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1.
Environ Sci Technol ; 56(6): 3452-3461, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35245029

RESUMEN

Microbial reduction of inorganic divalent mercury (Hg2+) and methylmercury (MeHg) demethylation is performed by the mer operon, specifically by merA and merB genes, respectively, but little is known about the mercury tolerance capacity of marine microorganisms and its prevalence in the ocean. Here, combining culture-dependent analyses with metagenomic and metatranscriptomic data, we show that marine bacteria that encode mer genes are widespread and active in the global ocean. We explored the distribution of these genes in 290 marine heterotrophic bacteria (Alteromonas and Marinobacter spp.) isolated from different oceanographic regions and depths, and assessed their tolerance to diverse concentrations of Hg2+ and MeHg. In particular, the Alteromonas sp. ISS312 strain presented the highest tolerance capacity and a degradation efficiency for MeHg of 98.2% in 24 h. Fragment recruitment analyses of Alteromonas sp. genomes (ISS312 strain and its associated reconstructed metagenome assembled genome MAG-0289) against microbial bathypelagic metagenomes confirm their prevalence in the deep ocean. Moreover, we retrieved 54 merA and 6 merB genes variants related to the Alteromonas sp. ISS312 strain from global metagenomes and metatranscriptomes from Tara Oceans. Our findings highlight the biological reductive MeHg degradation as a relevant pathway of the ocean Hg biogeochemical cycle.


Asunto(s)
Mercurio , Compuestos de Metilmercurio , Bacterias/genética , Bacterias/metabolismo , Mercurio/metabolismo , Compuestos de Metilmercurio/metabolismo , Océanos y Mares , Prevalencia
2.
Molecules ; 26(2)2021 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-33435343

RESUMEN

Water-in-oil-in-water (W1/O/W2) emulsions are emulsion-based systems where the dispersed phase is an emulsion itself, offering great potential for the encapsulation of hydrophilic bioactive compounds. However, their formation and stabilization is still a challenge mainly due to water migration, which could be reduced by lipid phase gelation. This study aimed to assess the impact of lipid phase state being liquid or gelled using glyceryl stearate (GS) at 1% (w/w) as well as the hydrophilic emulsifier (T80: Tween 80 or lecithin) and the oil type (MCT:medium chain triglyceride or corn oil (CO) as long chain triglyceride) on the formation and stabilization of chlorophyllin W1/O/W2 emulsions. Their colloidal stability against temperature and light exposure conditions was evaluated. Gelling both lipid phases (MCT and CO) rendered smaller W1 droplets during the first emulsification step, followed by formation of W1/O/W2 emulsions with smaller W1/O droplet size and more stable against clarification. The stability of W1/O/W2 emulsions was sensitive to a temperature increase, which might be related to the lower gelling degree of the lipid phase at higher temperatures. This study provides valuable insight for the formation and stabilization of W1/O/W2 emulsions with gelled lipid phases as delivery systems of hydrophilic bioactive compounds under common food storage conditions.


Asunto(s)
Emulsionantes/química , Lípidos/química , Aceite de Maíz/química , Emulsiones , Geles/química , Interacciones Hidrofóbicas e Hidrofílicas , Tamaño de la Partícula , Polisorbatos/química , Agua/química
3.
Biomacromolecules ; 16(9): 2895-903, 2015 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-26313761

RESUMEN

The aim of this work was to study the influence of biopolymer (alginate, ALG; chitosan, CHI) charge on the formation of multilayer nanofilms by the layer-by-layer (LbL) technique. The electrical charge of ALG and CHI (high, medium, or low) was modulated by adjusting the pH of biopolymer solutions. The amount of biopolymer deposited in multilayers depended on the charge of ALG and CHI solutions. The lower the charge the higher the deposition rate due to the higher number of biopolymer molecules needed to neutralize the previous layer. Medium and low charge biopolymers led to a drastic change in the wettability of multilayers, with ALG layers being strongly hydrophilic and CHI layers strongly hydrophobic. The surface ζ-potential alternatively changed from negative to positive using ALG or CHI. This effect was more pronounced using highly charged biopolymers. Results obtained in this study evidenced that the multilayers properties can be tuned by controlling the biopolymer electrical charge.


Asunto(s)
Alginatos/química , Quitosano/química , Membranas Artificiales , Nanopartículas/química , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas
4.
Sci Eng Ethics ; 21(3): 595-617, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24891129

RESUMEN

Research with human-animal chimera raises a number of ethical concerns, especially when neural stem cells are transplanted into the brains of non-human primates (NHPs). Besides animal welfare concerns and ethical issues associated with the use of embryonic stem cells, the research is also regarded as controversial from the standpoint of NHPs developing cognitive or behavioural capabilities that are regarded as "unique" to humans. However, scientists are urging to test new therapeutic approaches for neurological diseases in primate models as they better mimic human physiology than all current animal models. As a response, various countries have issued reports on the topic. Our paper summarizes the ethical issues raised by research with human-animal brain chimeras and compares the relevant regulatory instruments and different recommendations issued in national reports from three important European research nations: Germany, Switzerland and the United Kingdom. We assess and discuss the focus and priorities set by the different reports, review various reasons for and perspectives on the importance of the brain in chimera research, and identify critical points in the reports that warrant further specification and debate.


Asunto(s)
Investigación Biomédica/ética , Encéfalo , Quimera , Células Madre Embrionarias , Ética , Neurociencias/ética , Trasplante de Células Madre , Animales , Cognición , Comparación Transcultural , Alemania , Humanos , Primates , Suiza , Reino Unido
5.
Food Funct ; 15(2): 663-675, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38108083

RESUMEN

The influence of co-oleogelators like lecithin or hydrogenated lecithin together with the addition of dispersed water droplets to modulate the microstructure and thus the physical properties of glyceryl stearate (GS)-corn oil oleogels was investigated by thermal profile, microstructure, hardness, and oil binding capacity (OBC). The addition of ß-carotene (ßC) was also assessed. With lecithin, crystallization and melting temperatures were reduced, resulting in less-ordered crystal networks with a lower hardness and OBC, while with hydrogenated lecithin, the opposite effect was observed. In the presence of water, oleogels became harder but more brittle. Finally, ßC acted as a crystal modifier increasing the hardness and OBC in the presence of lecithin, but decreased these parameters in hydrogenated lecithin-containing and water-filled oleogels. This study provides a better understanding on how the composition of GS-based oleogels can affect their physical properties.


Asunto(s)
Lecitinas , Compuestos Orgánicos , Lecitinas/química , Compuestos Orgánicos/química , Cristalización , Glicéridos , Agua/química
6.
Food Chem ; 456: 139978, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38870810

RESUMEN

This study explored how co-oleogelator type, concentration, and water addition affect lipid digestion and ß-carotene (ßC) bioaccessibility in corn oil oleogels. Oleogels containing 0.1% ßC, 20% glyceryl stearate (GS), with lecithin (L) or hydrogenated lecithin (HL) (at 0, 0.5, or 2.5%) and their water-filled counterparts (1% water) were examined. In vitro intestinal digestion revealed HL-oleogels experienced higher lipolysis due to their smaller crystal size enhancing surface area for lipase action, whereas L-oleogels presented lower digestibility, attributed to larger oil droplets and a minimized surface area. Water addition didn't significantly change lipid digestibility. ßC bioaccessibility was inversely related to co-oleogelator concentration, with L-oleogels demonstrating the largest decrease, likely due to less free fatty acids released for micelle formation. However, water-filled oleogels enhanced ßC bioaccessibility. These findings highlight that tailored microstructure in oleogels can control lipid digestion and ßC bioaccessibility, paving the way for designing efficient delivery systems for targeted nutrient delivery.

7.
Trauma Surg Acute Care Open ; 9(1): e001285, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38410756

RESUMEN

Background: Stress ulcers in patients with traumatic brain injury (TBI) and spinal cord injury (SCI) present significant morbidity and mortality risks. Despite the low reported stress ulcer rates, stress ulcer prophylaxis (SUP) is widely administered in neurocritical care. It was hypothesized that universal SUP administration may not be associated with reduced rates of complications across all neurocritical care patients. Methods: This retrospective study encompassed neurocritical care patients aged ≥18 with moderate or severe TBI or SCI, admitted to the intensive care unit (ICU) between October 2020 and September 2021, across six level I trauma centers. Exclusions included patients with an ICU stay <2 days, prior SUP medication use, and pre-existing SUP diagnoses. The primary exposure was SUP, with the primary outcome being clinically significant gastrointestinal bleeds (CSGIBs). Secondary outcomes included pneumonia and in-hospital mortality. Patients were stratified by admission Glasgow Coma Scale (GCS) groups. Results: Among 407 patients, 83% received SUP, primarily H2 receptor antagonists (88%) and proton pump inhibitors (12%). Patients on SUP were significantly younger, had lower admission GCS scores, higher Injury Severity Scores, longer ICU stays, and higher rates of mechanical ventilation than non-SUP patients. Overall, CSGIBs were rare (1%) and not significantly different between the SUP and non-SUP groups (p=0.06). However, CSGIBs exclusively occurred in patients with GCS scores of 3-8, and SUP was associated with a significantly lower rate of CSGIBs in this subgroup (p=0.03). SUP was also linked to significantly higher pneumonia rates in both GCS 3-8 and GCS 9-12 patients. Conclusions: This study highlights the low incidence of CSGIBs in neurocritical trauma patients and suggests potential benefits of SUP, particularly for those with severe neurological impairment. Nevertheless, the increased risk of pneumonia associated with SUP in these patients warrants caution. Further research is crucial to refine SUP guidelines for neurocritical care patients and inform optimal strategies. Level of evidence: Level III, retrospective.

8.
Food Chem ; 455: 139820, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38917656

RESUMEN

The emulsification potential of plant-based emulsifiers, that is, pea (PPI) and lentil (LPI) proteins (4%), corn arabinoxylans (CAX, 1%), and legume protein-arabinoxylan mixtures (4% proteins + 0.15 or 0.9% CAX), was evaluated by assessing: the surface tension and potential of emulsifiers, emulsifier antinutritional contents, emulsion droplet size, emulsion physical stability, and vitamin E bioaccessibility from 10% oil-in-water emulsions. Tween 80 (2%) was used as a control. All emulsions presented small droplet sizes, both fresh and upon storage, except 4% LPI + 0.9% CAX emulsion that exhibited bigger droplet sizes (d(4,3) of approximately 18.76 µm vs 0.59 µm for the control) because of droplet bridging. Vitamin E bioaccessibility from emulsions stabilized with the combination of 4% PPI and either 0.15% or 0.9% CAX (28 ± 4.48% and 28.42 ± 3.87%, respectively) was not significantly different from that of emulsions stabilized with Tween 80 (43.56 ± 3.71%), whereas vitamin E bioaccessibility from emulsions stabilized with individual emulsifiers was significantly lower.

9.
Dent J (Basel) ; 11(2)2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36826184

RESUMEN

This study analyzed the academic, sociodemographic, and labor conditions related to the quality of life (QOL) of orthodontics postgraduate students in Colombia. A mixed study (explanatory sequential design) was conducted. An online cross-sectional survey (n = 84; 64.3% females) was carried out with sociodemographic, academic, social support, health, labor, and QOL (WHOQOL-BREF) variables. Descriptive, bivariate analyses, and multivariate linear regression were performed. Focus groups (FGs) delved into aspects of relevance regarding QOL and determinants, through qualitative content analysis and triangulation of information. The median score in the four WHOQOL-BREF dimensions surpasses 50 points, with the highest score being in the psychological dimension (62.5 ± 16.7). According to the multivariate linear regression models, the variables significantly associated with QOL scores were playing sports, being married/living together, normal BMI, low social support, and medium/low socioeconomic status. The qualitative results explained the determinants of QOL in the personal, academic, and social dimensions of the participants. The discourses showed that the postgraduate course represents a resignification of their life, where their QOL is affected by the difficulties of their academic development, by the difficulty of reconciling the personal academic load with their affective, work, and social life, and by the stress they experience in their staff process. In conclusion, the participants' QOL was moderate and affected by different factors. The findings highlighted the importance of mental health promotion and well-being strategies in students of orthodontic postgraduate training programs in Colombia for improving QOL.

10.
Food Res Int ; 173(Pt 1): 113313, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37803624

RESUMEN

Essential oil (EO) nanoemulsions have been recently studied due to their antimicrobial properties. Nevertheless, little is known about their possible negative effect against human gut microorganisms during their passage though the gastrointestinal tract. This work studied the effect of digestible (corn oil) or non-digestible (paraffin oil) citral nanoemulsions against specific microorganisms of human microflora under in vitro digestion conditions. The use of a citral lipid carrier (paraffin oil or corn oil) decreased the nanoemulsion particle size and increased its stability after gastric conditions with regards to the pure citral nanoemulsions. Digestible nanoemulsions formulated with corn oil and citral presented a lower bactericidal activity against Lactobacillus acidophilus and Escherichia coli after being subjected to in vitro digestion conditions in comparison to the initial nanoemulsion. However, a non-digestible nanoemulsion formulated with paraffin oil and citral presented a similar antimicrobial activity against L. acidophilus and E. coli to the one of the initial nanoemulsion. This evidences that non-digestible nanoemulsions may entrap the citral in the lipid core and thus retaining its antimicrobial potential during their passage though the gastrointestinal tract. Hence, this work evidences the impact of the lipid carrier digestibility when formulating antimicrobial nanoemulsions on certain intestinal probiotic bacteria.


Asunto(s)
Antiinfecciosos , Aceite de Maíz , Humanos , Emulsiones , Escherichia coli , Digestión
11.
Food Res Int ; 173(Pt 2): 113455, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37803781

RESUMEN

Water-in-oil-in-water (W1/O/W2) emulsions offer the potential to deliver hydrophilic bioactive compounds into foods, yet their application remains limited due to their instability. Thus, the impact of lipid phase composition and state on the colloidal stability, in vitro lipid digestibility and chlorophyllin (CHL) bioaccessibility of W1/O/W2 emulsions before and after incorporation into whole milk was studied. Medium-chain triglyceride oil (MCT) was used as a liquid lipid phase and MCT with glyceryl stearate (GS) or pure hydrogenated palm oil (HPO) as gelled lipid phases. The lipid phase composition was crucial to forming W1/O/W2 emulsions. MCT or MCT+GS allowed the successful formation of W1/O/W2 emulsions, being more stable upon gastric conditions those formulated with MCT+GS than pure MCT. In contrast, the use of HPO led to phase separation, which was maintained after the gastric conditions. Regarding their lipid digestibility, W1/O/W2 emulsions formulated with MCT or MCT+GS were fully digested, whereas only 40% of the lipid was digested using HPO. In accordance, the CHL bioaccessibility was higher using MCT or MCT+GS than HPO. When co-digested with whole milk, the colloidal stability and lipid digestibility of the W1/O/W2 emulsions with MCT or MCT+GS were not altered, whereas the W1/O/W2 emulsion-HPO showed enhanced colloidal stability and lipid digestibility (57.71 ± 3.06%), due to the surface-active properties of milk protein. The present study provides useful information to develop stable functional foods enriched with hydrophilic bioactive compounds by using W1/O/W2 emulsions.


Asunto(s)
Clorofilidas , Emulsiones , Glicéridos , Agua
12.
Colloids Surf B Biointerfaces ; 227: 113349, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37207385

RESUMEN

The present work aimed at studying the in vitro digestion fate of κ-carrageenan (KC) or agar (AG) emulsion gels (EG), and KC oil-filled aerogels (OAG) in terms of their structural changes, lipolysis kinetics and curcumin bioaccessibility. On the one hand, both EG and aerogels showed large (70-200 µm) and heterogeneous particles after gastric conditions, indicating the release of bulk oil and gelled material. Nonetheless, this material release in the stomach phase was lower in the case of EG-AG and OAG-KC compared to EG-KC. After small intestinal conditions, EG and oil-filled aerogels presented a wide range of particle sizes probably due to the presence of undigested lipid material, gelled structures, as well as lipid digestion products. For the most part, adding curcumin to the structures' lipid phase did not cause of the structural modifications that occurred at the different in vitro digestion phases. On the other hand, the lipolysis kinetics was different depending on the type of structure. Amongst emulsion-gels, those formulated with κ-carrageenan presented a slower and lower lipolysis kinetics compared to those formulated with agar, which could be attributed to their higher initial hardness. Overall, the addition of curcumin in the lipid phase decreased the lipolysis in all the structures, which evidenced its interference in the lipid digestion process. The curcumin bioaccessibility reached high values (≈ 100 %) for all the studied structures, presenting a high solubility in intestinal fluids. This work unravels the implications of microstructural changes of emulsion-gels and oil-filled aerogels during digestion and their impact on their digestibility and subsequent functionality.


Asunto(s)
Curcumina , Curcumina/química , Emulsiones/química , Carragenina , Agar , Polisacáridos , Lípidos/química , Digestión , Geles , Tamaño de la Partícula
13.
J Intell ; 11(9)2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37754910

RESUMEN

The Attentional Networks Test for Interactions and Vigilance-executive and arousal components (ANTI-Vea) is a computerized task of 32 min duration in the standard format. The task simultaneously assesses the main effects and interactions of the three attentional networks (i.e., phasic alertness, orienting, and executive control) and two dissociated components of vigilance with reasonable reliability (executive and arousal vigilance). We present this free and publicly accessible resource (ANTI-Vea-UGR; https://anti-vea.ugr.es/) developed to easily run, collect, and analyze data with the ANTI-Vea (or its subtasks measuring some attentional and/or vigilance components embedded in the ANTI-Vea). Available in six different languages, the platform allows for the adaptation of stimulus timing and procedure to facilitate data collection from different populations (e.g., clinical patients, children). Collected data can be freely downloaded and easily analyzed with the provided scripts and tools, including a Shiny app. We discuss previous evidence supporting that attention and vigilance components can be assessed in typical lab conditions as well as online and outside the laboratory. We hope this tutorial will help researchers interested in measuring attention and vigilance with a tool useful to collect data from large sample sizes and easy to use in applied contexts.

14.
Food Chem ; 387: 132934, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35421652

RESUMEN

In the current study, the production and characterization of novel solid lipid nanoparticles (SLNs) using safe/low-cost natural beeswax (BW) and propolis wax (PW) and by the simple and inexpensive assay of spontaneous emulsification were studied. To fabricate SLNs, the optimum levels of surfactant/oil ratio (SOR), stirring speed, and time were obtained based on minimum particle size (PS) and polydispersity index (PDI). Therefore, the optimal conditions to produce PW and BW nanoparticles were SOR of 1.26 and 2 under stirring speed of 1050 rpm for 20 min, leading to PS of 21.9 and 23.2 nm, respectively. The contact angle of 73.7° and 62.9° for BW and PW SLNs respectively, showed suitable hydrophilicity to stabilize oil-in-water (O/W) Pickering emulsions. Temperatures over 70 °C led to a drastic increment of PS in both types of SLNs. Upon nanoparticles drying, the utilization of cryoprotectants could cause less aggregation and better reconstitution.


Asunto(s)
Nanopartículas , Própolis , Emulsiones , Liposomas , Tamaño de la Partícula , Tensoactivos , Ceras
15.
Food Chem ; 387: 132877, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35397271

RESUMEN

Agar and κ-carrageenan emulsion gels and oil-filled aerogels were investigated as curcumin carriers and their structure and mechanical properties, as well as their structural changes upon in vitro gastrointestinal digestion were characterized. Agar emulsion gels presented stiffer behaviour, with smaller and more homogeneous oil droplets (ϕ âˆ¼ 12 µm) than those from κ-carrageenan (ϕ âˆ¼ 243 µm). The structure of κ-carrageenan gels was characterized by the presence of rigid swollen linear chains, while agar produced more branched networks. After simulated gastrointestinal digestion bile salt lamellae/micelles (∼5 nm) and larger vesicles of partially digested oil (Rg âˆ¼ 20-50 nm) were the predominant structures, being their proportion dependent of the polysaccharide type and the physical state of the gel network. The presence of curcumin induced the formation of larger vesicles and limited the formation of mixed lamellae/micelles.


Asunto(s)
Curcumina , Agar/química , Carragenina , Curcumina/química , Digestión , Emulsiones/química , Geles/química , Micelas
16.
Food Chem ; 369: 130850, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34461510

RESUMEN

Recent studies have shown that mild to moderate iron chlorosis can have positive effects on grape quality potential, including volatile profile. The main objective of this work was to investigate, for the first time, how moderate iron stress in grapevines affects the presence of volatile organic compounds (VOCs) in wines. The study was carried out during 2018-2019 seasons, in 20 Tempranillo vineyard subzones with different degree of iron deficiency, located in Ribera del Duero (North-Central Spain). The results showed that moderate iron stress increased in wines the concentrations of VOCs associated with floral notes, such as 2-phenylacetaldehyde, 2-phenylethanol and 2-phenylethyl acetate, while reducing the presence of C6-alcohols, responsible for green-herbaceous aroma. A favourable reduction of pH and a betterment of parameters related to colour were detected in wines from iron deficient subzones. Chlorosis incidence was associated to improvements in wine sensory attributes as layer intensity, black fruit and aroma intensity.


Asunto(s)
Anemia Hipocrómica , Vitis , Compuestos Orgánicos Volátiles , Vino , Granjas , Frutas/química , Humanos , Hierro , Odorantes/análisis , Compuestos Orgánicos Volátiles/análisis , Vino/análisis
17.
Foods ; 10(9)2021 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-34574304

RESUMEN

In this study, the digestibility of oil-in-water (O/W) emulsions using low methoxyl pectin (LMP) as surfactant and in combination with avocado peel (AP) or seed (AS) extracts was assessed, in terms of its free fatty acid (FFA) release and the phenolic compound (PC) bioaccessibility. With this purpose, AP and AS were characterized by UPLC-ESI-MS/MS before their incorporation into O/W emulsions stabilized using LMP. In that sense, AP extract had a higher content of PCs (6836.32 ± 64.66 mg/100 g of extract) compared to AS extract (1514.62 ± 578.33 mg/100 g of extract). Both extracts enhanced LMP's emulsifying properties, leading to narrower distributions and smaller particle sizes compared to those without extracts. Similarly, when both LMP and the extracts were present in the emulsions the FFA release significantly increased. Regarding bioaccessibility, the PCs from the AS extracts had a higher bioaccessibility than those from the AP extracts, regardless of the presence of LMP. However, the presence of LMP reduced the bioaccessibility of flavonoids from emulsions containing either AP or AS extracts. These results provide new insights regarding the use of PC extracts from avocado peel and seed residues, and the effect of LMP on emulsion digestibility, and its influence on flavonoids bioaccessibility.

18.
Food Funct ; 12(2): 840-851, 2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33404565

RESUMEN

Carotenoids are lipophilic compounds that provide important health-related benefits for human body functions. However, they have low water solubility and chemical stability, hence their incorporation in aqueous-based foods requires the use of emulsion-based lipid carriers. This work aimed at elucidating whether their inclusion in emulsion-based Solid Lipid Nanoparticles (SLNs) can provide a protective effect against ß-carotene degradation under different environmental conditions in comparison to liquid lipid nanoemulsions. Glyceryl Stearate (GS) was mixed with Medium Chain Trygliceride (MCT) oil to formulate SLNs. SLNs presented a significantly enhanced ß-carotene retention and a slower ß-carotene degradation kinetics at increasing storage temperature, acidic conditions and light exposure. In fact, SLNs formulated with 5% GS in the lipid phase and stored at 4 °C and pH 7 retained almost 70% of the initially encapsulated ß-carotene after 55 days of storage, while it was completely degraded when it was encapsulated in liquid nanoemulsions. Moreover, it was observed that the solid lipid type affects the protective effect that SLNs may confer to the encapsulated lipophilic bioactives. Saturated long chain triglycerides, such as hydrogenated palm oil (HPO) presented slower and lower ß-carotene degradation kinetics in comparison to solid lipids composed of MCT, such as Coconut Oil (CNUT) or MCT + 5% of GS in the lipid phase. This work evidences that the incorporation of lipophilic bioactive compounds, such as ß-carotene, into SLNs slows down their degradation kinetics which might be attributed to a reduced diffusion of the oxidative species due to the lipid crystalline structure.


Asunto(s)
Lípidos/farmacología , Nanopartículas/química , beta Caroteno/química , Portadores de Fármacos/química , Concentración de Iones de Hidrógeno , Lípidos/química , Temperatura
19.
Curr Pharm Biotechnol ; 22(5): 636-645, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32679017

RESUMEN

BACKGROUND: Cancer is one of the leading cause of death worldwide. Besides current therapies and treatments to counter cancer, new alternatives are required to diminish the cell proliferation of oncogenic processes. METHODS: One of the most promissory therapy includes the use of blue scorpion venom as a specific cytotoxic agent to kill tumoral cells, including Glioblastoma multiforme. OBJECTIVES: We show evidence of the cytotoxic effect of blue scorpion venom in a cellular model of Glioblastoma multiforme. RESULTS: Our results demonstrate that 50 µg/ml of scorpion venom is capable to diminish the viability of Glioblastoma populations. CONCLUSION: It is possible that the action mechanism could be associated with a loss of membrane integrity. Additionally, some metalloproteinases as MMP2 and MMP9 may also participate in the potential action mechanism.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Venenos de Escorpión/farmacología , Animales , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Escorpiones
20.
Food Chem ; 311: 126024, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-31855778

RESUMEN

Solid lipid nanoparticles (SLNs) are emulsion-based carriers of lipophilic bioactive compounds. However, their digestibility may be affected by the solid lipid phase composition. Hence, the aim of this work was to study the in vitro lipolysis kinetics as well as the relationship between the lipid digestion, micelle fraction composition and ß-carotene bioaccessibility of SLNs with different solid lipids, being blends of medium chain triglyceride (MCT) oil, glyceryl stearate (GS) or hydrogenated palm oil (HPO) as compared to liquid lipid nanoparticles (LLNs) with pure MCT. SLNs formulated with GS were fully digested, similarly to LLNs. However, HPO-containing SLNs presented slower lipolysis kinetics during the intestinal phase at increasing HPO concentration. Despite this, HPO-SLNs showed higher ß-carotene bioaccessibility, which was related to the higher amount of monounstaturated free fatty acids in the micelle fraction. Thus, this work provides valuable insight for designing delivery systems of bioactive compounds with optimal functionality.


Asunto(s)
Lípidos/química , Lipólisis/efectos de los fármacos , Nanopartículas/química , beta Caroteno/farmacocinética , Digestión/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Glicéridos/metabolismo , Cinética , Micelas , beta Caroteno/metabolismo
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