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1.
Molecules ; 29(2)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38276596

RESUMO

The main goal of this work was to develop analytical procedures for the isolation and determination of selected isothiocyanates. As an example, particularly sulforaphane from plants of the Brassicaceae Burnett or Cruciferae Juss family. The applied methodology was mainly based on classical extraction methods and high-performance liquid chromatography coupled with tandem mass spectrometry. Moreover, the effect of temperature on the release of isothiocyanates from plant cells was considered. The cytotoxic activity of the obtained plant extracts against a selected cancer cell line has also been included. The results allow evaluating the usefulness of obtained plant extracts and raw sprouts regarding their content of isothiocyanates-bioactive compounds with chemopreventive properties.


Assuntos
Antineoplásicos , Brassica , Brassica/química , Isotiocianatos/farmacologia , Isotiocianatos/química , Extratos Vegetais/química , Linhagem Celular , Sulfóxidos , Glucosinolatos/metabolismo
2.
Plants (Basel) ; 12(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36679068

RESUMO

In this study, phenolic compounds and their antioxidant activity in the pollen of anemophilous Betula and Pinus were determined. Spectrophotometric, high-performance thin-layer and liquid chromatography methods were applied. Free phenolic compounds (free PC) and phenolic compounds bound to the cell wall (bound PC) were analysed in the pollen extracts. Regardless of the pollen species, their content was 20% higher than that in bound PC extracts. Pinus pollen extracts contained 2.5 times less phenolic compounds compared to Betula. Free PC extraction from the deeper layers of Pinus pollen was minimal; the same content of phenolic compounds was obtained in both types of extracts. The bioactivity of pollen (p < 0.05) is related to the content of phenolic compounds and flavonoids in Betula free PC and in bound PC, and only in free PC extracts of Pinus. Rutin, chlorogenic and trans-ferulic acids were characterised by antioxidant activity. Phenolic acids accounted for 70−94%, while rutin constituted 2−3% of the total amount in the extracts. One of the dominant phenolic acids was trans-ferulic acid in all the Betula and Pinus samples. The specific compounds were vanillic and chlorogenic acids of Betula pollen extracts, while Pinus extracts contained gallic acid. The data obtained for the phenolic profiles and antioxidant activity of Betula and Pinus pollen can be useful for modelling food chains in ecosystems.

3.
Plants (Basel) ; 13(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38202407

RESUMO

Betula and Pinus pollen, which are dispersed in natural surface waters, release biologically active compounds into the water bodies. This study aims to evaluate variations in the distribution and composition of phenolic compounds in suspended particles in natural water bodies during pollen spreading. Samples taken from water bodies of different trophic levels were analyzed by microscopy, UV/VIS spectroscopy, HPTLC, and HPLC/DAD. The study revealed that the total phenolic content in water-suspended particles varied from 3.0 mg/g to 11.0 mg/g during Betula and Pinus pollen spreading. It was also observed that the surface water of dystrophic natural lakes had a higher content of phenolic compounds than the eutrophic, hypereutrophic, and mesotrophic water bodies. Chlorogenic, trans-ferulic, vanillin, and 3,4-dihydroxybenzoic acids were frequently detected in the surface water samples. Experimental measurements have shown variations in the release of phenolic compounds from Betula pollen into water (p < 0.05). After the exhibition of pollen, the distilled water predominantly contained bioactive chlorogenic acid. Further in situ investigations are necessary to gain a more comprehensive understanding of the function of phenolic compounds in aquatic ecosystems. The exploration of the release of bioactive compounds from pollen could provide valuable insights into the potential nutritional value of pollen as a nutrient source for aquaculture.

4.
Molecules ; 27(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36080242

RESUMO

The profiling and quantification of potentially toxic elements (PTEs) in honey from Poland was the main aim of this work. Due to the differences in botanical and geographical origin, 33 honey samples from various parts of Poland have been tested and compared to 12 samples taken from other countries, such as Australia, Bulgaria, Italy, Germany, Portugal, Romania and Turkey. The studied elements in honey samples were: As, Be, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sb, V and Zn. In most cases, the analyzed samples of honey were characterized by the moderate values of analyzed PTEs. Only a few samples contained higher concentrations of copper and manganese were noted. The presence of cadmium and lead in the level below the background equivalent concentrations was measured in the tested samples.


Assuntos
Mel , Metais Pesados , Oligoelementos , Cádmio/análise , Cobre , Monitoramento Ambiental , Mel/análise , Manganês , Metais Pesados/análise , Oligoelementos/análise
5.
Molecules ; 27(3)2022 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-35163995

RESUMO

In this review, recent advances in the methods of pre-treatment of plant material for the extraction of secondary metabolites with high biological activity are presented. The correct preparation of the material for extraction is as important as the selection of the extraction method. This step should prevent the degradation of bioactive compounds as well as the development of fungi and bacteria. Currently, the methods of preparation are expected to modify the particles of the plant material in such a way that will contribute to the release of bioactive compounds loosely bonded to cell wall polymers. This review presents a wide range of methods of preparing plant material, including drying, freeze-drying, convection drying, microwave vacuum drying, enzymatic processes, and fermentation. The influence of the particular methods on the structure of plant material particles, the level of preserved bioactive compounds, and the possibility of their release during the extraction were highlighted. The plant material pre-treatment techniques used were discussed with respect to the amount of compounds released during extraction as well their application in various industries interested in products with a high content of biologically active compounds, such as the pharmaceutical, cosmetics, and food industries.


Assuntos
Dessecação/métodos , Manipulação de Alimentos/métodos , Liofilização/métodos , Plantas/química , Preservação Biológica/métodos , Micro-Ondas , Vácuo
6.
Molecules ; 26(24)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34946786

RESUMO

Saponins are an important group of secondary metabolites naturally occurring in plants with important properties like: antibacterial, antiviral and antifungal. Moreover, they are widely used in the cosmetic industry and household chemistry. The sapogenins are saponin hydrolyses products, frequently used to facilitate saponin detection. In the present study, an improved methodology for isolation and separation of five sapogenins extracted from nettle (Urtica dioica L.), white dead-nettle (Lamium album L.), common soapwort (Saponaria officinalis L.) and washnut (Sapindus mukorossi Gaertn.) was developed using ultra-high-performance liquid chromatography with an evaporative light-scattering detector (UHPLC-ELSD). Based on quantitative analysis, the highest content of hederagenin (999.1 ± 6.3 µg/g) and oleanolic acid (386.5 ± 27.7 µg/g) was found in washnut extracts. Good recoveries (71% ± 6 up to 99% ± 8) were achieved for four investigated targets, while just 22.2% ± 0.5 was obtained for the fifth one. Moreover, hederagenin and oleanolic acid of whose highest amount was detected in washnut (999.1 ± 6.3 µg/g and 386.5 ± 27.7 µg/g, respectively) were subject to another approach. Consequently, liquid chromatography coupled mass spectrometry (LC/MS) with multiple reaction monitoring mode (MRM) was used as an additional technique for fast and simultaneous identification of the mentioned targets.


Assuntos
Sapindus/química , Sapogeninas/análise , Sapogeninas/isolamento & purificação , Saponaria/química , Urtica dioica/química
7.
Molecules ; 26(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34443322

RESUMO

The main aim of this study was to develop a method for the isolation and determination of polyphenols-in particular, flavonoids present in various morphological parts of plants belonging to the cabbage family (Brassicaceae). Therefore, a procedure consisting of maceration, acid hydrolysis and measurement of the total antioxidant capacity of plant extracts (using DPPH assay) was conducted. Qualitative analysis was performed employing thin-layer chromatography (TLC), which was presented to be a suitable methodology for the separation and determination of chemopreventive phytochemicals from plants belonging to the cabbage family. The study involved the analysis of 25 vegetal samples, including radish, broccoli, Brussels sprouts, kale, canola, kohlrabi, cabbage, Chinese cabbage, red cabbage, pak choi and cauliflower. In addition, selected flavonoids content in free form and bonded to glycosides was determined by using an RP-UHPLC-ESI-MS/MS method.


Assuntos
Brassicaceae/química , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/isolamento & purificação , Cromatografia em Camada Fina
8.
Molecules ; 25(24)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33317195

RESUMO

A method development for determination of neonicotinoid residues in honey samples was developed. The proposed methodology consisted in QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe). That was used for sample preparation and UHPLC/UV (ultra-performance liquid chromatography with ultraviolet detection) utilized for chromatographic analysis. The developed method proved to be sensitive, with LOD (Limit of detection) value in the range of 60.80 to 80.98 ng/g hence LOQ (Limit of quantification) value was in the range of 184.26 to 245.40 ng/g. The method has tested on Polish honey and applied to honey from various countries (Bulgaria, Czech Republic, France, Greece, Italy, Portugal, Romania, Australia, Brazil, Cameroon, Russia, USA and Turkey). Several honey types were tested, while physicochemical properties of all honeys and were investigated. The methodology for general characterization of pollen grains originated from selected plants, to confirm the type of honey was also presented. There was a total lack of the mentioned neonicotinoids in sunflower honey. Except of this, only two samples of rapeseed and two samples of acacia honey (from Poland and Romania) were neonicotinoids free. In 19 samples the targeted pesticides were detected above LOQ. In all other investigated samples, the neonicotinoids were found at least at the LOD or LOQ level.


Assuntos
Mel/análise , Neonicotinoides/análise , Animais , Austrália , Abelhas , Brasil , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Europa (Continente) , Flores/química , Inseticidas/análise , Inseticidas/química , Limite de Detecção , Neonicotinoides/química , Polônia , Pólen/química , Pólen/ultraestrutura , Polinização , Estados Unidos
9.
Molecules ; 25(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861887

RESUMO

Honey is a natural sweetener, with an osmotic effect on microorganisms due to the increased sugar content and low amount of water. Cyclitols are minor constituents of honey. They play a defensive role in plants against unfavorable environmental conditions. Honey's physicochemical properties can vary, resulting in a wide range of colors, flavors, scents, antioxidant activity, dissimilar values of pH, acidity, electrical conductivity, etc. Some literature regarding correlation between honey types is already available, but a comprehensive study displaying an ample evaluation of multifarious aspects is still needed. This study focuses on the correlation between 18 honey types, originating from 10 countries, collected during four years, summarizing a total of 38 samples. A total of 6 physicochemical properties and 18 target components (sugars and cyclitols) were considered as variables. A correlation analysis is presented between the investigated parameters and between honey types, together with the statistical analysis which allowed for observation of the clusters' distribution according with the investigated variables.


Assuntos
Ciclitóis/análise , Mel/análise , Açúcares/análise
10.
Environ Sci Pollut Res Int ; 26(34): 34723-34740, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31520389

RESUMO

Among pesticides and foliar sprays involved in the treatment of seed, soil, and grass, also to crops, an important group is neonicotinoids. Neonicotinoid pesticides present similar properties with nicotine, but the mentioned compounds are less harmful for humans. Nevertheless, neonicotinoids are poisonous to insects and some invertebrates, which can act against insects' central nervous system, leading to their death. Moreover, neonicotinoids can affect the reproduction, foraging, and flying ability of honeybee and other insects including pollinators. In the present study, some neonicotinoids, such as imidacloprid, acetamiprid, clothianidin, thiacloprid, and thiamethoxam together with their toxic effects, have been presented. The Environmental Protection Agency (EPA) classifies these neonicotinoids as II and III class toxicity agents. Due to accumulation of these pesticides into the pollen of treated plants, especially due to their toxic effects against pollinators, the consequences of the occurrence of these insecticides have been discussed. Analytical aspects and methods involved in the isolation and determination of this class of pesticides have been presented in this contribution.


Assuntos
Inseticidas , Neonicotinoides , Animais , Abelhas , Guanidinas , Humanos , Insetos , Invertebrados , Nitrocompostos , Solo , Tiametoxam , Tiazinas , Tiazóis
11.
Chirality ; 31(2): 138-149, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30609133

RESUMO

Plant material is a rich source of valuable compounds such as flavanones. Their different forms influence bioavailability and biological activity, causing problems with the selection of plant material for specific purposes. The purpose of this research was to determine selected flavanone (eriodictyol, naringenin, liquiritigenin, and hesperetin) enantiomer contents in free form and bonded to glycosides by an RP-UHPLC-ESI-MS/MS method. Different parts (stems, leaves, and flowers) of goldenrod (Solidago virgaurea L.), lucerne (Medicago sativa L.), and phacelia (Phacelia tanacetifolia Benth.) were used. The highest content of eriodictyol was found in goldenrod flowers (13.1 µg/g), where it occurred mainly as the (S)-enantiomer, and the greatest proportion of the total amount was bonded to glycosides. The richest source of naringenin was found to be lucerne leaves (4.7 µg/g), where it was mainly bonded to glycosides and with the (S)-enantiomer as the dominant form. Liquiritigenin was determined only in lucerne, where the flowers contained the highest amount (1.2 µg/g), with the (R)-enantiomer as dominant aglycone form and the (S)-enantiomer as the dominant glycosylated form. The highest hesperetin content was determined in phacelia leaves (0.38 µg/g), where it was present in the form of a glycoside and only as the (S)-enantiomer. A comparison of the different analyte forms occurring in different plant parts was performed for the first time.


Assuntos
Boraginaceae/metabolismo , Flavonoides/química , Flavonoides/metabolismo , Medicago sativa/metabolismo , Solidago/metabolismo , Glicosídeos/química , Estereoisomerismo
12.
Nutrients ; 10(12)2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30513929

RESUMO

INTRODUCTION: Myo-inositol and its derivatives cyclitols play an important role in the processes of cell regulation, signal transduction, osmoregulation, and ion channel physiology, and are a component of the cell membrane. Free cyclitols present in food or released during the degradation of galactosyl cyclitols by bacteria (in digestive tract) show some physiological benefits. AIM: The aim of this paper is to present and analyze the documented data about curative and healing properties of cyclitols. RESULTS AND DISCUSSION: Cyclitols are well known compounds in the treatment of an accompanied diabetes insulin resistance, and also obesity and polycystic ovarian syndrome. d-chiro-Inositol deficiency exacerbates insulin resistance in the liver, muscles, and fat, while depletion of myo-inositol results in the development of diabetic complications. Cyclitols are successfully applied in treatment of polycystic ovarian syndrome, simultaneous are observed effective reducing of BMI, improving the hormonal profile, and increasing fertility. Moreover, cyclitols have anti-atherogenic, anti-oxidative, anti-inflammatory, and anti-cancer properties. CONCLUSION: The properties of cyclitols may be a good therapeutic option in the reduction of metabolically induced inflammation. Due to well drugs tolerance and low toxicity of these compounds, cyclitols are recommend for pregnant women and also for children. Another advantage is their widespread presence and easy availability, which encourages their use in medicine.


Assuntos
Ciclitóis/farmacologia , Doenças Metabólicas/tratamento farmacológico , Configuração de Carboidratos , Ciclitóis/química , Humanos , Doenças Metabólicas/metabolismo
13.
Phytochem Anal ; 29(5): 528-537, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29732635

RESUMO

INTRODUCTION: Alfalfa (Medicago sativa L.) is the subject of many studies due to its numerous chemical constituents and beneficial properties. Among these constituents are cyclitols, which have attracted attention due to the variety of biological properties they have. OBJECTIVE: A rapid and sensitive analytical procedure based on matrix-assisted laser desorption ionisation technique with time-of-flight and mass spectrometry (MALDI-TOF-MS) analysis was used for the first time for the identification of three cyclitols from different parts of alfalfa. METHODOLOGY: Plant extracts were prepared and purified using Soxhlet extraction and solid-phase extraction (SPE). Then, samples were dissolved in α-cyano-4-hydroxycinnamic acid (HCCA) matrix, and subjected to MALDI-TOF-MS analysis. RESULTS: The ion at m/z 524.0 was distributed in all standards and in leaves and stem extracts. In turn, the signal at m/z 335.1 was found in all standards and all alfalfa extracts. The ion at m/z144.1 was found just for d-chiro-inositol and distributed in all extracts. Both signals at m/z 265.9 and 250.0 were found only in l-chiro-inositol standard and the extract of stem. However, the ion at m/z 177.1 was found in d-pinitol standard and the extract of leaves. Based on molecular weights, information on fragment ions obtained by MALDI-TOF-MS, and the chemistry of cyclitols, we successfully identified three cyclitols (d-chiro-inositol, l-chiro-inositol, d-pinitol) in different parts of alfalfa (leaves, stem, flowers). CONCLUSION: The obtained results in this study proved that MALDI-TOF-MS is a rapid, sensitive and very powerful tool for identification of cyclitols within plants and has the potential to differentiate between enantiomers.


Assuntos
Ciclitóis/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Limite de Detecção , Estruturas Vegetais/química , Padrões de Referência , Extração em Fase Sólida
14.
Electrophoresis ; 2018 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-29603754

RESUMO

Based on the bioactive properties of certain compounds, such as antioxidant and anti-inflammatory activities, an interesting subject of research are natural substances present in various parts of plants. The choice of the most appropriate method for separation and quantification of biologically active compounds from plants and natural products is a crucial step of any analytical procedure. The aim of this review article is to present an overview of a comprehensive literature study from the last 10 years (2007-2017), where relevant articles exposed the latest trends and the most appropriate methods applicable for separation and quantification of biologically active compounds from plant material and natural products. Consequently, various extraction methods have been discussed, together with the available procedures for purification and pre-concentration and dedicated methods used for analysis.

15.
Electrophoresis ; 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29543989

RESUMO

Cyclitols are phytochemicals naturally occurring in plant material, which attracted an increasing interest due to multiple medicinal attributes, among which the most important are the antidiabetic, antioxidant, and anticancer properties. Due to their valuable properties, sugars are used in the food industry as sweeteners, preservatives, texture modifiers, fermentation substrates, and flavoring and coloring agents. In this study, we report for the first time the quantitative analysis of sugars and cyclitols isolated from Solidago virgaurea L., which was used for the selection of the optimal solvent and extraction technique that can provide the best possible yield. Moreover, the quantities of sugars and cyclitols extracted from two other species, Solidago canadensis and Solidago gigantea, were investigated using the best extraction method and the most appropriate solvent. Comparative analysis of natural plant extracts obtained using five different techniques-maceration, Soxhlet extraction, pressurized liquid extraction, ultrasound-assisted extraction, and supercritical fluid extraction-was performed in order to decide the most suitable, efficient, and economically convenient extraction method. Three different solvents were used. Analysis of samples has been performed by solid-phase extraction for purification and pre-concentration, followed by derivation and GC-MS analysis. Highest efficiency for the total amount of obtained compounds has been reached by PLE, when water was used as a solvent. d-pinitol amount was almost similar for every solvent and for all the extraction techniques involved.

16.
J Sep Sci ; 41(5): 1118-1128, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29250921

RESUMO

Plant research interest has increased all over the world, and a large body of evidence has been collected to show the huge potential of medicinal plants in various disease treatments. Medicago sativa L., known as alfalfa, is a rich source of biologically active components and secondary metabolites and was frequently used from the ancient times both as fodder crop and as a traditional medicine in the treatment of various diseases. Cyclitols, naturally occurring in this plant, have a particular interest for us due to their significant anti-diabetic, antioxidant, anti-inflammatory, and anti-cancer properties. In the present study we revealed the isolation, the identification, and the quantification of some cyclitols and sugars extracted from different morphological parts of alfalfa plant. Soxhlet extraction and solid phase extraction were used as extraction and purification methods, while for the analyses derivatization followed by gas chromatography with mass spectrometry was involved. The obtained results showed significant differences in the quantities of cyclitols and sugars found in the investigated morphological parts, ranging between 0.02 and 13.86 mg/g of plant in case of cyclitols, and in the range of 0.09 and 40.09 mg/g of plant for sugars. However, roots have the richest part of cyclitols and sugars in contrast to the leaves.


Assuntos
Ciclitóis/análise , Medicago sativa/química , Componentes Aéreos da Planta/química , Açúcares/análise , Cromatografia Gasosa-Espectrometria de Massas , Extração em Fase Sólida
17.
J Sep Sci ; 39(4): 769-75, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26632088

RESUMO

Methods for the separation and determination of terpenes (mono- and sesqui-) and phenylpropanoids such as eugenol and methyleugenol from samples of allspice berries have been developed. Chromatographic analyses of isolated groups of compounds were carried out by means of gas chromatography coupled with mass spectrometry. A comparison of various types of solid-phase microextraction fibers was performed. The highest yields of terpenes were extracted by polydimethylsiloxane and divinylbenzene/Carboxen/polydimethylsiloxane fibers (almost the same for these two fibers), approximately twice as much as by Carbowax/divinylbenzene fiber. The highest amounts of monoterpenes were extracted by divinylbenzene/Carboxen/polydimethylsiloxane fiber, and the highest amounts of sesquiterpenes were extracted by polydimethylsiloxane fiber. Moreover, the effect of water addition on extraction yields as well as time and temperature of extraction were tested. Aroma profiles of extracts obtained by solid-phase microextraction and essential oil obtained by hydrodistillation of allspice berries were compared. The aroma profile of the divinylbenzene/Carboxen/polydimethylsiloxane fiber extract was similar to the aroma profile of essential oil. Particular characteristics of volatile allspice matters were presented. The linear retention indices for each compound were calculated.


Assuntos
Pimenta/química , Microextração em Fase Sólida/métodos , Terpenos/análise , Água/química , Dimetilpolisiloxanos/química , Destilação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Monoterpenos/química , Óleos Voláteis , Polietilenoglicóis/química , Sesquiterpenos/química , Temperatura , Terpenos/química , Compostos de Vinila/química
18.
Biomed Chromatogr ; 29(4): 584-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25201261

RESUMO

The aim of this study was to develop and validate a new analytical method for the determination of 4-hydroxy-2-nonenal (4-HNE) in biological samples while applying microextraction by packed sorbent as a sample preparation method and HPLC with UV-vis detection. Various microextraction by packed sorbent (MEPS) sorbents like C2 , C8 , C18 , M1 (80% C8 and 20% SCX) and silica were used to separate 4-HNE from biological samples. The highest affinity of 4-HNE was observed for sorbents like C18 . The extraction efficiency was in the range from 47.4 to 89.2% dependent on the concentration of 4-HNE. Lower efficiency of 4-HNE extraction was obtained with use of MEPS packings such as C8 and M1. The extraction efficiency was in the range from 35.2 to 66.3% for packing C8 and from 34.2 to 64.3% for packing M1, respectively. The limit of detection and lower limit of quantitation for UV-vis detection were respectively 4.5 and 9.0 nmol/mL. The proposed method can be used for the evaluation of extraction efficiency of 4-HNE in biological sample because the values of lower limit of quantitation are lower than the determined amounts of the analyte in samples. The method yields excellent performance of quantification and identification in analysis of inflammation biomarkers.


Assuntos
Aldeídos/química , Cromatografia Líquida de Alta Pressão/métodos , Microextração em Fase Sólida/métodos , Adsorção , Aldeídos/isolamento & purificação , Biomarcadores/química , Cromatografia Líquida de Alta Pressão/instrumentação , Microextração em Fase Sólida/instrumentação
19.
Anal Bioanal Chem ; 402(7): 2233-48, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22015476

RESUMO

Lyme borreliosis (LB) is one of the most common tick-borne diseases in the northern hemisphere. It is a chronic inflammatory disease caused by the spirochaete Borrelia burgdorferi. In its early stages, pathological skin lesions, namely erythema chronicum migrans, appear. The lesions, usually localised at the site of the bite, may become visible from a few weeks up to 3 months after the infection. Predominant clinical symptoms of the disease also involve joint malfunctions and neurological or cardiac disorders. Lyme disease, in all its stages, may be successfully treated with antibiotics. The best results, however, are obtained in its early stages. In order to diagnose the disease, numerous medical or laboratory techniques have been developed. They are applied to confirm the presence of intact spirochaetes or spirochaete components such as DNA or proteins in tick vectors, reservoir hosts or patients. The methods used for the determination of LB biomarkers have also been reviewed. These biomarkers are formed during the lipid peroxidation process. The formation of peroxidation products generated by human organisms is directly associated with oxidative stress. Apart from aldehydes (malondialdehyde and 4-hydroxy-2-nonenal), many other unsaturated components such as isoprostenes and neuroprostane are obtained. The fast determination of these compounds in encephalic fluid, urine or plasma, especially in early stages of the disease, enables its treatment. Various analytical techniques which allow the determination of the aforementioned biomarkers have been reported. These include spectrophotometry as well as liquid and gas chromatography. The analytical procedure also requires the application of a derivatization step by the use of selected reagents.


Assuntos
Biomarcadores/análise , Doença de Lyme/diagnóstico , Humanos , Doença de Lyme/microbiologia
20.
BMC Cancer ; 9: 348, 2009 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-19788722

RESUMO

BACKGROUND: Lung cancer is one of the leading causes of death in Europe and the western world. At present, diagnosis of lung cancer very often happens late in the course of the disease since inexpensive, non-invasive and sufficiently sensitive and specific screening methods are not available. Even though the CT diagnostic methods are good, it must be assured that "screening benefit outweighs risk, across all individuals screened, not only those with lung cancer". An early non-invasive diagnosis of lung cancer would improve prognosis and enlarge treatment options. Analysis of exhaled breath would be an ideal diagnostic method, since it is non-invasive and totally painless. METHODS: Exhaled breath and inhaled room air samples were analyzed using proton transfer reaction mass spectrometry (PTR-MS) and solid phase microextraction with subsequent gas chromatography mass spectrometry (SPME-GCMS). For the PTR-MS measurements, 220 lung cancer patients and 441 healthy volunteers were recruited. For the GCMS measurements, we collected samples from 65 lung cancer patients and 31 healthy volunteers. Lung cancer patients were in different disease stages and under treatment with different regimes. Mixed expiratory and indoor air samples were collected in Tedlar bags, and either analyzed directly by PTR-MS or transferred to glass vials and analyzed by gas chromatography mass spectrometry (GCMS). Only those measurements of compounds were considered, which showed at least a 15% higher concentration in exhaled breath than in indoor air. Compounds related to smoking behavior such as acetonitrile and benzene were not used to differentiate between lung cancer patients and healthy volunteers. RESULTS: Isoprene, acetone and methanol are compounds appearing in everybody's exhaled breath. These three main compounds of exhaled breath show slightly lower concentrations in lung cancer patients as compared to healthy volunteers (p < 0.01 for isoprene and acetone, p = 0.011 for methanol; PTR-MS measurements). A comparison of the GCMS-results of 65 lung cancer patients with those of 31 healthy volunteers revealed differences in concentration for more than 50 compounds. Sensitivity for detection of lung cancer patients based on presence of (one of) 4 different compounds not arising in exhaled breath of healthy volunteers was 52% with a specificity of 100%. Using 15 (or 21) different compounds for distinction, sensitivity was 71% (80%) with a specificity of 100%. Potential marker compounds are alcohols, aldehydes, ketones and hydrocarbons. CONCLUSION: GCMS-SPME is a relatively insensitive method. Hence compounds not appearing in exhaled breath of healthy volunteers may be below the limit of detection (LOD). PTR-MS, on the other hand, does not need preconcentration and gives much more reliable quantitative results then GCMS-SPME. The shortcoming of PTR-MS is that it cannot identify compounds with certainty. Hence SPME-GCMS and PTR-MS complement each other, each method having its particular advantages and disadvantages. Exhaled breath analysis is promising to become a future non-invasive lung cancer screening method. In order to proceed towards this goal, precise identification of compounds observed in exhaled breath of lung cancer patients is necessary. Comparison with compounds released from lung cancer cell cultures, and additional information on exhaled breath composition in other cancer forms will be important.


Assuntos
Testes Respiratórios/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Neoplasias Pulmonares/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Expiração , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Adulto Jovem
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