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Chemical Ionization (CI) GC/MS Analysis of Underivatized Amphetamines Followed by Chiral Derivatization to Identify d and l-Isomers with Ion Trap Mass SpectrometryTarver, John A. (John Arthur) 05 1900 (has links)
An efficient two step procedure has been developed using CI GC/MS for analyzing amphetamines and related compounds. The first step allows the analysis of underivatized amphetamines with the necessary sensitivity and specificity to give spectral identification, including differentiation between methamphetamine and phentermine. The second step involves preparing a chiral derivative of the extract to identify d and 1-isomeric composition.
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Biologická aktivita obsahových látek rostlin XXVIII. Alkaloidy vybraných odrůd taxonu Narcissus cyclamineus REDOUTÉ a jejich účinek na acetylcholinesterasu a butyrylcholinesterasu. / Biological activity of plant metabolites XXVIII. Alkaloids from selected cultivars of Narcissus cyclamineus REDOUTÉ and their influence on acetylcholinesterase and butyrylcholinesteraseJanura, Michal January 2015 (has links)
Biological activity of plant metabolites XXVIII. Alkaloids from selected cultivars of Narcissus cyclamineus REDOUTÉ and their influence on acetylcholinesterase and butyrylcholinesterase. JANURA M.: Diploma work, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2015, Czech Republic. Abstract: The summary extracts of alkaloids from bulbs of N. cyclamineus esp. N. cyclamineus cv. Jenny, N. cyclamineus cv. Little Witch, N. cyclamineus cv. Rapture, N. cyclamineus cv. Surfside, N. cyclamineus cv. Peeping Tom, N. cyclamineus cv. Warbeld and N. cyclamineus cv. Skater's Waltz were obtained by the procedures common for this type of compounds. The alkaloid extracts were analyzed by GC/MS and the probable occurrence of individual alkaloid substances was observed. These extracts were also assayed for HuAChE and HuBuChE inhibitory activity. N. cyclamineus cv. Surfside with IC50 = 61,26 ± 6,42 µg/ml and N. cyclamineus cv. Warbeld with IC50 = 85,43 ± 11,13 µg/ml have the best results in inhibition of HuBuChE. The best inhibitory activity on HuAChE has N. cyclamineus cv. Warbeld with IC50 (HuAChE) = 36,82 ± 4,50 µg/ml. Key words: Narcissus, Acetylcholinesterase, Butyrylcholinesterase, GC/MS, Alzheimer's disease.
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Biologická aktivita obsahových látek rostlin XXIX. Alkaloidy vybraných odrůd taxonu Narcissus triandrus L. a jejich účinek na acetylcholinesterasu a butyrylcholinesterasu / Biological activity of plant metabolites XXIX. Alkaloids from selected cultivars of Narcissus triandrus L. and their influence on acetylcholinesterase and butyrylcholinesteraseFarkašovský, Marek January 2015 (has links)
Farkašovský M.: Biological activity of plant metabolites XXIX. Alkaloids of selected cultivars of Narcissus triandrus L. and their influence on acetylcholinesterase and butyrylcholinesterase. Diploma thesis. Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of pharmaceutical botany and ecology, Hradec Králové 2015, 70 pages Screening of seven bulb samples of Narcissus genus was performed. It included cultivars Narcissus triandrus cv. Hawera, Narcissus triandrus cv. Ice Wings, Narcissus triandrus cv. Stint, Narcissus triandrus cv. Tresamble, Narcissus cyclamineus cv. February Gold, Narcissus cyclamineus cv. Greenlet and Narcissus cyclamineus cv. Itzim. Primary extract was prepared by boiling crushed bulbs in ethanol 95% and then it was condensated. After extraction in diethyl ether and ethyl acetate was pure alkaloid extract dried with air flow in water bath. Isolated alkaloid extracts were tested for their inhibition activity on acetylcholinesterase and butyrylcholinesterase. Also GC-MS analysis was provided to identify alkaloids. These alkaloids were identified with GC-MS analysis - epinorgalanthamine, galanthamine, galanthine, haemanthamine, hippeastrine, homolycorine, cherylline, incartine, lycoramine, lycoramine-acetate, lycorine, narwedine, neruscine, sanguinine...
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Διερεύνηση της παρουσίας πετρελαιοειδών στον Πατραϊκό Κόλπο / Diffused pollution from dissolved/dispersed petroleum hydrocarbons in Gulf of PatrasΔεμπονέρα, Ευφροσύνη 07 April 2011 (has links)
Ο Πατραϊκός Κόλπος βρίσκεται στη Δυτική Ελλάδα μεταξύ Στερεάς Ελλάδας και Πελοποννήσου. Είναι ένας σχετικά αβαθής θαλάσσιος κόλπος που συνδέει το βαθύ Κορινθιακό Κόλπο με το Ιόνιο Πέλαγος. Η περιοχή μελέτης εκτείνεται από την παραλία της Καλόγριας, Δ. Λαρισσού, μέχρι το Ακταίο του Δήμου Ρίου. Πραγματοποιηθήκαν 2 εποχικές δειγματοληψίες, για τη συλλογή θαλάσσιου νερού, μια χειμερινή το Μάρτιο του 2009 και μία θερινή το Σεπτέμβριο του ίδιου έτους. Εμβόλιμα έγινε δειγματοληψία λίγο μετά από ατύχημα πετρελαιοκηλίδας στο λιμάνι της Πάτρας.
Στην εργασία αυτή με μία τροποποίηση της μεθόδου MARPOLMON-P, μετρήθηκε η εκπομπή φθορισμού των δειγμάτων μετά από την εκχύλιση τους με εξάνιο και διερευνήθηκε η παρουσία και η συγκέντρωση πετρελαϊκών ενώσεων καθώς και η διασπορά των πετρελαιοειδών στις παράκτιες περιοχές του Πατραϊκού Κόλπου. Σε κάθε δείγμα μετρήθηκαν φυσικές παράμετροι όπως η θερμοκρασία, το pH, η ηλεκτρική αγωγιμότητα και η θολερότητα του θαλάσσιου νερού. Η σύσταση των δειγμάτων της δεύτερης δειγματοληψίας διερευνήθηκε με τη χρήση GC-MS για τον εντοπισμό της πηγής των πετρελαϊκών ρύπων.
Τα αποτελέσματα των δύο κύριων δειγματοληψιών παρουσίασαν μεγάλες διακυμάνσεις στη συγκέντρωση αλλά και στην κατανομή των πετρελαϊκών υδρογονανθράκων, με τα εύρη των τιμών των συγκεντρώσεων να κυμαίνονται για τη χειμερινή από 0 – 290 μg/L ισοδύναμων μονάδων χρυσενίου (Λιμάνι Προβλήτα Αγ. Νικολάου) και για τη θερινή δειγματοληψία από 0- 56 μg/L μονάδων χρυσενίου (Μαρίνα Τερψιθέας). Η κατανομή και η διασπορά των πετρελαιοειδών φαίνεται να επηρεάζεται άμεσα από τη διεύθυνση και ταχύτητα των κυμάτων και του επικρατούντος άνεμου στις περιοχές δειγματοληψίας, αλλά και από την ωκεανογραφική συμπεριφορά του Πατραϊκού Κόλπου.
Στην ανάλυση GC/MS βρέθηκε μεγάλη αναλογία αλκάνιων σε όλα τα δείγματα, ενώ σε κάποια από αυτά βρέθηκαν πολυκυκλικοί αρωματικοί υδρογονάνθρακες και αλκένια, παράγωγα του πετρελαίου και των καυσίμων. Άλλες οργανικές ενώσεις όπως φθαλικοί εστέρες, σουλφίδια, αλκοόλες κ.α., ανιχνεύτηκαν σε χαμηλές συνήθως συγκεντρώσεις και πιθανόν προέρχονται από ρυπογόνες χερσαίες πηγές (επιφανειακή απορροή, αστικά και βιομηχανικά λύματα κ.α.). / The Gulf of Patras located between Continental Greece and Peloponnesus, in West Greece. The Gulf of Patras is relatively shallow and connects the deep Gulf of Corinth with Ionian Open Sea. The experimental area of our study extends from the beach of Kalogria, department of Municipality of Larissos, to Aktaion, department of Municipality of Rion. Two samplings, one in March of 2009 and one in September of the same year, were carried out in order to get sea water samples. After the occurrence of an oil slick accident in the port of Patras, an interstitial sampling was carried out.
In this study, MARPOLMON-P method partially modified was used, in order to estimate the fluorescence emission of the hexane extracted sea water samples. The presence of Dissolved/Dispersed petroleum hydrocarbons (DDPH) was also investigated as well as their concentration and the distribution of those in the maritime areas of the Gulf of Patras. In every sample, physical parameters such as temperature, pH, electrical conductivity and turbidity of sea water were estimated.
The identification of various substances within the samples of the second sampling (September of 2009) was conducted with GC-MS method, in order to find out the source of oil pollution.
Considering our results of the two main samplings we found out that there were important ranges in concentration as well as in distribution of DDPH. At first sampling the range of values was between 0 to 290 μg/L of chrysene equivalents (Port of St. Nikolaos) and at second sampling was between 0 to 56 μg/L of chrysene equivalents (Port of Marina Terpsithea). The results showed that wave’s direction and speed, wind speed and oceanographical status of Gulf of Patras affected by the distribution and dispersion of petroleum hydrocarbons.
During the GC/MS analysis high content of alkanes in all collected samples was identified, while some of them contained polycyclic aromatic hydrocarbons and alkenes, such as products of crude oil and mineral fuel. Other organic compounds such as pthallic esters, sulphides, alcoholes etc were found in low concentrations. These organic compounds were probably derived from pollutant ground sources (superficial rain flow or dilution drainage, urban and manufacturing wastesreams).
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Alkaloidy rodu Narcissus a jejich biologická aktivita / Alkaloids of the genus Narcissus and their biological aktivityTanková, Sabina January 2019 (has links)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy Candidate: Sabina Tanková Supervisor: PharmDr. Daniela Hulcová, PhD. Title of diploma thesis: Alkaloids of the genus Narcissus and their biological activity. Key worlds: Narcissus pseudonarcissus L. cv. Dutch Master, Amaryllidaceae, alkaloids, AChE, BuChE, POP, GSK-3β, biological activity. Alkaloid extract obtained from bulbs of Narcissus pseudonarcissus L. cv. Dutch Master was extracted by ethanol and was purified by liquid-liquid extraction and fractionated by column chromatography to individual fractions. At the end, were obtained 11 pooled fractions, which were used to isolate pure alkaloids. The ND 3-5 / 7 fraction was processed by preparative thin layer chromatography followed by crystallization of pure substances. In total, 5 alkaloid substances of ST1D2, ST1D3, ST2A, ST2B1 and ST3C were obtained from this fraction in various amounts. These substances were determined by GC-MS analysis, NMR analysis and optical rotation. Subsequently, the obtained data were compared with the NIST library spectra and the literature. Isolated substances have been identified as caranine, O-ethyllycorenine, narwedine, pluviine and N-demethylhomolycorine. The alkaloids obtained in sufficient amounts were subsequently subjected to...
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Alkaloidy čeledi Amaryllidaceae a jejich biologická aktivita I. / Alkaloids of the family Amaryllidaceae and their biological aktivity I.Puskásová, Dominika January 2019 (has links)
Puskásová Dominika: Alkaloids of the Amaryllidaceae family and their biological activity I. Diploma thesis 2019. Charles university in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy. The aim of this thesis was to isolate alkaloids from herbal extract, which was obtained from Narcissus pseudonarcissus 'Dutch Master' plant. The preparation and column chromatography of the extract were performed by PharmDr. Daniela Hulcová, Ph.D. as a part of her doctoral study. Using the preparative TLC method, 2 alkaloids marked as No.2.1 and 2.2.2 were isolated from the fraction No.4. Their structure was determined by using the NMR, GC-MS analysis and optical rotation. After comparing the data obtained with literature, the compounds were identified as (+)-homolycorine and (+)-masonine. Both homolycorine and masonine were subsequently subject to testing of inhibitory activity against acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), prolyloligopeptidase (POP) and glycogensynthase kinase 3β (GSK-3β). The activity was expressed as IC50 and was compared to IC50 of the reference substances. Galanthamine (IC50 AChE = 1,7 ± 0,1 μM, IC50 BuChE = 42,3 ± 1,3 μM) and huperzine A (IC50 AChE = 0,033 ± 0,001 μM, IC50 BuChE > 500 μM) were used as standards to compare the inhibitory activity...
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Alkaloidy čeledi Amaryllidaceae a jejich biologická aktivita II. / Alkaloids of the family Amaryllidaceae and their biological aktivity II.Kosturko, Štefan January 2020 (has links)
Charles University, Faculty of Pharmacy in Hradec Králové Department: Department of Pharmacognosy (16-16180) Author: Štefan Kosturko Supervisor: PharmDr. Marcela Šafratová, Ph.D. Advisor: PharmDr. Daniela Hulcová, Ph.D. Thesis title: Alkaloids of the family Amaryllidaceae and their biological activity II. Key words: Narcissus pseudonarcissus dutch master; bulbs; alkaloidal extracts; GC/MS analysis; biological activity; acetylcholinesterase; butyrylcholinesterase. The main aim of the thesis ‚,Alkaloids of the family Amaryllidaceae and their biological activity II.'' was the isolation of alkaloids, as a pure substances, in sufficient quantities to identify their structure and to test their biological aktivity in vitro. Alkaloids were separated from subfraction number 82 - 97 of weigh 2,3268 g. This subfraction was a part of the total plant extract, which was prepared by PharmDr. Daniela Hulcová Ph.D., as a part of her dissertation thesis and who also performed primary extraction and separation work. A total and concentrated alkaloid extract weighing 58 g, which included the aforementioned subfraction, was obtained. The already mentioned alkaloid subfraction, was divided by preparative thin-layer chromatography into five separates, which were subjected to further phytochemical work, and five pure...
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Actions of lignocellulolytic enzymes on Abies grandis(grand fir) wood for application in biofuel productionCherdchim, Banyat 27 October 2010 (has links)
No description available.
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