Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 344
Filtrar
Mais filtros

Medicinas Complementares
Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Biomater Adv ; 160: 213830, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38552500

RESUMO

Cancer, namely breast and prostate cancers, is the leading cause of death in many developed countries. Controlled drug delivery systems are key for the development of new cancer treatment strategies, to improve the effectiveness of chemotherapy and tackle off-target effects. In here, we developed a biomaterials-based wireless electrostimulation system with the potential for controlled and on-demand release of anti-cancer drugs. The system is composed of curcumin-loaded poly(3,4-ethylenedioxythiophene) nanoparticles (CUR/PEDOT NPs), encapsulated inside coaxial poly(glycerol sebacate)/poly(caprolactone) (PGS/PCL) electrospun fibers. First, we show that the PGS/PCL nanofibers are biodegradable, which allows the delivery of NPs closer to the tumoral region, and have good mechanical properties, allowing the prolonged storage of the PEDOT NPs before their gradual release. Next, we demonstrate PEDOT/CUR nanoparticles can release CUR on-demand (65 % of release after applying a potential of -1.5 V for 180 s). Finally, a wireless electrostimulation platform using this NP/fiber system was set up to promote in vitro human prostate cancer cell death. We found a decrease of 67 % decrease in cancer cell viability. Overall, our results show the developed NP/fiber system has the potential to effectively deliver CUR in a highly controlled way to breast and prostate cancer in vitro models. We also show the potential of using wireless electrostimulation of drug-loaded NPs for cancer treatment, while using safe voltages for the human body. We believe our work is a stepping stone for the design and development of biomaterial-based future smarter and more effective delivery systems for anti-cancer therapy.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Glicerol/análogos & derivados , Nanopartículas , Poliésteres , Polímeros , Tecnologia sem Fio , Humanos , Compostos Bicíclicos Heterocíclicos com Pontes/química , Nanopartículas/química , Polímeros/química , Poliésteres/química , Curcumina/administração & dosagem , Curcumina/química , Glicerol/química , Masculino , Neoplasias da Próstata/terapia , Antineoplásicos/administração & dosagem , Decanoatos/química , Nanofibras/química , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Linhagem Celular Tumoral , Estimulação Elétrica/instrumentação , Estimulação Elétrica/métodos
2.
Food Chem ; 443: 138596, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38301566

RESUMO

Enzymatic glycerolysis is a biotechnological process for structuring vegetable oils. This study investigates the kinetics of glycerolysis of peanut oil and explores the potential of the resulting structured oil to enhance the physical stability of water-in-oil emulsions. Using a 1:1 glycerol-to-oil molar ratio and 4 % lipase B from Candida antarctica as a catalyst, the reaction was conducted at 65 °C with stirring at 400 rpm. Acylglyceride fractions changes were quantified through NMR and DSC. Fat crystal formation was observed using scanning electron microscopy. The results revealed a first-order decay pattern, converting triglycerides into monoacylglycerides and diacylglycerides in less than 16 h. Subsequently, water-in-oil emulsions prepared with glycerolized oil showed augmented stability through multiple light scattering techniques and visual assessment. The structured oils effectively delayed phase separation, highlighting the potential of glycerolysis in developing vegetable oil-based emulsions with improved functional properties and reduced saturated fatty acid content.


Assuntos
Óleos de Plantas , Água , Óleos de Plantas/química , Emulsões , Óleos , Glicerol/química , Ácidos Graxos/química
3.
Int J Biol Macromol ; 263(Pt 1): 130165, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367784

RESUMO

This work reports on the extraction and characterization of the behavior of starch from residues of several potato varieties (Criolla, Sabanera and Pastusa) of Colombian origin from the Andean region using different techniques and the evaluation of the effect of citric acid (CA) on the grain morphology. Additionally, films were produced with each one of the extracted starches and glycerol. Pastusa variety starch shows a higher granule size than the other varieties and Pastusa starch shows lower amylose content compared to Sabanera and Criolla. Criolla and Pastusa starches exhibit more thermal stability than Sabanera starch. Starch-glycerol films were also produced using the cast solving method. The films were mechanically analyzed by tensile test and the barrier properties were assessed by water vapor permeability (WVP). The tensile strength of the films varied in the 2.0-2.4 MPa range, while the elongation at break was comprised between 25 and 32 %. With regard to water vapor permeability, the obtained values fall within the 4-7 × 10-10 g m-1 s-1 Pa-1 range. It was observed that the thickness of the films and the protein content affected water vapor permeability, increasing this value at higher levels of thickness.


Assuntos
Filmes Comestíveis , Solanum tuberosum , Amido/química , Solanum tuberosum/química , Vapor , Glicerol/química , Colômbia , Permeabilidade , Resistência à Tração
4.
Compr Rev Food Sci Food Saf ; 22(6): 4282-4301, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37583303

RESUMO

Polyglycerol polyricinoleate (PGPR) is a synthetic food additive containing a complex mixture of various esters. In recent years, there has been a growing trend to use PGPR-stabilized water-in-oil (W/O) emulsions to replace fat in order to produce low-calorie food products. In this respect, it is essential to comprehensively characterize the PGPR molecular species composition, which might enable to reduce its required amount in emulsions and foods based on a better understanding of the structure-activity relationship. This review presents the recent research progress on the characterization and quantitative analysis of PGPR. The influencing factors of the emulsifying ability of PGPR in W/O emulsions are further illustrated to provide new insights on the total or partial replacement of PGPR. Moreover, the latest progress on applications of PGPR in food products is described. Current studies have revealed the complex structure of PGPR. Besides, recent research has focused on the quantitative determination of the composition of PGPR and the quantification of the PGPR concentration in foods. However, research on the quantitative determination of the (poly)glycerol composition of PGPR and of the individual molecular species present in PGPR is still limited. Some natural water- or oil-soluble surfactants (e.g., proteins or lecithin) have been proven to enable the partial replacement of PGPR in W/O emulsions. Additionally, water-dispersible phytosterol particles and lecithin have been successfully used as a substitute of PGPR to create stable W/O emulsions.


Assuntos
Glicerol , Lecitinas , Glicerol/química , Ácidos Ricinoleicos/química , Emulsões/química , Água/química
5.
Ultrason Sonochem ; 95: 106354, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36898248

RESUMO

The study aimed to evaluate the effect of ultrasonic pretreatment on the transesterification of lard with glycerol monolaurate (GML) using Lipozyme TL IM to synthesize diacylglycerol (DAG), and the physicochemical properties of lard, GML, ultrasonic-treated diacylglycerol (named U-DAG), purified ultrasonic-treated diacylglycerol obtained by molecular distillation (named P-U-DAG), and without ultrasonic-treated diacylglycerol (named N-U-DAG) were analyzed. The optimized ultrasonic pretreatment conditions were: lard to GML mole ratio 3:1, enzyme dosage 6 %, ultrasonic temperature 80 °C, time 9 min, power 315 W. After ultrasonic pretreatment, the mixtures reacted for 4 h in a water bath at 60 °C, the content of DAG reached 40.59 %. No significant variations were observed between U-DAG and N-U-DAG in fatty acids compositions and iodine value, while P-U-DAG had lower unsaturated fatty acids than U-DAG. Differential scanning calorimetry analysis showed that the melting and crystallization properties of DAGs prepared by ultrasonic pretreatment significantly differed from lard. FTIR spectra noted transesterification reaction from lard and GML with and without ultrasonic pretreatment would not change the structure of lard. However, thermogravimetric analysis proved that N-U-DAG, U-DAG, and P-U-DAG had lower oxidation stability than lard. The higher the content of DAG, the faster the oxidation speed.


Assuntos
Gorduras na Dieta , Diglicerídeos , Diglicerídeos/química , Gorduras na Dieta/análise , Catálise , Glicerol/química
6.
Int J Biol Macromol ; 227: 938-951, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36563809

RESUMO

Sustainable and "green" technologies, such as cold plasma are gaining attention in recent times for improving the functional properties of hydrocolloids. Chemical modifications of hydrocolloids require several chemicals and solvents, which are not environment-friendly. The major objective of the study was to understand the impact of plasma treatment (170-230 V|15 min) on the rheology of film-forming solutions (FFS) and the barrier properties of pectin films. The film-forming properties of plasma-treated pectin were investigated in the presence of two plasticizers, namely, glycerol and polyethylene glycol (PEG) 400. The effects of cross-linking by CaCl2 on the rheology of FFS and barrier properties of the films were discussed. A voltage-dependent decrease in the apparent viscosity of FFS was observed. The viscoelastic properties of the FFS were enhanced due to cross-linking. Glycerol exhibited a better plasticizing effect than PEG. Cross-linking and increasing voltage synergistically contributed towards lower oxygen and carbon dioxide transmission rates. The moisture sorption rate and capacity of the films increased with the voltage of the treatment. The resistance to extension of the films made from glycerol and PEG decreased with voltage, with no significant change in extensibility. On the other hand, the cross-linking by Ca2+ and plasma treatment enhanced the resistance to extension for the films made from both the plasticizers. While the increasing hydrophilicity and opacity of the films were a major drawback of plasma modification, the increase in UV barrier property of the films was an advantage of the modification.


Assuntos
Malus , Gases em Plasma , Glicerol/química , Plastificantes/química , Pectinas/química , Reologia
7.
Int J Biol Macromol ; 213: 1068-1077, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35697167

RESUMO

Sweet potato (Ipomonea batatas Lam) is easily damaged due to its thin skin, which is limited in shelf life and causes enormous economic losses in the food industry. A new type of safe, non-toxic, and edible antibacterial functional film was developed with sodium alginate (2.5 %), gum arabic (1 %), glycerol (2 %), and natamycin as an antimicrobial agent in this study. The physical and antibacterial properties of films, such as thickness, chromaticity, water vapor permeability, tensile strength, and elongation at break, were studied. Furthermore, the antibacterial film was applied in the preservation of sweet potatoes. The results showed that natamycin emulsion had good compatibility with sodium alginate. Besides reducing the transparency of the composite membrane, the mechanical properties, barrier properties, and thermal stability of the composite film were significantly enhanced by the addition of natamycin prepared by a pH-cycle method. When the concentration of natamycin in the membrane solution reached 40 µg/mL or more, the antibacterial film had a noticeable inhibitory effect on the growth of molds, and yeasts, significantly enhancing the bacteriostatic effect of the base film. During the sweet potatoes storage, the water content, total starch content, Vc content, and flavonoid glycoside content of sweet potato showed a downward trend. However, the treatment of antibacterial film containing natamycin could slow down the physiological and quality changes of sweet potatoes during conventional storage, and the sweet potatoes still had good processing quality after 120 days of storage.


Assuntos
Filmes Comestíveis , Ipomoea batatas , Solanum tuberosum , Alginatos/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Embalagem de Alimentos , Glicerol/química , Goma Arábica , Natamicina , Permeabilidade
8.
J Phys Chem B ; 126(4): 890-905, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35076242

RESUMO

The dynamics of the organic components of the deep eutectic solvent (DES) glyceline are analyzed using an array of complementary nuclear magnetic resonance (NMR) methods. Fast-field cycling 1H relaxometry, pulsed field gradient diffusion, nuclear overhauser effect spectroscopy (NOESY), 13C NMR relaxation, and pressure-dependent NMR experiments are deployed to sample a range of frequencies and modes of motion of the glycerol and choline components of the DES. Generally, translational and rotational diffusion of glycerol are more rapid than those of choline while short-range rotational motions observed from 13C relaxation indicate slow local motion of glycerol at low choline chloride (ChCl) content. The rates of glycerol and choline local motions become more similar at higher ChCl. This result taken together with pressure-dependent NMR studies show that the addition of ChCl makes it easier to disrupt glycerol packing. Finally, a relatively slow hydroxyl H-exchange process between glycerol and choline protons is deduced from the data. Consistent with this, NOESY results indicate relatively little direct H-bonding between glycerol and choline. These results suggest that the glycerol H-bonding network is disrupted as choline is added, but primarily in regions where there is intimate mixing of the two components. Thus, the local dynamics of most of the glycerol resembles that of pure glycerol until substantial choline chloride is present.


Assuntos
Colina , Glicerol , Colina/química , Difusão , Glicerol/química , Espectroscopia de Ressonância Magnética , Solventes/química
9.
Bioprocess Biosyst Eng ; 45(4): 721-732, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35076754

RESUMO

This study focuses on the potential of Rhodotorula mucilaginosa CCT 7688 in simultaneous production of lipids and carotenoids in agroindustrial byproduct-based media and specially aims at establishing a process condition that guarantees high concentrations of both bioproducts, i.e., a carotenoid-rich microbial oil with potential economic value and health benefits attributed to carotenoids and fatty acids. Four different combinations of cultivation modes (batch and fed-batch) and alternative substrates (crude glycerol, sugarcane molasses and corn steep liquor) were tested. The M2-B assay, which comprises the use of an agroindustrial byproduct-based medium without any supplementation (70 g L-1 sugarcane molasses and 3.4 g L-1 corn steep liquor) and batch mode, was selected as the most promising one to produce both compounds. Total carotenoid production and total lipid content were 1794.2 µg L-1 and 43.2% (w/w), respectively, after 144 h of cultivation. The fatty acid profile showed predominance of oleic acid (69.9%) and palmitic acid (23.2%). Thus, R. mucilaginosa CCT 7688 may be used in simultaneous production of lipids and carotenoids successfully; its fatty acid profile is similar to that found in olive oil. Both compounds are economically interesting and have great possibility of future commercial applications.


Assuntos
Carotenoides , Rhodotorula , Biocombustíveis , Biomassa , Meios de Cultura , Glicerol/química , Melaço , Ácido Oleico
10.
J Biomater Sci Polym Ed ; 33(4): 443-464, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34641773

RESUMO

In this study, a novel biopolymer based on poly(glycerol sebacic)-urethane (PGS-U) and its nanocomposites containing Cloisite@30B were synthesized by facile approach in which the crosslinking was created by aliphatic hexamethylene diisocyanate (HDI) at room temperature and 80 °C. Moreover, metronidazole and tetracycline drugs were selected as target drugs and loaded into PGSU based nanocomposites. A uniform and continuous microstructure with smooth surface is observed in the case of pristine PGS-U sample. The continuity of microstructure is observed in the case of all bionanocomposites. XRD result confirmed an intercalated morphology for PGSU containing 5 wt% of clay nanoparticles with a d-spacing 3.4 nm. The increment of nanoclay content up to 5%, the ultimate tensile stress and elastic modulus were obtained nearly 0.32 and 0.83 MPa, which the latter was more than eight-fold than that of pristine PGS-U. A sustained release for both dugs was observed by 200 h. The slowest and controlled drug release rate was determined in the case of PGSU containing 5 wt% clay and cured at 80 °C. A non-Fickian diffusion can be concluded in the case of tetracycline release via PGS-U/nanoclay bionanocomposites, while a Fickian process was detected in the case of metronidazole release by PGS-U/nanoclay bionanocomposites. As a result, the designed scaffold showed high flexibility, which makes it an appropriate option for utilization in the treatment of periodontal disease.


Assuntos
Glicerol , Nanocompostos , Argila , Decanoatos/química , Sistemas de Liberação de Medicamentos , Glicerol/análogos & derivados , Glicerol/química , Metronidazol , Nanocompostos/química , Polímeros , Tetraciclina , Uretana
11.
Molecules ; 26(21)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34771028

RESUMO

Helichrysum italicum is a medicinal plant from the Mediterranean area, widely used in traditional medicine for its anti-inflammatory, antibacterial and antioxidant properties and for its preventive effects on microcirculation diseases. Due to these properties, it finds large applications in cosmetic, food and pharmaceutical fields. Additionally, hydroalcoholic extracts and mother tinctures based on H. italicum represent products with a high commercial value, widely distributed not only in drug stores but also on on-line markets. The different extraction procedures used can greatly affect the fingerprints of the extracts, resulting in a different qualitative or quantitative profile of the chemical constituents responsible for biological activity. The aim of the present study was to characterize the composition of bioactive compounds present in water-ethanol and glycerol extracts of H. italicum derived food supplements. Metabolite profiles of the extracts were obtained by 1H NMR experiments and data were processed by multivariate statistical analysis to highlight differences in the extracts and to evidence the extracts with the highest concentrations of bioactive metabolites. In detail, this work highlights how derived food supplements of H. italicum obtained using ethanol-water mixtures ranging from 45% to 20% of ethanol represent the products with the highest amount of both primary (amino acids) and secondary metabolites including 3,4-dicaffeoylquinic acid (9), chlorogenic acid (10), 3,5-dicaffeoylquinic acid (11), and kaempferol 3-O-glucopyranoside (12). Moreover, it is evident that the use of an ethanol-water mixture 20:80 is the most suitable method to afford the highest number of phenolic compounds, while food-derived supplements obtained by glycerol extraction are characterized by a high amount of ß-glucose and α-glucose and a low content of phenolic compounds.


Assuntos
Suplementos Nutricionais/análise , Helichrysum/metabolismo , Metabolômica , Extratos Vegetais/metabolismo , Glicerol/química , Helichrysum/química , Extratos Vegetais/análise , Espectroscopia de Prótons por Ressonância Magnética
12.
Chem Commun (Camb) ; 57(82): 10661-10674, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34585190

RESUMO

Developing (chemo)enzymatic cascades is very attractive for green synthesis, because they streamline multistep synthetic processes. In this Feature Article, we have summarized the recent advances in in vitro or whole-cell cascade reactions with a focus on the use of renewable bio-based resources as starting materials. This includes the synthesis of rare sugars (such as ketoses, L-ribulose, D-tagatose, myo-inositol or aminosugars) from readily available carbohydrate sources (cellulose, hemi-cellulose, starch), in vitro enzyme pathways to convert glucose to various biochemicals, cascades to convert 5-hydroxymethylfurfural and furfural obtained from lignin or xylose into novel precursors for polymer synthesis, the syntheses of phenolic compounds, cascade syntheses of aliphatic and highly reduced chemicals from plant oils and fatty acids, upgrading of glycerol or ethanol as well as cascades to transform natural L-amino acids into high-value (chiral) compounds. In several examples these processes have demonstrated their efficiency with respect to high space-time yields and low E-factors enabling mature green chemistry processes. Also, the strengths and limitations are discussed and an outlook is provided for improving the existing and developing new cascades.


Assuntos
Carboidratos/síntese química , Animais , Catálise , Etanol/química , Ácidos Graxos/química , Furaldeído/análogos & derivados , Furaldeído/química , Glicerol/química , Química Verde , Humanos , Lignina/química , Óleos de Plantas/química
13.
Microb Cell Fact ; 20(1): 185, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34556134

RESUMO

BACKGROUND: The anaerobic production of rhamnolipids is significant in research and application, such as foamless fermentation and in situ production of rhamnolipids in the anoxic environments. Although a few studies reported that some rare Pseudomonas aeruginosa strains can produce rhamnolipids anaerobically, the decisive factors for anaerobic production of rhamnolipids were unknown. RESULTS: Two possible hypotheses on the decisive factors for anaerobic production of rhamnolipids by P. aeruginosa were proposed, the strains specificity of rare P. aeruginosa (hypothesis 1) and the effect of specific substrates (hypothesis 2). This study assessed the anaerobic growth and rhamnolipids synthesis of three P. aeruginosa strains using different substrates. P. aeruginosa strains anaerobically grew well using all the tested substrates, but glycerol was the only carbon source that supported anaerobic production of rhamnolipids. Other carbon sources with different concentrations still failed for anaerobic production of rhamnolipids by P. aeruginosa. Nitrate was the excellent nitrogen source for anaerobic production of rhamnolipids. FTIR spectra analysis confirmed the anaerobically produced rhamnolipids by P. aeruginosa using glycerol. The anaerobically produced rhamnolipids decreased air-water surface tension to below 29.0 mN/m and emulsified crude oil with EI24 above 65%. Crude glycerol and 1, 2-propylene glycol also supported the anaerobic production of rhamnolipids by all P. aeruginosa strains. Prospects and bottlenecks to anaerobic production of rhamnolipids were also discussed. CONCLUSIONS: Glycerol substrate was the decisive factor for anaerobic production of rhamnolipids by P. aeruginosa. Strain specificity resulted in the different anaerobic yield of rhamnolipids. Crude glycerol was one low cost substrate for anaerobic biosynthesis of rhamnolipids by P. aeruginosa. Results help advance the research on anaerobic production of rhamnolipids, deepen the biosynthesis theory of rhamnolipids and optimize the anaerobic production of rhamnolipids.


Assuntos
Glicerol/farmacologia , Glicolipídeos/biossíntese , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/metabolismo , Anaerobiose , Carbono/metabolismo , Fermentação , Glicerol/química , Glicerol/metabolismo , Nitrogênio/metabolismo , Petróleo , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética , Tensoativos/farmacologia
14.
Carbohydr Polym ; 271: 118433, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34364573

RESUMO

The purpose of this study was to use hydroxypropyl-ß-cyclodextrin (HP-ß-CD) as a novel carrier in solid SNEDDS and solid dispersions to enhance the solubility and oral bioavailability of poorly water-soluble dexibuprofen. The novel dexibuprofen-loaded solid SNEDDS was composed of dexibuprofen, corn oil, polysorbate 80, Cremophor® EL, and HP-ß-CD at a weight ratio of 45/35/50/15/100. This solid SNEDDS spontaneously formed a nano-emulsion with a size of approximately 120 nm. Unlike the conventional solid SNEDDS prepared with colloidal silica as a carrier, this dexibuprofen-loaded solid SNEDDS exhibited a spherical structure. Similar to the dexibuprofen-loaded solid dispersion prepared with HP-ß-CD, the transformation of the crystalline drug to an amorphous state with no molecular interactions were observed in the solid SNEDDS. Compared to the solid dispersion and dexibuprofen powder, solid SNEDDS significantly enhanced drug solubility and AUC. Therefore, HP-ß-CD is a novel potential carrier in SNEDDS for improving the oral bioavailability of dexibuprofen.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/química , Portadores de Fármacos/química , Emulsões/química , 2-Hidroxipropil-beta-Ciclodextrina/farmacocinética , Animais , Óleo de Milho/química , Óleo de Milho/farmacocinética , Portadores de Fármacos/farmacocinética , Emulsões/farmacocinética , Glicerol/análogos & derivados , Glicerol/química , Glicerol/farmacocinética , Ibuprofeno/análogos & derivados , Ibuprofeno/química , Ibuprofeno/farmacocinética , Masculino , Polissorbatos/química , Polissorbatos/farmacocinética , Ratos Sprague-Dawley , Solubilidade
15.
J Food Sci ; 86(10): 4539-4553, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34431096

RESUMO

Persimmon is among the fruits with a significant postharvest loss over the last few years. Thus, it is important to investigate new technical feasibilities to obtain products with higher added value from this fruit. In this study persimmon puree films (Diospyros kaki L.) incorporated with glycerol and pectin by casting technique were formulated using a Plackett-Burman design and characterized. The puree showed high carbohydrate content (175.70 g/kg). In descending order, fructose, glucose, and maltohexaose were the sugars found in persimmon. All the independent variables studied-puree concentration, pectin, glycerol, and temperature-statistically influenced the tensile strength (0.75-1.30 MPa), elongation at break (17.69-26.02%), and Young's modulus (3.34-10.94 MPa) of the films. Water solubility ranged from 68.80% to 80.86%, which were very similar to other films based on puree fruit in the literature. Samples presented high vapor permeability (5.77-6.63 × 10-6 g/h/m/Pa) when compared to biodegradable films. Scanning electron microscopy showed smooth surfaces and good plasticizer dispersion. The colorimetric coordinates indicated the films are reddish and yellowish, giving them an orange-ish visual aspect. The films exhibited antimicrobial activity, especially against Escherichia coli and Staphylococcus aureus. These results indicate that the developed films might be a good candidate for antimicrobial food packaging improving food quality and safety. PRACTICAL APPLICATION: The production of fruit-film packaging with functional and biodegradable characteristics might reduce postharvest loss of fruit and have the potential to develop active food packaging. In this sense, this study is in line with precepts of the circular economy, once it takes advantage of exceeded resources that would be discarded by generating biodegradable films which can be used as edible packaging. Furthermore, given the antimicrobial potential of the films developed, they might be applied as active packaging to improve food safety and extend shelf life.


Assuntos
Diospyros , Embalagem de Alimentos , Glicerol , Pectinas , Antibacterianos/farmacologia , Diospyros/química , Embalagem de Alimentos/métodos , Frutas/química , Glicerol/química , Pectinas/química , Permeabilidade , Resistência à Tração
16.
Int J Biol Macromol ; 186: 759-769, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34271051

RESUMO

The present work aims to fabricate the genipin-crosslinked alkaline soluble polysaccharides-whey protein isolate conjugates (G-AWC) to stabilize W/O/W emulsions for encapsulation and delivery of grape seed proanthocyanidins (GSP). After crosslinking reaction, the molecular weight was increased and surface hydrophobicity was decreased. Then, the G-AWC and polyglycerol polyricinoleate (PGPR, a lipophilic emulsifier) were employed to prepare a GSP-loaded W/O/W emulsion with the addition of gelatin and sucrose in W1 phase via a two-step procedure. Creamed emulsion could be fabricated at W1/O volume fraction (Φ) of 10%-70% and further increased Φ to 75% or even up to 90% could obtain gel-like emulsion with notably elastic behaviors. In the W1/O/W2 emulsion with Φ of 80%, the encapsulation efficiency (EE) of GSP reached up to 95.86%, and decreased by ca. 10% after a week of storage. Moreover, the encapsulated GSP in the emulsion showed a remarkably higher bioaccessibility (40.72%) compared to free GSP (13.11%) in the simulated gastrointestinal digestion. These results indicated that G-AWC-stabilized W/O/W emulsions could be an effective carrier to encapsulate water-soluble bioactive compounds with enhanced stability and bioaccessibility.


Assuntos
Reagentes de Ligações Cruzadas/química , Digestão , Manipulação de Alimentos , Extrato de Sementes de Uva/química , Iridoides/química , Óleos/química , Polissacarídeos/química , Proantocianidinas/química , Água/química , Proteínas do Soro do Leite/química , Disponibilidade Biológica , Emulsificantes/química , Emulsões , Suco Gástrico/química , Géis , Glicerol/análogos & derivados , Glicerol/química , Concentração de Íons de Hidrogênio , Secreções Intestinais/química , Lipólise , Ácidos Ricinoleicos/química , Solubilidade
17.
Molecules ; 26(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34072180

RESUMO

Herein, we prepared 1,3-dipalmitoyl-2-oleoyl glycerol (POP)-rich fats with reduced levels of diacylglycerols (DAGs), adversely affecting the tempering of chocolate, via two-step hexane fractionation of palm stearin. DAG content in the as-prepared fats was lower than that in POP-rich fats obtained by previously reported conventional two-step acetone fractionation. Cocoa butter equivalents (CBEs) were fabricated by blending the as-prepared fats with 1,3-distearoyl-2-oleoyl glycerol (SOS)-rich fats obtained by hexane fractionation of degummed shea butter. POP-rich fats achieved under the best conditions for the fractionation of palm stearin had a significantly lower DAG content (1.6 w/w%) than that in the counterpart (4.6 w/w%) prepared by the previously reported method. The CBEs fabricated by blending the POP- and SOS-rich fats in a weight ratio of 40:60 contained 63.7 w/w% total symmetric monounsaturated triacylglycerols, including 22.0 w/w% POP, 8.6 w/w% palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol, 33.1 w/w% SOS, and 1.3 w/w% DAGs, which was not substantially different from the DAG content in cocoa butter (1.1 w/w%). Based on the solid-fat content results, it was concluded that, when these CBEs were used for chocolate manufacture, they blended with cocoa butter at levels up to 40 w/w%, without distinctively altering the hardness and melting behavior of cocoa butter.


Assuntos
Gorduras na Dieta/metabolismo , Diglicerídeos/química , Hexanos/química , Óleo de Palmeira/química , Cacau/química , Varredura Diferencial de Calorimetria , Cromatografia Líquida de Alta Pressão , Ácidos Graxos/química , Glicerol/química , Óleos de Plantas/química , Temperatura , Triglicerídeos/química
18.
Cells ; 10(5)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064643

RESUMO

Twenty to thirty percent of the septating mycobacterial cells of the mid-log phase population showed highly deviated asymmetric constriction during division (ACD), while the remaining underwent symmetric constriction during division (SCD). The ACD produced short-sized cells (SCs) and normal/long-sized cells (NCs) as the sister-daughter cells, but with significant differential susceptibility to antibiotic/oxidative/nitrite stress. Here we report that, at 0.2% glycerol, formulated in the Middlebrook 7H9 medium, a significantly high proportion of the cells were divided by SCD. When the glycerol concentration decreased to 0.1% due to cell-growth/division, the ACD proportion gradually increased until the ACD:SCD ratio reached ~50:50. With further decrease in the glycerol levels, the SCD proportion increased with concomitant decrease in the ACD proportion. Maintenance of glycerol at 0.1%, through replenishment, held the ACD:SCD proportion at ~50:50. Transfer of the cells from one culture with a specific glycerol level to the supernatant from another culture, with a different glycerol level, made the cells change the ACD:SCD proportion to that of the culture from which the supernatant was taken. RT-qPCR data showed the possibility of diadenosine tetraphosphate phosphorylase (MSMEG_2932), phosphatidylinositol synthase (MSMEG_2933), and a Nudix family hydrolase (MSMEG_2936) involved in the ACD:SCD proportion-change in response to glycerol levels. We also discussed its physiological significance.


Assuntos
Glicerol/metabolismo , Mycobacterium bovis/metabolismo , Mycobacterium smegmatis/metabolismo , Mycobacterium tuberculosis/metabolismo , Hidrolases Anidrido Ácido/metabolismo , Antioxidantes/metabolismo , CDP-Diacilglicerol-Inositol 3-Fosfatidiltransferase/metabolismo , Proliferação de Células , Meios de Cultura , DNA Complementar/metabolismo , Glicerol/química , Humanos , Mutação , Estresse Oxidativo , Pirofosfatases/metabolismo , RNA/metabolismo , Tuberculose , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Nudix Hidrolases
19.
J Chromatogr A ; 1650: 462253, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34049252

RESUMO

The potentially carcinogenic process contaminant 3- and 2-monochloropropanediol esters (2-MCPD and 3-MCPD esters) and glycidyl esters (GEs) are under study in refined oils and foodstuffs. Legislation set recommended total daily intake (TDI) for 3-MCPD of 0.8 µg/kg and as low as reasonably achievable (ALARA) for glycidol. Usually, the so far adopted method for the determination of these contaminants relay on numerous and time-consuming steps for sample preparation (AOCS methods) and on GC-MS detection. The obtained sensitivities and the number of processable samples are thus limited. In this optic, new reliable methods that allow for the fast and sensitive determination of these contaminants in edible oils may be considered an improvement of the overall strategy of tackling the problem. In this paper a new automated method for sample preparation and detection by GC-MS/MS is presented and validated. Data on sensitivity (LOD at 1.5, 2.2 and 3 ng/g for 3-MCPD, 2-MCPD, 3-MBPD (deriving from glycidol), respectively), linearity across low and high calibration ranges and precision showed to be fit-for-purposes. Finally, the methodology was applied to ten extra virgin oil samples and one sample of sunflower seeds oil.


Assuntos
Ésteres , Análise de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Óleos de Plantas , Carcinógenos/análise , Compostos de Epóxi/química , Ésteres/análise , Ésteres/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Glicerol/análogos & derivados , Glicerol/química , Azeite de Oliva/química , Óleos de Plantas/química , Propanóis/química , Propilenoglicóis/química , Óleo de Girassol/química , Espectrometria de Massas em Tandem/métodos
20.
Int J Biol Macromol ; 181: 1003-1009, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33892026

RESUMO

Due to the convenience, fresh-cut vegetables or fruits as the emerging commercial products have attracted much attention in recent years. However, the preservation of food with high quality remains a big challenge. In this study, one novel kind of edible composite film (PAX) consisted of pectin, sodium alginate (SA), and xanthan gum (XG) was well developed. The optimum concentrations for pectin and SA in PAX film based on the shearing viscosity were 6 g/L and 5 g/L, respectively. Upon this condition, the experimental results from the response surface methodology showed that the tensile strength for the optimized PAX (PAXO) film can reach the maximum value of 29.65 MPa at the concentration of 4 g/L XG, 18 g/L glycerol, and 20 g/L CaCl2. The corresponding elongation at break was 19.02% and the water vapor transmission rate was evaluated to be 18.12 × 10-11 g/(m2·s·pa). Furthermore, the nanocomposites in terms of coating or films were used to keep fresh-cut potatoes, where they exhibited different efficiencies in food preservation with the order: PAXO coating + CaCl2 ≈ PAXO coating > PAXO film > sterile water. All the results indicated that the as-prepared PAXO film or PAXO solution could be good candidates in packaging preservation.


Assuntos
Filmes Comestíveis , Conservação de Alimentos , Nanocompostos/química , Pectinas/química , Alginatos/química , Embalagem de Alimentos , Frutas/efeitos dos fármacos , Glicerol/química , Polissacarídeos Bacterianos/química , Vapor , Água/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA