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1.
J R Soc Interface ; 21(211): 20230676, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38378137

RESUMO

Marine life is populated by a huge diversity of organisms with an incredible range of colour. While structural colour mechanisms and functions are usually well studied in marine animal species, there is a huge knowledge gap regarding the marine macroalgae (red, green and brown seaweeds) that have structural coloration and the biological significance of this phenomenon in these photosynthetic organisms. Here we show that structural colour in the gametophyte life history phase of the red alga Chondrus crispus plays an important role as a photoprotective mechanism in synergy with the other pigments present. In particular, we have demonstrated that blue structural coloration attenuates the more energetic light while simultaneously favouring green and red light harvesting through the external antennae (phycobilisomes) which possess an intensity-dependent photoprotection mechanism. These insights into the relationship between structural colour and photosynthetic light management further our understanding of the mechanisms involved.


Assuntos
Chondrus , Animais , Cor , Células Germinativas Vegetais , Fotossíntese , 60439
2.
Int J Biol Macromol ; 260(Pt 1): 129433, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38232891

RESUMO

The immunomodulatory properties of the polysaccharides (carrageenan, xylan) from Chondrus crispus (CC), Ahnfeltiopsis devoniensis (AD), Sarcodiotheca gaudichaudii (SG) and Palmaria palmata (PP) algal species were studied. Using RAW264.7 macrophages, we investigated the proliferation and migration capacity of different extracts along with their immunomodulatory activities, including nitric oxide (NO) production, phagocytosis, and secretion of pro-inflammatory cytokines. Polysaccharides from C. crispus and S. gaudichaudii effectively mitigated inflammation and improved scratch-wound healing. Polysaccharide fractions extracted under cold conditions (25 °C), including CC-1A, SG-1A and SG-1B stimulated cell proliferation, while fractions extracted under hot conditions (95 °C), including CC-3A, CC-2B and A. devoniensis (AD-3A), inhibited cell proliferation after 48 h. Furthermore, RAW264.7 cells treated with the fractions CC-3A, AD-1A, and SG-2A significantly reduced LPS-stimulated NO secretion over 24 h. Phagocytosis was significantly improved by treatment with C. crispus (CC-2B, CC-3B) and A. devoniensis (AD-3A) fractions. RAW264.7 cells treated with the CC-2A and SG-1A fractions showed elevated TGF-ß1 expression without affecting TNF-α expression at 24 h. Polysaccharide fractions of A. devoniensis (ι/κ hybrid carrageenan; AD-2A, AD-3A) showed the highest anti-coagulation activity. CC-2A and SG-1A fractions enhanced various bioactivities, suggesting they are candidates for skin-health applications. The carrageenan fractions (CC-3A: λ-, µ-carrageenan, SG-2A: ν-, ι-carrageenan) tested herein showed great potential for developing anti-inflammatory and upscaled skin-health applications.


Assuntos
Chondrus , 60578 , Rodófitas , Alga Marinha , Carragenina/farmacologia , Xilanos , Polissacarídeos/farmacologia , Alga Marinha/metabolismo , Anti-Inflamatórios/farmacologia , Anticoagulantes
3.
Mar Drugs ; 22(1)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38248672

RESUMO

Macroalgae, particularly red seaweeds, have attracted significant attention due to their economic and health benefits. Chondrus, a red algae genus, despite its economic importance, seems to be undervalued. Among all its species, Chondrus crispus has been meticulously documented for its biological properties, and little is known about other species. No comprehensive review of the biological properties of this genus has been acknowledged. Thus, this review aimed to summarize the available information on the chemical constituents and biological properties of a few selected species, including Chondrus crispus, Chondrus ocellatus, Mazzaella canaliculata, and Chondrus armatus. We compiled and discovered that the genus is offering most of the important health-promoting benefits evidenced from in vitro and in vivo studies focused on antimicrobial, immunomodulation, neuroprotection, anti-atopic, anti-inflammatory, anti-viral, anti-diabetic, cytoprotective, antioxidant, anti-coagulation, nephroprotective, anti-tumor, and anti-venom activity, which speaks about the potential of this genus. Data on clinical studies are limited. Further, around 105 chemical constituents have been reported from Chondrus spp. Given its significance, further investigation is warranted, in the form of meticulously planned cell, animal, and clinical studies that concentrate on novel health-enhancing endeavors, in order to unveil the full potential of this genus. The review also outlines challenges and future directions.


Assuntos
Chondrus , Hipersensibilidade Imediata , Alga Marinha , Animais , Antioxidantes/farmacologia , Antivenenos
4.
Aquat Toxicol ; 261: 106609, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37315338

RESUMO

Plastics are the most abundant marine litter in the world's oceans and can be degraded into micro-plastics. These emerging pollutants negatively affect marine organisms, but little is known on the effects on macroalgae. In this study, we investigated the effects of micro-plastics on two species of red algae: Grateloupia turuturu and Chondrus sp. Grateloupia turuturu has a slippery surface while Chondrus sp. has a rough surface. Different surface characteristics of these macroalgae may affect adherence of micro-plastics. Both species were exposed to 5 different concentrations (0, 20, 200, 2000 and 20,000 ng/L) of polystyrene microspheres. Adherence capacity, accumulating micro-plastics on the surface was higher for Chondrus sp. than G. turuturu. Chondrus sp. at 20,000 ng/L only showed a decrease in growth rate and photosynthesis activity, and an increase of reactive oxygen species (ROS). However, G. turuturu was not significantly affected by micro-plastics at all tested concentrations. Shaded light and inhibition of gas flow by adhered micro-plastics may be a reason for the reduction of growth and photosynthesis and production of ROS. Based on this result, the toxic effects of micro-plastics appear to be species specific, dependent on the adherence capacity of macroalgae.


Assuntos
Chondrus , Rodófitas , Alga Marinha , Poluentes Químicos da Água , Plásticos , Microplásticos , Espécies Reativas de Oxigênio , Poluentes Químicos da Água/toxicidade
5.
Mar Drugs ; 20(12)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36547888

RESUMO

The carrageenans isolated from red algae demonstrated a variety of activities from antiviral and immunomodulatory to antitumor. The diverse structure and sulfation profile of carrageenans provide a great landscape for drug development. In this study, we isolated, purified and structurally characterized κo- and λo- oligosaccharides from the marine algae Chondrus armatus. We further examined the tumor suppressive activity of both carrageenans in gastrointestinal cancer models. Thus, using MTT assay, we could demonstrate a pronounced antiproliferative effect of the carrageenans in KYSE-30 and FLO-1 as well as HCT-116 and RKO cell lines with IC50 184~405 µg/mL, while both compounds were less active in non-cancer epithelial cells RPE-1. This effect was stipulated by the inhibition of cell cycle progression in the cancer cells. Specifically, flow cytometry revealed an S phase delay in FLO-1 and HCT-116 cells under κo-carrageenan treatment, while KYSE-30 demonstrated a pronounced G2/M cell cycle delay. In line with this, western blotting revealed a reduction of cell cycle markers CDK2 and E2F2. Interestingly, κo-carrageenan inhibited cell cycle progression of RKO cells in G1 phase. Finally, isolated κo- and λo- carrageenans induced apoptosis on adenocarcinomas, specifically with high apoptosis induction in RKO cells. Overall, our data underline the potential of κo- and λo- carrageenans for colon and esophageal carcinoma drug development.


Assuntos
Chondrus , Neoplasias Gastrointestinais , Rodófitas , Humanos , Carragenina/química , Chondrus/química , Rodófitas/química , Plantas/metabolismo
6.
Mar Drugs ; 20(11)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36355018

RESUMO

Novel personal care products are necessary to cope with the growing market demand for sustainable green products. In this context, this work deals with the formulation and fundamental physicochemical and rheological characterization of different natural personal care products using bioactive fractions from Chondrus crispus red macroalgae extracted under optimized green conditions. Body milks, body oils and shampoos were supplemented with soluble extracts with antioxidant features recovered after hydrothermal (200 °C) and microwave (170 °C)- and ultrasound (80 °C)-assisted extraction of the red macroalgae used as raw material. Formulated products were also compared with those prepared using (±)-α-tocopherol and butylhydroxytoluene standards. Body scrubs were formulated with the remaining solids (<2.25%) after microwave hydrodiffusion and gravidity treatment of the macroalgae. Results indicated that selected extracts provided personal care products with similar or even better physicochemical, color and viscous features than those supplemented with (±)-α-tocopherol or butylhydroxytoluene commercial antioxidants. Rheological profiles indicated that it is possible to develop personal care products with adequate viscous behavior (102−105 mPa s, at 1 s−1), comparable with their synthetic counterparts. To conclude, the addition of antioxidant extracts led to lower apparent viscosity values suggesting an advantage from the skin applicability point of view, jointly with the absence of both the hysteresis phenomenon and water syneresis of the proposed formulations.


Assuntos
Chondrus , Cosméticos , Alga Marinha , Chondrus/química , Antioxidantes , Hidroxitolueno Butilado , alfa-Tocoferol , Alga Marinha/química
7.
J Biol Chem ; 298(12): 102707, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36402445

RESUMO

The carrageenophyte red alga Chondrus crispus produces three family 16 glycoside hydrolases (CcGH16-1, CcGH16-2, and CcGH16-3). Phylogenetically, the red algal GH16 members are closely related to bacterial GH16 homologs from subfamilies 13 and 14, which have characterized marine bacterial ß-carrageenase and ß-porphyranase activities, respectively, yet the functions of these CcGH16 hydrolases have not been determined. Here, we first confirmed the gene locus of the ccgh16-3 gene in the alga to facilitate further investigation. Next, our biochemical characterization of CcGH16-3 revealed an unexpected ß-porphyranase activity, since porphyran is not a known component of the C. crispus extracellular matrix. Kinetic characterization was undertaken on natural porphyran substrate with an experimentally determined molecular weight. We found CcGH16-3 has a pH optimum between 7.5 and 8.0; however, it exhibits reasonably stable activity over a large pH range (pH 7.0-9.0). CcGH16-3 has a KM of 4.0 ± 0.8 µM, a kcat of 79.9 ± 6.9 s-1, and a kcat/KM of 20.1 ± 1.7 µM-1 s-1. We structurally examined fine enzymatic specificity by performing a subsite dissection. CcGH16-3 has a strict requirement for D-galactose and L-galactose-6-sulfate in its -1 and +1 subsites, respectively, whereas the outer subsites are less restrictive. CcGH16-3 is one of a handful of algal enzymes characterized with a specificity for a polysaccharide unknown to be found in their own extracellular matrix. This ß-porphyranase activity in a carrageenophyte red alga may provide defense against red algal pathogens or provide a competitive advantage in niche colonization.


Assuntos
Chondrus , Rodófitas , Chondrus/genética , Rodófitas/genética , Polissacarídeos , Glicosídeo Hidrolases , Biologia
8.
Int J Biol Macromol ; 206: 553-566, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35245577

RESUMO

The integral utilization of sustainable resources with versatile, efficient and cleaner processes is encouraged. Hydrothermal treatment with subcritical water is a chemical free, tunable and rapid technology providing enhanced yield compared to conventional extraction and was explored for the benign by design extraction and depolymerization of carrageenan from Chondrus crispus. Up to 90% of the seaweed was solubilized operating under nonisothermal regime during heating up to 200 °C and 75.5% crude carrageenan yield was attained at 140 °C. Crude carrageenan could not be precipitated by ethanol from the extracts produced at 180 °C and higher temperatures, but ultrafiltration (100 kDa) of the extract obtained at 160 °C provided comparable recovery yields and similar rheological features to those of the ethanol precipitated product. Operation at 140 °C was preferred based on the higher recovery yield of the biopolymer and the whole extract was suitable for the green synthesis of polycrystalline decahedral quasi-spherical gold nanoparticles with a mean size distribution of 8.4 nm and Z potential value of -40.2 mV. Alternatively, the crude carrageen fraction was used for the formulation of printable biopolymer based gels with suitable mechanical properties, including a relevant gel strength enhancement (about 10-fold) when compared with conventional procedures.


Assuntos
Chondrus , Nanopartículas Metálicas , Carragenina/química , Chondrus/química , Etanol , Ouro , Hidrogéis , Extratos Vegetais/química
9.
Food Chem ; 383: 132450, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35182861

RESUMO

Dehydration of the edible seaweed Chondrus crispus was performed by freeze-drying, conventional oven-drying and emerging microwave hydrodiffusion and gravity (MHG). In this work, the drying kinetics and modelling, estimating specific energy consumption and environmental impact of distinct processes were tested. Color and microstructural features of the dried macroalgae were also evaluated, as well as their nutritive characterization, chemical profile and bioactive potential (antioxidant and antimicrobial activities). Moreover, collected liquid phases from both the defrosted and MHG treated samples were also characterized. All methodologies provided solid phases with an adequate final moisture content. MHG significantly reduced the needed time, specific energy consumption and environmental impact, providing C. crispus with intermediate color and histological structure characteristics. Overall, this trend was also defined to tested chemical parameters and bioactivities. MHG provided aqueous extracts with potential bioactive compounds from this red alga, increasing the efficiency of this drying method.


Assuntos
Chondrus , Alga Marinha , Antioxidantes/química , Chondrus/química , Dessecação , Liofilização , Alga Marinha/química , Verduras
10.
J Phycol ; 58(2): 330-342, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35090190

RESUMO

Fungal symbionts of terrestrial plants are among the most widespread and well-studied symbioses, relatively little is known about fungi that are associated with macroalgae. To fill the gap in marine fungal taxonomy, we combined simple culture methods with amplicon sequencing to characterize the fungal communities associated with three brown (Sargassum muticum, Pelvetia canaliculata, and Himanthalia elongata) and two red (Mastocarpus stellatus and Chondrus crispus) macroalgae from one intertidal zone. In addition to characterizing novel fungal diversity, we tested three hypotheses: fungal diversity and community composition vary (i) among species distributed at different tidal heights, (ii) among tissue types (apices, mid-thallus, and stipe), and (iii) among "isomorphic" C. crispus life cycle stages. Almost 70% of our reads were classified as Ascomycota, 29% as Basidiomycota, and 1% that could not be classified to a phylum. Thirty fungal isolates were obtained, 18 of which were also detected with amplicon sequencing. Fungal communities differed by host and tissue type. Interestingly, P. canaliculata, a fucoid at the extreme high intertidal, did not show differences in fungal diversity across the thallus. As found in filamentous algal endophytes, fungal diversity varied among the three life cycle stages in C. crispus. Female gametophytes were also compositionally more dispersed as compared to the fewer variable tetrasporophytes and male gametophytes. We demonstrate the utility of combining relatively simple cultivation and sequencing approaches to characterize and study macroalgal-fungal associations and highlight the need to understand the role of fungi in near-shore marine ecosystems.


Assuntos
Chondrus , Alga Marinha , Animais , Ecossistema , Endófitos , Estágios do Ciclo de Vida
11.
Carbohydr Polym ; 273: 118588, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560989

RESUMO

Ultrasound-assisted extraction was used to recover gelling biopolymers and antioxidant compounds from Chondrus crispus with improved biological potential. The optimal processing conditions were evaluated using a Box-Behnken design, and the impact on the biological and thermo-rheological properties of the carrageenan fraction and on the bioactive features of the soluble extracts were studied. The optimum extraction parameters were defined by extraction time of ~34.7 min; solid liquid ratio of ~2.1 g/100 g and ultrasound amplitude of ~79.0% with a maximum power of 1130 W. The dependent variables exhibited maximum carrageenan yields (44.3%) and viscoelastic modulus (925.9 Pa) with the lowest gelling temperatures (38.7 °C) as well as maximum content of the extract in protein (22.4 mg/g), gallic acid (13.4 mg/g) and Trolox equivalents antioxidant capacity (182.4 mg TEAC/g). Tested hybrid carrageenans exhibited promising biological activities (% of growth inhibition around 91% for four human cancer cellular lines: A549; A2780; HeLa 229; HT-29).


Assuntos
Antineoplásicos/farmacologia , Carragenina/farmacologia , Chondrus/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Carragenina/química , Carragenina/isolamento & purificação , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Módulo de Elasticidade , Humanos , Hidrogéis/química , Hidrogéis/isolamento & purificação , Hidrogéis/farmacologia , Ondas Ultrassônicas , Substâncias Viscoelásticas/química , Substâncias Viscoelásticas/isolamento & purificação , Substâncias Viscoelásticas/farmacologia
12.
Mar Drugs ; 19(8)2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34436292

RESUMO

Polyunsaturated fatty acids are well known for their protective properties in relation to different skin diseases. Although seaweeds possess a low lipid fraction, they could act as an alternative renewable source of polyunsaturated fatty acids whenever other valuable seaweed components are also valorized. In this study, a biorefinery process using Mastocarpus stellatus as a model seaweed was proposed. The process started with the supercritical carbon dioxide extraction of the lipid and phenolic fractions. The influence of pressure during extraction with pure supercritical CO2 was studied while operating at a selected temperature and solvent flow rate. Kinetic data obtained during the ethanol-modified supercritical CO2 extraction were fitted to the spline model. Sequential processing was proposed with (i) pure CO2 to obtain a product with 30% PUFA content and ω-3:ω-6 ratio 1:1, (ii) ethanol-modified CO2 to extract phenolics, and (iii) microwave-assisted subcritical water extraction operating under previously optimized conditions for the extraction of phenolics, carrageenan and protein fractions. The composition of the supercritical extracts showed potential for use in both dietary and topical applications in skin care products. The remaining solids are suitable for the extraction of other valuable fractions.


Assuntos
Chondrus , Ácidos Graxos/química , Fenóis/química , Organismos Aquáticos , Humanos , Extração Líquido-Líquido , Fitoterapia , Pressão , Solventes
13.
Bioorg Chem ; 116: 105302, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34464816

RESUMO

COX-2 selective drugs have been withdrawn from the market due to cardiovascular side effects, just a few years after their discovery. As a result, a new series of 1,5-diaryl pyrazole carboxamides 19-31 was synthesized as selective COX-2/sEH inhibitors with analgesic, anti-inflammatory, and lower cardiotoxic properties. The target compounds were synthesized and tested in vitro against COX-1, COX-2, and sEH enzymes. Compounds 20, 22 and 29 exhibited the most substantial COX-2 inhibitory activity (IC50 values: 0.82-1.12 µM) and had SIs of 13, 18, and 16, respectively, (c.f. celecoxib; SI = 8). Moreover, compounds 20, 22, and 29 were the most potent dual COX-2/sEH inhibitors, with IC50 values of 0.95, 0.80, and 0.85 nM against sEH, respectively, and were more potent than the standard AUDA (IC50 = 1.2 nM). Furthermore, in vivo studies revealed that these compounds were the most active as analgesic/anti-inflammatory derivatives with a good cardioprotective profile against cardiac biomarkers and inflammatory cytokines. Finally, the most active dual inhibitors were docked inside COX-2/sEH active sites to explain their binding modes.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Cardiotônicos/farmacologia , Inibidores Enzimáticos/farmacologia , Pirazóis/farmacologia , Ácido Acético , Analgésicos/efeitos adversos , Analgésicos/química , Animais , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/química , Comportamento Animal/efeitos dos fármacos , Cardiotônicos/efeitos adversos , Cardiotônicos/química , Chondrus , Ciclo-Oxigenase 2/metabolismo , Citocinas/antagonistas & inibidores , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/tratamento farmacológico , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/química , Epóxido Hidrolases/antagonistas & inibidores , Epóxido Hidrolases/metabolismo , Humanos , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirazóis/efeitos adversos , Pirazóis/química , Solubilidade , Relação Estrutura-Atividade
14.
Food Chem Toxicol ; 155: 112385, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34237393

RESUMO

Considering the importance of seaweeds for the development of sustainable and innovative food products, this study aimed to characterize the impact of hydrothermal processing on iodine, sodium, potassium, selenium, and arsenic concentrations of four seaweed species (S. latissima, L. digitata, U. pinnatifida, and C. crispus) and on the associated health risks-benefits for consumers. These elements revealed a common pattern for leachable fractions of iodine, total arsenic, and selenium: L. digitata ≥ S. latissima > C. crispus > U. pinnatifida after rehydration and boiling during different periods. The behavior for sodium was: S. latissima > L. digitata > C. crispus > U. pinnatifida, and for potassium: U. pinnatifida > L. digitata > S. latissima > C. crispus. Generally, the species that attained more significant losses were S. latissima and L. digitata. A health-relevant sodium/potassium ratio below 0.7 was found for all species except for U. pinnatifida. In some species, the risk-benefit analysis revealed that high iodine and arsenic levels might promote risks for consumption, even after 20 min boiling, but 5 g of processed U. pinnatifida could contribute to adequate iodine, sodium, potassium, and selenium intakes for all population groups. Standardized processing treatments of seaweeds can open new opportunities for the sector.


Assuntos
Arsênio/análise , Manipulação de Alimentos , Iodo/análise , Metais Leves/análise , Alga Marinha/química , Selênio/análise , Chondrus/química , Manipulação de Alimentos/métodos , Laminaria/química , Potássio/análise , Medição de Risco , Sódio/análise , Undaria/química , Água/análise
15.
J Phycol ; 57(5): 1590-1603, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34164823

RESUMO

Although variation among habitats in the ratio of gametophytes to sporophytes has been reported in various gigartinacean species, factors controlling the phase ratio remain poorly understood. Over 18 months, we examined the phase ratio of Chondrus ocellatus at three sites: a sheltered intertidal site, Hiruga A; an exposed intertidal site, Hiruga B; and a subtidal site, Shikimi. The mean proportion of gametophytes at Hiruga A (73.1%) was significantly higher than that at Shikimi (51.2%) and Hiruga B (44.7%). Due to a significantly higher water retention ability of the gametophytes, it was expected that the gametophytes would exhibit higher desiccation tolerance. After dehydration treatments, however, neither the photosynthetic rate of vegetative blades nor the survival rate of spores was significantly different between the phases. Measurements of blade strength indicated that the sporophytic blades were less stiff and more flexible, and a culture experiment revealed that the sporophytic germlings showed a significantly higher growth rate. Flexible blades and fast-growing germlings are considered advantageous for colonizing wave-swept intertidal habitats, so these properties may have caused the different fluctuation pattern of phase ratio among the sites. The present data demonstrate that biomechanical and physiological differences between the two phases of C. ocellatus make one phase advantageous in certain environmental conditions, and that these differences likely cause an unequal ratio of isomorphic phases.


Assuntos
Chondrus , Rodófitas , Células Germinativas Vegetais , Fotossíntese
16.
J Phycol ; 57(2): 645-654, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33314105

RESUMO

Foundation species provide physical structure that enhances the diversity and abundance of associated organisms. Canopy-forming seaweeds are known to act as foundation species on rocky shores by lowering temperature and desiccation stress. Direct solar radiation, including ultraviolet (UV) light, can also reduce photosynthetic rates in algae, cause oxidative stress and DNA damage. The reduction in UV exposure provided by an algal canopy could therefore be important for understory organisms, including the red alga Chondrus crispus on New England's (USA) rocky shores, and this relationship may be more important at higher tidal elevations with increased low-tide exposure time. In field experiments, we investigated the relationship between tidal elevation and an index of C. crispus UV exposure, the concentration of UV-absorbing pigments. Low on the shore, C. crispus grew without a canopy. Higher on the shore, in the mid-intertidal zone, C. crispus was found under the canopy-forming rockweed, Fucus distichus subsp. evanescens. At this elevation, C. crispus was shaded (>50%; >1 m above MLLW). We performed a canopy removal experiment that spanned the mid-zone where C. crispus and F. distichus subsp. evanescens co-occur and the low-zone (no canopy). Following canopy removal in the mid-zone, UV pigment concentrations increased with tidal elevation. After accounting for the effect of elevation, removal of the algal canopy resulted in UV-protective pigment concentrations 2-fold higher than in un-manipulated control plots. These results suggest that amelioration of solar UV exposure might be another mechanism by which canopy seaweeds, acting as foundation species, facilitate understory seaweeds on rocky shores.


Assuntos
Chondrus , Fucus , Alga Marinha , Ecossistema , Plantas
17.
J Biomed Mater Res A ; 109(7): 1136-1146, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32985066

RESUMO

Ability of high molecular weight (HMW) κ- and λ-carrageenans of the red marine algae Chondrus armatus and their low molecular weight degradation products (LMWDPs) (0.7-20 and 10-170 kDa respectively) to influence functional properties (motility and phagocytosis) of murine peritoneal macrophages was assessed in this study as an in vitro and a weeklong feeding experiment. We demonstrated that, with an exception of one, all carrageenan samples at 100 µg/ml increased cellular motility and dose-dependently decreased phagocytic activity; LMWDPs of λ-carrageenan suppressed motility and had no effect on phagocytosis. Oral administration of all the carrageenan samples at 100 µg/kg/day for 7 days to mice had no effect on their clinical appearance, body weight, weight of their liver, spleen or thymus or development of noticeable changes to their inner organs. All samples induced a shift of the cell composition of the peritoneal cavity towards macrophages. Consumption of LMWDPs of κ-carrageenan resulted in development of leukopenia, however, no changes to relative WBC count were introduced by either of the samples. All samples decreased murine peritoneal macrophages phagocytic activity, with λ-samples possessing higher efficacy than their κ-counterparts; all LMWDPs stimulated peritoneal macrophages motility, with κ-samples possessing higher efficacy than their λ-counterparts In conclusion, we have shown that κ- and λ-carrageenans of the C. armatus and their LMWDPs suppress phagocytotic activity of peritoneal macrophages under both in vitro and in vivo conditions. This allows them to be viewed as pharmacologically active substances andpropagates the need for their further investigation as such.


Assuntos
Carragenina/farmacologia , Chondrus/química , Fatores Imunológicos/farmacologia , Macrófagos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Animais , Carragenina/administração & dosagem , Carragenina/química , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/química , Macrófagos/imunologia , Camundongos
18.
J Sci Food Agric ; 101(4): 1507-1514, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32851673

RESUMO

BACKGROUND: Seaweeds have been eaten in the diets of coastal cultures for centuries; however, consumption of seaweeds has been limited in Western diets owing to undesirable sensory characteristics and lack of familiarity. Apart from healthful bioactive metabolites, seaweeds are good sources of fibre and minerals. They are nearly a complete protein and have a low fat content (mainly mono- or polyunsaturated). The objectives were (i) to investigate if the addition of brown seaweed, Ascophyllum nodosum, or red seaweed, Chondrus crispus, altered the chemical composition and sensory properties of whole-wheat bread; and (ii) to determine what percentage the addition of brown or red seaweed to whole-wheat bread is acceptable to consumers. The two seaweeds were incorporated into separate batches of whole-wheat bread by percentage weight flour at 0% (control), 2%, 4%, 6%, and 8%. RESULTS: The products containing the highest amounts of A. nodosum and C. crispus had the highest ash and total dietary fibre. A. nodosum and C. crispus breads were acceptable at 4% and 2% levels respectively. The attributes of no aftertaste, soft, and chewy drove consumer liking of the whole-wheat bread, whereas attributes dry, dense, strong aftertaste, and saltiness detracted from liking. CONCLUSION: This project's significance is to demonstrate the acceptability of seaweed in a Western population, which may lay the groundwork to encourage and promote the consumption of seaweed or to exemplify seaweed incorporation into foodstuffs. © 2020 Society of Chemical Industry.


Assuntos
Ascophyllum/química , Pão/análise , Chondrus/química , Aditivos Alimentares/química , Alga Marinha/química , Triticum/química , Ascophyllum/metabolismo , Chondrus/metabolismo , Comportamento do Consumidor , Farinha/análise , Aditivos Alimentares/metabolismo , Manipulação de Alimentos , Humanos , Alga Marinha/metabolismo , Paladar
19.
Environ Sci Pollut Res Int ; 27(36): 45737-45741, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32803579

RESUMO

Seaweeds are a basic food in the Asian diet. The search for functional and healthy foods has increased the seaweed consumption in Europe and the USA. Seaweeds are a source of essential elements such as iodine. However, high intake levels of iodine can cause damages to human health. Red seaweeds like dulse (Palmaria palmata) and Irish moss (Chondrus crispus) are common in shops and large stores. The iodine level in 30 samples of red seaweeds (dulse and Irish moss) has been determined by redox volumetry with sodium thiosulfate to determine the iodine content of both species and to assess the iodine dietary exposure from dulse and Irish moss consumption. Irish moss (3.86 ± 1.49 mg/kg dry weight) has the highest average iodine content. Four grams per day of dehydrated Irish moss seaweeds contributes greatly to the iodine recommended daily intake (DRI) for children (25.7%). The consumption of analyzed seaweeds (4 g/day) does not pose a health risk. However, the consumption of 286 g/day of Irish moss would lead to exceeding the UL for the adult population set at 1100 µg/day. It is necessary that the consumer respects the consumption guidelines of the seaweed packers.


Assuntos
Chondrus , Iodo , Alga Marinha , Adulto , Criança , Europa (Continente) , Humanos , Medição de Risco
20.
Regul Toxicol Pharmacol ; 117: 104762, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32805323

RESUMO

In the state of Mato Grosso do Sul, Brazil, Piper glabratum leaves are used as a popular medicine for pain and inflammation. We performed a phytochemical analysis and evaluated the effects of ethanolic extract (EEPG) obtained from leaves of P. glabratum on toxicity as well as the effects of application of the hexanic fraction (HXPG) and the hydroalcoholic fraction (HAPG) obtained from the EEPG on inflammatory parameters and pain in mice. Swiss mice were treated with EEPG (30-300 mg/kg body weight (b.w.)), HXPG (19.5 mg/kg b.w.) or HAPG (83.37 mg/kg b.w.) and then subjected to carrageenan-induced pleurisy and paw oedema tests, the spontaneous pain, and zymosan-induced intra-articular inflammation. Wistar rats were treated with EEPG to assess acute toxicity. Phytochemical analysis of the fractions demonstrated the presence of phytol and mixture of stigmasterol and ß-sitosterol in the fractions. In the acute toxicity test, LD50 above 2000 mg/kg b.w. was observed. The treatments reduced oedema, cold and mechanical hyperalgesia, leukocyte migration and protein exudation. The antihyperalgesic and anti-inflammatory properties of EEPG and fractions were demonstrated in the present study. These results from EEPG and HXPG may be related, at least in part, to modulation of the inflammatory mediators by phytol, stigmasterol and ß-sitosterol.


Assuntos
Analgésicos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Etanol/uso terapêutico , Piper , Extratos Vegetais/uso terapêutico , Folhas de Planta , Analgésicos/química , Analgésicos/isolamento & purificação , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Chondrus , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/tratamento farmacológico , Edema/patologia , Etanol/química , Feminino , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Hiperalgesia/patologia , Masculino , Camundongos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Wistar , Testes de Toxicidade Aguda/métodos
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