Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Antioxidants (Basel) ; 12(4)2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37107230

RESUMEN

Two Helichrysum italicum extracts, OPT-1 (rich in phenolic acids) and OPT-2 (rich in total phenols and flavonoids), were prepared using hydroxypropyl-ß-cyclodextrin (HP-ß-CD)-assisted extraction. The prepared extracts were rich in phenolic compounds, including flavonoids and phenolic acids. GC-MS analysis of the extracts identified neryl acetate, neo-intermedeol, ß-selinene, γ-curcumene, italidione I, and nerol as the main volatile components of the extracts, as well as plant sterols, γ-sitosterol, campesterol, and stigmasterol. The antioxidant (DPPH radical scavenging, reducing power, and a carotene linoleic acid assay) and cosmeceutical (anti-hyaluronidase, anti-tyrosinase, anti-lipoxygenase, ovalbumin anti-coagulation, and a UV-absorption assay) activity of the extracts in most of the assays was better than the activity of the applied positive controls. Especially low were the IC50 values of the extracts in the anti-hyaluronidase (14.31 ± 0.29 µL extract/mL and 19.82 ± 1.53 µL extract/mL for OPT-1 and OPT-2, respectively) and the anti-lipoxygenase (0.96 ± 0.11 µL extract/mL and 1.07 ± 0.01 µL extract/mL for OPT-1 and OPT-2, respectively) assays. The extracts were non-toxic to HaCaT cells in concentrations of up to 62.5 µL extract/mL assuring their status as excellent candidates for cosmeceutical product development appropriate for direct use in cosmetic products without solvent evaporation.

2.
Materials (Basel) ; 15(2)2022 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-35057186

RESUMEN

The purpose of the research was to measure the increase in the binding of inclusion complexes ß-cyclodextrin-peppermint oil (ß-CD_PM) to cellulose in cotton and cotton/polyester material with BTCA as the crosslinking agent by applying an ultrasonic bath at room temperature and a frequency of 80 kHz for 10 min. After sonication, the samples were left in a bath for 24 h after which they were dried, thermocondensed and subjected to a number of wash cycles. The treated samples were analysed with Attenuated total reflection (ATR) units heated up to 300 °C (Golden Gate (FTIR-ATR)) to monitor chemical changes indicative of crosslinking, while physico-chemical changes in the samples were monitored by using Fourier transform infrared spectroscopy (FTIR-ATR). Mechanical properties were measured according to EN ISO 13934-1:1999, and coloristic changes were evaluated by the whiteness degree according to CIE (WCIE) and the yellowing index (YI), while antimicrobial activity was determined according to AATCC TM 147-2016. The results show a physico-chemical modification of the UZV-treated cellulosic material. Moreover, partial antimicrobial efficacy on Gram-negative bacteria was confirmed for treated fabrics.

3.
Molecules ; 25(21)2020 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-33167320

RESUMEN

Echinacea purpurea is used in herbal medicinal products for the prevention and treatment of the common cold, as well as for skin disorders and minor wounds. In this study, the efficiency of traditional maceration using water and ethanol was compared with the maceration using mixtures of water and glycerol, a non-toxic, biodegradable solvent from renewable sources. It was found that the glycerol-water mixtures were as effective as ethanol/water mixtures for the extraction of caffeic acid derivatives. All the prepared extracts demonstrated notable antiradical properties. Furthermore, an efficient ultrasound-assisted extraction using glycerol-water mixtures was developed using six independent variables. Their levels needed for the maximum extraction of caffeic acid derivatives were as follows: glycerol 90% (m/m), temperature 70 °C, ultrasound power 72 W, time 40 min, and ascorbic acid 0 mg/mL. Under the optimized conditions, ultrasound-assisted extraction was superior to maceration. It achieved significantly higher yields of phenolic acids in shorter extraction time. The presence of zinc in plant material may contribute to the beneficial effects of E. purpurea preparations. Since glycerol is a non-toxic solvent with humectant properties, the prepared extracts can be directly used for the preparation of cosmetics or oral pharmaceutical formulations without the need for solvent removal.


Asunto(s)
Antioxidantes/química , Echinacea/química , Hidroxibenzoatos/química , Ácidos Cafeicos/química , Cromatografía Líquida de Alta Presión , Etanol/química , Depuradores de Radicales Libres/química , Radicales Libres , Glicerol/química , Fenoles/química , Fitoterapia , Componentes Aéreos de las Plantas/química , Extractos Vegetales , Proteínas de Plantas/metabolismo , Plantas Medicinales/química , Polvos , Solventes , Succinatos/química , Ultrasonido , Viscosidad , Agua/química , Zinc/química
4.
Anal Methods ; 12(40): 4899-4905, 2020 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-32974630

RESUMEN

Trace elements are essential for the normal spermatogenesis of mammals and play a critical role in sperm quality and pathological processes e.g. inflammation. Consequently, multi-elemental analysis of seminal plasma (SP) may provide significant information on physiological and pathophysiological processes occurring in the male reproductive tract. Therefore, the development of a simple, fast and reliable method for seminal plasma (SP) analysis by total reflection X-ray fluorescence spectrometry (TXRF) could be useful for both, scientific and clinical studies. In this study, a detailed assessment of the sample preparation parameters and measurement conditions, including analysis of the shape and element distribution of the deposited residue on the reflector by micro X-ray fluorescence spectrometry, was carried out. Using the best analytical conditions, limits of detection for trace elements were found to be in the range of 0.04-0.3 mg kg-1. Trueness and precision of the results, evaluated by spiked SP sample analysis, were in most cases acceptable with recovery values in the range of 87-109% and relative standard deviations 3-12% (n = 5). The developed TXRF method was applied for the analysis of several SP samples from patients with different diagnoses and the results were compared with those obtained by ICP-OES. Among the studied trace elements with a role in the antioxidant defence system only Zn could be quantified and some differences in Zn concentrations among studied groups were observed. However, further studies on a large number of samples are required to define the exact relationship between the element composition and semen quality.


Asunto(s)
Semen , Oligoelementos , Animales , Humanos , Masculino , Semen/química , Análisis de Semen , Espectrometría por Rayos X , Oligoelementos/análisis , Zinc
5.
Anal Bioanal Chem ; 411(8): 1659-1670, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30707263

RESUMEN

Multielemental analysis of whole blood can provide significant information for the evaluation of nutritional status and diagnosis of certain diseases as well as for the assessment of exposure to potentially toxic metals. However, the quantification of multiple elements in whole blood is not easy partly because of the wide variation in element concentrations (from ng L-1 to g L-1) and the complex matrix. The aim of this work was to develop a fast, sustainable, and reliable analytical method, in combination with low-power TXRF, for multielemental analysis of blood samples. Firstly, a set of experiments were carried out to select the best diluent type and dilution factor using the control material SeronormTM Trace Elements Whole Blood L-1. A critical evaluation of the parameters affecting the sample deposition on the reflector was also carried out including a study of the shape and element distribution of the deposited residue on the reflector by micro X-ray fluorescence spectrometry. Using the best analytical conditions, limits of detection estimated were in the low milligrams per kilogram range and similar to those obtained using more complex sample treatments such as digestion. Accuracy and precision of the results were in most cases acceptable (recoveries 89-102%, RSD 6-8%, n = 5). Only underestimated values were obtained for light elements such as potassium. To prove the applicability of the method, several blood samples from control and thyroid disease patients were analyzed. Despite the fact that more samples need to be analyzed, it seems that Zn and Br contents in some of the patients are significantly higher compared to control samples. Graphical abstract.


Asunto(s)
Análisis Químico de la Sangre/métodos , Espectrometría por Rayos X/métodos , Enfermedades de la Tiroides/sangre , Adulto , Anciano , Elementos Químicos , Humanos , Persona de Mediana Edad , Enfermedades de la Tiroides/diagnóstico , Glándula Tiroides/patología
6.
J Microencapsul ; 35(1): 1-12, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29168930

RESUMEN

This work aimed to investigate the potential effect of cyclodextrin encapsulation on intrinsic ability of daidzein (DAD) and genistein (GEN) to inhibit the glycosaminoglycan (GAG) synthesis in fibroblasts originating from patients with mucopolysaccharidosis (MPS), type II and III. DAD or GEN encapsulation with either 2-hydroxypropyl-ß-cyclodextrin or sulphobuthylether-ß-cyclodextrin were achieved by neat grinding and were characterised by thermal analysis, X-ray powder diffraction, scanning electron microscopy and solubility testing which confirmed the complexes formation with increased solubility with respect to starting compounds. Both isoflavones, as well as their co-ground cyclodextrin complexes reduced GAG levels in the fibroblasts of MPS II and MPS III patients from 54.8-77.5%, in a dose dependent manner, without any significant cytotoxic effect. Cyclodextrin encapsulation did not change the intrinsically high effect of both DAD and GEN on the GAG level reduction in the treated cells, thus could be considered as a part of combination therapies of MPS.


Asunto(s)
Ciclodextrinas , Fibroblastos/metabolismo , Genisteína , Glicosaminoglicanos/metabolismo , Isoflavonas , Mucopolisacaridosis II , Mucopolisacaridosis I , Células Cultivadas , Ciclodextrinas/química , Ciclodextrinas/farmacología , Femenino , Genisteína/química , Genisteína/farmacología , Humanos , Isoflavonas/química , Isoflavonas/farmacología , Masculino , Mucopolisacaridosis I/tratamiento farmacológico , Mucopolisacaridosis I/metabolismo , Mucopolisacaridosis II/tratamiento farmacológico , Mucopolisacaridosis II/metabolismo
7.
Molecules ; 22(5)2017 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-28452948

RESUMEN

Vaccinium myrtillus (bilberry) leaf is traditionally used in southeastern Europe for the treatment of diabetes. In the present study, the ability of bilberry leaf extracts to inhibit carbohydrate-hydrolyzing enzymes and restore glutathione concentration in Hep G2 cells subjected to glucose-induced oxidative stress was investigated. A comprehensive analysis of the antioxidant activity of two bilberry leaf extracts was performed. The aqueous extract showed excellent total antioxidant and chelating activity. Its antioxidant activity in the ß-carotene-linoleic acid assay was very good, reaching the activity of the antioxidant standard BHA (93.4 ± 2.3% vs. 95.1 ± 2.4%, respectively). The hydroethanolic extract (ethanol/H2O, 8:2, v/v), on the other hand, was a better radical scavenger and Fe2+ reducing agent. Furthermore, the aqueous extract was able to efficiently increase glutathione concentration in Hep G2 cells subjected to glucose-induced oxidative stress and restore it to the levels observed in non-hyperglycaemic cells. The hydroethanolic extract strongly inhibited α-glucosidase, with the IC50 statistically equal to the antidiabetic drug acarbose (0.29 ± 0.02 mg/mL vs. 0.50 ± 0.01 mg/mL, respectively). Phytochemical analysis revealed the presence of quercetin and kaemferol derivatives, as well as chlorogenic and p-coumaric acid. The study results indicate that V. myrtillus leaf may have promising properties as a supporting therapy for diabetes.


Asunto(s)
Depuradores de Radicales Libres/química , Inhibidores de Glicósido Hidrolasas/química , Extractos Vegetales/química , Hojas de la Planta/química , Vaccinium myrtillus/química , Benzotiazoles/química , Compuestos de Bifenilo/química , Etanol/química , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Radicales Libres/química , Glutatión/metabolismo , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Inhibidores de Glicósido Hidrolasas/farmacología , Células Hep G2 , Humanos , Oxidación-Reducción , Estrés Oxidativo , Picratos/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Solventes/química , Ácidos Sulfónicos/química , Agua/química
8.
J Trace Elem Med Biol ; 41: 54-59, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28347463

RESUMEN

The aim of the present study was to explore impact of endurance exercise on urinary level of minerals and trace elements as well as on some oxidative stress and biochemical parameters. Urine samples were collected from participants (n=21) of mountain ultra-marathon race (53km; Medvednica, Zagreb, Croatia), before (baseline value), immediately after, 12h and 24h after the race. In urine samples level of minerals (Ca, P, K and Na) and trace elements (Se, Zn, Mn, Cu, Fe and Co) were assessed using the bench top Total reflection X-ray Fluorescence (TXRF) spectrometer. Oxidative stress was determined as level of malondialdehyde (MDA). Immediately after the race level of minerals, trace elements, MDA, creatinine, ketones, erythrocytes and specific gravity increased compared to their baseline value. In 24h follow-up trace elements involved in antioxidant defence, MDA and biochemical parameters returned to their baseline values, Cu and Co remained increased as after the race, Fe and K tended to return to baseline values while Ca, P and Na continued to increase. Mountain ultra-marathon resulted in alteration of physiologically important minerals and trace elements that for some minerals and trace elements persist, indicating their involvement in recovery processes. However, due to their loss in urine, level of minerals and trace elements in athletes participating in endurance exercise should be monitored.


Asunto(s)
Atletas , Minerales/orina , Carrera , Oligoelementos/orina , Adulto , Femenino , Humanos , Masculino
9.
J Pharm Biomed Anal ; 137: 42-53, 2017 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-28092854

RESUMEN

Mechanochemical activation using several different co-grinding additives was applied as a green chemistry approach to improve physiochemical and biopharmaceutical properties of praziquantel (PZQ). Liquid assisted grinding with an equimolar amount of citric acid (CA), malic acid (MA), salicylic acid (SA) and tartaric acid (TA) gained in cocrystal formation, which all showed pH-dependent solubility and dissolution rate. However, the most soluble cocrystal of PZQ with MA was chemically unstable, as seen during the stability testing. Equimolar cyclodextrin complexes prepared by neat grinding with amorphous hydroxypropyl-ß-cyclodextrin (HPßCD) and randomly methylated ß-cyclodextrin (MEßCD) showed the highest improvement in drug solubility and the dissolution rate, but only PZQ/HPßCD product presented an acceptable chemical and photostability profile. A combined approach, by co-grinding the drug with both MA and HPßCD in equimolar ratio, also gave highly soluble amorphous product which again was chemical instable and therefore not suitable for the pharmaceutical use. Studies on Caco-2 monolayer confirmed the biocompatibility of PZQ/HPßCD complex and showed that complexation did not adversely affect the intrinsically high PZQ permeability (Papp(PZQ)=(3.72±0.33)×10-5cms-1 and Papp(PZQ/HPßCD)=(3.65±0.21)×10-5cms-1; p>0.05). All this confirmed that the co-grinding with the proper additive is as a promising strategy to improve biopharmaceutical properties of the drug.


Asunto(s)
Ciclodextrinas/química , Praziquantel/química , Materiales Biocompatibles/química , Células CACO-2 , Línea Celular Tumoral , Química Farmacéutica/métodos , Humanos , Solubilidad , Tecnología Farmacéutica/métodos , beta-Ciclodextrinas/química
10.
Acta Pharm ; 65(2): 207-13, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26011937

RESUMEN

Thermal properties of N-carbamoyl benzotriazole derivatives and N,N',N''-tribenzyloxyisocyanuric acid were investigated using thermogravimetric analysis and differential scanning calorimetry. The results revealed a difference between structural analogs of N-carbamoyl benzotriazole derivatives. They seem to be in agreement with the previously proposed formation of N,N',N''-tribenzyloxyisocyanuric acid from 1-(N-benzyloxycarbamoyl) benzotriazole, via an intermediary N-benzyloxyisocyanate acid, during heating. Substantially different thermal properties were observed for structural analogues, 1-(N-methoxycarbamoyl) benzotriazole and 1-(N-ethoxycarbamoyl) benzotriazole. In contrast to N-benzyloxyisocyanate, no corresponding reactions were observed for their decomposition products, i.e., methoxyisocyanate and ethoxyisocyanate.


Asunto(s)
Rastreo Diferencial de Calorimetría/métodos , Isocianatos/química , Termogravimetría/métodos , Triazoles/química , Calor
11.
J Pharm Biomed Anal ; 71: 35-44, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22898722

RESUMEN

The aim of this work was to investigate the potential synergistic effect of water-soluble polymers (hypromellose, HPMC and polyvinylpyrrolidone, PVP) on zaleplon (ZAL) complexation with parent ß-cyclodextrin (ßCD) and its randomly methylated derivative (RAMEB) in solution and in solid state. The addition of HPMC to the complexation medium improved ZAL complexation and solubilization with RAMEB (K(ZAL/RAMEB)=156±5M(-1) and K(ZAL/RAMEB/HPMC)=189±8M(-1); p<0.01), while such effect was not observed for ßCD (K(ZAL/ßCD)=112±2M(-1) and K(ZAL/ßCD/HPMC)=119±8M(-1); p>0.05). Although PVP increased the ZAL aqueous solubility from 0.22 to 0.27mg/mL, it did not show any synergistic effects on ZAL solubilization with the cyclodextrins tested. Binary and ternary systems of ZAL with ßCD, RAMEB and HPMC were prepared by spray-drying. Differential scanning calorimetry, X-ray powder diffraction and scanning electron microscopy demonstrated a partial ZAL amorphization in spray-dried binary and ternary systems with ßCD, while the drug was completely amorphous in all samples with RAMEB. Furthermore, inclusion complex formation in all systems prepared was confirmed by solid-state NMR spectroscopy. The in vitro dissolution rate followed the rank order ZAL/RAMEB/HPMC>ZAL/RAMEB=ZAL/ßCD/HPMC>ZAL/ßCD≫ZAL, clearly demonstrating the superior performance of RAMEB on ZAL complexation in the solid state and its synergistic effect with HPMC on drug solubility. Surprisingly, when loaded into tablets made with insoluble microcrystalline cellulose, RAMEB complexes had no positive effect on drug dissolution, because HPMC and RAMEB acted as a binders inside the tablets, prolonging their disintegration. Oppositely, the formulation with mannitol, a soluble excipient, containing a ternary RAMEB system, released the complete drug-dose in only 5min, clearly demonstrating its suitability for the development of immediate-release oral formulation of ZAL.


Asunto(s)
Acetamidas/análisis , Metilcelulosa/análogos & derivados , Povidona/análisis , Pirimidinas/análisis , beta-Ciclodextrinas/análisis , Acetamidas/química , Rastreo Diferencial de Calorimetría/métodos , Celulosa/química , Química Farmacéutica/métodos , Excipientes/análisis , Excipientes/química , Interacciones Hidrofóbicas e Hidrofílicas , Derivados de la Hipromelosa , Espectroscopía de Resonancia Magnética/métodos , Metilcelulosa/análisis , Metilcelulosa/química , Microscopía Electrónica de Rastreo/métodos , Soluciones Farmacéuticas/química , Povidona/química , Pirimidinas/química , Solubilidad , Comprimidos/química , Agua/química , Difracción de Rayos X/métodos , beta-Ciclodextrinas/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA