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PL
Celem badań było oznaczenie stężenia kofeiny oraz dodatkowo teobrominy i teofiliny w dostępnych na polskim rynku napojach energetycznych, a następnie porównanie uzyskanych wartości stężeń kofeiny z danymi podawanymi przez producentów popularnych „energetyków” oraz obliczenie szacunkowego dziennego spożycia kofeiny oraz pozostałych oznaczonych alkaloidów w zależności od spożywanej porcji napoju czy wagi konsumenta w celu określenia potencjalnego ryzyka zdrowotnego dla człowieka. Po odpowiednim przygotowaniu próbki do badań wykonano oznaczenia wybranych analitów przy wykorzystaniu techniki wysokosprawnej chromatografii cieczowej w odwróconym układzie faz z detektorem działającym w zakresie ultrafioletu i światła widzialnego (RP-HPLC-UV-VIS). Przeprowadzone badania napojów energetycznych wykazały obecność nie tylko kofeiny, ale także innych alkaloidów o działaniu podobnym do kofeiny, których obecność nie jest podawana na opakowaniach (teobrominy i teofiliny), a sumaryczna zawartość tych trzech alkaloidów przekraczała zawartość kofeiny podaną przez producenta. Dzięki oszacowaniu dziennego spożycia poszczególnych alkaloidów wykazano, że spożycie napoju w objętości większej niż 250 ml może powodować negatywne skutki dla zdrowia człowieka, zwłaszcza problemy związane ze snem.
EN
The aim of the study was to determine the content of caffeine and also theobromine and theophylline in energy drinks available on the Polish market, and then to compare the obtained values of caffeine content to the values provided by the manufacturers of popular energy drinks and to calculate the estimated daily intake (EDI) of caffeine and other alkaloids based on the volume of consumed drink or weight of a consumer to asses a potential health risk for humans. After properly preparing the samples for the analysis, the selected analytes were analysed using reverse phase high performance liquid chromatography with detection in ultraviolet and visible light spectrum (RP-HPLC-UV-VIS). The conducted analysis of energy drinks showed the presence of not only caffeine, but also of other alkaloids with similar effects as caffeine, whose presence is not mentioned on the energy drinks labels (theobromine and theophylline). The total content of these three alkaloids was higher than the values for caffeine provided by the manufacturers. The calculated estimated daily intake of alkaloids demonstrated that consuming more than 250 ml of energy drink can have a negative impact on human health, especially contributing to sleep problems.
2
Content available Plant secondary metabolites as defenses : a review
EN
Plant secondary metabolites have a variety of functions, including mediating relationships between organisms, responding to environmental challenges, and protecting plants against infections, pests, and herbivores. In a similar way, through controlling plant metabolism, plant microbiomes take part in many of the aforementioned processes indirectly or directly. Researchers have discovered that plants may affect their microbiome by secreting a variety of metabolites, and that the microbiome could likewise affect the metabolome of the host plant. Pesticides are agrochemicals that are employed to safeguard humans and plants from numerous illnesses in urban green zones, public health initiatives, and agricultural fields. The careless use of chemical pesticides is destroying our ecology. As a result, it is necessary to investigate environmentally benign alternatives to pathogen management, such as plant-based metabolites. According to literature, plant metabolites have been shown to have the ability to battle plant pathogens. Phenolics, flavonoids, and alkaloids are a few of the secondary metabolites of plants that have been covered in this study.
PL
Europejski Urząd ds. Bezpieczeństwa Żywności (EFSA) stale aktualizuje i uzupełnia wyniki naukowej oceny bezpieczeństwa w zakresie zanieczyszczeń w żywności. Na tej podstawie organy decyzyjne UE i przedstawiciele władz państw członkowskich opracowują oraz przyjmują akty prawne w celu zapewnienia bezpieczeństwa żywności i ochrony zdrowia konsumentów. W artykule przedstawiono prace prowadzone obecnie przez EFSA, Komisję Europejską oraz Stały Komitet ds. Roślin, Zwierząt, Żywności i Pasz, a także najnowsze zmiany w unijnych regulacjach prawnych w odniesieniu do zanieczyszczeń w żywności. Omówiono cztery grupy zanieczyszczeń: procesowe, mikrobiologiczne, chemiczne i toksyny pochodzenia roślinnego lub produkowane przez grzyby.
EN
The European Food Safety Authority (EFSA) is continuously updating and supplementing the scientific safety assessment related to contaminants in food. On this basis, legal acts aimed at ensuring food safety and protecting consumers’ health are developed and adopted by the EU decision-making bodies and representatives of the Member States’ authorities. The article presents the current work of the EFSA, the European Commission and Standing Committee on Plants, Animals, Food and Feed, as well as the recent developments in the EU law in respect of food contaminants. Four groups of contaminants are discussed: process, microbiological, chemical contaminants and toxins of plant origin and produced by fungi.
PL
Postępujący wzrost antropopresji przyczynia się do powstawania strumieni nowych substancji wprowadzanych do ekosystemu. Ich właściwości oraz wpływ na otoczenie bardzo często są nieznane. Z tego powodu zawartość tych związków powinna podlegać monitorowaniu. Jednakże opracowanie skutecznej metodyki umożliwiającej oznaczenie niewielkich ilości tych indywiduów chemicznych w skomplikowanych matrycach jest nie lada wyzwaniem dla chemika analityka.
EN
A method was developed for the preparative separation of two alkaloids from the crude extract of the radix of Rauvolfia verticillata (Lour.) Baill. in a single run. The two-phase solvent system composed of petroleum ether–ethyl acetate–methanol–water (5:5:2:8, v/v), where triethylamine (40 mmol/L) was added to the upper organic phase as the stationary phase and hydrochloric acid (10 mmol/L) was added to the lower aqueous phase as the mobile phase, was selected for this separation by pH-zone-refining counter-current chromatography (PZRCCC). For the preparative separation, the apparatus was rotated at a speed 850 rpm, while the mobile phase was pumped into the column at 2 mL/min. As a result, 112 mg of reserpine and 21 mg of yohimbine were obtained from 3 g of crude extract in a single run. The analysis of the isolated compounds was determined by high-performance liquid chromatography (HPLC) at 230 nm with purities of over 91.0%, and the chemical identification was carried out by the data of electrospray ionization–mass spectrometry (ESI–MS) and nuclear magnetic resonance (NMR) spectroscopy. The technique introduced in this paper is an efficient method for preparative separation of reserpine and yohimbine from devil pepper radix. It will be beneficial to utilize medicinal materials and also useful for the separation, purification, and pharmacological study of Chinese herbal ingredients.
EN
A high-performance liquid chromatography—diode-array detection method was developed and validated to determine simultaneously eleven major alkaloids in Corydalis decumbens (Thunb.) Pers. The alkaloids detected were corlumidine, protopine, coptisine, tetrahydrojatrorrhizine, palmatine, berberine, sanguinarine, papaverine hydrochloride, tetrahydropalmatine, bicuculline, and corydaline. Chromatographic separation was achieved using a C-18 column with a mobile phase composed of A (0.2% acetic acid solution, adjusted with triethylamine to pH 5.0) and B (acetonitrile), with stepwise gradient elution. Ultraviolet diode-array detection was used; chromatograms were examined at the wavelength of 280 nm. The regression equations showed a good linear relationship between the peak area of each marker and concentration (r = 0.9994–0.9999). The recovery values ranged between 93.66% and 100.54%. The method was fully validated with respect to detection and quantification limits, precision, reproducibility, and accuracy. The described high-performance liquid chromatography (HPLC) method was successfully used for the differentiation and quantification of the eleven major alkaloids in C. decumbens (Thunb.) Pers. and can be considered an effective procedure for the analyses of this important class of natural compounds.
EN
We present a new simple thin-layer chromatographic method designed for determination of the main alkaloids of Chelidonium majus L. In this study, we used roots and herb of the plant collected in spring and autumn. The alkaloid fractions were prepared according to modified pharmacopeial procedure [1]. In our method, we performed two-step elution onto silica gel plates. The first eluent consisted of chloroform, methanol, and water mixed with 70:30:4 proportion. The second eluent comprised of toluene, ethyl acetate, and methanol with 83:15:2 proportion. The described thin-layer chromatography (TLC) system allows qualitative and quantitative determination of the following alkaloids: sanguinarine, chelerythrine, chelidonine, coptisine, and berberine. For determination of protopine, eluent with n-buthanol, acetic acid, and water in 15:1.5:4 proportion was investigated.The dominant alkaloids observed in studied fractions were coptisine (1027.096 ± 13.367–287.474 ± 3.069 mg/100 g dry matter ± sdv) and chelidonine (1780.667 ± 263.522– 115.929 ± 14.694 mg/100 g dry matter ± sdv). The alkaloid detected in the least amount was chelerythrine (30.74 ± 7.526–1.143 ± 0.0651 mg/100 g dry matter ± sdv). The highest total amount of all alkaloids was determined in the fractions obtained from herbs in spring, and the lowest amount was detected in herbs autumn.Additionally, we compared amounts of studied alkaloids in different parts of plants (aerial parts and roots). The plants were collected in spring and autumn. Authors concluded that the presented method can be used as a valuable tool for screening studies on C. majus L.
8
Content available remote Modelowanie procesu adsorpcji boldyny na mezoporowatej krzemionce PHTS
PL
Przedstawiono zastosowanie mezoporowatej krzemionki PHTS w procesie adsorpcji boldyny. Dokonano matematycznego opisu adsorpcji modelowymi równaniami izoterm Langmuira, Freundlicha, Dubinina i Raduszkiewicza oraz Dubinina i Astachowa. Parametry izoterm oszacowano, wykorzystując dopasowanie nieliniowe oraz metodę regresji liniowej. W przypadku regresji nieliniowej stosowano metodę sumy znormalizowanych błędów jako kryterium optymalizacji wartości parametrów izoterm. Przeprowadzone badania wykazały, że model adsorpcji Langmuira, którego parametry oszacowano metodą regresji nieliniowej, najlepiej opisuje proces adsorpcji alkaloidu na badanym sorbencie.
EN
Boldine was adsorbed from Me2CHOH and MeCN solns. on plugged hexagonal templated SiO2 at 25°C to det. the adsorption isotherms analyzed then by using the Langmuir, Freundlich, Dubinin-Radushkevich and Dubinin-Astakhov models. To det. the isotherm parameters both linear regression and non-linear fitting anal. were used. The equil. adsorption data were best fitted by the Langmuir equation when the non-linear regression was used.
EN
A simple method for separation of matrine and oxymatrine from Sophora flavescens was developed with cation exchange resin coupled with macroporous resin. Based on the adsorption characteristics of matrine and oxymatrine, 001×732 cation exchange resin was used to absorb target alkaloids for removing most of the foreign matter, while BS-65 macroporous resin was chosen to purify these alkaloids. The result showed that the equilibrium adsorption data of matrine and oxymatrine on 001×732 resin and BS-65 resin at 30°C was fitted to Langmuir isotherm and Freundlich isotherm, respectively. The contents of matrine and oxymatrine were increased from 0.73% and 2.2% in the crude extract of the root of Sophora flavescens to 67.2% and 66.8% in the final eluent products with the recoveries of 90.3% and 86.9%, respectively.
PL
Przestrzenna konfiguracja na atomie azotu w cyklicznych β-aminoketonach powoduje, że związki te mogą występować w dwóch stereoizomerycznych formach, w których podstawniki na tym atomie mogą przyjmować orientację aksjalną lub ekwatorialną w stosunku do pierścienia piperydonu. Stereochemia N-podstawionych bicyklicznych β-aminoketonów była badana za pomocą metod eksperymentalnych i teoretycznych, m.in.: spektroskopia NMR, spektroskopii mikrofalowa, rentgenografii strukturalnej i obliczeń DFT.
EN
Because of pyramidal configuration of the nitrogen atom, tropanes, granatanes, and their derivatives can exist in two stereoisomeric forms, in which N-substituents can be oriented axial or equatorial with respect to the piperidone ring. The N-invertomer stereochemistry of N-substituted bicyclic β-amino ketones has been investigated using experimental, and theoretical methods, such as NMR, microwave spectroscopy, crystallography, and DFT calculations.
EN
A high-performance liquid chromatography (HPLC) method has been developed for simultaneous determination of six alkaloids, i.e., (−)-(R)-platydesmin, noroxyhydrastinine, berberine, skimmianine, canthin-6-one, and pteleine in the herbal medicine of Phellodendron amurense Rupr. The optimal condition for extraction and separation was achieved with a linear mobile phase gradient prepared from 0.1% phosphoric acid and acetonitrile. The LODs and LOQs for the analytes ranged from 0.06 to 0.22 μg mL-1 and from 0.25 to 0.80 μg mL-1, respectively. The optimized method was applied to the determination of alkaloids in P. amurense Rupr. and was found to be efficient. This method can provide a scientific and technical platform to the manufacturers for setting up a quality control standard as well as to the public for quality and safety assurance of the proprietary traditional Chinese medicines.
EN
Galanthamine, used as a drug for the treatment of Alzheimer’s disease and lycorine possessing important biological properties, are widely distributed alkaloids in the members of Amaryllidaceae family. In the present study, the contents of these alkaloids have been quantitatively determined by high-performance liquid chromatography (HPLC) coupled with diode array detector (DAD) in the aerial parts and bulbs of Galanthus woronowii Losinsk. collected from different localities in Northeastern Turkey. A simple extraction method utilizing columns pre-packed with diatomaceous earth (Extrelut®) was used. Chromatographic separation was achieved using an isocratic system with a mobile phase of trifluoroacetic acid-water-acetonitrile (0.01:90:10) applied at a flow rate of 1 mL min. -1. Validation studies were also carried out to show that the method is specific, accurate, and precise. In the tested specimens, the lycorine content ranged between 0.008 and 0.364% whereas the galanthamine content was found to be between 0.003 and 0.506%.
EN
Harmaline and harmine accounted for more than 70% in composition in extracts of P. harmala. More attention, however, should be paid to the other alkaloids which would be favorable or unfavorable to the efficacy and safety of the products. It was necessary to determine these trace alkaloids in the extracts; thereafter, most of them have been characterized. Diglycoside vasicine, vasicine, vasicinone, harmalol, harmol, tetrahydroharmine, 8-hydroxy-harmine, ruine, harmaline, and harmine were separated and identified with reference substances and characteristic MS spectra in extracts by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and high-performance liquid chromatography (HPLC). Three trace alkaloids, vasicine, harmalol, and harmol were determined using the developed chromatographic separation method subsequently. The average contents of vasicine, harmalol, and harmol in extracts of ten batches were 2.53 ± 0.73, 0.54 ± 0.19, and 0.077 ± 0.03%, respectively. The total content of the three alkaloids was 3.23 ± 0.90% (from 1.81 to 4.48%). For rough estimation of all the relative alkaloids except of harmaline and harmine, the average total areas of all peaks in extracts varied from 4.35 to 26.64% detected at 220, 254, 265, 280, and 380 nm, respectively. The results indicated that area normalization method was powerless for the quality evaluation for traditional herb medicine consisting of numerous compounds with highly differential features. It might be concluded that LC-MS or HPLC could be utilized as a qualitative and quantitative analytical method for quality control of the extracts from seeds of P. harmala L.
15
Content available remote Application of hydrophilic interaction chromatography in phytochemical analysis
EN
Hydrophilic interaction chromatography (HILIC) is a liquid chromatography technique when a polar stationary phases - silica or polar bonded phases and aqueous mobile phase containing amount of a less polar solvent (often acetonitrile) is applied. HILIC is important for the separation of highly polar substances including biologically active compounds, such as drugs, amino acids, peptides, proteins, nucleosides, neurotransmitters, etc. HILIC is also the appropriate method for analysis of plant extract polar components such as carbohydrates, amino acids, peptides, phenolic acids, flavonoids and some alkaloids. Plant extracts are usually multicomponent mixtures of compounds of wide polarity range, which often cannot be analyzed by use of a single separation and detection method because of the high chemical diversity. Good results are obtained by use of coupled method, e.g., reversed-phase liquid chromatography (RP-LC) and HILIC mode separation. The elution order in HILIC is usually opposite to that in RP separations. This orthogonality determines one of the advantages of HILIC - the possibility of creating multidimensional separations. An important feature of HILIC is the improved sensitivity with electrospray mass spectrometry. This is significant for the analysis of components existing in small concentration in multicomponent mixtures. The high acetonitrile content also gives additional advantage of HILIC - faster separations due to the lower viscosity of HILIC eluents compared to standard RP ones. The presented review deals with the optimization of HILIC separations and application of the method for analysis of plant extracts components.
EN
Chemometric characteristic of several alkaloids of various groups was performed by the relationships of their retention coefficients Re against mpdifier concentration in eluent. Retention of alkaloids was investigated on silica layers using nonaqueous eluents containing different amounts of methanol in dichloromethane or using aqueous eluents (in pseudo-reversed phases) using methanol or acetonitrile as modifiers and 2% of glacial acetic acid. For poorly separated compounds in such systems alumina or magnesium silicate (Florisil) and dichloromethane — methanol mixtures as eluents were used. Selectivity of separation was analyzed by correlation diagramsRM Al vs RMSi and RM (Florisil for data obtained in nonaqueous systems. Presented results as RF vs C % plots or RM(12) diagrams permit to choose selective systems for the separation of particular groups of substances and enable identification and chemometric characterization of investigated alkaloids.
PL
Charakterystyka chemometryczna wielu alkaloidów z różnych grup była przeprowadzona poprzez zależności ich współczynników retencji RF od stężenia modyfikatora w eluencie. Badano retencje, alkaloidów na cienkich warstwach żelu krzemionkowego stosując eluenty niewodne zawierające różne ilości metanolu w dichlorometanie lub przy użyciu eluentów wodnych (układy pseudoodwrócone) przy użyciu metanolu lub acetonitrylu jako modyfikatorów z dodatkiem 2% lodowatego kwasu octowego. Dla słabo rozdzielonych związków w powyższych układach zastosowano układy z tlenkiem glinu lub krzemianem magnezu (Florisil) i mieszaniny dichlorometanu z metanolem jako eluenty. Selektywność rozdzielenia była analizowana grupowo poprzez diagramy korelacyjne RM1 vs RMSI oraz RM si vs RM(Florisil) dla danych uzyskanych w układach bezwodnych. Przedstawione wyniki jako krzywe zależności Rf vs C% lub diagramy korelacyjne RM1 vs RM12 dają możliwość znalezienia selektywnego układu dla rozdziału poszczególnych grup substancji i umożliwiają identyfikacje, i chemometryczną charakterystykę badanych alkaloidów.
17
Content available remote Wspomnienia o profesorze Jerzym Suszce i szkic jego dokonań naukowych
EN
A quarter of a century has already passed since the most distinguished Polish pioneer in both natural products chemistry and stereochemistry, scientist meritorious for chemistry education, Professor Jerzy Suszko, passed away. He was born in Silesia near Teschen in 1889 and studied at the Polytechnic of Prague where he finished his PhD thesis under the auspices of Paul Rabe at the age of 24. After World War I he took on research work at the Jagielloński University in Cracow collaborating with Karol Dziewoński at the beginning. Next, after passing a habilitation examination and spending three years at the Univerity of Lvov, he moved to Poznań, where he spent the second half of his life, working as a professor and the Head of the Organic Chemistry Department of the University of Poznań. Furthermore, he was to become the Head of the Laboratory of Alkaloids of the Institute of Organic Chemistry of the Polish Academy of Sciences. He also held some highly responsible and a Dean of the Mathematical and Natural Science Faculty for a few years. The main scientific achievements of Professor Jerzy Suszko were concerned with the chemistry of physiologically active natural products and with the spatial structure of organic molecules. From among the natural products, the alkaloids and especially those of cinchona bark were the most intensively studied mainly because of their pharmacological properties. His synthetic and structural studies analysed all the most reactive and stereochemically important fragments of the molecules of quinine and related alkaloids. This resulted analogues differing by the kind of substituent in the quinoline moiety as well as the corresponding stereoisomers. Further significant achievements in the same field comprised, among others, the elaboration of a convenient method of a reverse conversion of quinotoxine (the product of an acid treatment of quinine but also occurring as the key intermediate in the quinine synthesis) and related toxins to the natural cinchona alkaloids, the determination of the pattern of rearrangement within the vicinal amino-alcohol fragment, and the discoveries in the chemistry of derivatives with a modified vinyl side chain, especially those being intramolecular ethers. The structure and conversion studies of other alkaloids concerned those occurring in the genera Papaver (codeine and rheadine), Lupinus and Cortinarius. At the beginning of the thirties, J. Suszko, proposed a new method of determining the molecular symmetry, especially in the case of fused-ring polycyclic aromatic hydrocarbons. This method was next verified mainly on naphthalene molecules and was based on the binding of two identical chiral substituents to the ring system in different positions followed by an analysis of the resulting stereochemical mixture. Other stereochemical studies concerning stereocontrolled syntheses, conformation stability and configuration determination were carried out on various cyclic apliphatic hydrocarbons, including bornane derivatives. Professor Jerzy Suszko educated a great number of graduated students both in chemistry and pharmacy. From about forty people who got their PhD degrees under his scientific supervision many later reached the highest levels in their scientific careers. He was a founding member of the Polish Chemical Society and was very much engaged in its activities during his whole life. He served in some responsible offices therein, including the President of the Society. He was also a member of several foreign scientific societies, including the American Chemical Society.
PL
Wykonano oznaczenie całkowitej zawartości alkaloidów w tytoniu papierosowym. Zanalizowano 14 gatunków papierosów produkcji polskiej. Alkaloidy z próbek tytoniu wydzielano ekstrakcyjnie mieszaniną toluen/chloroform (9:1 v/v) z roztworu silnie alkalicznego. Oznaczenie wykonano metodą miareczkowania konduktometrycznego w roztworze lodowatego kwasu octowego. Całkowita zawartość alkaloidów w przeliczeniu na nikotynę wynosiła 12-23 mg/papieros (1,7-3,8% nikotyny w tytoniu), błąd względny < +_4%. Wyniki oznaczeń były wyższe od otrzymanych metodą spektrofotometryczną.
EN
Total alkaloids in cigarette tabacco were determined. The analysis was made for 14 brands of cigarettes (made in Poland). The tabacco samples were isolated by extraction with a mixture toluene/chloroform (9:1 v/v) from a strongly alkaline solution. Determination was made by conductometric titration in glacial acetic acid solution. Total amounts of alkaloids (as nicotine) were 12-23 mg per cigarette (1,7-3,8% of nicotine in tabacco), relative error <+_4%. The results of determination were higher than obtained by spectrophotometric method.
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