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1.
Int J Biol Macromol ; 258(Pt 2): 128859, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38134984

ABSTRACT

Microwave hydrothermal treatment was selected to extract valuable fractions with bioactive and gelling properties from Evernia prunastri lichen with potential for topical applications. The impact of the extraction processing conditions on the soluble extracts, mucilage fraction and residual solid phase was analyzed within a lichen global valorization approach. A particular stress was made on the thermo-rheological and structural characteristics of the extracted glucan and galactomannan polymers, the corresponding gelled matrices, and their cosmetic feasibility. Results revealed that the proposed microwave-assisted treatment showed a relevant influence on the phytochemical features of the aqueous soluble extracts, accounting the major protein content at 120 °C and the enhanced antioxidant and anti-tyrosinase properties at 140 °C. Extracts at 200 °C showed the highest anti-inflammatory (COX-1 and COX-2 inhibition) efficacies. The biopolymer analyses indicated that those recovered after lichen hydrothermal treatment at 160 °C featured a good extraction performance, the highest molecular weight, apparent viscosity, and antiproliferative potential. The thermo-rheological properties of the corresponding matrices formulated at 10 % and 60 or 80 °C exhibited the strongest and most thermo-reversible characteristics, as well as antifreezing feasibility. Another advantage of the selected fractions was the absence of skin irritation according to the in vitro skin irritation assay.


Subject(s)
Lichens , Parmeliaceae , Lichens/chemistry , Glucans , Polymers/chemistry , Gels
2.
Int J Biol Macromol ; 225: 952-963, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-36402385

ABSTRACT

Microwave-assisted hydrothermal processing was proposed to recover high valuable compounds with antioxidant and gelling features from Ulva spp. green seaweed. The influence of the extraction conditions on the solubles, ulvan fraction and residual solid phase was studied to achieve a global valorization of the seaweed. A particular emphasis was placed on the selective coagulation of ulvan stimulated by a bio-ionic liquid during the extraction process. The achieved outcomes indicated that the selected microwave treatment exhibited a notable impact on the phytochemical properties of the soluble extracts, with the highest values of sulfate and protein content at 160 °C, and the highest antioxidant features at 200 °C. The most prominent molecular weight distributions were also identified for systems hydrothermal treated at 160 °C. The ulvan analyses showed that those extracted after microwave treatment at 160 °C showed the highest yields, molecular weight and the strongest gel features from the rheological point of view. The presence of the chloride chlorine during the extraction process favored the ulvan performance and the enhancement of the corresponding viscoelastic properties.


Subject(s)
Ionic Liquids , Seaweed , Ulva , Ulva/chemistry , Antioxidants/chemistry , Microwaves , Polysaccharides/chemistry , Seaweed/chemistry , Chlorides
3.
Food Chem ; 383: 132450, 2022 Jul 30.
Article in English | MEDLINE | ID: mdl-35182861

ABSTRACT

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.


Subject(s)
Chondrus , Seaweed , Antioxidants/chemistry , Chondrus/chemistry , Desiccation , Freeze Drying , Seaweed/chemistry , Vegetables
4.
Int J Biol Macromol ; 203: 417-429, 2022 Apr 01.
Article in English | MEDLINE | ID: mdl-35077749

ABSTRACT

Tea industry generates many by-products which could be used to produce and incorporate bioactive tea extracts (TE) into nutraceuticals, cosmetics and/or clinical applications. However, sensibility to external factors is a major disadvantage hindering its utilization. This study deals with the implementation and characterization of suitable biopolymer delivery systems based on starch, carrageenan or alginate, as microencapsulation, to stabilize and protect TE through innovative thin-carbohydrate-coated formulations. TE were spray-dried and microencapsulated in recycled carrier materials (alginate, carrageenan or starch). Product yields varied from 55 to 58%. High microencapsulation and loading efficiencies were achieved (60-93% and 65-84%, respectively). Antioxidant capacity varied from 32 to 46 g Trolox/100 g extract, within different carrier-systems; which also showed promising rheological and UV-protective properties when transformed into gels. Total phenolic content, particle-size distribution, HPSEC-analysis, SEM-analysis and FTIR-analysis were also performed. In sum, this paper characterizes and discusses the high potential of these recycled carbohydrate-coated microparticles for future applications.


Subject(s)
Alginates , Starch , Carrageenan , Plant Extracts , Tea
5.
Bioresour Technol ; 342: 125882, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34560434

ABSTRACT

Microwave hydrothermal processing was employed to obtain valuable gelling or bioactive fractions from U. pinnatifida, assessing the processing conditions following a biorefinery concept. It was identified a relevant impact on the antioxidant properties, sulfate, protein and oligosaccharides content, with the highest values above 200 °C, although the maximum in fucose was obtained at 160 °C. The lowest temperature involved the highest minerals and sulfate content of the solid phases. Rheology indicated that hydrothermal treatment at 160 °C is adequate to extract alginates with structural and viscoelastic properties similar to those commercially available. The incorporation of the hydrothermal residual solids in the proposed alginate matrices favored the development of systems with potential non-food applications applications. Selected extracts, after an intensification stage using ultrasound, featured interesting biological activities for two human cancer cell lines (A2780; HeLa 229) with percentage of cellular inhibition > 83 and 57%, without positive effects on A549 and HCT-116.


Subject(s)
Ovarian Neoplasms , Undaria , Cell Line, Tumor , Female , Humans , Microwaves , Peptides
6.
Carbohydr Polym ; 273: 118588, 2021 Dec 01.
Article in English | MEDLINE | ID: mdl-34560989

ABSTRACT

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).


Subject(s)
Antineoplastic Agents/pharmacology , Carrageenan/pharmacology , Chondrus/chemistry , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Carrageenan/chemistry , Carrageenan/isolation & purification , Cell Line, Tumor , Drug Screening Assays, Antitumor , Elastic Modulus , Humans , Hydrogels/chemistry , Hydrogels/isolation & purification , Hydrogels/pharmacology , Ultrasonic Waves , Viscoelastic Substances/chemistry , Viscoelastic Substances/isolation & purification , Viscoelastic Substances/pharmacology
9.
Int J Biol Macromol ; 183: 1436-1449, 2021 Jul 31.
Article in English | MEDLINE | ID: mdl-34023369

ABSTRACT

Carrageenan was extracted from Mastocarpus stellatus using hot water extraction under atmospheric and pressurized conditions. The influence of heating temperature during a non-isothermal heating profile up to temperatures in the range 70-190 °C was studied to evaluate the extraction yields and properties of the carrageenan fraction. Under the selected conditions (130 °C), extracted carrageenan (CMs) was used for the green synthesis of gold nanoparticles (AuNPs). After the optimization of the reaction conditions, the synthesized gold nanoparticles (Au@CMs) were characterized by UV-Vis spectroscopy, Z potential measurements, electron microscopy, and X-ray diffraction analysis, which confirmed the formation of spherical, polycrystalline, and negatively charged nanoparticles with a mean diameter of 14.3 ± 2.1 nm. The study conducted by scanning transmission electron microscopy, energy dispersive X-ray analysis and mapping confirmed the presence of carrageenan stabilizing AuNPs. Finally, Fourier transformed infrared spectroscopy was performed to analyze the functional groups of CMs involved in the reduction and stabilization of AuNPs. The selective cytotoxicity and the antioxidant activity of the Au@CMs were evaluated in different cell lines and compared to the CMs. Au@CMs showed an improved antioxidant capacity in cells under oxidative stress and the induction of apoptosis in a monocytic cell line, while no antitumor effect was observed in a lung endothelial cell line.


Subject(s)
Carrageenan/chemistry , Gold/chemistry , Metal Nanoparticles/chemistry , Antioxidants/chemistry , Fourier Analysis , Microbial Sensitivity Tests , Plant Extracts/chemistry
10.
Rehabilitacion (Madr) ; 55(3): 171-174, 2021.
Article in Spanish | MEDLINE | ID: mdl-33810874

ABSTRACT

The Publisher regrets that this article is an accidental duplication of an article that has already been published in Rehabilitación (Madr), 55 (2021) 167-70, https://doi.org/10.1016/j.rh.2020.12.004. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal


Subject(s)
Physical and Rehabilitation Medicine , Telemedicine , Ambulatory Care Facilities , Consensus
12.
Curr Res Food Sci ; 2: 20-24, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32914107

ABSTRACT

This work deals with the study of tea stalks from pruning debris using environmental friendly extraction technology to offer new healthy properties. In the manufacturing tea industry, tea trees require to be pruned every year and most of their remains are discarded as a waste with no economic value. Microwave aqueous extraction and pressurized hot water extraction process (autohydrolysis) were used to recover bioactive compounds from the tea branches. Operating at a fixed solid: liquid ratio (1:15), the effect of the maximum heating temperatures from 140 to 220 °C was studied. Liquid extracts were analysed for total phenolic, oligosaccharides, protein, mineral and heavy metals content, as well as for antioxidant capacity. The antitumoral possibilities were also determined for selected samples. The obtained results indicated that both processes could be used as an alternative to recover bioactive compounds from tea wastes, although microwave-assisted extraction allowed saving time when compared with autohydrolysis processing. The temperature exhibited a relevant effect on the total phenolic content and antioxidant capacity, decreasing with the microwave treatment and increasing with the autohydrolysis temperature. The obtained extracts could be adequate for incorporation in food and non-food fields.

13.
Carbohydr Polym ; 248: 116830, 2020 Nov 15.
Article in English | MEDLINE | ID: mdl-32919545

ABSTRACT

This work deals with the use of microwave hydrodiffusion and gravity (MHG) for the recovery of hybrid carrageenans with specific mechanical features together with bioactive compounds. For this purpose, Mastocarpus stellatus red seaweed was used as raw material and the most adequate MHG processing conditions were studied. The physicochemical properties of the algae and the corresponding biopolymers, the fundamental characterisation of the bioactive compounds from the extracts (antioxidant capacity, sulfate content, protein content, among others) and the rheological features of the formulated gels were analysed. Results indicated that MHG is an adequate technique for obtaining functional extracts with potential applications in the food and non-food fields. Hybrid carrageenans with a wide range of viscoelastic features were recovered by MHG, saving time compared to conventional methods. The yields obtained for the recovered hybrid carrageenans and bioactive fractions were comparable to those obtained in red algae with conventional techniques.


Subject(s)
Carrageenan/chemistry , Gravitation , Microwaves , Rhodophyta/chemistry , Seaweed/chemistry , Algal Proteins/analysis , Antioxidants/isolation & purification , Antioxidants/metabolism , Biopolymers/chemistry , Biopolymers/isolation & purification , Carrageenan/isolation & purification , Food Technology/instrumentation , Food Technology/methods , Rheology , Spectroscopy, Fourier Transform Infrared , Sulfates/analysis
14.
Epidemiol Infect ; 147: e274, 2019 09 24.
Article in English | MEDLINE | ID: mdl-31547889

ABSTRACT

With the aim to elucidate gonococcal antimicrobial resistance (AMR)-risk factors, we undertook a retrospective analysis of the molecular epidemiology and AMR of 104 Neisseria gonorrhoeae isolates from clinical samples (urethra, rectum, pharynx and cervix) of 94 individuals attending a sexually transmitted infection clinic in Madrid (Spain) from July to October 2016, and explored potential links with socio-demographic, behavioural and clinical factors of patients. Antimicrobial susceptibility was determined by E-tests, and isolates were characterised by N. gonorrhoeae multi-antigen sequence typing. Penicillin resistance was recorded for 15.4% of isolates, and most were susceptible to tetracycline, cefixime and azithromycin; a high incidence of ciprofloxacin resistance (~40%) was found. Isolates were grouped into 51 different sequence types (STs) and 10 genogroups (G), with G2400, ST5441, ST2318, ST12547 and G2992 being the most prevalent. A significant association (P = 0.015) was evident between HIV-positive MSM individuals and having a ciprofloxacin-resistant strain. Likewise, a strong association (P = 0.047) was found between patient age of MSM and carriage of isolates expressing decreased susceptibility to azithromycin. A decrease in the incidence of AMR gonococcal strains and a change in the strain populations previously reported from other parts of Spain were observed. Of note, the prevalent multi-drug resistant genogroup G1407 was represented by only three strains in our study, while the pan-susceptible clones such as ST5441, and ST2318, associated with extragenital body sites were the most prevalent.


Subject(s)
Drug Resistance, Bacterial , Genotype , Gonorrhea/epidemiology , Gonorrhea/microbiology , Neisseria gonorrhoeae/classification , Neisseria gonorrhoeae/drug effects , Adolescent , Adult , Disk Diffusion Antimicrobial Tests , Female , Humans , Incidence , Male , Middle Aged , Molecular Epidemiology , Multilocus Sequence Typing , Neisseria gonorrhoeae/genetics , Neisseria gonorrhoeae/isolation & purification , Retrospective Studies , Risk Factors , Spain/epidemiology , Young Adult
15.
Int J Biol Macromol ; 124: 451-459, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30496857

ABSTRACT

Ultrasound assisted aqueous extraction of alginate from Sargassum muticum was proposed to minimize the use of chemicals, high temperatures and prolonged times, with comparable extraction yields to conventional acid/alkali procedures. The alginate, precipitated from the liquors obtained after ultrasound assisted extraction of fucoidan and phlorotannin fractions, and converted to alginic acid sodium salt by a green treatment was characterized by FTIR-ATR, 1H NMR, HPSEC, MALDI-TOF, rheology and citotoxitity. A clear influence of the sonication time was observed on the alginate molar mass, block structure, thermo-rheological and tumoral cell growth inhibition features. All tested hydrogels featured stable and thermo-reversible characteristics.


Subject(s)
Alginates/isolation & purification , Green Chemistry Technology , Hydrogels/pharmacology , Liquid-Liquid Extraction/methods , Sargassum/chemistry , Seaweed/chemistry , A549 Cells , Alginates/chemistry , Alginates/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , HCT116 Cells , Humans , Hydrogels/chemistry , Liquid-Liquid Extraction/instrumentation , Polysaccharides/chemistry , Polysaccharides/isolation & purification , Sonication/instrumentation , Sonication/methods , Tannins/chemistry , Tannins/isolation & purification
17.
Neurologia ; 32(8): 508-515, 2017 Oct.
Article in English, Spanish | MEDLINE | ID: mdl-27126568

ABSTRACT

INTRODUCTION: Informal caregivers of patients with Alzheimer's disease (AD) have a poor health-related quality of life (HRQOL). HRQOL is an increasingly common user-focused outcome measure. We have evaluated HRQOL longitudinally in caregivers of AD patients at baseline and at 12 months. METHODS: Ninety-seven patients diagnosed with AD according to the NINCDS-ADRDA (National Institute of Neurological and Communicative Disorders and Stroke, and Alzheimer's Disease and Related Disorders Association) and their 97 respective primary caregivers were included in the study. We analysed the following data at the baseline visit: sociodemographic data of both patients and carers, patients' clinical variables, and data related to the healthcare provided to patients by carers. HRQOL of caregivers was measured with the SF-36 questionnaire at baseline and 12 months later. RESULTS: At 12 months, primary caregivers scored lower in the 8 subscales of the SF-36 questionnaire; differences were statistically significant in all dimensions except for 'physical function' and 'social function'. Baseline scores in our sample were lower than those of the general population. 'Vitality' is the dimension that presented the lowest scores. CONCLUSION: HRQOL in caregivers of patients with Alzheimer's disease deteriorates over time and is poorer than that of the age- and sex-matched general population.


Subject(s)
Alzheimer Disease , Caregivers/psychology , Quality of Life , Aged , Alzheimer Disease/nursing , Female , Humans , Longitudinal Studies , Male , Middle Aged , Surveys and Questionnaires
18.
Int J Biol Macromol ; 86: 418-24, 2016 May.
Article in English | MEDLINE | ID: mdl-26827757

ABSTRACT

The sol-gel diagrams of kappa/iota-hybrid carrageenan (KI) extracted from Mastocarpus stellatus powders with two different average particle sizes of the seaweed powders (117.0 µm and 77.5 µm) prior to the biopolymer extraction, are reported for the first time, together with rheological properties of obtained KI gels. Extraction yields for KI isolated from algae and average molecular weight of KI, determined by gel permeation chromatography, decreased with increasing the particle size of the powder. Rheological results indicated that tested samples exhibited stable and weak gel properties, except those prepared at 1.5% KI in 1.0 mol/L NaCl where stronger gels were found. Aqueous KI extracts with larger molecular weight led to stronger gels and also formed gels at lower biopolymer concentration in NaCl above 0.15 mol/L. All gels reached stability after 20 min of maturation. The data sets showed a strong temperature dependency. Gel setting temperatures significantly depended on the KI and NaCl content, whereas gel melting temperatures (68.0 ± 0.7 °C) were independent of both salt concentrations.


Subject(s)
Carrageenan/chemistry , Rheology , Rhodophyta/chemistry , Carrageenan/isolation & purification , Gels , Industry
19.
Carbohydr Polym ; 136: 449-58, 2016 Jan 20.
Article in English | MEDLINE | ID: mdl-26572375

ABSTRACT

NaCl and KCl phase diagrams of two kappa/iota-hybrid carrageenans (KI) are established, and the rheological properties of obtained solutions and gels are reported. KI were extracted from Ahnfeltiopsis devoniensis and Chondrus crispus seaweeds and showed different chemical composition, 48 mol% of kappa carrageenan (K) and 52 mol% of iota carrageenan (I), and 78 mol% of K and 22 mol% of I, respectively. Phase diagrams are systematically compared those of blends of commercial K and I (K+I) showing equivalent chemical compositions. Results confirm that KI clearly differ from mixtures of K and I. K+I form gels at lower polysaccharide concentration and ionic strength, and exhibit gel separation from a liquid phase when large amount (>0.1 mol/L) of KCl is used. In contrast, no syneresis was found in KI gels formed under similar conditions. Both KI and K+I gels are strain hardening, and show a concentration scaling of the elasticity with exponents ranging from 1.1 to 3.2 depending on the type of salt and ionic strength. The strain at break of KI gels does not show salt specificity and is similar to the strain at break of K+I gels in KCl under similar salt and polysaccharide concentrations. K+I gels in NaCl are more fragile than in KCl, thus showing salt specificity.


Subject(s)
Carrageenan/chemistry , Chondrus/chemistry , Elasticity , Gels/chemistry , Phase Transition , Potassium/chemistry , Rheology , Sodium/chemistry
20.
Rehabilitación (Madr., Ed. impr.) ; 49(3): 156-161, jul.-sept. 2015. tab, ilus
Article in Spanish | IBECS | ID: ibc-136890

ABSTRACT

Introducción. El equinismo, que es la deformidad más frecuente en los pacientes con parálisis cerebral, aumenta la inestabilidad, dificulta la marcha y la adaptación a la silla de ruedas. La corrección del equinismo beneficia al niño deambulador, facilita la adecuada colocación del pie en el reposapiés de la silla de ruedas y la posibilidad de usar un calzado convencional en el niño que no tiene capacidad de marcha. El objetivo de este estudio es valorar si el uso nocturno de ortesis de tobillo-pie en ortoposición permite prevenir o diferir la aparición de equinismo y así evitar o retrasar la cirugía de alargamiento tendinoso. Material y método. Se ha realizado un estudio observacional descriptivo retrospectivo, revisando el historial clínico de pacientes diagnosticados de parálisis cerebral, tratados mediante ortesis de tobillo-pie nocturnas en la Unidad de Rehabilitación Infantil del Hospital Virgen Macarena. Resultados. De los 90 pacientes tratados con la ortesis de tobillo-pie nocturna, el 88,9% consiguió el rango de flexión dorsal necesario para la deambulación (≥ 10°) o la correcta adaptación a la silla de ruedas y al calzado (≥ 0°). Únicamente en 9 pacientes (10% de los casos) no se alcanzaron los objetivos pretendidos. Conclusión. El tratamiento preventivo con ortesis rígidas constituye una opción de primera línea en el tratamiento de la parálisis cerebral. El uso reglado y mantenido de las ortesis de tobillo-pie nocturnas puede retrasar la aparición del equinismo en la parálisis cerebral y permite diferir o evitar la cirugía con un beneficio funcional evidente (AU)


Introduction. Equinus, the most common deformity in patients with cerebral palsy, increases instability and impairs gait and adaptation to a wheelchair. Correction of equinus benefits walking children and aids proper placement of the foot on the footrest of a wheelchair. It also allows the possibility of using conventional footwear in children with no ability to walk. The aim of this study was to assess whether the use of an ankle-foot orthosis at night, keeping the foot in orthoposition, can prevent or delay the onset of equinus and thus prevent or delay tendon lengthening surgery. Material and methods. We performed a retrospective observational study based on a chart review of 90 patients diagnosed with cerebral palsy treated with a nocturnal ankle-foot orthosis in the Children's Rehabilitation Unit at Hospital Virgen Macarena in Spain. Results. Of the 90 patients treated with nocturnal ankle-foot orthosis, 88.9% achieved the dorsiflexion necessary for ambulation (≥ 10°) or adequate adaptation to a wheelchair and footwear (≥ 0°). Only 9 patients (10%) did not achieve the intended objectives with the use of the splint. Conclusion. Preventive treatment with a rigid ankle-foot orthosis is a widely accepted practice that constitutes a first-line option in the treatment of cerebral palsy. Systematic and persistent use of a nocturnal ankle-foot orthosis can delay the onset of equinus in cerebral palsy and can delay or avoid surgery, with a clear functional benefit (AU)


Subject(s)
Female , Humans , Male , Foot Orthoses/trends , Foot Orthoses , Equinus Deformity/prevention & control , Equinus Deformity/rehabilitation , Cerebral Palsy/complications , Cerebral Palsy/rehabilitation , Retrospective Studies , Somnambulism/complications , Somnambulism/rehabilitation , Equinus Deformity/physiopathology , Equinus Deformity/surgery , Equinus Deformity
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