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Bulletin of the Chemists and Technologists of Bosnia and Herzegovina
Issue 43
Publication date: December 2014 |
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Table of contents
Determination of Caffeine in Different Comercialy Available Green and Black Teas Original Scientific Article
Salihović Mirsada, Šapčanin Aida, Pazalja Mirha, Alispahić Amra, Dedić Alema, Ramić Emina
Abstract: Methyl derivatives of xanthine are a group of alkaloids commonly used for their effects as mild stimulants on various organ systems such as cardiovascular and central nervous system (CNS), respiratory system and skeletal muscles. The naturally occurring methyl xanthines are caffeine, theophylline and theobromine. The aim of this study was to determine content of caffeine in the green and black tea commercially available from Bosnianmarketsby simple, fast and economical methods. The simultaneous quantitative and qualitative determination was based on spectrophotometric UV/Vis method and thin layer chromatography (TLC) method. Content of caffeine in the green tea was in the range 33.90 to 110.73(mg/g), and in the black tea was in the range from 10.32 to 63.00 (mg/g). The highest content of caffeine was detected in the green tea of Slovenian manufacturer, and in the black tea of Croatian manufacture. Consuming a large amount of these types of tea could cause some health problems.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 43, 1-4.
Spectrophotometric determination of binding constants of Ru(III) salicylideneimine complexes with CT DNA Original Scientific Article
Ljubijankić Sead, Zahirović Adnan, Memišević Mahira, Ljubijankić Nevzeta, Kahrović Emira
Abstract: The interactions of Ru(III) complexes with Schiff bases derived from salicylaldehyde and aminophenol, butylamine and naphthylamine with general formula Na[Ru(N-R-5-X-salim)2] (R = C6H4O, X = H, Cl, Br, NO2), Na[RuCl2(N-R-5-X-salim)2] (R = C4H9, X = H, Cl, Br, NO2) and [Ru(N-R-5-X-salim)3] (R = C10H7, X = H, Cl, Br) with CT DNA, were investigated by spectroscopic titration. Experimental data show that Ru(III) complexes with salicylideneimine bind CT DNA with constants of 104 M-1. The results indicate the influence of 5-X-substituents on Kb values.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 43, 5-10.
Acetylcholinesterase and butyrylcholinesterase inhibitory activity of extracts from medicinal plants Original Scientific Article
Talić Stanislava, Dragičević Ivan, Ćorajević Lejla, Martinović Bevanda Anita
Abstract: Inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), enzymes which breakdown acetylcholine and butyrylcholine, are considered as a promising strategy for the treatment of Alzheimer’s disease(AD). A potential source of AChE and BuChE inhibitors is provided by the abundance of plants in nature. In the present study, we selected five plants used in traditional medicine to treat different disorders of the central nervous system.Aqueous and methanolic extracts of sage (Salvia officinalis L.), arnica (Arnica montana L.),rue (Ruta graveolens L.), St. John'swort(Hypericum perforatumL.)and aronia (Aroniamelanocarpa(Michx.) Elliot.)were tested for the AChE and BuChE inhibitory activity using Ellman’s colorimetric method. Galanthamine hydrobromide was used as positive control. The results show that extracts from the aeiral parts of St John's wort and rue and flowers of arnica could inhibit the activity of AChE or BuChE or both. The best inhibition effect was observed using the water extract of rue, then methanolic extracts of arnicaand StJohn'swort at concentration of 400 μg ml-1.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 43, 11-14.
Synthesis, Caracterization and Interaction with CT DNA of Novel Cationic Complex Ru(III) with Indazole and Schiff Base Derived from 5-Chlorosalicylaldehyde Original Scientific Article
Begić-Hairlahović Sabina, Kahrović Emira, Turkušić Emir
Abstract: Novel cationic complex compound of Ru(III) with indazole and Schiff base derived from 5-chlorosalicylaldehyde and aniline has been synthesized. Formulation and characterization of the complex was performed using CHN analysis, MALDI-TOF/TOF mass spectrometry, FT-IR spectroscopy and UV/Visible spectrophotometry. In the octahedral environment of Ru(III), coordination of bidentate Schiff bases occurs through azomethine nitrogen and deprotonated phenolic oxygen while in indazole via nitrogen atom. The interaction of the complex with CT DNA (calf thymus DNA) was carried out under physiological conditions using spectrophotometric titration.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 43, 15-20.
Kinetics and mechanism of diazepam release from solid dispersions Original Scientific Article
Hadžiabdić Jasmina, Elezović Alisa, Rahić Ognjenka, Vranić Edina
Abstract: According to the biopharmaceutics classification system, diazepam belongs to the class II drugs. Inadequate dissolution rate of diazepam can be the limiting factor for its absorption rate. The aim of the present study was preparation of diazepam solid dispersions using various carriers like polyethylene glycol 2000, polyethylene glycol 4000 and polyvinylpyrrolidone K30, estimation of solubility and dissolution rate of prepared diazepam solid dispersions and comparison of these data to that of pure diazepam. The solid dispersions were prepared by solvent evaporation method. Phosphate buffer pH 6.8 was used as dissolution medium. Solid dispersions of diazepam with polymers resulted in increased solubility and dissolution rate of diazepam (highest with polyvinylpyrrolidone K30). The rate release kinetics of diazepam from the solid dispersions followed Hixson-Crowell cube root law. The correlation coefficient (r2) values of the Hixson-Crowell’s cube root model were slightly higher (0.9665 to 0.9977) when compared to the zero and first order release model. The high values of regression coefficients suggested that all formulations followed Korsmeyer-Peppas model of release kinetics. The low values of the release exponent (< 0.45) indicated that the mechanism of diazepam release from all the formulations could be described as a Fickian diffusion mechanism.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 43, 21-28.
Seasonal Variation in Content and Chemical Composition of Essential Oils from Leaves of Mentha longifolia Huds. (Lamiaceae) Original Scientific Article
Nikšić Haris, Kovač-Bešović Elvira, Durić Kemal, Korać Nermina, Omeragić Elma, Muratović Samija
Abstract: The aim of the present study was to appraise variation in content and the chemical composition of essential oil from the leaves of Mentha longifolia as affected by harvesting season. Quantities of the essential oils were determined according to the European Pharmacopoeia 4th Ed. and chemical profiles by using a gas chromatography – mass spectrometry. The highest content of the essential oil was found plant during the flowering stage (1.9%). The main constituents of the essential oil through all the three phenophases were oxygened monoterpenes piperitone oxide (1.9-63.6%) and 1,8-cineole (5-12%), and sesquiterpenes trans-caryophyllene (3-9.3%) and germacrene D (0.16-10%). In general, the composition of the essential oil in all the three investigated phenophases was generally similar with quantitative differences. Oxygenated monoterpenes were dominant during flowering stage and after flowering stage, followed by sesquiterpene hydrocarbons. Presence of β-ocimene, γ-terpinene, and carvone were noticed only before flowering; cederole, β-cubebene and α-caryophyllene during the flowering stage; and 3-carene after flowering. Analysis of the qualitative and quantitative composition of main constituents of the essential oil in all the three investigated phenophases led to the conclusion that the piperitone oxide, as the major compound could be used as the stable chemotype marker for the taxonomy of Mentha longifolia.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 43, 29-34.
SPE extraction and TLC identification of tetracycline and fluoroquinone in surface water Original Scientific Article
Bečić Elvira, Imamović Belma, Dedić Mirza, Šober Miroslav
Abstract: Simultaneous identification of the antibiotics tetracycline, oxytetracycline, chlortetracycline, ciprofloxacin and enrofloxacin in surface water is reported. The method is based on solid-phase extraction (SPE), separation and identification by thin-layer chromatography (TLC). TLC separation was performed on TLC silica gel 60 F254 plates using a mobile phase system water/methanol/dichloromethane (6/35/59) (v/v). The plates were previously impregnated with 10% solution EDTA pH 9,0 and dried in a horizontal position for at least two hours at room temperature and then in an oven at 105°C 30 minutes shortly before use. Antibiotics were extracted on the OASIS HLB 6cc/500 mg cartridges. Aliquots of 10 μl of the water sample and reference solutions were applied to the plate. After development the plates were air dried and the chromatograms were visualized under UV light at λ = 254 nm and λ = 366 nm. Proposed method can be applied for screening of investigated antibiotics in water samples were antibiotic concentration is equal or higher than 5 μg/ml.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 43, 35-40.
Electrochemical characterization of (1E)-1-N-{[4-(4-{[(E)-N-(3-aminophenyl) carboxyimidoyl] phenoxy} butoxy) phenyl] methilidene} benzene -1,3-diamine Original Scientific Article
Šter Anamarija, Balić Tomislav, Marković Berislav, Medvidović-Kosanović Martina
Abstract: Oxido-reduction properties of a newly synthesized Schiff base were investigated by cyclic voltammetry and differential pulse voltammetry. Measurements were conducted in a three electrode voltammetric cell in a non-aqueous media. Glassy carbon was used as a working electrode, platinum wire as counter electrode and non-aqueous Ag/Ag+ electrode as a reference electrode. Inert atmosphere was acomplished by system purging with high purity argon Ar 5 (fAr = 99,999 %),before each measurement. Cyclyc voltammograms revealed one oxidation peak of the investigated Schiff base (Ep,a = 0.69 V), which increased with increasing concentration (c = 3.1 ·10-5 mol dm-3... 1.25 ·10-4 mol dm-3) and scan rate (ν = 50...300 mV/s). Differential pulse voltammetry showed one oxidation peak Ep,a = 0,69 V, which also increased with increasing concentration.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 43, 41-44.
Kinetin Induced Changes in Rutin content in Knautia sarajevensis (G. Beck) Szabó Shoot Cultures Original scientific article
Karalija Erna, Kurtagić Harun, Parić Adisa
Abstract: Knautia sarajevensis, Dipsacaceae, is an endemic species found at wood margins and meadows only on mountains of Dinaric Alps. Members of this family are widely used in traditional medicine as rich sources of pharmacologically important substances. Since it is well known that flavonoid compounds are one of the main carriers of biological activities of plant extracts, the aim of this study was to investigate cytokinin effects in concentration changes of flavonoid constituents. Four different flavonoid constituents were analysed: quercetin, naringenin, hesperetin and rutin in extracts of K. sarajevenis shoots cultivated on three in vitro treatments (control, 1.0 mg L-1 kinetin and 10.0 mg L-1 kinetin). All extracts were prepared using dried material and 80% methanol HPLC grade. Analysis of rutin indicated that high cytokinin concentrations did induce improvement of rutin content, but these concentrations are still lower than those recorded for control treatment. Further analysis using different types and concentrations of cytokinins are necessary to establish a pattern of cytokinin induced concentration changes in content of these four investigated flavonoids in Knautia sarajevensis.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 43, 45-48.
Knowledge of Atomic Structure and Visualization: A Research Results from Questionnairewith First-year Chemistry Students Original scientific article
Hadžibegović Zalkida, Salibašić Džana, Galijašević Semira
Abstract: This research study was conducted in order to assess the students’ knowledge and ideas about basic concepts in both general chemistry and general physics courses. The research topic was the atomic structure knowledge and visual models of the atom that students already have. Research examined how students’ knowledge of scientific atomic theory has progressed during study year using a questionnaire as pretestand posttest. The study results showed that students’ knowledge about atoms atomic structure has predominantly descriptive and simplified character. Students have had their alternative visions of atomic structure based on their knowledge about Rutherford or Bohr model of the atom instead of the current scientific model of the atoms. That was a case even when they successfully completed the atomic structure questionnaire. Only 5% of the first-year chemistry students under this study showed an expected scientific literacy level related to the atomic theory topics after two semesters of study general chemistry and general physics. We propose different learning sequences to exceed this problem in order to help the freshmen to be prepared adequately for further more complex study. This approach is very important for the students’ development of abstract thinking that is necessary for the complete scientific literacy.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 43, 49-56.
DTF Study and Biological Activity of Some Methylxanthines Short Communication
Salihović Mirsada, Huseinović Šukrija, Špirtović-Halilović Selma, Osmanović Amar, Dedić Alema, Ašimović Zilha, Završnik Davorka
Abstract: Using quantum chemical methods (density functional theory level), biologically active methylxanthines were investigated. All calculations were performed at B3LYP/6-31G* level of theory. The electronic chemical potential, highest occupied molecular orbital (HOMO)/lowest unoccupied molecular orbital (LUMO) gap, dipole moment, vibration frequencies, electrophilicity, chemical hardness and logP were calculated. Obtained results correspond well with some of the pharmacological properties. Calculated properties could be useful for quantitative structure-activity relationship (QSAR) analysis which will be performed in the future.
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 43, 57-60.
