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1.
Nutrients ; 16(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38398890

RESUMO

The utilization of food as a therapeutic measure for various ailments has been a prevalent practice throughout history and across different cultures. This is exemplified in societies where substances like Hibiscus sabdariffa have been employed to manage health conditions like hypertension and elevated blood glucose levels. The inherent bioactive compounds found in this plant, namely, delphinidin-3-sambubioside (DS3), quercetin (QRC), and hibiscus acid (HA), have been linked to various health benefits. Despite receiving individual attention, the specific molecular targets for these compounds remain unclear. In this study, computational analysis was conducted using bioinformatics tools such as Swiss Target Prediction, ShinnyGo 0.77, KEGG, and Stringdb to identify the molecular targets, pathways, and hub genes. Supplementary results were obtained through a thorough literature search in PubMed. DS3 analysis revealed potential genetic alterations related to the metabolism of nitrogen and glucose, inflammation, angiogenesis, and cell proliferation, particularly impacting the PI3K-AKT signaling pathway. QRC analysis demonstrated interconnected targets spanning multiple pathways, with some overlap with DS3 analysis and a particular focus on pathways related to cancer. HA analysis revealed distinct targets, especially those associated with pathways related to the nervous system. These findings emphasize the necessity for focused research on the molecular effects of DS3, QRC, and HA, thereby providing valuable insights into potential therapeutic pathways.


Assuntos
Antocianinas , Citratos , Hibiscus , Quercetina , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/análise , Fosfatidilinositol 3-Quinases
2.
Biol Trace Elem Res ; 202(2): 558-568, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37119340

RESUMO

Fructose consumption has increased globally and has been linked to obesity, insulin resistance, and diabetes. Selenium nanoparticles (SeNPs) can regulate glucose and lipid concentrations and have immunoregulatory properties. Four study groups (n = 7/group) of eight-week-old male mice (Balb/c) were formed for this investigation. One group received a standard diet (C), another standard diet plus SeNPs (C + SeNPs), a high fructose diet (F), and a group with a high fructose diet plus SeNPs (F + SeNPs). Weight, glucose, triglycerides, and cholesterol were evaluated. In the end, mice were sacrificed, blood samples were obtained to assess cytokine profile, and liver, kidney, and pancreas were removed for histological examination. The study was complemented with an in silico analysis where the CTD, STITCH, ToppGene Suite, ShinyGO 0.76.3 databases, and Cytoscape software were implemented. The results of in vivo analysis showed that SeNPs regulated biochemical parameters and showed anti-inflammatory effects by decreasing the concentrations of TNF-alpha, IL-1beta, and IFN-gamma and increasing IL-10. No damage was observed in the studied organs. In addition, SeNPs regulate oxidative stress, preserve cell organelles, and regulate metabolic pathways to avoid the adverse effects of fructose consumption, according to bioinformatics analysis. In conclusion, SeNPs protect against the undesirable effects of a diet rich in fructose.


Assuntos
Nanopartículas , Selênio , Camundongos , Masculino , Animais , Selênio/farmacologia , Selênio/química , Cebolas , Frutose/farmacologia , Estresse Oxidativo , Nanopartículas/química , Dieta , Glucose
3.
Adv Colloid Interface Sci ; 318: 102938, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37329675

RESUMO

The health benefits provided by plant matrices is due to the presence of certain compounds that, in studies carried out in vitro and in vivo, have shown to have biological activity in certain conditions, not only as a natural treatment against various conditions, but also for the quality of preventing chronic diseases, these compounds, already identified and studied, they can increase their biological function by undergoing structural chemical modifications or by being incorporated into polymer matrices that allow, in the first instance, to protect said compound and increase its bioaccessibility, as well as to preserve or increase the biological effects. Although the stabilization of compounds is an important aspect, it is also the study of the kinetic parameters of the system that contains them, since, due to these studies, the potential application to these systems can be designated. In this review we will address some of the work focused on obtaining compounds with biological activity from plant sources, the functionalization of extracts through double emulsions and nanoemulsions, as well as their toxicity and finally the pharmacokinetic aspects of entrapment systems.


Assuntos
Extratos Vegetais , Extratos Vegetais/farmacologia , Emulsões/química , Disponibilidade Biológica
4.
Molecules ; 28(10)2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37241822

RESUMO

Phytochemicals are natural compounds found in plants that have potential health benefits such as antioxidants, anti-inflammatory and anti-cancer properties, and immune reinforcement. Polygonum cuspidatum Sieb. et Zucc. is a source rich in resveratrol, traditionally consumed as an infusion. In this study, P. cuspidatum root extraction conditions were optimized to increase antioxidant capacity (DPPH, ABTS+), extraction yield, resveratrol concentration, and total polyphenolic compounds (TPC) via ultrasonic-assisted extraction using a Box-Behnken design (BBD). The biological activities of the optimized extract and the infusion were compared. The optimized extract was obtained using a solvent/root powder ratio of 4, 60% ethanol concentration, and 60% ultrasonic power. The optimized extract showed higher biological activities than the infusion. The optimized extract contained 16.6 mg mL-1 resveratrol, high antioxidant activities (135.1 µg TE mL-1 for DPPH, and 230.4 µg TE mL-1 for ABTS+), TPC (33.2 mg GAE mL-1), and extraction yield of 12.4%. The EC50 value (effective concentration 50) of the optimized extract was 0.194 µg mL-1, which revealed high cytotoxic activity against the Caco-2 cell line. The optimized extract could be used to develop functional beverages with high antioxidant capacity, antioxidants for edible oils, functional foods, and cosmetics.


Assuntos
Fallopia japonica , Ultrassom , Humanos , Resveratrol/farmacologia , Antioxidantes/farmacologia , Fallopia japonica/química , Células CACO-2 , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Alimento Funcional
5.
Int J Pharm ; 640: 123017, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37149112

RESUMO

Mathematical models are used to characterize and optimize drug release in drug delivery systems (DDS). One of the most widely used DDS is the poly(lactic-co-glycolic acid) (PLGA)-based polymeric matrix owing to its biodegradability, biocompatibility, and easy manipulation of its properties through the manipulation of synthesis processes. Over the years, the Korsmeyer-Peppas model has been the most widely used model for characterizing the release profiles of PLGA DDS. However, owing to the limitations of the Korsmeyer-Peppas model, the Weibull model has emerged as an alternative for the characterization of the release profiles of PLGA polymeric matrices. The purpose of this study was to establish a correlation between the n and ß parameters of the Korsmeyer-Peppas and Weibull models and to use the Weibull model to discern the drug release mechanism. A total of 451 datasets describing the overtime drug release of PLGA-based formulations from 173 scientific articles were fitted to both models. The Korsmeyer-Peppas model had a mean Akaike Information Criteria (AIC) value of 54.52 and an n value of 0.42, while the Weibull model had a mean AIC of 51.99 and a ß value of 0.55, and by using reduced major axis regression values, a high correlation was found between the n and ß values. These results demonstrate the ability of the Weibull model to characterize the release profiles of PLGA-based matrices and the usefulness of the ß parameter for determining the drug release mechanism.


Assuntos
Ácido Láctico , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Liberação Controlada de Fármacos , Sistemas de Liberação de Medicamentos
6.
Materials (Basel) ; 15(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36234123

RESUMO

Nanostructured catalysts of platinum (Pt) supported on commercial TiO2, as well as TiO2-CeO2 (1, 5 and 10 wt% CeO2), were synthesized through the Sol-Gel and impregnation method doped to 1 wt% of Platinum, in order to obtain a viable photocatalytic material able to oxidate organic pollutants under the visible light spectrum. The materials were characterized by different spectroscopy and surface techniques such as Specific surface area (BET), X-ray photoelectron spectroscopy (XPS), XRD, and TEM. The results showed an increase in the diameter of the pore as well as the superficial area of the supports as a function of the CeO2 content. TEM images showed Pt nanoparticles ranking from 2-7 nm, a decrease in the particle size due to the increase of CeO2. The XPS showed oxidized Pt2+ and reduced Pt0 species; also, the relative abundance of the elements Ce3+/Ce4- and Ti4+ on the catalysts. Additionally, a shift in the Eg band gap energy (3.02-2.82 eV) was observed by UV-vis, proving the facticity of applying these materials in a photocatalytic reaction using visible light. Finally, all the synthesized materials were tested on their photocatalytic oxidation activity on a herbicide used worldwide; 2,4-Dichlorophenoxyacetic acid, frequently use in the agriculture in the state of Jalisco. The kinetics activity of each material was measured during 6 h of reaction at UV-Vis 190-400 nm, reaching a removal efficiency of 98% of the initial concentration of the pollutant in 6 h, compared to 32% using unmodified TiO2 in 6 h.

7.
Int J Mol Sci ; 23(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36142667

RESUMO

This paper reports the results of the PLGA-TiO2 nanocomposite regarding the green synthesis of titanium dioxide nanoparticles using a natural extract, its characterization, and encapsulation with poly(lactic-co-glycolic acid) (PLGA). UV-visible spectrometry was used for the identification of terpenes present in the extracts. The morphology of the nanoparticles was determined by scanning electron microscopy. Infrared spectroscopy was used for the determination of functional groups, while X-ray diffraction was used to determine the crystal structure. The analysis of the extended release of the encapsulated extract in the matrix of the nanomaterial resulted in a maximum visible UV absorbance at approximately 260 nm and confirmed the synthesis of titanium dioxide nanoparticles. Moreover, terpenes enhance synthesis and stabilize titanium dioxide nanoparticles. The synthesized structures are spherical and amorphous, 44 nm in size, and encapsulated at 65 nm.


Assuntos
Nanopartículas , Titânio , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Nanopartículas/química , Tamanho da Partícula , Extratos Vegetais/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Terpenos , Titânio/química
8.
Molecules ; 27(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36144779

RESUMO

The objective of this work was to find the optimal conditions by thermosonication-assisted extraction (TSAE) of the total acetogenin content (TAC) and yield from A. muricata seeds, assessing the effect of the temperature (40, 50, and 60 °C), sonication amplitude (80, 90, and 100%), and pulse-cycle (0.5, 0.7, and 1 s). In addition, optimal TSAE conditions of acetogenins (ACGs) were compared with extraction by ultrasound at 25 °C and the soxhlet method measuring TAC and antioxidant capacity. Moreover, solubility and identification of isolated ACGs were performed. Furthermore, the antifungal activity of ACGs crude extract and isolated ACGs was evaluated. Optimal TSAE conditions to extract the highest TAC (35.89 mg/g) and yield (3.6%) were 50 °C, 100% amplitude, and 0.5 s pulse-cycle. TSAE was 2.17-fold and 15.60-fold more effective than ultrasound at 25 °C and the Soxhlet method to extract ACGs with antioxidant capacity. Isolated ACGs were mostly soluble in acetone and methanol. Seven ACGs were identified, and pseudoannonacin was the most abundant. The inhibition of Candida albicans, Candida krusei, and Candida tropicalis was higher from isolated ACGs than crude extract. TSAE was effective to increase the yield in the ACGs extraction from A. muricata seeds and these ACGs have important antifungal activity.


Assuntos
Annona , Acetogeninas/farmacologia , Acetona , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Metanol , Extratos Vegetais/farmacologia , Sementes
9.
Curr Top Med Chem ; 22(30): 2506-2526, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36121083

RESUMO

Pathogenic microorganisms, including bacteria, are becoming resistant to most existing drugs, which increases the failure of pharmacologic treatment. Therefore, new nanomaterials were studied to spearhead improvement against the same resistant pathogenic bacteria. This has increased the mortality in the world population, principally in under-developed countries. Moreover, recently there has been research to find new drug formulations to kill the most dangerous microorganisms, such as bacteria cells which should avoid the spread of disease. Therefore, lately, investigations have been focusing on nanomaterials because they can exhibit the capacity to show an antibacterial effect. These studies have been trying oriented in their ability to produce an improvement to get antibacterial damage against the same pathogenic bacteria resistance. However, there are many problems with the use of nanoparticles. One of them is understanding how they act against bacteria, "their mechanism(s) action" to induce reduction or even kill the bacterial strains. Therefore, it is essential to understand the specific mechanism(s) of each nanomaterial used to observe the interaction between bacteria cells and nanoparticles. In addition, since nanoparticles can be functionalized with different antibacterial drugs, it is necessary to consider and distinguish the antibacterial activity of the nanoparticles from the antibacterial activity of the drugs to avoid confusion about how the nanoparticles work. Knowledge of these differences can help better understand the applications of the primary nanoparticles (i.e., Ag, Au, CuO, ZnO, and TiO2, among others) described in detail in this review which are toxic against various bacterial strains.


Assuntos
Infecções Bacterianas , Nanopartículas Metálicas , Nanopartículas , Humanos , Antibacterianos/farmacologia , Bactérias
10.
Int J Mol Sci ; 23(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35806263

RESUMO

This study aimed to develop Ca2+ doped ZnO nanoparticles (NPs) and investigate their antibacterial properties against microorganisms of dental interest. Zn-Ca NPs were synthesized by the sol-gel method with different concentrations of Ca2+ (1, 3, and 5 wt. %) and subsequently characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-vis spectroscopy and Fourier transform infrared spectroscopy (FT-IR). The Kirby-Bauer method was used to measure antibacterial effects. NPs showed the wurzite phase of ZnO and bandgap energies (Eg) from 2.99 to 3.04 eV. SEM analysis showed an average particle size of 80 to 160 nm. The treatments that presented the best antibacterial activity were Zn-Ca 3% and Zn-Ca 5%. ZnO NPs represent an alternative to generate and improve materials with antibacterial capacity for dental applications.


Assuntos
Nanopartículas Metálicas , Nanocompostos , Óxido de Zinco , Antibacterianos/química , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Nanocompostos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Zinco/farmacologia , Óxido de Zinco/química , Óxido de Zinco/farmacologia
11.
Nanomaterials (Basel) ; 12(12)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35745287

RESUMO

TiO2, ZnO, and their combination (TiO2−ZnO) at different molar ratios and pH values (Ti−Zn A and B 3:1, 1:1, and 1:3) via the sol−gel method were characterized by SEM, XRD, UV-Vis, and FT-IR. Moreover, antibacterial tests of the nanoparticles were conducted against Escherichia coli (E. coli), Salmonella paratyphi (S. paratyphi), Staphylococcus aureus (S. aureus), and Listeria monocytogenes (L. monocytogenes). The indirect bandgap of the Ti−Zn binary oxide synthesized in the basic process at molar ratios of 3:1, 1:1, and 1:3 exhibited a higher eV (3.31, 3.30, and 3.19 eV, respectively) compared to pure TiO2 (3.2 eV) and synthesized in the acid process (3.22, 3.29, and 3.19 eV at same molar ratio, respectively); in addition, the results of the indirect bandgap were interesting due to a difference found by other authors. Moreover, the sol−gel method promoted the formation of a spherical, semi-sphere, and semi-hexagonal shape (TiO2, Ti−Zn 1:1, and Ti−Zn 1:3) with a size ≤ 150 nm synthesized during the acid process, with a crystallite size of ~71, ~12, ~34, and ~21 nm, respectively, while ZnO NPs developed a hexagonal and large size (200−800 nm) under the same synthesis process (acid). Samples were classified as TiO2 anatase phase (basic synthesis); however, the presented changes developed in the rutile phase (24% rutile phase) at an acid pH during the synthesis process. Moreover, Ti−Zn maintained the anatase phase even with a molar ratio of 1:3. The most interesting assessment was the antibacterial test; the Ti−Zn A (1:3) demonstrated a bacteriostatic effect compared with all treatments except ZnO, which showed a similar effect in dark conditions, and only Gram-positive bacteria were susceptible (Listeria monocytogenes > Staphylococcus aureus). Therefore, the Ti−Zn characteristic suggests that the results have potential in treating wastewater as well as in pharmaceutical (as drug carriers) and medical applications.

12.
Anticancer Agents Med Chem ; 22(9): 1658-1673, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34515010

RESUMO

Health systems worldwide consider cancer a disease that causes the highest number of deaths per year. The low efficacy of current cancer therapies has led other areas of science to search for new alternatives, including nanomaterial sciences. Selenium nanoparticles have anticancer activity, as revealed by in vitro tests performed on prostate, breast, cervical, lung, colorectal, and liver cancer cell lines. Studies attribute anticancer activity to the anti-metastatic effect due to the inhibition of migration and invasion processes. The antiproliferative effect is the low expression of molecules such as cyclin D1, cyclin E, and CDK2. In addition to the activation of cell apoptosis by caspase-dependent mechanisms, there is a low expression of anti-apoptotic proteins such as Bcl-2 and a high expression of the apoptotic proteins like Bax and Bad. Other studies attribute anticancer activity to the activation of cell necroptosis, where molecules such as TNF and IRF1 participate. The pharmacological potential of selenium nanoparticles depends primarily on the administered dose, particle size, and chemical composition. Furthermore, several studies have shown that the administration of these nanoparticles is safe due to their low toxicity in non-cancerous cells. In this review, the most relevant antecedents on the anticancer potential of selenium nanoparticles in prostate, breast, cervical, lung, liver, and colorectal cancer cell lines are discussed.


Assuntos
Antineoplásicos , Nanopartículas , Selênio , Antineoplásicos/química , Apoptose , Linhagem Celular Tumoral , Humanos , Masculino , Nanopartículas/química , Selênio/química , Selênio/farmacologia
13.
Anticancer Agents Med Chem ; 22(12): 2241-2254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34963437

RESUMO

Recently, Titanium dioxide (TiO2) has been studied as an alternative to treat cancer diseases under different activation therapies. The aim of this review was to describe the effect of TiO2 nanoparticles (NPs) on some cancer cell lines and their interaction with phototherapies such as photodynamic therapy (PDT), photothermal therapy (PTT), sonodynamic therapy (SDT), and ultraviolet therapy (UV) for anticancer treatment. The use of TiO2 combined with PDT, PTT, SDT, or UV has shown a remarkable capacity to enhance the killing of cancer cells through reactive oxygen species formation. Thus, the combination of TiO2 and activation therapies exhibited great potential and could be a viable anticancer treatment strategy. However, more studies on phototherapies in combination with TiO2 and their effects under different experimental conditions (TiO2 concentration, type of cancer cells, and intensity and frequency of therapies) are necessary to guarantee the safe use of this kind of therapy.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Neoplasias/tratamento farmacológico , Fototerapia , Titânio/farmacologia
14.
J Nanosci Nanotechnol ; 21(11): 5383-5398, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33980348

RESUMO

Antimicrobial resistance has become a severe problem for health systems worldwide, and counteractions are challenging because of the lack of interest of pharmaceutical companies in generating new and effective antimicrobial drugs. Selenium nanoparticles have attracted considerable interest in treating bacteria, fungi, parasites, and viruses of clinical importance due to their high therapeutic efficacy and almost zero generation of adverse effects. Some studies have revealed that the antimicrobial activity of these nanoparticles is due to the generation of reactive oxygen species, but more studies are needed to clarify their antimicrobial mechanisms. Other studies show that their antimicrobial activity is increased when the surface of the nanoparticles is functionalized with some biomolecules or when their surface carries a specific drug. This review addresses the existing background on the antimicrobial potential offered by selenium nanoparticles against viruses, bacteria, fungi, and parasites of clinical importance.


Assuntos
Anti-Infecciosos , Nanopartículas , Preparações Farmacêuticas , Selênio , Anti-Infecciosos/farmacologia , Fungos
15.
Mini Rev Med Chem ; 21(14): 1798-1812, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33535949

RESUMO

Diabetes mellitus is a disease that presents great challenges for healthcare systems worldwide, and the identification of alternative therapies for the treatment of this disease is of vital importance. Metallic nanoparticles (gold, silver, and selenium) and metallic oxide (ZnO) have been studied in different areas such as medicine, biotechnology, the environment, and the food industry with promising results. In medicine, current research has revealed these nanoparticles' anti-diabetic properties thanks to the implementation of animal models. This review will address the existing antecedents and the effects of gold, silver, selenium, and zinc oxide nanoparticles in diabetes administered alone, functionalized with other molecules, or combined with drugs that have shown promising therapeutic effects. The anti-diabetic effects of these nanoparticles are related to the regulation of glucose, insulin, and lipid profiles. In addition, oxidative stress markers, liver and kidney markers, the reduction of inflammation, apoptosis of the pancreas, and the restoration of normal liver and kidney histology are also reported in the literature after using these nanoparticles. However, the therapeutic effects that these nanoparticles provide are limited due to the lack of specific protocols dictated by international organizations to evaluate the risks of using these nanoparticles.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Ouro/química , Hipoglicemiantes/uso terapêutico , Nanopartículas Metálicas/química , Selênio/química , Prata/química , Zinco/química , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Modelos Animais de Doenças , Hipoglicemiantes/química , Nanopartículas Metálicas/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo
16.
Molecules ; 25(5)2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32138341

RESUMO

The soursop fruit or Annona muricata (A. muricata) fruit is recognized by its bioactive compounds and acetogenins (ACG) are among the most important. The effect of ACGs, with greater importance in health, is that they present anti-tumor activity; however, the methods of extraction of ACGs are very slow and with a high expenditure of solvents. To our knowledge, there is no report of an optimal method for the extraction of acetogenins from the Annonaceae family by ultrasound-assisted extraction (UAE); therefore, the aim was to find the best UEA conditions of acetogenins from A. muricata fruit (peel, pulp, seed, and columella) by using response surface methodology. The effect of amplitude (40%, 70%, and 100%), time (5, 10, and 15 min), and pulse-cycle (0.4, 0.7, and 1 s) of ultrasound at 24 kHz was evaluated on the total acetogenin content (TAC). Optimal extraction conditions of acetogenins (ACGs) with UEA were compared with the extraction of ACGs by maceration. The optimal UEA conditions in the A. muricata pulp and by-products were dependent on each raw material. The highest TAC was found in the seed (13.01 mg/g dry weight (DW)), followed by the peel (1.69 mg/g DW), the pulp (1.67 mg/g DW), and columella (1.52 mg/g DW). The experimental TAC correlated well with the model (Adjusted R2 with values between 0.88 and 0.97). The highest effectiveness in ACG extraction was obtained in seeds and peels using UEA compared to extraction by maceration (993% and 650%, respectively). The results showed that A. muricata by-products are an important source of ACGs and that UAE could be a viable alternative, with high potential for large-scale extraction.


Assuntos
Acetogeninas/química , Annona/química , Frutas/química , Extratos Vegetais/química , Ondas Ultrassônicas
17.
Materials (Basel) ; 13(4)2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32053948

RESUMO

In recent years, a strong interest has emerged in hybrid composites and their potential uses, especially in chitosan-titanium dioxide (CS-TiO2) composites, which have interesting technological properties and applications. This review describes the reported advantages and limitations of the functionalization of chitosan by adding TiO2 nanoparticles. Their effects on structural, textural, thermal, optical, mechanical, and vapor barrier properties and their biodegradability are also discussed. Evidence shows that the incorporation of TiO2 onto the CS matrix improves all the above properties in a dose-dependent manner. Nonetheless, the CS-TiO2 composite exhibits great potential applications including antimicrobial activity against bacteria and fungi; UV-barrier properties when it is used for packaging and textile purposes; environmental applications for removal of heavy metal ions and degradation of diverse water pollutants; biomedical applications as a wound-healing material, drug delivery system, or by the development of biosensors. Furthermore, no cytotoxic effects of CS-TiO2 have been reported on different cell lines, which supports their use for food and biomedical applications. Moreover, CS-TiO2 has also been used as an anti-corrosive material. However, the development of suitable protocols for CS-TiO2 composite preparation is mandatory for industrial-scale implementation.

18.
Foods ; 9(2)2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31991688

RESUMO

Aqueous and ethanolic extracts of Hibiscus sabdariffa were spray-dried using maltodextrin (MD) and gum arabic (GA) as carrier agents. A Taguchi L8 experimental design with seven variables was implemented. Physicochemical properties in the encapsulates were evaluated by Ultraviolet-Visible (UV-Vis,) X-ray Diffraction (XRD), spectroscopy and gravimetric techniques. Treatments with aqueous extracts showed the highest concentration of total soluble polyphenols (TSP) 32.12-21.23 mg equivalent gallic acid (EAG)/g dry weight (DW), and antioxidant capacity (AOX) in the 2,2-azinobis-3-ethylbenzotiazoline-6-sulfonic acid (ABTS) assay. The best treatment for TSP and AOX was T4: 2.5% Hibiscus w/w, aqueous extract, decoction, extract-to-carrier ratio 1:1 (w/w), proportion to carriers (MD:GA) 80:20 (w/w), 10,000 rpm, 150 °C. The Taguchi L8 design is a tool that allows the use of multiple variables with a low number of treatments that indicate the drying conditions that give the best parameters, focusing mainly on TSP and AOX, also, it is a good alternative for the preservation and stability of the phenolic compoudns in Hibiscus.

19.
Cancers (Basel) ; 11(12)2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31817789

RESUMO

Mangiferin is an important xanthone compound presenting various biological activities. The objective of this study was to develop, characterize physicochemical properties, and evaluate the anti-topoisomerase activity of poly(lactic-co-glycolic acid) (PLGA) nanoparticles containing mangiferin. The nanoparticles were developed by the emulsion solvent evaporation method and the optimal formulation was obtained with a response surface methodology (RSM); this formulation showed a mean size of 176.7 ± 1.021 nm with a 0.153 polydispersibility index (PDI) value, and mangiferin encapsulation efficiency was about 55%. The optimal conditions (6000 rpm, 10 min, and 300 µg of mangiferin) obtained 77% and the highest entrapment efficiency (97%). The in vitro release profile demonstrated a gradual release of mangiferin from 15 to 180 min in acidic conditions (pH 1.5). The fingerprint showed a modification in the maximum absorption wavelength of both the polymer and the mangiferin. Results of anti-toposiomerase assay showed that the optimal formulation (MG4, 25 µg/mL) had antiproliferative activity. High concentrations (2500 µg/mL) of MG4 showed non-in vitro cytotoxic effect on BEAS 2B and HEPG2. Finally, this study showed an encapsulation process with in vitro gastric digestion resistance (1.5 h) and without interfering with the metabolism of healthy cells and their biological activity.

20.
Nanomaterials (Basel) ; 9(7)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295802

RESUMO

Mixed oxide nanoparticles (MONs, TiO2-ZnO-MgO) obtained by the sol-gel method were characterized by transmission electron microscopy, (TEM, HRTEM, and SAED) and thermogravimetric analysis (TGA/DTGA-DTA). Furthermore, the effect of MONs on microbial growth (growth profiling curve, lethal and sublethal effect) of Escherichia coli, Salmonella paratyphi, Staphylococcus aureus and Listeria monocytogenes, as well as the toxicity against Artemia salina by the lethal concentration test (LC50) were evaluated. MONs exhibited a near-spherical in shape, polycrystalline structure and mean sizes from 17 to 23 nm. The thermal analysis revealed that the anatase phase of MONs is completed around 480-500 °C. The normal growth of all bacteria tested is affected by the MONs presence compared with the control group. MONs also exhibited a reduction on the plate count from 0.58 to 2.10 log CFU/mL with a sublethal cell injury from 17 to 98%. No significant toxicity within 24 h was observed on A. salina. A bacteriostatic effect of MONs on bacteria was evidenced, which was strongly influenced by the type of bacteria, as well as no toxic effects (LC50 >1000 mg/L; TiO2-ZnO (5%)-MgO (5%)) on A. salina were detected. This study demonstrates the potential of MONs for industrial applications.

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