Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
J Complement Integr Med ; 21(1): 26-37, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38180845

RESUMO

OBJECTIVES: Nigeria ranks second in the global prevalence of diarrhoea with most cases concentrated in the Northern-region of the country. This research explored the antidiarrhoeal efficacy of the hydroethanolic extract of Piliostigma thonningii leaves (HEPTL), locally used to manage diarrhoeal conditions in Kebbi State, Nigeria. METHODS: P. thonningii leaves were screened for their secondary metabolites and mineral constituents. Using 3 standard-diarrhoea models, female Wistar rats completely-randomised into six-groups of six animals each were utilised for probing the antidiarrhoeal activity of HEPTL. Animals in groups I and II served as the negative and positive controls, whereas the rats in groups III, IV and V respectively received 50, 100, and 200 mg/kg body weight-(bw) of HEPTL. RESULTS: Six secondary metabolites and eight minerals were found in the extract, with flavonoids and calcium being the most abundant while steroids and zinc were the least prevalent, respectively. High performance liquid chromatographic analysis revealed the presence of 19 bioactive substances. Furthermore, there was a significant (p<0.05) and dose-related reduction in diarrhoea onset, water content, and wet faeces count. Similarly, the amount of intestinal fluid and average distance traversed by the charcoal-meal were decreased dose-dependently by the HEPTL with a commensurate rise in the suppression of intestinal fluid accrual and peristalsis. Acetylcholinesterase, Na+/K+-ATPase, reduced glutathione, intestinal-alkaline phosphatase and protein levels increased significantly (p<0.05) whereas superoxide-dismutase, catalase, intestinal-nitric oxide and malondialdehyde levels all fell significantly (p<0.05). However, the level of intestinal glucose was not significantly altered. CONCLUSIONS: Overall, the HEPTL exhibited a profound effect in the alleviation of the severity of diarrhoea, notably at 200 mg/kg bw.


Assuntos
Antidiarreicos , Fabaceae , Ratos , Feminino , Animais , Ratos Wistar , Antidiarreicos/farmacologia , Antidiarreicos/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/análise , Fitoterapia , Acetilcolinesterase , Óleo de Rícino/análise , Óleo de Rícino/uso terapêutico , Diarreia/tratamento farmacológico , Fabaceae/química , Folhas de Planta/química
2.
Mol Biol Rep ; 50(12): 9859-9873, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37848759

RESUMO

BACKGROUND: Castor (Ricinus communis L.) seeds contain a large amount of oil that has several biological activities. In the current research, phytogeographic distribution, seed morphological characteristics, molecular genetic diversity and structure, and fatty acid composition were investigated in nine Iranian castor populations. METHODS AND RESULTS: The cetyltrimethylammonium bromide (CTAB) protocol was used to extract the nuclear genomes. These were later amplified using 13 SCoT molecular primers. The phytogeographic distribution was determined based on the Zohary mapping, GC apparatus determined the fatty acid composition of the seeds. GenAlex, STRUCTURE, GenoDive, PopGene, and PopART software were used for the statistical analyzes. On phytogeographic mapping, the harvested populations belonged to different districts of the Euro-Siberian and Irano-Turanian regions (Holarctic kingdom). Most of the quantitative morphological traits of the seeds differed significantly (P ≤ 0.05) between the populations. The AMOVA test demonstrated a large proportion of significant genetic diversity assigned among populations, which were approved by some estimated parameters of genetic diversity such as Nm, Ht, Hs, and Gst. Nei's genetic distance and structure analysis confirmed the existence of two main genotype groups and some intermediates. However, there was no isolation by distance between the genotypes. Unsaturated fatty acids were detected as the main component of seed oil with linoleic and ricinoleic acids. Significant correlations were detected between the main fatty acids of seed oil with seed morphological traits, geographic distance and the geographic parameters of habitats. According to the composition of the seed fatty acids, four chemotypes groups were detected. CONCLUSIONS: The classification patterns of the populations based on molecular genetic data, fatty acid composition, and phytogeographic mapping were not identical. These findings indicated that Iranian castor populations had unusual seed fatty acid composition which strongly depended on habitat geographic factors and seed morphological traits. However, the identified chemotypes and genotypes can be used in future breeding programs.


Assuntos
Euphorbiaceae , Ácidos Graxos , Ácidos Graxos/análise , Irã (Geográfico) , Melhoramento Vegetal , Óleo de Rícino/análise , Ricinus/genética , Sementes/genética , Sementes/química , Biologia Molecular
3.
Cornea ; 42(12): 1562-1571, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37506368

RESUMO

PURPOSE: The effect of skin lipids on the formation and stability of the human tear film was investigated. METHODS: Skin swab substances (SSSs) were applied to the eyes of volunteers and studied using fluorescein or with TearView, which records infrared emissivity showing tear film integrity in real time. Results were compared with similar experiments using castor oil, freshly collected meibum, or acetic acid, which simulated the low pH of the skin. RESULTS: Fluorescein and TearView results were comparable. TearView showed the natural unaltered tear film over the whole eye, instant changes to the tear film, and meibomian gland activity. Minimal amounts of SSS destroyed the integrity of the film and caused pain. Corneal epithelial damage could be detected. TearView showed that SSS stimulated meibomian gland secretion if applied directly to the posterior eyelid margin. Excess meibum had no effect on the tear film spread or integrity. Castor oil formed floating lenses on the tear film which were spread by a blink but then condensed back toward themselves. There was no pain or surface damage with these oils. CONCLUSIONS: SSS contamination of the ocular surface disrupts the tear film, causes stinging, and fluorescein staining of the corneal epithelial cells after a blink. SSS stimulates meibomian gland activity. It is possible that various ocular conditions associated with dry eye, such as blepharitis and ocular rosacea, may compromise a meibomian lipid barrier of the eye lid margin. Skin lipids would then have access to the ocular surface and cause dry eye symptoms.


Assuntos
Síndromes do Olho Seco , Lacerações , Humanos , Lágrimas/química , Óleo de Rícino/análise , Óleo de Rícino/farmacologia , Glândulas Tarsais , Síndromes do Olho Seco/etiologia , Fluoresceína/farmacologia
4.
Food Res Int ; 111: 399-407, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30007702

RESUMO

In this paper, the role of solvent characteristics on the rheological and physicochemical properties of organogels was investigated using different techniques. Vegetable oils, such as rice, sunflower and castor oil were used as solvents, for producing organogels with monoglycerides of fatty acids or a mixture of fatty alcohols (policosanol) as gelators. Moreover, two non-edible oils (silicon and paraffin oil) were also used for analysing the properties of solvents completely different in nature with respect to the edible ones, for a better interpretation of the given results. Organogels were investigated from a rheological point of view and through a microscopic analysis, given by polarised light (POM) and atomic force (AFM) microscopy, and X-rays to study the crystallinity of the system. The IR technique was used to analyse the intermolecular interactions, resulting in interesting information about the effect of oil polarity on the driving forces promoting structuration. This investigation showed that when solvents of a similar chemical nature are used, their physical properties, mainly oil polarity, are strictly related to the properties of the organogel, such as the onset of crystallisation temperature, the stiffness of the final material and its crystallinity. Anyway, these physical parameters seem insufficient to describe properly the role of solvents when oils of a different chemical nature are compared.


Assuntos
Óleo de Rícino/análise , Óleo de Rícino/química , Óleo de Farelo de Arroz/análise , Óleo de Farelo de Arroz/química , Óleo de Girassol/análise , Óleo de Girassol/química , Géis , Peso Molecular , Óleos/análise , Óleos/química , Parafina/análise , Parafina/química , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier
5.
J Agric Food Chem ; 59(17): 9250-6, 2011 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-21838261

RESUMO

Castor has tremendous potential as a feedstock for biodiesel production. The oil content and fatty acid composition in castor seed are important factors determining the price for production and affecting the key fuel properties of biodiesel. There are 1033 available castor accessions collected or donated from 48 countries worldwide in the USDA germplasm collection. The entire castor collection was screened for oil content and fatty acid composition by nuclear magnetic resonance (NMR) and gas chromatography (GC), respectively. Castor seeds on the average contain 48.2% oil with significant variability ranging from 37.2 to 60.6%. Methyl esters were prepared from castor seed by alkaline transmethylation. GC analysis of methyl esters confirmed that castor oil was composed primarily of eight fatty acids: 1.48% palmitic (C16:0), 1.58% stearic (C18:0), 4.41% oleic (C18:1), 6.42% linoleic (C18:2), 0.68% linolenic (C18:3), 0.45% gadoleic (C20:1), 84.51% ricinoleic (C18:1-1OH), and 0.47% dihydroxystearic (C18:0-2OH) acids. Significant variability in fatty acid composition was detected among castor accessions. Ricinoleic acid (RA) was positively correlated with dihydroxystearic acid (DHSA) but highly negatively correlated with the five other fatty acids except linolenic acid. The results for oil content and fatty acid composition obtained from this study will be useful for end-users to explore castor germplasm for biodiesel production.


Assuntos
Biocombustíveis , Óleo de Rícino/análise , Ácidos Graxos/análise , Ricinus communis , Sementes/química , Cromatografia Gasosa , Espectroscopia de Ressonância Magnética , Ácidos Ricinoleicos/análise , Estados Unidos , United States Department of Agriculture
6.
Braz. j. pharm. sci ; 46(3): 473-481, July-Sept. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-564913

RESUMO

The solubility behavior of drugs remains one of the most challenging aspects in formulation development. Solid Dispersion (SD) has tremendous potential for improving drug solubility. Although praziquantel (PZQ) is the first drug of choice in the treatment of schistosomiasis, its poor solubility has restricted its delivery oral route. In spite of its poor solubility, PZQ is well absorbed in the gastrointestinal tract, but large doses are required to achieve adequate concentration at the target sites. The aim of this study was to improve the solubility and dissolution rate of PZQ and to evaluate its intestinal absorption. SDs were formulated with PEG-60 castor oil hydrogenated (CR-60) using a fusion and evaporation method. Pure PZQ and physical mixtures (PM) and PZQ-CR-60 (2:1; 1:1; 1:2 ratios) were compared as regards their solubility, dissolution and intestinal absorption. The experimental results demonstrated the improvement in the solubility, dissolution rate and intestinal absorption. In addition, the solubility behavior showed pH dependency and that the solubility of PZQ was slower in acidic medium than in neutral and basic mediums. The increase in PZQ solubility of the SD with the CR-60 could be attributed to several factors such as improved wettability, local solubilization, drug particle size reduction and crystalline or, interstitial solid solution reduction.


A solubilidade de fármacos ainda é um dos principais desafios no desenvolvimento de formulações farmacêuticas. As dispersões sólidas (DS) apresentam grande potencial para melhorar a solubilidade de fármacos. O praziquantel é o fármaco de primeira escolha no tratamento da esquistossomose, contudo a baixa solubilidade em água restringe seu uso à administração pela via oral. Apesar da baixa solubilidade, o PZQ é bem absorvido através do trato gastrintestinal, mas doses orais elevadas são requeridas para garantir concentrações suficientes de fármaco para o tecido alvo. O objetivo deste estudo foi melhorar a solubilidade, a dissolução e avaliar a absorção do PZQ. As DS foram formuladas com óleo de castor hidrogenado - PEG 60 (CR-60), pelo uso dos métodos de fusão e evaporação do solvente. PZQ puro, mistura física (MF) e DS de CR-60-PZQ (1:2; 1:1; 2:1) foram comparados quanto à solubilidade, dissolução e absorção intestinal. Os resultados experimentais mostraram aumento na solubilidade, na taxa de dissolução e na absorção intestinal do PZQ nas DS. A solubilidade do PZQ foi maior em meio ácido, mostrando uma dependência do pH. O aumento na solubilidade do PZQ nas DS com CR-60 foi atribuída a fatores como aumento da molhabilidade, solubilização local, redução granulométrica e redução da cristalinidade ou, ainda, a ocorrência de uma solução sólida intersticial.


Assuntos
Fenômenos Químicos/estatística & dados numéricos , Dissolução/métodos , Emulsificantes , Óleo de Rícino/análise , Praziquantel/farmacologia , Hidrogenação , Interpretação Estatística de Dados
7.
Phytochemistry ; 71(8-9): 860-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20382402

RESUMO

Acyl-acyl carrier protein (ACP) thioesterases are enzymes that terminate the intraplastidial fatty acid synthesis in plants by hydrolyzing the acyl-ACP intermediates and releasing free fatty acids to be incorporated into glycerolipids. These enzymes are classified in two families, FatA and FatB, which differ in amino acid sequence and substrate specificity. In the present work, both FatA and FatB thioesterases were cloned, sequenced and characterized from castor (Ricinus communis) seeds, a crop of high interest in oleochemistry. Single copies of FatA and FatB were found in castor resulting to be closely related with those of Jatropha curcas. The corresponding mature proteins were heterologously expressed in Escherichia coli for biochemical characterization after purification, resulting in high catalytic efficiency of RcFatA on oleoyl-ACP and palmitoleoyl-ACP and high efficiencies of RcFatB for oleoyl-ACP and palmitoyl-ACP. The expression profile of these genes displayed the highest levels in expanding tissues that typically are very active in lipid biosynthesis such as developing seed endosperm and young expanding leaves. The contribution of these two enzymes to the synthesis of castor oil is discussed.


Assuntos
Ricinus communis/enzimologia , Tioléster Hidrolases/metabolismo , Ricinus communis/metabolismo , Óleo de Rícino/análise , Óleo de Rícino/biossíntese , Dados de Sequência Molecular , Estrutura Molecular , Análise de Sequência de Proteína , Homologia de Sequência do Ácido Nucleico
8.
Appl Biochem Biotechnol ; 156(1-3): 1-11, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19089650

RESUMO

The short supply of edible vegetable oils is the limiting factor in the progression of biodiesel technology; thus, in this study, we applied response surface methodology in order to optimize the reaction factors for biodiesel synthesis from inedible castor oil. Specifically, we evaluated the effects of multiple parameters and their reciprocal interactions using a five-level three-factor design. In a total of 20 individual experiments, we optimized the reaction temperature, oil-to-methanol molar ratio, and quantity of catalyst. Our model equation predicted that the following conditions would generate the maximum quantity of castor biodiesel (92 wt.%): a 40-min reaction at 35.5 degrees C, with an oil-to-methanol molar ratio of 1:8.24, and a catalyst concentration of 1.45% of KOH by weight of castor oil. Subsequent empirical analyses of the biodiesel generated under the predicted conditions showed that the model equation accurately predicted castor biodiesel yields within the tested ranges. The biodiesel produced from castor oil satisfied the relevant quality standards without regard to viscosity and cold filter plugging point.


Assuntos
Biotecnologia/métodos , Óleo de Rícino/análise , Fontes Geradoras de Energia , Controle de Qualidade , Temperatura , Fatores de Tempo
9.
J Sep Sci ; 27(3): 217-34, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15334909

RESUMO

Gas chromatography-mass spectrometry has been used to determine the nature of organic materials used in mummification balms. A comparative analysis of samples taken from Egyptian mummies is developed. The results are given in two parts. First, it is shown that the chemical composition of the balm is practically independent of the part of the mummy from which it is taken. This study was done on a Ptolemaic mummy (circa 100 BC from the Guimet Museum in Lyon). Fats, beeswax, and diterpenic resins were the main components: they were found everywhere. Castor oil was also very often detected (in half of the samples). This particular fat is present in the balm inside the thorax but not in the skull. Moreover it is shown that a vegetable tannin was employed. Components indicative of vegetable tannin input (gallic acid and inositols) were found in seven samples out of eighteen, particularly close to the body and on the canopic pack of the heart. Secondly, some conclusions from a comparative study of the composition of balms from mummies of various social levels as well as of different Egyptian periods are reported. It is shown that beeswax was used as from very early times (XVIIIth dynasty). The mixture of beeswax, fats, and diterpenoid resins would appear to be more recent. The balms of three mummies dating from more recent Egyptian periods (XIXth to XXVth dynasty) were analysed. No evidence of a resin, gum-resin, or plant gum could be found. Some mummies would appear to have been embalmed with fats or beeswax. Finally, the entrails canopic pack said to belong to Ramses II undoubtedly shows an embalming process with a triterpenic resin of the mastic type. The adopted analytical methodology enabled us to achieve simultaneous detection of four components of the balm of the Ptolemaic mummy. Analysis of the other five mummies revealed far less complex chemical compositions for the balms. This may be an indication of different embalming processes, although we should bear in mind the question of organic matter preservation through the ages.


Assuntos
Embalsamamento/história , Múmias/história , Óleo de Rícino/análise , Óleo de Rícino/história , Antigo Egito , Embalsamamento/métodos , Cromatografia Gasosa-Espectrometria de Massas , História Antiga , Humanos , Taninos Hidrolisáveis/análise , Taninos Hidrolisáveis/história , Resinas Vegetais/análise , Resinas Vegetais/história , Ceras/análise , Ceras/história
10.
J Agric Food Chem ; 52(1): 26-32, 2004 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-14709009

RESUMO

The aim of this work was to optimize a supercritical fluid extraction (SFE)/enzymatic reaction process for the determination of the fatty acid composition of castor seeds. A lipase from Candida antarctica (Novozyme 435) was used to catalyze the methanolysis reaction in supercritical carbon dioxide (SC-CO(2)). A Box-Behnken statistical design was used to evaluate effects of various values of pressure (200-400 bar), temperature (40-80 degrees C), methanol concentration (1-5 vol %), and water concentration (0.02-0.18 vol %) on the yield of methylated castor oil. Response surfaces were plotted, and these together with results from some additional experiments produced optimal extraction/reaction conditions for SC-CO(2) at 300 bar and 80 degrees C, with 7 vol % methanol and 0.02 vol % water. These conditions were used for the determination of the castor oil content expressed as fatty acid methyl esters (FAMEs) in castor seeds. The results obtained were similar to those obtained using conventional methodology based on solvent extraction followed by chemical transmethylation. It was concluded that the methodology developed could be used for the determination of castor oil content as well as composition of individual FAMEs in castor seeds.


Assuntos
Óleo de Rícino/análise , Ricinus communis/química , Sementes/química , Cromatografia com Fluido Supercrítico , Ésteres/análise , Ácidos Graxos/análise , Proteínas Fúngicas , Lipase/metabolismo , Metanol , Metilação
11.
Phytochem Anal ; 14(6): 337-46, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14667059

RESUMO

A non-aqueous reverse-phase HPLC method, based on two columns in series, has been used to separate the major triacylglycerols (TAGs) from commercial castor oil and to perform either on-line negative ion atmospheric pressure chemical ionisation (APCI), or off-line positive ion matrix-assisted laser desorption ionisation (MALDI)/MS. The resulting Mass Spectra showed chloride-attached TAG molecules [M + CI]- in the case of negative-ion APCI, and sodium-attached TAG molecules [M + Na]+ in the case of positive-ion MALDI. For MALDI time-of-flight (TOF)/MS, a liquid binary matrix system consisting of sodium ferrocyanide and glycerol was applied, resulting in excellent TAG sensitivity, which was necessary for the determination of trace amounts of TAGs in castor oil. Both techniques allowed unambiguous molecular mass determination of the intact TAG molecules with no thermal degradation. Furthermore, seamless post source decay (PSD) fragment ion analysis by means of a curved field reflector TOF mass spectrometer allowed the determination of the fatty acid composition of each individual TAG. Castor oil contained eight different TAGs which were successfully determined by both APCI and MALDI techniques. In each TAG, at least two units of 12-hydroxy-9-octadecenoic acid (ricinoleic acid) were present. The following fatty acids were determined by seamless PSD fragment ion analysis and APCI/MALDI molecular mass determination as TAG substructures: ricinoleic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, dihydroxy stearic acid and eicosenoic acid. Triricinolein was the dominating TAG.


Assuntos
Óleo de Rícino/química , Triglicerídeos/análise , Óleo de Rícino/análise , Cromatografia Líquida de Alta Pressão , Ácidos Graxos/análise , Peso Molecular , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
15.
J Pharm Sci ; 64(4): 674-80, 1975 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-238016

RESUMO

A sensitive, reproducible, fluorometric procedure for the determination of estrogens in pharmaceutical preparations is presented. The estrogens are determined fluorometrically following their reaction with dansyl chloride. The optimum conditions for the reaction such as pH, reaction solvent composition variations, and speed of reaction are discussed. In addition, a linearity study of the relationship between concentration and fluorescence intensity for estrone, estradiol, and ethinyl estradiol is reported. Solvent extraction procedures based on acid-base behavior or column chromatography are used when necessary to isolate the estrogen prior to reaction with dansyl chloride and fluorometric measurement. The recovery of estrogens from spiked samples indicated that the proposed method is efficient and reproducible. Comparison of the dansyl procedure with the official NF method in the analysis of estrone aqueous suspension showed the proposed method to be accurate and more precise than the NF assay. Estrone aqueous suspension, estradiol in sesame oil, estradiol valerate in castor oil and in sesame oil (in the latter case, in the presence of testosterone), estradiol benzoate in sesame oil, and ethinyl estradiol tablets (0.5 mg/tablet) from commercial sources were satisfactorily analyzed, with average results within compendial limits and no coefficient of variation greater than 2%.


Assuntos
Compostos de Dansil/análise , Estrogênios/análise , Óleo de Rícino/análise , Fenômenos Químicos , Química , Fluorometria , Concentração de Íons de Hidrogênio , Métodos , Óleo de Gergelim/análise , Soluções , Suspensões/análise , Comprimidos/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...