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1.
Foods ; 12(7)2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37048293

RESUMO

Gelidium corneum (syn. sesquipedale) is an industrially and ecologically important species of red alga used for the production of high-quality agar. However, the species is also of growing interest for the production of other valuable compounds, such as mycosporine-like amino acids (MAAs), with potential cosmeceutical and biomedical applications. Novel methods using two pulsed power techniques, high-voltage electrical discharges (HVED) and pulsed electrical fields (PEF), were evaluated for efficacy of MAA extraction. Algal suspensions were prepared at two ratios (1:20 and 1:40 w:v). Four different extraction protocols were compared: (i) high-voltage electrical discharges, (ii) pulsed electric fields, (iii) maceration at room temperature, and (iv) maceration at 50 °C. The algae were treated in three states: freshly harvested, dried, and powdered. HVED and PEF treatments were effective when performed on fresh algae, and in particular the HVED treatment resulted in yields of MAAs twenty times higher than the control: 0.81 ± 0.05 mg/gDry Weight (DW) vs. 0.037 ± 0.002 mg/gDW. This effect was not observed to the same extent when the algae were dried or powdered, although HVED remained the most selective method overall.

2.
Mar Drugs ; 20(11)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36421995

RESUMO

Polybius henslowii, an abundant yet unexploited species of swimming crab, was investigated as a potential source of α-chitin and calcium lactate using deep eutectic solvents (DES) as extracting solvents. Choline chloride-malonic acid (CCMA) and choline chloride-lactic acid (CCLA) were used to obtain high purity α-chitin from ball-milled P. henslowii exoskeleton in 2 h at 120 °C, with yields of 12.05 ± 2.54% and 12.8 ± 1.54%, respectively. The physical and chemical characteristics of the obtained chitins were assessed using CHN elemental analysis, attenuated total reflectance-Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. Furthermore, the CCLA solvent was reusable three times with little effect on the extract purity, and calcium lactate was produced at the end of the recycling cycles. The ensuing calcium lactate was also characterized in terms of chemical and physical properties. The obtained chitin is a promising raw material for downstream processing and the double valorization pathway with the obtention of calcium salts may increase the viability of a DES-based approach for the processing of mineralized substrates.


Assuntos
Braquiúros , Quitina , Animais , Quitina/química , Solventes/química , Solventes Eutéticos Profundos , Colina/química
3.
Polymers (Basel) ; 14(7)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35406293

RESUMO

Nowadays, biopolymers are playing a fundamental role in our society because of the environmental issues and concerns associated with synthetic polymers. The aim of this Special Issue entitled 'Women in Polymer Science and Technology: Biopolymers' is highlighting the work designed and developed by women on biopolymer science and technology. In this context, this short review aims to provide an introduction to this Special Issue by highlighting some recent contributions of women around the world on the particular topic of biopolymer science and technology during the last 20 years. In the first place, it highlights a selection of important works performed on a number of well-studied natural polymers, namely, agar, chitin, chitosan, cellulose, and collagen. Secondly, it gives an insight into the discovery of new polysaccharides and enzymes that have a role in their synthesis and in their degradation. These contributions will be paving the way for the next generation of female and male scientists on this topic.

4.
Molecules ; 25(9)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32365755

RESUMO

With the increase in life expectancy, reducing the visible signs of skin aging has become a major issue. A reduction in collagen and hyaluronic acid synthesis by fibroblasts is a feature of skin aging. The green seaweed, Ulva intestinalis, is an abundant and rich source of nutrients, especially proteins and peptides. The aim of this study was to assess the potential cosmetic properties of a protein fraction from Ulva intestinalis (PROT-1) containing 51% of proteins and 22% of polysaccharides, and its enzymatic peptide hydrolysates on human dermal fibroblasts. PROT-1 was extracted using a patented acid- and solvent-free process (FR2998894 (B1)). The biochemical characterization and chromatographic analysis showed a main set of proteins (25 kDa). To demonstrate the anti-aging potential of PROT-1, fibroblast proliferation and collagen and hyaluronic acid production were assessed on fibroblast cell lines from donors aged 20 years (CCD-1059Sk) and 46 years (CCD-1090Sk). PROT-1 induced a significant increase in collagen and hyaluronic acid production per cell, and a reduction in cell proliferation without increasing cell mortality. These effects were reversed after protein hydrolysis of PROT-1, showing the central role of proteins in this promising anti-aging property.


Assuntos
Colágeno/biossíntese , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Ácido Hialurônico/biossíntese , Extratos Vegetais/farmacologia , Proteínas de Plantas/farmacologia , Pele/citologia , Ulva/química , Aminoácidos/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Humanos , Hidrólise , Peptídeos/química , Peptídeos/farmacologia , Extratos Vegetais/química , Proteínas de Plantas/química , Biossíntese de Proteínas/efeitos dos fármacos
5.
Mar Drugs ; 17(5)2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31091758

RESUMO

(1) Background: Brown and red algal sulfated polysaccharides have been widely described as anticoagulant agents. However, data on green algae, especially on the Ulva genus, are limited. This study aimed at isolating ulvan from the green macroalga Ulva rigida using an acid- and solvent-free procedure, and investigating the effect of sulfate content on the anticoagulant activity of this polysaccharide. (2) Methods: The obtained ulvan fraction was chemically sulfated, leading to a doubling of the polysaccharide sulfate content in a second ulvan fraction. The potential anticoagulant activity of both ulvan fractions was then assessed using different assays, targeting the intrinsic and/or common (activated partial thromboplastin time), extrinsic (prothrombin time), and common (thrombin time) pathways, and the specific antithrombin-dependent pathway (anti-Xa and anti-IIa), of the coagulation cascade. Furthermore, their anticoagulant properties were compared to those of commercial anticoagulants: heparin and Lovenox®. (3) Results: The anticoagulant activity of the chemically-sulfated ulvan fraction was stronger than that of Lovenox® against both the intrinsic and extrinsic coagulation pathways. (4) Conclusion: The chemically-sulfated ulvan fraction could be a very interesting alternative to heparins, with different targets and a high anticoagulant activity.


Assuntos
Anticoagulantes/farmacologia , Fibroblastos/efeitos dos fármacos , Ulva/química , Anticoagulantes/química , Anticoagulantes/isolamento & purificação , Testes de Coagulação Sanguínea , Enoxaparina/farmacologia , Heparina/farmacologia , Humanos , Plasma/efeitos dos fármacos
6.
Nat Prod Res ; 31(18): 2126-2136, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28147712

RESUMO

The aim of this study was to evaluate the potential anticoagulant activity of sulphated polysaccharide-containing extracts of six french edible marine macroalgae. Aqueous extracts of brown (Himanthalia elongata, Laminaria digitata, Ascophyllum nodosum, Fucus vesiculosus), green (Ulva lactuca) and red (Chondrus crispus) macroalgae were prepared and their biochemical properties were determined, including major biomolecules, sulphate and ash contents. The anticoagulant activity of each extract was investigated using different scales from the specific antithrombin-dependent pathway (anti-Xa and anti-IIa) to the intrinsic and/or common (Activated Partial Thromboplastin Time, APTT), extrinsic (Prothrombin Time, PT) or common (Thrombin Time, TT) anticoagulant pathways, and compared with those of commercial anticoagulants, heparin and Lovenox®. Laminaria digitata, Fucus vesiculosus and Chondrus crispus extracts showed a significant APTT anticoagulant capacity, only 5-fold lower than that of Lovenox®, which is a pure low molecular weight heparin used as an anticoagulant agent to prevent pulmonary embolism in patients undergoing surgery.


Assuntos
Anticoagulantes/farmacologia , Phaeophyceae/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Alga Marinha/química , Anticoagulantes/química , Coagulação Sanguínea/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Heparina/farmacologia , Humanos , Tempo de Tromboplastina Parcial
7.
Carbohydr Polym ; 157: 1306-1314, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-27987837

RESUMO

Ulvans from Ulva sp. were tested for their potential cosmetic properties on human dermal fibroblasts. The crude ulvans (ULVAN-01, 57kDa), extracted using a patented acid- and solvent-free process, were subjected to depolymerization using ion exchange resin to obtain a low molecular weight ulvan (ULVAN-DEP, 4kDa). The biochemical characterization and UHPLC-HRMS analyses of these extracted ulvans showed that they were of high purity and predominantly composed of a repeated ulvanobiouronic acid disaccharide. Fibroblast proliferation, as well as hyaluronan and collagen release were assessed, demonstrating that ULVAN-01 reduced fibroblast proliferation rate while ULVAN-DEP had no significant effect. Both ulvans were ineffective to induce collagen production but induced a significant increase in hyaluronan production, with a strong influence of the molecular weight. Thus, crude and depolymerized ulvans had different metabolic activities on dermal fibroblasts, which makes them promising to envisage further development in the skin care field.


Assuntos
Colágeno/metabolismo , Fibroblastos/efeitos dos fármacos , Ácido Hialurônico/metabolismo , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Ulva/química , Células Cultivadas , Humanos , Polissacarídeos/isolamento & purificação
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