria/metabolismo , Metano/metabolismo , Proteínas de Plantas/metabolismo , Rúmen/metabolismo , Taninos/química , Amônia/metabolismo , Ração Animal/análise , Animais , Bovinos , Digestão , Ácidos Graxos Voláteis/metabolismo , Fermentação , Laminaria/química , Proteólise , Silagem/análise
16.
J Agric Food Chem ; 65(44): 9595-9602, 2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-29058916

RESUMO

Marine phlorotannins (PhT) from Laminaria digitata might protect feed proteins from ruminal digestion by formation of insoluble non-covalent tannin-protein complexes at rumen pH (6-7). Formation and disintegration of PhT-protein complexes was studied with ß-casein (random coil) and bovine serum albumin (BSA, globular) at various pH. PhT had similar binding affinity for ß-casein and BSA as pentagalloyl glucose, as studied by fluorescence quenching. The affinity of PhT for both proteins was independent of pH (3.0, 6.0, and 8.0). In the presence of PhT, the pH range for precipitation of tannin-protein complexes widened to 0.5-1.5 pH units around the isoelectric point (pI) of the protein. Complete protein resolubilization from insoluble PhT-protein complexes was achieved at pH 7 and 2 for ß-casein and BSA, respectively. It was demonstrated that PhT modulate the solubility of proteins at neutral pH and that resolubilization of PhT-protein complexes at pH deviating from pI is mainly governed by the charge state of the protein.


Assuntos
Caseínas/química , Laminaria/química , Extratos Vegetais/química , Rúmen/metabolismo , Alga Marinha/química , Soroalbumina Bovina/química , Taninos/química , Animais , Caseínas/metabolismo , Bovinos , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Laminaria/metabolismo , Extratos Vegetais/metabolismo , Rúmen/química , Alga Marinha/metabolismo , Soroalbumina Bovina/metabolismo , Solubilidade , Taninos/metabolismo
17.
Cryobiology ; 79: 50-55, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28941986

RESUMO

In this study, water-soluble Laminaria japonica polysaccharide3 (LJP-P3) was investigated for the cryoprotective effects on bull sperm. Five concentrations of LJP-P3 with 0.1, 1, 10, 50 and 100 mmol/L were added into the extenders of bull semen, respectively, and the effects on quality of sperm after freezing-thawing were assessed. The results showed that the kinematic parameters of bull sperm including linear motile sperm (LM), curvilinear line velocity (VCL) value, straight line velocity (VSL) and velocity of the average path (VAP) were greater in the extenders containing LJP-P3 (P<0.05). In comparison to those of other treatments and control group the extenders containing 1.0, 10.0 and 50.0 mmol/L of LJP-P3 led to higher percentage of mitochondrial activity and sperm membrane integrity(P<0.05), and the acrosome integrity of bull cryopreservation sperm were significantly improved in all treatment groups. Moreover, the higher GSH-Px, SOD and CAT levels in bull cryopreservation sperm were favored from the extenders of 10.0, 50.0 and 100.0 mmol/L LJP-P3 added (P<0.05) compared with other treatments and control group. In addition, the results of artificial insemination showed that both the pregnancy rate and the number of calving were higher in the group of semen containing 10 mmol/L of LJP-P3 than that of control group (P <0.05). In summary, LJP-P3 exhibited a greater cryoprotective effect to bull sperm and the most suitable concentration of LJP-P3 is 10.0 mmol/L.


Assuntos
Antioxidantes/farmacologia , Criopreservação/métodos , Crioprotetores/farmacologia , Polissacarídeos/farmacologia , Preservação do Sêmen/métodos , Motilidade Espermática/efeitos dos fármacos , Acrossomo/efeitos dos fármacos , Animais , Catalase/metabolismo , Bovinos , Feminino , Congelamento , Glutationa Peroxidase/metabolismo , Inseminação Artificial , Laminaria/metabolismo , Masculino , Mitocôndrias/efeitos dos fármacos , Gravidez , Sêmen/efeitos dos fármacos , Análise do Sêmen , Espermatozoides/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Água/metabolismo
18.
PLoS One ; 12(7): e0180760, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28704453

RESUMO

Historically Saccharina spp. beds occurred along the west coast of Hokkaido, an oligotrophic area, and were commercially exploited. Currently extensive commercial Saccharina spp. beds do not form due to nutrient limitations. Here, we postulate that nutrients assimilated by paleo-Saccharina spp. beds may have been derived from spawning herrings (Clupea pallasii) acting as organisms that formed a vector from their feeding grounds (Okhotsk Sea and Pacific Ocean) to their spawning area (west coast of Hokkaido, Japan Sea). To test this hypothesis we examined stable nitrogen isotope ratios (δ15N) of 100- to 135-year-old Saccharina specimens preserved at the Herbarium (Hokkaido University Museum). δ15N values of the paleo-Saccharina specimens collected from this region were in the range of 10‰, which is significantly higher than the current 3-7‰ in freshly sampled Saccharina spp. This high δ15N indicates that spawning herring (Clupea pallasii) had potentially been a significant source of dissolved inorganic nitrogen (DIN) absorbed by Saccharina, acting as an organism forming a vector for transporting nutrients from eutrophic to oligotrophic coastal ecosystems. Our findings support the hypothesis of so-called "herring-derived nutrients."


Assuntos
Laminaria/química , Isótopos de Nitrogênio/análise , Animais , Peixes/metabolismo , Cadeia Alimentar , Laminaria/metabolismo , Água do Mar/química
19.
Food Chem Toxicol ; 104: 95-108, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28161465

RESUMO

The presence of contaminants in aquatic ecosystems can cause serious problems to the environment and marine organisms. This study aims to evaluate the phycoremediation capacity of macroalgae Laminaria digitata for pesticides (diflubenzuron and lindane) and toxic elements (cadmium and copper) in seawater in the presence or absence of mussels. The photosynthetic activity was monitored in the macroalgae to assess its "physiological status". The results showed that the presence of algae decreased diflubenzuron concentration in mussels by 70% after 120 h of exposure. Additionally, this macroalgae was efficient to reduce lindane, Cu and Cd in seawater; even though it not was able to reduce these contaminants in mussels. The studied pollutants did not affect the physiological status of macroalgae. This study reveals that the application of phycoremediation with macroalgae can be an useful and effective mitigation strategy to remove/decrease contaminant levels from the aquatic environment.


Assuntos
Cádmio/metabolismo , Cobre/metabolismo , Diflubenzuron/metabolismo , Recuperação e Remediação Ambiental/métodos , Hexaclorocicloexano/metabolismo , Laminaria/metabolismo , Alga Marinha/metabolismo , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Cádmio/análise , Cobre/análise , Diflubenzuron/análise , Poluentes Químicos da Água/análise
20.
Bioresour Technol ; 218: 224-31, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27371795

RESUMO

Aquatic micro-algae can be used as feedstocks for gaseous biofuel production via biological fermentation. However, micro-algae usually have low C/N ratios, which are not advantageous for fermentation. In this study, carbon-rich macro-algae (Laminaria digitata) mixed with nitrogen-rich micro-algae (Chlorella pyrenoidosa and Nannochloropsis oceanica) were used to maintain a suitable C/N ratio of 20 for a two-stage process combining hydrogen and methane fermentation. Co-fermentation of L. digitata and micro-algae facilitated hydrolysis and acidogenesis, resulting in hydrogen yields of 94.5-97.0mL/gVS; these values were 15.5-18.5% higher than mono-fermentation using L. digitata. Through the second stage of methane co-fermentation, a large portion of energy remaining in the hydrogenogenic effluents was recovered in the form of biomethane. The two-stage batch co-fermentation markedly increased the energy conversion efficiencies (ECEs) from 4.6-6.6% during the hydrogen fermentation to 57.0-70.9% in the combined hydrogen and methane production.


Assuntos
Biocombustíveis , Reatores Biológicos , Hidrogênio/metabolismo , Metano/metabolismo , Microalgas/metabolismo , Biomassa , Carbono/análise , Carbono/química , Carbono/metabolismo , Chlorella/microbiologia , Conservação de Recursos Energéticos , Fermentação , Hidrogênio/análise , Hidrogênio/química , Laminaria/metabolismo , Metano/análise , Metano/química , Nitrogênio/análise , Nitrogênio/química , Nitrogênio/metabolismo , Energia Renovável
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