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1.
Mar Drugs ; 21(2)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36827124

RESUMO

The development of greener processes for the sustainable utilization of raw materials is increasingly demanded for environmental and economic reasons. A rapid and chemical-free technique was proposed for the extraction of hybrid kappa/iota (6/4) carrageenan from Sarcopeltis (ex Gigartina) skottsbergii. After separation, carrageenans were analyzed by Fourier transform infrared attenuated total reflectance, high-performance size-exclusion chromatography, and rheology. Maximum carrageenan extraction yields up to 63-64% were obtained operating at 110 or at 160 °C, for 5-7 min considering the sum of the heating and cooling periods, but the extraction of the phenolic fraction was favored at 220 °C. The recovered carrageenan showed apparent viscous values around 103 mPa at the lowest tested shear rates (0.1 1/s) and could be suitable to formulate films. Furthermore, those carrageenans obtained under 140 °C showed gel characteristics without previous separation from the liquid extract, avoiding ethanolic precipitation and energy consumption. The antiradical properties correlated with the phenolic content in the liquid phase, but no influence of temperature on the reducing properties was observed. The microwave-assisted hydrothermal treatment could be an efficient tool without needing chemicals for the extraction of carrageenans, which showed adequate rheological properties for commercial uses.


Assuntos
Micro-Ondas , Rodófitas , Carragenina/química , Rodófitas/química , Temperatura , Reologia
2.
Mar Drugs ; 21(6)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37367644

RESUMO

One possible scheme of Rugulopteryx okamurae biomass valorization based on a green, rapid and efficient fractionation technique was proposed. Microwave-assisted pressurized hot water extraction was the technology selected as the initial stage for the solubilization of different seaweed components. Operation at 180 °C for 10 min with a 30 liquid-to-solid ratio solubilized more than 40% of the initial material. Both the alginate recovery yield (3.2%) and the phenolic content of the water-soluble extracts (2.3%) were slightly higher when distilled water was used as solvent. However, the carbohydrate content in the extract (60%) was similar for both solvents, but the sulfate content was higher for samples processed with salt water collected from the same coast as the seaweeds. The antiradical capacity of the extracts was related to the phenolic content in the extracts, but the cytotoxicity towards HeLa229 cancer cells was highest (EC50 = 48 µg/mL) for the extract obtained with distilled water at the lowest temperature evaluated. Operation time showed a relevant enhancement of the extraction performance and bioactive properties of the soluble extracts. The further fractionation and study of this extract would be recommended to extend its potential applications. However, due to the low extraction yield, emphasis was given to the solid residue, which showed a heating value in the range 16,102-18,413 kJ/kg and could be useful for the preparation of biomaterials according to its rheological properties.


Assuntos
Phaeophyceae , Extratos Vegetais , Extratos Vegetais/química , Micro-Ondas , Solventes/química , Água/química , Fenóis/química
3.
Mar Drugs ; 22(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38248641

RESUMO

The extract obtained by pressurized hot water extraction from Sargassum muticum, to recover the bioactive compound known as fucoidan, was fractionated using membranes of 100, 50, 30, 10, and 5 kDa, obtaining five retentates and the final permeate. These fractions were characterized for phloroglucinol content, protein content, sulfate content, and trolox equivalent antioxidant capacity (TEAC); apart from oligosaccharides, FTIR and molar mass distribution were also evaluated. Retentates of 100 and 50 kDa showed higher values for phloroglucinol, TEAC, and sulfate content. The rheology of the alginate fraction was also evaluated. Regarding the potential antitumoral activity, all fractions were assessed in MCF-7 cells using a metabolic activity assay based on the reduction of a tetrazolium compound, the most efficient being R100 and R50. Based on the results, these fractions were compared with commercial fucoidans at the same concentrations, and similar results were found. In addition, synergistic cytotoxic effects using two drugs commonly used in breast cancer, cis-Platinum (cis-Pt) and 5-fluorouracil (5-FU), were tested in combination with R100 and R50. Promising results were obtained when the retentate and the drugs were mixed, showing an improvement in the cytotoxicity induced by the chemotherapy.


Assuntos
Sargassum , Peso Molecular , Polissacarídeos/farmacologia , Antioxidantes/farmacologia , Fluoruracila , Floroglucinol , Sulfatos
4.
Mar Drugs ; 21(12)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38132939

RESUMO

This work deals with the formulation of natural cosmetics enriched with antioxidant fractions from the ultrasound treatment (US) of the brown seaweed Saccharina latissima. The challenge was the development of a cosmetic matrix without jeopardizing the thermorheological features of the creams, adding microparticles containing the antioxidant fractions using two different carriers, mannitol and alginate. The fundamental chemical characteristics of seaweed and the extracts obtained via sonication, as well as the antioxidant properties of the latter, were analyzed. The highest TEAC (Trolox equivalent antioxidant capacity) value was identified for the extracts subjected to the longest processing time using ultrasound-assisted extraction (240 min). A similar yield of microparticle formulation (around 60%) and load capacity (about 85%) were identified with mannitol and alginate as carriers. Color testing of the creams exhibited small total color differences. The rheological results indicated that the testing temperature, from 5 to 45 °C, notably influenced the apparent viscosity of the matrices. All creams were adequately fitted with the two parameters of the Ostwald-de Waele model, with the flow consistency index following an Arrhenius dependency with the testing temperature. Neither hysteresis nor water syneresis was observed in the proposed cosmetics during 6 months of cold storage at 4-6 °C.


Assuntos
Cosméticos , Alga Marinha , Antioxidantes/farmacologia , Alga Marinha/química , Alginatos , Verduras , Manitol
5.
Mar Drugs ; 21(2)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36827156

RESUMO

The composition of seaweeds is complex, with vitamins, phenolic compounds, minerals, and polysaccharides being some of the factions comprising their structure. The main polysaccharide in brown seaweeds is fucoidan, and several biological activities have been associated with its structure. Chitosan is another marine biopolymer that is very popular in the biomedical field, owing to its suitable features for formulating drug delivery systems and, particularly, particulate systems. In this work, the ability of fucoidan to produce nanoparticles was evaluated, testing different amounts of a polymer and using chitosan as a counterion. Nanoparticles of 200-300 nm were obtained when fucoidan prevailed in the formulation, which also resulted in negatively charged nanoparticles. Adjusting the pH of the reaction media to 4 did not affect the physicochemical characteristics of the nanoparticles. The IC50 of fucoidan was determined, in both HCT-116 and A549 cells, to be around 160 µg/mL, whereas it raised to 675-100 µg/mL when nanoparticles (fucoidan/chitosan = 2/1, w/w) were tested. These marine materials (fucoidan and chitosan) provided features suitable to formulate polymeric nanoparticles to use in biomedical applications.


Assuntos
Quitosana , Fucus , Nanopartículas , Alga Marinha , Sulfatos , Fucus/química , Quitosana/química , Polissacarídeos/química , Nanopartículas/química
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.
Int J Mol Sci ; 23(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36430716

RESUMO

Osteoarthritis, one of the most common joint degenerative pathologies, still has no cure, and current treatments, such as nonsteroidal anti-inflammatory drugs, can cause serious adverse effects when taken for a long time. Brown seaweed crude fucoidans are used for the clinical treatment of several pathologies. In this study, the therapeutical potential of these biocompounds was analyzed in primary chondrocytes and the 260TT human chondrocyte cell line. Crude fucoidan from Undaria pinnatifida (Up) and Sargassum muticum (Sm) was obtained by different extraction techniques (microwave-assisted extraction, pressurized hot-water extraction, ultrasound-assisted extraction) and chemically and structurally characterized by Fourier transform infrared spectroscopy, high-performance size-exclusion chromatography, proton nuclear magnetic resonance, and scanning electron microscopy. Once cell viability was confirmed in chondrocytes treated with crude fucoidans, we evaluated their anti-inflammatory effects, observing a significant reduction in IL-6 production stimulated by IL-1ß. Findings were confirmed by analysis of IL-6 and IL-8 gene expression, although only fucoidans from Up achieved a statistically significant reduction. Besides this, the antioxidant capacity of crude fucoidans was observed through the upregulation of Nrf-2 levels and the expression of its transcriptional target genes HO-1 and SOD-2, with compounds from Up again showing a more consistent effect. However, no evidence was found that crude fucoidans modulate senescence, as they failed to reduced ß-galactosidase activity, cell proliferation, or IL-6 production in chondrocytes stimulated with etoposide. Thus, the findings of this research seem to indicate that the tested crude fucoidans are capable of partially alleviating OA-associated inflammation and oxidative stress, but fail to attenuate chondrocyte senescence.


Assuntos
Osteoartrite , Undaria , Humanos , Interleucina-6 , Polissacarídeos/farmacologia , Polissacarídeos/química , Osteoartrite/tratamento farmacológico , Osteoartrite/patologia , Anti-Inflamatórios
8.
Mar Drugs ; 19(5)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069393

RESUMO

Ultrasound-assisted water extraction was optimized to recover gelling biopolymers and antioxidant compounds from Mastocarpus stellatus. A set of experiments following a Box-Behnken design was proposed to study the influence of extraction time, solid liquid ratio, and ultrasound amplitude on the yield, sulfate content, and thermo-rheological properties (viscoelasticity and gelling temperature) of the carrageenan fraction, as well as the composition (protein and phenolic content) and antiradical capacity of the soluble extracts. Operating at 80 °C and 80 kHz, the models predicted a compromise optimum extraction conditions at ~35 min, solid liquid ratio of ~2 g/100 g, and ultrasound amplitude of ~79%. Under these conditions, 40.3% carrageenan yield was attained and this product presented 46% sulfate and good mechanical properties, a viscoelastic modulus of 741.4 Pa, with the lowest gelling temperatures of 39.4 °C. The carrageenans also exhibited promising antiproliferative properties on selected human cancer cellular lines, A-549, A-2780, HeLa 229, and HT-29 with EC50 under 51.9 µg/mL. The dried soluble extract contained 20.4 mg protein/g, 11.3 mg gallic acid eq/g, and the antiradical potency was equivalent to 59 mg Trolox/g.


Assuntos
Carragenina/isolamento & purificação , Carragenina/farmacologia , Proliferação de Células/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Rodófitas/química , Antioxidantes/química , Carragenina/análise , Carragenina/química , Linhagem Celular Tumoral , Géis , Humanos , Fenômenos Mecânicos , Fenóis/química , Extratos Vegetais/análise , Extratos Vegetais/química , Reologia , Sulfatos/análise , Temperatura , Ondas Ultrassônicas , Viscosidade , Água/química
9.
Mar Drugs ; 19(8)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34436276

RESUMO

Carrageenan and carrageenan oligosaccharides are red seaweed sulfated carbohydrates with well-known antiviral properties, mainly through the blocking of the viral attachment stage. They also exhibit other interesting biological properties and can be used to prepare different drug delivery systems for controlled administration. The most active forms are λ-, ι-, and κ-carrageenans, the degree and sulfation position being determined in their properties. They can be obtained from sustainable worldwide available resources and the influence of manufacturing on composition, structure, and antiviral properties should be considered. This review presents a survey of the antiviral properties of carrageenan in relation to the processing conditions, particularly those assisted by intensification technologies during the extraction stage, and discusses the possibility of further chemical modifications.


Assuntos
Antivirais/química , Carragenina/química , Alga Marinha , Antivirais/farmacologia , Organismos Aquáticos , Carragenina/farmacologia , Humanos , Fitoterapia
10.
Molecules ; 26(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34443312

RESUMO

Subcritical water extraction of Himanthalia elongata and the subsequent acetone fractionation to precipitate crude fucoidans generated a liquid phase which was used to recover alginates with a wide range of viscoelastic features and other soluble extracts with potential biological activities. The precipitated alginate was converted to sodium alginate using an environmentally friendly treatment before being characterized by Fourier transform infrared attenuated total reflectance, nuclear magnetic resonance, high performance size exclusion chromatography and rheological measurements. The cell viability of three human cell lines (A549, HCT-116, T98G) in the presence of the extracts obtained before and after acetone fractionation was assessed. Fractionation with different acetone volumes showed a slight effect in the behavior of the different tested cell lines. Results also indicated a notable effect of the processing conditions on the block structure and molar mass of the extracted biopolymer, with the subsequent impact on the rheological properties of the corresponding gelled matrices.


Assuntos
Alginatos/isolamento & purificação , Phaeophyceae/química , Água/química , Alginatos/química , Alginatos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Conformação Molecular , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
11.
Molecules ; 26(14)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34299659

RESUMO

The integral valorization of artichoke bracts generated during industrial canning of artichoke was assessed. The extraction of bioactive compounds was addressed with pressurized hot water under subcritical conditions. The performance of this stage on the extraction of phenolics with antioxidant properties and the saccharidic fraction using conventional and microwave heating was compared. The microwave assisted process was more efficient than the conventional one regarding extraction yields of total solubles, and glucose and fructose oligomers and phenolics, because lower operational temperatures and shorter times were needed. Degradation of fructose oligomers was observed at temperatures higher than 160 °C, whereas the maximal phenolic content occurred at 220 °C. Both the extracts and the residual solids, obtained at conditions leading to maximum phenolics yields, were evaluated for the production of starch-based hydrogels, supplemented with Paulownia leaves' aqueous extracts.


Assuntos
Cynara scolymus/química , Química Verde , Temperatura Alta , Hidrogéis , Lamiales/química , Extratos Vegetais/química , Hidrogéis/síntese química , Hidrogéis/química
12.
Molecules ; 26(21)2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34770811

RESUMO

Aristotelia chilensis is a plant rich in phenolics and other bioactive compounds. Their leaves are discarded as waste in the maqui berry industry. A new application of these wastes is intended by the recovery of bioactive compounds using pressurized hot water extraction with conventional or microwave heating. Both technologies have been selected for their green character regarding the type of solvent and the high efficiency in shorter operation times. Extractions were performed in the temperature range 140-200 °C with a solid/liquid ratio of 1:15 (w:w). The extracts' total phenolic content, antioxidant capacity, and saccharides content obtained with both heating methods were measured. Additionally, the thermo-rheological properties of the gelling matrix enriched with these extracts were analyzed. Optimum conditions for lyophilized extracts were found with conventional heating, at 140 °C and 20 min extraction; 250.0 mg GAE/g dry extract and 1321.5 mg Trolox/g dry extract. Close to optimum performance was achieved with microwave heating in a fraction of the time (5 min) at 160 °C (extraction), yielding extracts with 231.9 mg GAE/g dry extract of total phenolics and antiradical capacity equivalent to 1176.3 mg Trolox/g dry extract. Slightly higher antioxidant values were identified for spray-dried extracts (between 5% for phenolic content and 2.5% for antioxidant capacity). The extracts obtained with both heating methods at 200 °C contained more than 20% oligosaccharides, primarily glucose. All the formulated gelling matrices enriched with the obtained extracts displayed intermediate gel strength properties. The tested technologies efficiently recovered highly active antioxidant extracts, rich in polyphenolics, and valuable for formulating gelling matrices with potential applicability in foods and other products.


Assuntos
Elaeocarpaceae/química , Glucose/isolamento & purificação , Hidrogéis/química , Oligossacarídeos/isolamento & purificação , Glucose/química , Oligossacarídeos/química , Pressão , Temperatura , Água/química
13.
Mar Drugs ; 18(7)2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32605020

RESUMO

A green extraction process using only water was proposed for the simultaneous extraction of alginate and bioactive compounds from Laminaria ochroleuca. Operation was carried out during non-isothermal heating up to maximal temperatures over the range of 70 °C to 100 °C. Once separated, the alginate and the crude extract were characterised and the biological activities and cytotoxicity of the extracts was studied, the latter in intestinal epithelial cells. Those alginates obtained at 90 °C exhibited the highest extraction yields and viscoelastic features of the corresponding hydrogels. The obtained results show that the extracts obtained by non-isothermal extraction were suitable to formulate nanoparticles, which showed the smallest size (≈ 250-350 nm) when the higher content of fucoidan extract was present. Given the evidenced properties, the extracts may find an application in the formulation of nanoparticulate carriers for drug delivery.


Assuntos
Misturas Complexas/química , Química Verde/métodos , Laminaria/química , Nanopartículas/química , Polímeros/química , Alginatos/química , Alginatos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Sobrevivência Celular , Células HCT116 , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Mar Drugs ; 17(6)2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31142051

RESUMO

The hydrocolloids carrageenan and agar are the major fraction industrially extracted and commercialized from red seaweeds. However, this type of macroalgae also contains a variety of components with nutritional, functional and biological properties. In the context of sustainability and bioeconomy, where the integral utilization of the natural resources is incentivized, the sequential separation and valorization of seaweed components with biological properties of interest for food, nutraceuticals, cosmeceuticals and pharmaceuticals is proposed. In this work, a review of the available conventional and alternative greener and efficient extraction for obtaining red seaweed bioactives is presented. The potential of emerging technologies for the production of valuable oligomers from carrageenan and agar is also commented, and finally, the sequential extraction of the constituent fractions is discussed.


Assuntos
Compostos Fitoquímicos/isolamento & purificação , Rodófitas/química , Ágar/isolamento & purificação , Carragenina/isolamento & purificação , Indústria Farmacêutica , Indústria Alimentícia , Química Verde
15.
Molecules ; 25(1)2019 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-31881788

RESUMO

Microwave hydrodiffusion and gravity (MHG) and ethanolic solid-liquid extraction were compared using selected plant sources. Their bioactive profile, color features, and proximate chemical characterization were determined. MHG extracts, commercial antioxidants, and three distinct types of thermal spring water were used in a sunscreen cream formulation. Their bioactive capacity, chemical and rheological properties were evaluated. MHG Cytisus scoparius flower extract provided the highest bioactive properties. Pleurotus ostreatus MHG liquor exhibited the highest total solid extraction yield. The Brassica rapa MHG sample stood out for its total protein content and its monosaccharide and oligosaccharide concentration. Quercus robur acorns divided into quarters supplied MHG extract with the lowest energy requirements, highest DPPH inhibition percentage, total lipid content and the highest enzyme inhibition. The chemical and bioactive capacities stability of the sunscreen creams elaborated with the selected MHG extracts and the thermal spring waters showed a similar behavior than the samples containing commercial antioxidants.


Assuntos
Cosméticos/química , Gravitação , Micro-Ondas , Plantas/química , Antioxidantes/farmacologia , Carotenoides/análise , Cor , Difusão , Lipídeos/análise , Fenóis/análise , Proteínas/análise , Protetores Solares/farmacologia , Temperatura , Fatores de Tempo , Viscosidade
16.
Arch Orthop Trauma Surg ; 139(5): 669-674, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30560289

RESUMO

AIM: To evaluate the influence of the specific procedure performed and other variables on the intensity of acute postoperative pain following outpatient shoulder arthroscopy. METHODS: One hundred patients undergoing outpatient shoulder arthroscopy under single-shot interscalene block plus general anaesthesia were prospectively studied. Acetaminophen with ibuprofen was prescribed for postoperative pain control and tramadol HCl as rescue medication. Patients scored pain intensity at 2, 6, and 24 h postoperatively. The influence of the surgical procedure, age, gender, surgery duration, and irrigation volume used on the intensity of postoperative pain was studied. RESULTS: Five patients were excluded due to ineffective block or protocol deviation. Among the 95 remaining patients, 51 underwent rotator cuff tear repair, 25 shoulder stabilisation, and 19 subacromial decompression. While there were no differences at 2 and 6 h after surgery, pain intensity was significantly higher among those undergoing rotator cuff tear repair (5.2, 1-10) at 24 h compared to stabilisation (4.1, 1-8) or subacromial decompression (5, 1-8) (p < 0.0001). No association was found between pain intensity and other variables. CONCLUSION: A higher degree of acute postoperative pain should be expected in patients undergoing arthroscopic rotator cuff tear repair compared to other arthroscopic shoulder procedures, and additional pain treatment is recommended.


Assuntos
Artroscopia/efeitos adversos , Dor Pós-Operatória/etiologia , Lesões do Manguito Rotador/cirurgia , Manguito Rotador/cirurgia , Dor de Ombro/etiologia , Adulto , Idoso , Procedimentos Cirúrgicos Ambulatórios , Anestesia Geral , Artroscopia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Bloqueio Nervoso/métodos , Manejo da Dor , Medição da Dor , Dor Pós-Operatória/tratamento farmacológico , Estudos Prospectivos , Lesões do Manguito Rotador/complicações , Dor de Ombro/tratamento farmacológico
17.
Appl Environ Microbiol ; 82(15): 4652-62, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27235437

RESUMO

UNLABELLED: Phosphorus (P) plays a fundamental role in the physiology and biochemistry of all living things. Recent evidence indicates that organisms in the oceans can break down and use P forms in different oxidation states (e.g., +5, +3, +1, and -3); however, information is lacking for organisms from soil and sediment. The Cuatro Ciénegas Basin (CCB), Mexico, is an oligotrophic ecosystem with acute P limitation, providing a great opportunity to assess the various strategies that bacteria from soil and sediment use to obtain P. We measured the activities in sediment and soil of different exoenzymes involved in P recycling and evaluated 1,163 bacterial isolates (mainly Bacillus spp.) for their ability to use six different P substrates. DNA turned out to be a preferred substrate, comparable to a more bioavailable P source, potassium phosphate. Phosphodiesterase activity, required for DNA degradation, was observed consistently in the sampled-soil and sediment communities. A capability to use phosphite (PO3 (3-)) and calcium phosphate was observed mainly in sediment isolates. Phosphonates were used at a lower frequency by both soil and sediment isolates, and phosphonatase activity was detected only in soil communities. Our results revealed that soil and sediment bacteria are able to break down and use P forms in different oxidation states and contribute to ecosystem P cycling. Different strategies for P utilization were distributed between and within the different taxonomic lineages analyzed, suggesting a dynamic movement of P utilization traits among bacteria in microbial communities. IMPORTANCE: Phosphorus (P) is an essential element for life found in molecules, such as DNA, cell walls, and in molecules for energy transfer, such as ATP. The Valley of Cuatro Ciénegas, Coahuila (Mexico), is a unique desert characterized by an extreme limitation of P and a great diversity of microbial life. How do bacteria in this valley manage to obtain P? We measured the availability of P and the enzymatic activity associated with P release in soil and sediment. Our results revealed that soil and sediment bacteria can break down and use P forms in different oxidation states and contribute to ecosystem P cycling. Even genetically related bacterial isolates exhibited different preferences for molecules, such as DNA, calcium phosphate, phosphite, and phosphonates, as substrates to obtain P, evidencing a distribution of roles for P utilization and suggesting a dynamic movement of P utilization traits among bacteria in microbial communities.


Assuntos
Bactérias/metabolismo , Sedimentos Geológicos/análise , Fósforo/metabolismo , Solo/química , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Biodiversidade , Ecossistema , Sedimentos Geológicos/microbiologia , Fósforo/análise , Filogenia , Microbiologia do Solo
18.
Int J Biol Macromol ; 266(Pt 2): 131456, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38588844

RESUMO

The red macroalga Sarcopeltis skottsbergii was subjected to hydrothermal processing to maximize the solubilization and recovery of carrageenan. Once isolated by ethanol precipitation, the carrageenan was further chemically (oligosaccharides composition), and structurally (TGA/DTG, DSC, HPSEC, FTIR-ATR, 1H NMR, SEM, etc.) characterized, as well as employed as source for the synthesis of hydrogels. The rheological properties of the carrageenan showed promising results as biopolymer for food applications due to the high molecular weight (500 kDa) presenting higher cell viability than 70 %. The evaluation of immune activation using ELISA test reflected a lower inflammatory response for concentrations of 0.025 % of carrageenan. Conversely, the cell viability of the synthesized hydrogels did not surpass 50 %. This work represents a considerable step forward to obtain a biopolymer from natural sources and a thorough study of their chemical, structural and biological properties.


Assuntos
Carragenina , Hidrogéis , Rodófitas , Engenharia Tecidual , Carragenina/química , Engenharia Tecidual/métodos , Hidrogéis/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Reologia , Humanos , Materiais Biocompatíveis/química , Peso Molecular
19.
Foods ; 12(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37174397

RESUMO

Several bioactive compounds that hold a potential interest in the food industry as phenolic compounds, polysaccharides, proteins and vitamins, among others, are present in seaweeds. Green extraction technologies are the preferred way to obtain these compounds. Pressurized hot water extraction, from 160 to 220 °C, was tested to achieve high yields of these components from the edible brown seaweed, Undaria pinnatifida. The maximum fucoidan content was recovered at 160 °C, while the phloroglucinol content and antioxidant activity were maximum at 220 °C. The possibility of encapsulating these bioactive fractions using mannitol was assessed. The highest production yield of the polymeric particles was found using the 220 °C fraction (close to 75%). In order to formulate microparticles with bioactive potential, several ratios of liquid phases were assessed, 3:1, 1:1 and 1:3 (w:w), using the liquid fractions obtained at 160 °C and 220 °C. The yield production was always above 67%, being in the 1:3 ratio (160 °C:220 °C) and close to 75%. The rheological results indicated that the presence of microparticles enhanced the apparent viscosity of the aqueous dispersions with non-Newtonian profiles, achieving the highest viscosity for those formulated with microparticles from 160 °C:200 °C (3:1).

20.
Foods ; 12(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37893773

RESUMO

The formulation of polymeric microparticles to encapsulate bioactive compounds from two hop varieties (Nugget and Perle) using sequential green extraction processes was performed. The technologies used were ultrasound-assisted extraction (UAE) and pressurized hot water (PHW) extraction. Liquid phases were analyzed for total phenolic content (~2%), antioxidant activity (IC50, DPPH: 3.68 (Nugget); 4.46 (Perle) g/L, TEAC (~4-5%), FRAP (~2-3%), and reducing power (~4%)), protein content (~1%), oligosaccharide content (~45%), and for structural features. The fractions obtained from UAE were selected to continue with the drying process, achieving the maximum yield at 120 °C (Perle) and 130 °C (Nugget) (~77%). Based on these results, the formulation of polymeric microparticles using mannitol as the carrier was performed with these fractions. The production yield (~65%), particle size distribution (Perle: 250-750 µm and Nugget: ~100 µm), and rheological features (30-70 mPa s at 0.1 s-1) were the parameters evaluated. The UAE extracts from hop samples processed using a sustainable aqueous treatment allowed the formulation of microparticles with a suitable yield, and morphological and viscosity properties adequate for potential food and non-food applications.

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