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1.
J Pharm Sci ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38972546

RESUMO

The quantification of both polymer and drug during the dissolution of an amorphous solid dispersion (ASD) in aqueous media arouses great interest and may aid in the formulation. However, the available quantification methods for polymer excipients are limited, expensive, and challenging compared to drugs. In this work, a size exclusion chromatography method (HPLC-SEC) was developed and validated to determine the concentration of a frequently used polymer excipient, Soluplus® (Sol). In order to develop a method for the quantification of dissolved Soluplus®, two methods (SEC-UV and SEC-RID) with two injection volumes were tested with standard solutions of three different batches of Soluplus. The developed HPLC-SEC-UV method showed acceptable linearity (R2 > 0.9990) for all batches of Soluplus, good accuracies above a concentration of 0.1 mg/mL (coefficient of variation < 2%), relatively good precision at a concentration of 0.1 mg/mL (coefficient of variation < 2.5%), and high recoveries at a concentration of 0.75 mg/mL (coefficient of variation < 0.5%). The presence of Felodipine (Fel) and Lumefantrine (Lum) in the liquid media did not interfere with Soluplus quantification. The use of various surfactants, such as Tween® 80, Tween® 20, Span® 80, Span® 20, Kolliphor® TPGS, and sodium lauryl sulphate at a low concentration (0.005 mg/mL) did not show any effect on Soluplus® and did not interfere with Soluplus® quantification with any of the Soluplus batches. The addition of lithium bromide (LiBr) to the mobile phase within a concentration range of 0.05 to 1.0 M did not improve Soluplus® quantification.

2.
Plants (Basel) ; 13(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38611548

RESUMO

Several preclinical studies suggest the potential of edible plants in controlling blood sugar levels and stabilizing diet. The goals of the study were to examine, analyze, and describe whether there are chemical compounds in dandelion and burdock roots that could have antidiabetic properties. The 70% ethyl alcohol and lyophilizate extracts (AE and LE, respectively), were used, and analyses were carried out on their total polysaccharide (TP), total phenolic content (TPC), tannin, and inulin. The antioxidant activity of extracts was determined using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay, and hypoglycemic properties were based on α-amylase activity. Liquid chromatography-mass spectrometry was used for the tentative identification of the chemical components. Qualitative techniques confirmed the presence of inulin in both roots. Analysis of TPC, tannin content, DPPH assay, and α-amylase activity revealed higher values for burdock compared to dandelion. However, dandelion exhibited higher TP content. Burdock contained a small amount of tannin, whereas the tannin content in dandelion was insignificant. All LE consistently exhibited higher values in all analyses and assays for all roots compared to AE. Despite burdock root showing overall better results, it is uncertain whether these plants can be recommended as antidiabetic agents without in vivo studies.

3.
Pharmaceutics ; 16(3)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38543256

RESUMO

Using microcrystalline cellulose (MCC) with plastic behaviour and calcium phosphate anhydrous (CaHPO4) with brittle behaviour under compaction is very popular in the pharmaceutical industry for achieving desirable structural-mechanical properties of tablet formulations. Thus, mixtures of specific grades of MCC and CaHPO4 were tested in volume proportions of 100-0, 75-25, 50-50, 25-75, and 0-100 at a constant weight-by-weight concentration of sodium stearyl fumarate lubricant, utilizing a state-of-the-art benchtop compaction simulator (STYL'One Nano). Tablet formulations were prepared at 100, 150, 250, 350, 450, and 500 MPa, and characterized by tabletability profile, ejection force profile, proportion-tensile strength relationship, proportion-porosity relationship, pressure-displacement, and elastic recovery profiles, as well as by in-/out-of-die Heckel plots and yield pressures. Interestingly, the 25-75 formulation demonstrated a two-stage out-of-die Heckel plot and was additionally investigated with X-ray micro-computed tomography (µCT). By post-processing the µCT data, the degree of brittle CaHPO4 particles falling apart, along with the increasing compression pressure, was quantified by means of the surface area to volume (S/V) ratio. For the 25-75 formulation, the first stage (up to 150 MPa) and second stage (above the 150 MPa) of the out-of-die Heckel plot could be attributed to predominant MCC and CaHPO4 deformation, respectively.

4.
Pharmaceuticals (Basel) ; 16(10)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37895878

RESUMO

Flavonoids are hydroxylated polyphenols that are widely distributed in plants with diverse health benefits. Despite their popularity, the bioavailability of flavonoids is often overlooked, impacting their efficacy and the comparison of products. The study discusses the bioavailability-related physicochemical properties of flavonoids, with a focus on the poorly soluble compounds commonly found in dietary supplements and herbal products. This review sums up the values of pKa, log P, solubility, permeability, and melting temperature of flavonoids. Experimental and calculated data were compiled for various flavonoid subclasses, revealing variations in their physicochemical properties. The investigation highlights the challenges posed by poorly soluble flavonoids and underscores the need for enabling formulation approaches to enhance their bioavailability and therapeutic potential. Compared to aglycones, flavonoid glycosides (with sugar moieties) tend to be more hydrophilic. Most of the reviewed aglycones and glycosides exhibit relatively low log P and high melting points, making them "brick dust" candidates. To improve solubility and absorption, strategies like size reduction, the potential use of solid dispersions and carriers, as well as lipid-based formulations have been discussed.

5.
Plants (Basel) ; 12(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37653885

RESUMO

The Tanacetum vulgare L. (Tansy) has several ethnobotanical uses, mostly related to the essential oil and sesquiterpene lactones, whereas information regarding other compounds is scarce. This research is designed to characterize the phenolic compounds (flavonoids, phenolic acids, and tannins) to analyze the thujone (which is toxic in high concentrations) content and to detect the antioxidant activity (DPPH assay) of extracts. The main highlights of our work provide a chemical profile of phenolic compounds of T. vulgare harvested from different regions of Latvia, as well as simultaneously support the ethnomedicinal uses for wild T. vulgare through the integration of phenolic compounds as one of the value constituents of leaves and flowers. The extraction yield was 18 to 20% for leaves and 8 to 16% for flowers. The total phenol content in the extracts of T. vulgare as well as their antioxidant activity was different between collection regions and the aerial parts ranging from 134 to 218 mg GAE/g and 32 to 182 mg L-1, respectively. A remarkable variation in the thujone (α + ß) content (0.4% up to 6%) was detected in the extracts. T. vulgare leaf extracts were rich in tannins (up to 19%). According to the parameters detected, the extracts of T. vulgare could be considered promising for the development of new herbal products.

6.
Metabolites ; 13(8)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37623866

RESUMO

The twigs of sea buckthorn, blackcurrant, gooseberries, quince, and grapes were evaluated as a promising source of biologically active compounds-proanthocyanidins (PACs). Sea buckthorn twigs had the highest content of PACs (9.2% on dry biomass). Preliminary pretreatment of biomass with freon R134a did not allow an increase in PACs content in the composition of hydrophilic extract but confirmed the value of freon extract as an antibacterial agent against P. aeruginosa and B. cereus. The content of PACs was used as an indicator for assessment of the influence of hydrophilic extracts on pancreatic lipase activity. Under normal physiological conditions, in the presence of bile, the extract, which contained 42.4% of PACs was more effective compared to the extract which contained 17.5% of PACs. At all concentrations (0.2-40 mg of sample/g of pancreatic lipase), it inhibited lipase activity by 33%. Purified PACs were the most effective in inhibiting lipase activity (by 36%). However, in pathological physiological conditions (without bile), the opposite effect on lipase activity was observed. Thus, PACs and extracts can be used as inhibitors of pancreatic lipase only under normal physiological conditions.

7.
Molecules ; 28(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36677921

RESUMO

It has now been proven that many pathogens that cause infections and inflammation gradually mutate and become resistant to antibiotics. Chemically synthesized drugs treating inflammation most often only affect symptoms, but side effects could lead to the failure of human organs' functionality. On the other hand, plant-derived natural compounds have a long-term healing effect. It was shown that sea buckthorn (SBT) twigs are a rich source of biologically active compounds, including oligomeric proanthocyanidins (PACs). This study aimed to assess the anti-pathogenic and anti-inflammatory activity of water/ethanol extracts and PACs obtained from the lignocellulosic biomass of eight SBT cultivars. The anti-pathogenic activity of extracts and PACs was studied against pathogenic bacteria Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Bacillus cereus and fungus Candida albicans in 96-well plates by the two-fold serial broth microdilution method. The anti-bacterial activity of purified PACs was 4 and 10 times higher than for water and water/ethanol extracts, respectively, but the extracts had higher anti-fungal activity. Purified PACs showed the ability to reduce IL-8 and IL-6 secretion from poly-I:C-stimulated peripheral blood mononuclear cells. For the extracts and PACs of SBT cultivar 'Maria Bruvele' in the concentration range 0.0313-4.0 mg/mL, no toxic effect was observed.


Assuntos
Proantocianidinas , Humanos , Proantocianidinas/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Leucócitos Mononucleares , Bactérias , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antioxidantes/farmacologia , Etanol/farmacologia , Água/farmacologia , Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Testes de Sensibilidade Microbiana
8.
Plants (Basel) ; 11(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35736694

RESUMO

The barks of aspen (Populus tremula) and pine (Pinus sylvestris) are byproducts of wood processing, characterized by their low economic value. In the present study, microwave-assisted one-cycle water extraction was explored as a tool for the valorization of this biomass as a source of biologically active compounds. The microwave extractor of the original construction equipped with a pressurized extraction chamber and a condenser section was used. The microwave-assisted extraction (MAE), specially including dynamic dielectric heating up to 70 °C followed by 30 min of isothermal heating, promoted the isolation of salicin from aspen bark, allowing for the obtention of a two-times-higher free salicin concentration in water extracts (-14% vs. 7%) reached by multi-cycle accelerated solvent extraction (ASE), which is an advanced technique used as a reference. The MAE of pine bark with dynamic heating up to 90-130 °C, avoiding the isothermal heating step, allowed for the obtention of a 1.7-times-higher concentration of proantocyanidin dimers-tetramers, a 1.3-times-higher concentration of catechin and a 1.2-times-higher concentration of quinic acid in water extracts in comparison to a more time- and solvent-consuming ASE performed at the same temperature. The biological activity of the obtained extracts was characterized in terms of their ability to inhibit xahntine oxidase enzyme, which is a validated target for the therapeutic treatment of hyperuricemia.

9.
Plants (Basel) ; 11(5)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35270111

RESUMO

For sustainable sea buckthorn (Hippophae rhamnoides) berry production, the task at hand is to find an application for the large amount of biomass waste arising at harvesting. Sea buckthorn (SBT) vegetation is currently poorly studied. The purpose of this research was to assess the composition and potential of SBT twigs as a source of valuable biologically active substances. Water and 50% EtOH extracts of twigs of three Latvian SBT cultivars with a high berry yield and quality, popular for cultivation in many countries (H. rhamnoides 'Maria Bruvele', 'Tatiana', 'Botanicheskaya Lubitelskaya'), were investigated for the first time. The phytochemical composition (UHPLC-ESI-MS/MS analysis) and biological activity of the obtained hydrophilic extracts were determined. The highest yield of polyphenolic compounds and serotonin was observed for 'Maria Bruvele'. Hydrophilic extracts were investigated for radical scavenging activity (DPPH˙ test), antibacterial/antifungal activity against five pathogenic bacteria/yeast, cytotoxicity, and the enzymatic activity of alpha-amylase (via in vitro testing), which is extremely important for the treatment of people with underweight, wasting, and malabsorption. The results showed a high potential of sea buckthorn biomass as a source of valuable biologically active compounds for the creation of preparations for the food industry, nutraceuticals, and cosmetics.

10.
J Pharm Biomed Anal ; 214: 114727, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35306436

RESUMO

An experimentally proven novel analytical approach for chromatographic analysis of diarylheptanoids in grey alder (Alnus incana) and black alder (Alnus glutinosa) bark matrices was established. A method for qualitative and quantitative determination of oregonin (dominant diarylheptanoid) and semiquantitative analysis of related diarylheptanoids from alder bark using a photodiode array (PDA) detector coupled to a high-resolution mass spectrometer (QTOF-MS) was developed. A comparison of different liquid chromatography detectors (UV, MS and ELS) showed that only a combination of them is applicable for comprehensive analysis of multicomponent extracts. A total of sixteen different diarylheptanoids were simultaneously identified and semi-quantified in alder bark extracts. This is the first report of the method for individual and total diarylheptanoid determination in alder bark extracts, discussed in detail. The liquid chromatography complex is suggested as a tool for the reliable identification and quality control of the diarylheptanoids containing extracts isolated from the Alnus species and their dominant component - oregonin. The semiquantitative methodology established, and the dominant compound quantification provided means for assessing comparative sample complexities.


Assuntos
Alnus , Ilex , Alnus/química , Diarileptanoides/química , Casca de Planta/química , Extratos Vegetais/análise
11.
Res Vet Sci ; 131: 153-158, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32387554

RESUMO

The maintenance of high vitality and motility of ram's spermatozoa during storage at low temperatures has a crucial role for successful fertilization. This study evaluates the effect of the natural antioxidant oregonin on ram semen quality, stored at 5 °C for 48 h. Еighteen ejaculates (three repetitions for 6 ejaculates) from three local breed rams, collecting by artificial vagina, with volume > 1 ml, concentration > 1 × 109/ml and mass motility >3.5 were used for chilling. Each ejaculate was separated in two equal parts, diluted with Tris-glucose-glycerol-egg yolk extender with no oregonin or supplemented with 100µÐœ oregonin until adjustment of the sperm concentration to 200 × 106 cells/ml and stored at 5 °C for 48 h. The semen quality assessment was based on the main kinematic (by CASA analysis), morphological parameters (by BrightVit kit staining) and mitochondrial status (by MitoView staining) of the spermatozoa on 0, 24 and 48 h of storage, and on in vivo fertility test. Oregonin did not impair the morphology and kept sustained motility of ram spermatozoa stored at 5 °C for 48 h. The curvilinear velocity indicated faster movement of the oregonin treated sperms that corresponded with high percent of spermatozoa with active mitochondria in these samples. The fertilizing capacity of spermatozoa was preserved and pregnancy rate in the experimental group was 80% versus 60% in control. In conclusion, this study provides a new data about positive effect of the natural antioxidant oregonin, supplemented to the extender, on chilled ram semen quality, including fertilizing ability.


Assuntos
Alnus/química , Antioxidantes/farmacologia , Diarileptanoides/farmacologia , Preservação do Sêmen/veterinária , Ovinos , Espermatozoides/efeitos dos fármacos , Animais , Antioxidantes/química , Temperatura Baixa , Diarileptanoides/química , Gema de Ovo , Feminino , Fertilização , Inseminação Artificial/veterinária , Masculino , Casca de Planta , Gravidez , Análise do Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos
12.
Molecules ; 24(9)2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31075868

RESUMO

The valorization of lignins as renewable aromatic feedstock is of utmost importance in terms of the use of sustainable resources. This study provides a deductive approach towards market-oriented lignin-derived antioxidants by ascertaining the direct effect of different structural features of lignin on the reactivity of its phenolic OH groups in the radical scavenging reactions. The antioxidant activity of a series of compounds, modeling lignin structural units, was experimentally characterized and rationalized, using thermodynamic descriptors. The calculated O-H bond dissociation enthalpies (BDE) of characteristic lignin subunits were used to predict the modification pathways of technical lignins. The last ones were isolated by soda delignification from different biomass sources and their oligomeric fractions were studied as a raw material for modification and production of optimized antioxidants. These were characterized in terms of chemical structure, molecular weight distribution, content of the functional groups, and the antioxidant activity. The developed approach for the targeted modification of lignins allowed the products competitive with two commercial synthetic phenolic antioxidants in both free radical scavenging and stabilization of thermooxidative destruction of polyurethane films.


Assuntos
Antioxidantes/síntese química , Teoria da Densidade Funcional , Lignina/química , Modelos Teóricos , Dimerização , Elétrons , Hidrogênio/química , Cinética , Polifenóis/química , Poliuretanos/química , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
13.
Food Res Int ; 115: 200-208, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599932

RESUMO

The use of zero-waste processes to integrate food-waste valorisation into the circular economy equation is currently one of the hottest topics in sustainability research. This goal is still far from being fully achieved despite the release of a number of patents and papers that deal with the topic. The present work aims to valorise cocoa shells, one of the main by-product of the roasting process, in order to enhance the effective extraction of high added value compounds by means of green protocols. The high potential added value of the residual waste has been demonstrated via a direct analytical comparison of extracts and bean composition. A range of raw matrix extraction procedures have been investigated in order to define the best solvent and technology; ultrasound (US) and hydrodynamic cavitation (HC) were compared with conventional methods. The high-energy microenvironments generated by cavitation substantially promote fast biomass deconstruction with low energy consumption. The optimized protocol couples a HC reactor with a ternary water/ethanol/hexane mixture, simultaneously providing a hydrophilic product, which is rich in methylxanthines and polyphenols, and a lipid layer. Sequential milling and sieving pretreatment provided an enriched shell fraction via the partial removal of husk fibres (54.45 vs. 81.36 w/w % total fibres). The disposal of the latter reduces mass balance, but is rerouted into animal feedstock components and crop mulching. The protocols herein reported produce valuable extracts, which are rich in antioxidant flavanols (catechins and epicatechins), theobromine (32.7 ±â€¯0.12 mg/g shells), caffeine (1.76 ±â€¯0.08 mg/g shells) and cocoa butter, in a simple and easy manner. This new valorisation process afforded 20.5 w/w % and 15.8 w/w % hydrophilic and lipophilic fractions, respectively, when scaled up to function in a pilot flow reactor. The fatty acids, obtained in remarkable yield (forming the 96.4 w/w % of the total light part) well match the commercial cocoa butter profile. The antioxidant extract shows an impressive total phenolic content of 197.4 mg/g extract (gallic acid eq.), with a radical scavenging activity of 62.0 ±â€¯3.1 µg/mL (expressed in DPPH EC50). This work should facilitate industrial design for the convenient recovery of cocoa by-products as part of a zero-waste strategy.


Assuntos
Cacau/química , Extratos Vegetais/química , Resíduos , Ração Animal , Antioxidantes/análise , Biomassa , Carboidratos/análise , Catequina/análise , Flavanonas/análise , Indústria Alimentícia , Fenóis/análise , Polifenóis/análise , Solventes , Teobromina/análise , Xantinas
14.
Data Brief ; 22: 56-64, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30581905

RESUMO

Full analytical data of Ecuadorian cocoa wastes (raw shells) and beans (as benchmark), are herein reported. A detailed characterization of production residues may pave the road to a zero-waste strategy for the cocoa industry. Multiple analytical techniques have been exploited to define the composition of the matrices, among them: elemental analyses, FTIR, Py-GC/MS/FID and UHPLC-ESI-MS/MS. Quali-quantitative data of carbohydrates, lipids, lignin, polyphenols, alkaloids and proteins have been obtained by Py-GC/MS/FID and UHPLC-ESI-MS/MS. Assignations are fully supported by literature references. The FAMEs composition of lipophilic UAE extract is also reported for sake of comparison with cocoa butter. This data collection completes a wider valorization work, "Cocoa bean shell waste valorisation; extraction from lab to pilot-scale cavitational reactors" (Grillo et al., 2018).

15.
J Enzyme Inhib Med Chem ; 33(1): 1055-1063, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29877148

RESUMO

Oregonin is an open-chain diarylheptanoid isolated from Alnus incana bark that possesses remarkable antioxidant and anti-inflammatory properties, inhibits adipogenesis, and can be used in the prevention of obesity and related metabolic disorders. Here, we aimed to investigate the effects of oregonin on the epigenetic regulation in cells as well as its ability to modulate DNA methylating enzymes expression and mitochondrial DNA (mtDNA) copies. Our results show that oregonin altered the expression of DNA methyltransferases and mtDNA copy numbers in dependency on concentration and specificity of cells genotype. A close correlation between mtDNA copy numbers and mRNA expression of the mtDnmt1 and Dnmt3b was established. Moreover, molecular modeling suggested that oregonin fits the catalytic site of DNMT1 and partially overlaps with binding of the cofactor. These findings further extend the knowledge on oregonin, and elucidate for the first time its potential to affect the key players of the DNA methylation process, namely DNMTs transcripts and mtDNA.


Assuntos
Alnus/química , DNA (Citosina-5-)-Metiltransferase 1/biossíntese , DNA (Citosina-5-)-Metiltransferases/biossíntese , DNA Mitocondrial/metabolismo , Diarileptanoides/farmacologia , Fibroblastos/efeitos dos fármacos , Casca de Planta/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA/efeitos dos fármacos , Diarileptanoides/química , Diarileptanoides/isolamento & purificação , Relação Dose-Resposta a Droga , Camundongos , Estrutura Molecular , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Relação Estrutura-Atividade , DNA Metiltransferase 3B
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