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1.
J Chromatogr A ; 1427: 111-24, 2016 Jan 04.
Article in English | MEDLINE | ID: mdl-26709070

ABSTRACT

A systematic study on the various sources of ion suppression in UHPLC-MS-MS analysis was carried out for 24 phenolic antioxidants in 6 different extracts of medicinal plants from Amazonia. The contributions of matrix effects, mobile-phase additives, analyte co-elution and electric charge competition during ionization to the global ion suppression were evaluated. Herein, the influence of mobile-phase additives on the ionization efficiency was found to be very pronounced, where ion suppression of approximately 90% and ion enhancement effects greater than 400% could be observed. The negative effect caused by the wrong choice of internal standard (IS) on quantitative studies was also evaluated and discussed from the perspective of ion suppression. This work also shows the importance of performing studies with this approach even for very similar matrices, such as varieties of medicinal plants from the same species, because different effects were observed for the same analyte.


Subject(s)
Antioxidants/analysis , Phenols/analysis , Plant Extracts/chemistry , Brazil , Catechin/analogs & derivatives , Catechin/analysis , Chromatography, Liquid/methods , Coumaric Acids/analysis , Coumarins/analysis , Flavonoids/analysis , Plants, Medicinal , Spectrometry, Mass, Electrospray Ionization/methods , Stilbenes/analysis , Tandem Mass Spectrometry/methods
2.
Rev. bras. plantas med ; 17(4,supl.1): 693-701, 2015. tab, graf
Article in English | LILACS | ID: lil-770368

ABSTRACT

ABSTRACT The plant Calendula officinalis L. is widely applied due to its medicinal properties, which are mainly dermatological and ornamental. The goal of this study is to assess the phytochemical components in a hydroethanolic extract (HECO) from the leaves of Calendula officinalis L. using UV-VIS spectrophotometry and thin layer chromatography (TLC), as well as to identify and quantify the components related to its antioxidant capacity employing high performance liquid chromatographic (HPLC). The antioxidant capacity evaluation was performed using the DPPH method for superoxide and hydroxyl radicals. The photo-protective capacity was evaluated by UVspectrophotometry in order to determine the in vitro Sun Protection Factor(SPF). The results show the plant’s strong antioxidant activity (DPPH and hydroxyl methods), which we believe to be related to the presence of flavonoids (24.67 mg/g), polyphenols (33.90 mg/g), condensed tannins (27.30 mg/g), and the amount of rutin (37.25 mg/g), and quercetin (6.09 mg/g) found during the study. The HECO presented a good antioxidant capacity, most likely due to the polyphenols, flavonoids, and tannins in its contents. However, the obtained SPF of 1.89 ± 0.05 does not allow the plant to be classified as a stand-alone sunscreen, and more studies are needed in order to test its ability to enhance sunscreens in existing cosmetic formulations.


RESUMO A Calendula officinalis L. é uma planta amplamente utilizada por suas propriedades medicinais, principalmente dermatológica e ornamental. O objetivo deste estudo é avaliar constituintes fitoquímicos do extrato hidroetanólico das folhas de Calêndula officinalis L. (HECO) por espectrofotometria UV-visível e cromatografia em camada delgada (CCD), bem como detectar e quantificar os componentes relacionados com a capacidade antioxidante por Cromatografia Líquida de Alta Eficiência (CLAE). Posteriormente, foi avaliada a capacidade antioxidante pelo método do DPPH, radicais superóxido e hidroxila. Além disso, a capacidade fotoprotetora foi avaliada através de espectrofotometria UV para determinação do Fator de Proteção Solar in vitro (FPS). Os resultados evidenciaram que a planta apresentou uma excelente atividade antioxidante para o método do DPPH e do radical hidroxila, o que pode estar relacionada com a presença de flavonoides (24,67 mg/g), polifenóis (33,90 mg/g) e taninos condensados (27,30 mg/g) e da quantidade de rutina (37,25 mg/g) e quercetina (6,09 mg/g) encontrados neste estudo. O HECO apresentou uma notável capacidade antioxidante, provavelmente devido à presença de polifenóis, flavonoides e taninos. O valor do FPS encontrado (1,89 ± 0,05), não classifica a planta como um protetor solar isolado. No entanto, mais estudos são necessários para testar a capacidade de potencializar filtros solares em formulações cosméticas.


Subject(s)
Calendula/classification , Phytochemicals/analysis , Antioxidants/pharmacology , Sunscreening Agents , Phenolic Compounds/analysis
3.
Article in English | MEDLINE | ID: mdl-22849359

ABSTRACT

Pharmaceutical adulterants are commonly found in herbal weight loss products, and analytical techniques for detecting these adulterants have become increasingly important to the public health community. Previously we reported a novel analytical method for the determination of adulterants in herbal formulations by capillary electrophoresis with contactless conductivity detection. The current study refines this previously described technique by testing if anxiolytics, diuretics, and laxatives interfered with the detection of anorectics and antidepressants. A survey of herbal weight loss products sold by compounding pharmacies in Brazil were analysed to determine the presence of pharmaceutical adulterants. A total of 106 herbal products, collected from 73 pharmacies in nine Brazilian states, were analysed for amfepramone, sibutramine, fenproporex, fluoxetine, paroxetine, sertraline and bupropion using the new analytical method. The method permitted the rapid and selective screening for the seven adulterants. Of the 106 weight loss products sampled, four (3.8%) were found to be adulterated by fenproporex or sibutramine. The adulterated samples were compounded by four different pharmacies located in three different Brazilian states. The novel capillary electrophoresis method we developed may be a useful tool for public health organisations tasked with analysing herbal weight loss products.


Subject(s)
Anti-Obesity Agents/chemistry , Dietary Supplements/analysis , Food Contamination , Food Inspection/methods , Plant Preparations/chemistry , Amphetamines/analysis , Anti-Anxiety Agents/analysis , Anti-Obesity Agents/adverse effects , Antidepressive Agents/analysis , Appetite Depressants/analysis , Brazil , Cyclobutanes/analysis , Dietary Supplements/adverse effects , Diuretics/analysis , Electric Conductivity , Electrophoresis, Capillary , Food Contamination/prevention & control , Laxatives/analysis , Plant Preparations/adverse effects
4.
Article in English | MEDLINE | ID: mdl-21424962

ABSTRACT

Trace element analysis plays an important role in oil characterisation and in the detection of oil adulteration because the quality of edible oils and fats is affected by their trace metal content. In this study, the quantification of selected metals in various oils and fats (rice oil, canola oil, sunflower oil, corn oil, soy oil, olive oil, light margarine, regular margarine and butter) was carried out using flame atomic absorption spectrometry (FAAS) and graphite furnace atomic absorption spectrometry (GFAAS) after sample emulsification. FAAS was used to determine the Na, K, Ca, Mg, Zn and Fe levels in the samples, while GFAAS was used for quantifying Cr, Ni, As, Pb, Cd, Cu and Mn, as these elements appeared in the samples at much lower concentrations. Tween-80 and Triton X-100 were employed as surfactants, and emulsions were prepared by a conventional method that involved heating and mixing of the constituents. Complete stabilisation was achieved through magnetic stirring for 15 min at room temperature. The evaluated figures of merit were linearity, accuracy and sensitivity, which were determined by the characteristic concentration and mass. Analysis of spiked samples demonstrated accuracy, which ranged from 90% (Na) to 112% (Fe) for FAAS and from 83% (Cd) to 121% (Pb) for GFAAS measurements. Atomic absorption spectrometry proved to be a promising approach for the analysis of metals in emulsified edible oils and fats. Additionally, under appropriate emulsification conditions (formulation, stirring time and temperature), the emulsions were homogeneous, had excellent stability, and had appropriate viscosity. The proposed method has proved to be simple, sensitive, reproducible, and economical.


Subject(s)
Butter/analysis , Emulsifying Agents/chemistry , Food Contamination , Margarine/analysis , Metals, Heavy/analysis , Plant Oils/chemistry , Trace Elements/analysis , Emulsions , Limit of Detection , Octoxynol/chemistry , Polysorbates/chemistry , Quality Control , Reproducibility of Results , Spectrophotometry, Atomic , Temperature , Time , Viscosity
5.
Forensic Sci Rev ; 23(2): 73-89, 2011 Jul.
Article in English | MEDLINE | ID: mdl-26231236

ABSTRACT

Alternative medicine has historically been very popular in developing countries. In this context, self-medication with herbal formulations has increased in both developing and developed nations in recent years. The adulteration of such formulations violates the laws of many countries because it can lead to unpredictable effects in the human body, either due to the isolated effects of an added pharmaceutical or to its interaction with other substances present in the formulation. The development of methodologies for the screening and quantification of adulterated samples should be of great interest for analytical, clinical, and forensic scientists. This review aims to provide a comprehensive approach to this topic and to discuss adulteration cases related to herbal formulations reported in the literature over the last few decades. Furthermore, a classification of the most commonly found synthetic adulterants that are linked to the active principle of herbal formulations was proposed according to their pharmacological action. The available analytical methodologies for the identification of adulteration practices are presented in a systematic and comprehensive way.

6.
Rev. bras. plantas med ; 13(spe): 527-532, 2011. tab
Article in Portuguese | LILACS | ID: lil-618326

ABSTRACT

Com o objetivo de avaliar a produtividade e qualidade do funcho (Foeniculum vulgare Mill.) produzido nas condições edafoclimáticas de Sergipe, foi conduzido cultivo orgânico de funcho em Frei Paulo-SE. Em junho de 2008 e de 2009, início do período de chuvas, foram instalados plantios por meio de mudas. Adicionalmente, em dezembro de 2010 foi realizada colheita de frutos a partir de plantas obtidas após poda drástica e rebrota. Foi realizada colheita de frutos e determinação da produtividade de dezembro a janeiro de 2008, 2009 e em dezembro de 2010. Verificou-se produtividade de 720 Kg.ha-1, no primeiro plantio e de 349 Kg.ha-1 no plantio de 2009. As plantas obtidas por rebrota em 2010 resultaram em produtividade de 589 Kg.ha-1. Sugere-se que a maior produtividade verificada no primeiro ano seja decorrente da maior precipitação média e conseqüente maior disponibilidade de água. A produtividade verificada nas plantas que rebrotaram em 2010 foi também superior a verificada em 2009, o que pode ser explicado tanto em função da maior precipitação, quanto em função do provável maior desenvolvimento das raízes e maior número de ramos após poda, devido à quebra da dominância apical. Esses dados sugerem importância da disponibilidade hídrica na determinação da produtividade na região e explicam a variação na produtividade verificada. A massa seca dos frutos (5, 29 g para 1000 frutos) e o alto teor de óleo essencial verificado (3,2 por cento), assim como a composição do óleo, revelam a alta qualidade dos frutos produzidos na região.


Aiming to evaluate the productivity and quality of fennel fruits produced in the countryside of Sergipe, with no irrigation, they were evaluated organic crops in Frei Paulo-SE. They were installed crops in 2008 and 2009 from seeds, on beginning rainy time. Seedlings obtained from seeds were transplanted in June 2008 and 2009. Besides, after the last harvest of the plants, grown in 2009, it was done a drastic pruning on plants, on May, 2010. The plants were held on the area until their fruits harvest, on december and January of 2008, 2009 and December 2010. The fennel fruits yield was 720 Kg ha -1 in the first crop (2008) and 349 Kg ha -1 at following crop (2009), while the fruits yield obtained from pruned plants was 589 Kg.ha-1. It is suggested that the higher yield at the first year has been due to the higher average rainfall and its greater availability of water. The observed yield in sprouted plants was higher (at 2010) than fennel yield of 2009. It can be explained as a function of precipitation, likely as a function of greater root development and increased number of branches and umbels after pruning and breaking of apical. These results reveal water availability importance to fennel yield. The dried mass of fruits (5.29 g to 1000 fruits), high content of essential oil in fruits (3.2 percent) and the essential oil composition reveal good quality of fennel fruits of Sergipe.


Subject(s)
Foeniculum/growth & development , Efficiency/classification , Plants, Medicinal , Semi-Arid Zone , Pimpinella/classification , Organic Agriculture/instrumentation
7.
J Trace Elem Med Biol ; 15(1): 46-55, 2001.
Article in English | MEDLINE | ID: mdl-11603827

ABSTRACT

Analytical results obtained by ICP-MS of hair samples from a group of women from Rio de Janeiro city show that abnormal Ca and P concentrations in this compartment can be an indication of pathologies affecting the metabolism of these elements. The study was conducted initially on 900 women (outpatients, >40 years). From this group, approx. 24% showed anomalously high or low Ca concentrations in hair, in some cases correlated to anomalies of other elements. In 144 cases (16%), very high concentrations of Ca (up to 8,285 mg/kg) were measured, frequently correlated with a high concentration of P (up to 4,720 mg/kg), exceeding by far the reference intervals for this age/sex group. Follow-up studies of a few individuals from this group gave first indications that their abnormal hair compositions were related to endocrinologic pathologies affecting calcium/bone metabolism. Very low hair Ca-concentrations were observed in older women (72 cases, age >60 years) and related to senile osteoporosis. Complementary investigations of patients with recognized endocrinologic pathologies (hyperthyroidism, hyper- and hypoparathyroidism) and osteomalacia gave statistical support for the hypothesis that hair concentrations of Ca, P and various other trace elements are influenced characteristically by these diseases. In patients with hyperparathyroidism and hyperthyroidism, both elements showed significant increase in hair, whereas patients with rickets/osteomalacia had only elevated Ca concentrations, together with suspiciously high toxic levels of Cd and various other elements (Fe, Mn, Mg, Sr, Ba). Patients with hypoparathyroidism had significantly decreased Ca and P concentrations in hair. Statistical evaluation of these data by multivariant analysis (MANOVA) using a contrast matrix and by discriminant analysis showed that elemental hair anomalies can be used to diagnose correctly the above-mentioned pathologies, demonstrating the usefulness of hair analysis as a complementary tool for the detection of disturbances in calcium/bone metabolism.


Subject(s)
Bone and Bones/metabolism , Calcium/deficiency , Endocrine System Diseases/metabolism , Hair/chemistry , Trace Elements/analysis , Adult , Aged , Biomarkers , Endocrine System Diseases/diagnosis , Female , Humans , Mass Spectrometry , Middle Aged
8.
Fresenius J Anal Chem ; 370(1): 92-6, 2001 May.
Article in English | MEDLINE | ID: mdl-11393244

ABSTRACT

A method has been developed for the chromatographic determination of methanethiol (MT) and ethanethiol (ET) as contaminants in amino acid parenteral nutrition (PN) solutions. The clean-up of the samples before chromatographic analysis was investigated by solid-phase extraction (SPE) on pre-columns filled with polyethylene powder (PE), aluminium oxide (AlOx), silica (SiOx), or polyurethane foam (PUF) as adsorbents. The thiols were more efficiently separated from the matrices by SPE on PUF pre-columns. Simultaneous derivatization and elution with DTNB (5,5'-dithiobis(2-nitrobenzoic acid)) enabled further discrimination between MT and ET by reversed-phase HPLC with spectrophotometric detection. The retention times for the derivatized MT and ET species were 12.5 and 23.0 min, respectively. Recoveries from spiked PN samples were calculated to be approximately 90%, and the MT and ET content of commercial PN solutions was determined using the methodology described. Detection limits of 15 and 10 microg L(-1) were calculated for MT and ET, respectively.


Subject(s)
Amino Acids/chemistry , Chromatography, High Pressure Liquid , Parenteral Nutrition/standards , Sulfhydryl Compounds/analysis , Aluminum Oxide/chemistry , Dithionitrobenzoic Acid/chemistry , Oxides/chemistry , Polyethylene/chemistry , Polyurethanes/chemistry , Silicon Compounds/chemistry
9.
Rev Soc Bras Med Trop ; 33(2): 163-8, 2000.
Article in Portuguese | MEDLINE | ID: mdl-10881128

ABSTRACT

We evaluated the clinical and therapeutic response to artesunate retocaps in 32 children admitted to the Fundação de Medicina Tropical do Amazonas (Amazon Foundation of Tropical Medicine) with clinical characteristics of moderate and severe malaria. Of these, 29 were infected with P. falciparum and 3 with P. vivax. They improved clinically 24 hours after the beginning of therapy, with 33. 3% of patients without fever, and after 48 hours, 77.2% of the children had no fever. The monitoring of asexual forms of the parasites showed that on D2 (day 2 of treatment) 58.6% of children with P. falciparum infection had no more parasites in the blood stream, on D4 all children had negative slides both for P. falciparum and for P. vivax infection. In a long-term follow up, we found 66.6% recrudescence in P. falciparum patients. The results enabled the conclusion that artesunate retocaps are efficient in practice and their use rapidly reduces the parasitemia and improves the patients' clinical picture. However, in P. falciparum malaria the recrudescence rate was very high. We observed no side effects from this drug.


Subject(s)
Antimalarials/therapeutic use , Artemisinins , Malaria, Falciparum/drug therapy , Malaria, Vivax/drug therapy , Sesquiterpenes/therapeutic use , Artesunate , Brazil , Child , Child, Preschool , Humans , Infant
10.
Planta Med ; 59(4): 369-72, 1993 Aug.
Article in English | MEDLINE | ID: mdl-17235992

ABSTRACT

The triterpenoid constituents of the chloroform extract of previously defatted material of the stems of SECURINEGA TINCTORIA were examined and, besides beta-sitosterol beta- D-glucopyranoside, a new oleanolic acid derivative was isolated and identified as 3beta( P-hydroxy- TRANS-cinnamoyloxy)olean-12-en-28-oicacid.

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