Bulletin of the Chemists and Technologists of Bosnia and Herzegovina

 

 

 

 

Issue 50

 

 

 

 

Publication date: June 2018

Full version of Bulletin

 

Table of contents

HPLC method for determination the content of thymol and carvacrol in Thyme tincture Original Scientific Article

Dedić Mirza, Bečić Ervina, Imamović Belma, Žiga Nermina, Medanhodžić-Vuk Saira, Šober Miroslav

Abstract: Genus Thymus contains about 300-400 species, many of which are used in traditional medicine. Thymus vulgaris (thyme) is the most commonly used Thymus. In official medicine, thyme is used as a general medicine for colds, flu, fever, coughing and bronchitis, such as: an antiseptic, spasmolytic, antifungicide, antitus, tonic, antihelmintic, antioxidant agent, antivirantic agent, carminative, sedative, diaforetic, antibacterial and as refresh remedy. The pharmacological effects of thyme are most closely related to its polyphenolic components, thymol and carvacrol. The most used chromatographic methods for determination of active compounds in herbal preparation is high-performance liquid chromatography. Results obtained by statistical processing are in the reference interval, which is  recommended by the ICH guidelines. By analyzing Thymi tincturae, it was found that the concentration of thymols was 0.807 mg/g of tincture, while the concentration of carvacrol was 0.082 mg/g tincture. This analysis is very fast, reliable and economical.

The method does not require a complicated sample preparation and as such can be used in the regular control of the content of thymol and carvacrol in the finished product and the semi-product (tincture).

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 50, 1-6.

Full text PDF

The effects of a context-rich approach in teaching thermodynamics Original Scientific Paper

Mahmutović Sabaheta, Mešić Vanes

Abstract: Earlier research shows that at all educational levels students have many misconceptions about thermal phenomena. Often these misconceptions are related to difficulties with differentiating the meaning that concepts have in everyday language and in the language of science. In this study we aimed to investigate the effects of enriching traditional instruction about thermodynamics with qualitative and quantitative examples from everyday life. To that end we conducted a pre-post quasi-experiment with 114 high-school students (mostly 15-year-olds) divided into four subgroups. Two subgroups (n=60) received the traditional instruction, whereas in the remaining two subgroups (n=54) a context-rich approach to learning thermodynamics has been implemented. Analysis of covariance showed that there are no statistically significant between-group differences when it comes to conceptual understanding of thermodynamics. However, the context-rich approach proved to be significantly more effective when it comes to increasing students' interest in science. The level of aroused interest was higher in girls than in boys.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 50, 7-12.

Full text PDF

Hemoglobin HbA1c and glucose blood levels in diabetic patients Original Scientific Paper 

Tahirović Ismet, Mahovac Enesa, Dizdar Muamer, Toromanović Jasmin, Mahmutović Omer, Lepara Zahid, Ajanović Atifa

 
Abstract: Diabetes mellitus (DM) is defined as an absolute or relative lack of insulin, or a state of chronic hyperglycemia. Hemoglobin A1c (HbA1c) is a minor Hb form, produced in vivo by post-translational glycosylation. In the last 30 years, in biochemical laboratory practice, HbA1c became a "gold standard" for clinical monitoring of DM. The aim of this study was to determine the glucose and HbA1c levels in DM suffering patients at “Zavidovići” Health Center in different time periods,and estimate glucoregulation. The levels of HbA1c and glucose were measured in 100 patients with 3-month time period. The results were analyzed by appropriate statistical methods, to determine whether there are statistically significant differences between the two measurements. A spectrophotometric method was used to determine the level of HbA1c, whileglucose was determined using an enzymatic-colorimetric method on biochemical analyzer. It was found that in 61 of the total number of subjects, the levels of HbA1c and glucose were significantly reduced (p***<0.001) three months after the first measurement, which leads to the conclusion that their glucoregulation  have improved. In the remaining 39 subjects the levels of HbA1c and glucose were significantly increased (p*<0.05) in the same time period, which leads to the conclusion that their glucoregulation worsened.
 
Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 50, 13-18.

Full text PDF

Effect of solvents on phenolic compounds extraction and antioxidant activity of Prunus spinosa L. fruits Original Scientific Paper

Tahirović Azra, Bašić Neđad, Čopra-Janićijević Amira

Abstract: The aim of this work was quantification of phenolic compounds and determination of antioxidant activity of Prunus spinosa fruit extracts. Extractions of phenolic compounds were carried out with water and four alcohol mixture (50% methanol, 50% ethanol, 80% methanol, and 80% ethanol). Spectrophotometric determination of phenolic compounds was done by Folin-Ciocalteu method and flavonoids with AlCl3 method. Arnow reagent was used in determination of phenolic acid content while anthocyanin content was determined with pH differential method. Butanol-HCl assay was applied to determine proanthocyanidin content. Investigated phenolic compounds were in the range of 14.02-30.20 mg GAE/g dw (total phenolic compounds), 0.789-1.538 mf RE/g dw and 0.450-1.039 mg QE/g dw (flavonoids), 4.55-7.24 mg CAE/g dw (phenolic acids), 0.361-1.05 mg CGE/g dw (anthocyanins), 3.97-26.49 mg CE/g dw (proanthocyanins). The highest content of investigated compounds was found for 50% ethanol extract (except anthocyanins) and the lowest content was in water extract. The highest antioxidant activity had 50% ethanol extract for all antioxidant methods. Very high correlations were found between antioxidant activity and content of all analyzed compounds. 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 50, 19-24.

Full text PDF

Gender differences in understanding of thermal expansion Original Scientific Paper

Vidak Andrej

Abstract: Investigation of gender differences in science allows us to tailor our instruction to the needs, interests and abilities of all our students. In this study we aimed to investigate gender differences in conceptual understanding of thermal expansion. To that end tenconceptual questions were administered to 195 first year students at the Faculty of Chemical Engineering and Technology, University of Zagreb. Male students significantly outperformed female students. Particularly large differences in favor of males were observed on questions that required reasoning about thermal expansion in one dimension.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 50, 25-30.

Full text PDF

Influence of the delta ferrite content on the corrosion behavior of austenitic stainless steel Nitronic 60 Original Scientific Paper

Gigović-Gekić Almaida, Bikić Farzet, Avdušinović Hasan

Abstract: Nitronic 60 (UNS S21800) is a highly alloyed austenitic stainless steel with increased content of manganese and silicon. It has a good mechanical and corrosion properties at elevated temperatures and loads. Nitronic 60 has the austenitic microstructure at room temperature but depending on chemical composition the presence of other phase in austenite matrix is possible, i.e. delta ferrite. The aim of this study is better understanding of delta ferrite content influence on corrosion sensitivity of Nitronic 60. The corrosion sensitivity test was conducted in the corrosion cell using potentiostat/galvanostat according to Standard ASTM G5 (Princeton Applied Research, model 263A-2, with the PowerCORR® software), (Standard, ASTM G5-94). Investigation was performed in 0.9% NaCl solution. Taffel extrapolation method was used to test general corrosion. Method of cyclic polarization was used for investigation of pitting corrosion. Tests were performed at room temperature, 20±1°C.The corrosion tests results indicate that the intensity of both examined forms of corrosion, general and pitting corrosion, is increased with increasing delta ferrite content.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 50, 31-34.

Full text PDF

Correlation between hemoglobin A1c and lipid profile in Bosnian diabetic patients - gender differences Original Scientific Paper

Mandal Šaćira, Čaušević Adlija 

Abstract: The prevalence of Type 2 diabetes mellitus (T2D) as a metabolic disease is rapidly rising worldwide. The purpose of this study was to determine concentrations of hemoglobin A1c (HbA1c), fasting glucose, and lipid profile in a total of 104 adults, 24 patients with newly diagnosed Type 2 diabetes (40-60 years of the age), 40 Type 2 diabetes, and 40 healthy subjects as control group (the same ages). On the basis of these results, we were able to assess the differences due to gender and age in tested population as well as the relationship between glycemic control (HbA1c) and serum lipid profile. Therefore, we properly evaluated the importance of HbA1c as an indicator of dyslipidemia in patients with T2D in selected Bosnian population. Hemoglobin A1c was determined by immunoturbidimetric assay, while fasting glucose and lipid profile were analyzed according to standard clinical methods on BT PLUS 2000-Biotechnic Instruments Bioanalyzer. We found that glycated hemoglobin concentrations in newly diabetic subjects were higher than those in other two groups. Statistically significant differences between study populations were seen at the level of glucose, cholesterol, HDL and LDL cholesterol, HbA1c, triacylglycerol and patient age. Also, our results have shown the significant negative correlation between HbA1c and cholesterol and HDL levels (p***<0.001) while positive correlation was observed with glucose and patient age (p***<0.001) in all study groups. According to our results, hemoglobin A1c can also be used as a predictor of dyslipidemia and thus early diagnosis of dyslipidemia can be used as a preventive measure for the development of cardiovascular diseases in patients with Type 2 diabetes mellitus.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 50, 35-42.

Full text PDF

Chemical characterization, antimicrobial and antioxidant properties of Mentha spicata L. (Lamiaceae) essential oil Original Scientific Paper

Nikšić Haris, Durić Kemal, Omeragić Elma, Nikšić Hedija, Muratović Samija, Bečić Fahir

Abstract: The aim of the present study was to examine chemical composition, antibacterial and antioxidative activity of essential oil extracted from the leaf of Mentha spicata. The essential oil composition was investigated by GC/MS. Thirty three components were identified, accounting for 98,9% of the essential oil. Dominant components were carvone (56,4%), limonene (16,2%), 1,8 cineole  (7%), β-pinene (2,4) and α- terpinene (2,3%). Agar disk diffusion assay was used to evaluate antibacterial activity of essential oil. The essential oil exhibited significant level of antibacterial activity against all tested bacterial strains. In general, Gram-negative bacteria were more susceptible to M. spicata essential oil than Gram-positive bacteria. E coli was the most sensitive of the microorganisms to the antibacterial activity of M. spicata essential oil. The 2,2-diphenyl-l-1-phthydrazide (DPPH) radical removal method was used for evaluating the antioxidant potential of the essential oils.. The result showed a considerable level of antioxidant activities of the essential oil investigated with (IC50 = 41, 23 µg/mL).  Based on our results, M. spicata essential oil with a strong antioxidant and antibacterial activities, could serve as a safe natural antioxidant and antiseptic supplements in the pharmaceutical and food industry.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 50, 43-48.

Full text PDF

Determination of clindamycin hydrochloride content in 1% clindamycin lotion Original Scientific Paper

Dedić Mirza, Bečić Ervina, Imamović Belma, Žiga Nermina 

Abstract: Clindamycin is a broad spectrum antibiotic that belongs to the lincosamide group. It acts mostly as a bacteriostatic antibiotic, but it also has mild bactericidal activity. The most common clinical conditions in which they are used are: infections in gynecology, gingiva infections, respiratory tract, skin and soft tissue infections, intra-abdominal infections, pneumonia caused by Pneumocystis jiroveci, toxoplasmosis, malaria, babesiosis, and acne. Clindamycin is available in several pharmaceutical forms, which can be administered orally, intravenously, intramuscularly or intradermally. It is usually prepared as an ex tempore 1% clindamycin lotion that is used dermally, in the treatment of a mild form of acne. The proposed UV-Vis spectrophotometric method allows analyzing the content of clindamycin hydrochloride in the extemporaneous formulation of 1% clindamycin lotion. Clindamycin chloride content analysis was performed on samples of 1% clindamycin lotions purchased in pharmacies in Canton Sarajevo. The results showed that the content of clindamycin hydrochloride in the ex tempore prepared preparations varied from 21% to 142%.

The UV-Vis method does not require complicated preparation of the sample, and is therefore fast, reliable and economical, and as such can be used in regular control of the content of clindamycin hydrochloride inex tempore prepared lotion.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 50, 49-54.

Full text PDF

Application of Photochemistry Principles, Models, and Simulations in the Study of Gaseous Components of Space Bodies and Interstellar Matter with Recent Developments Review

Krečo Anes, Biščević Helena, Handžić Azra, Gojak-Salimović Sabina  

Abstract: Space exploration was from its inception multidisciplinary field of research. Whether it is a design of devices that separate light into it different wavelengths, comparison of extracted data to known characteristics of spectrum of molecules, engineering of complex autonomous system of interplanetary probes or intricate calculations of vehicle trajectories, the objective was the same, understanding of the Universe around us. Chemistry as fundamental natural science finds its place in the area known as astrochemistry. When it comes to direct experimentation most of work is done on board the remotely operated space probes that are often self-enclosed laboratories on other space objects or orbiters. However, data collected by these is overshadowed by sheer volume of information extracted from light collected by Earth and space-based observatories and it is here that photochemistry takes the prime role. In last few decades, with development of computing technology, mathematical models have taken root in interpreting data collected by observations and predicting the characteristics of objects analogous to already well-studied ones. Several of the recent studies in this field have been discussed in this paper.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 50, 55-60.

Full text PDF

 

 

 
 
 
 
 

 

 

 

 
 

  

 

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina

 

 

 

 

Issue 51

 

 

 

 

Publication date: December 2018

Full version of Bulletin

 

Table of contents


Synthesis, characterization and in vitro antimicrobial activity of the Cu(II) and Fe(III) complexes with 1-cyclopropyl-6-fluoro-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid Original Scientific Article

Horozić Emir, Cipurković Amira, Ademović, Zahida, Kolarević, Lamija., Bjelošević, Demir, Zukić, Amila, Hodžić, Snježana, Husejnagić, Daria, Ibišević, Merima

Abstract: 1-Cyclopropyl-6-fluoro-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid (Ciprofloxacin, CFL) is a drug that belongs to the second generation of fluoroquinolone antibiotics with a wide range of effects on Gram-positive and Gram-negative bacteria. The bactericidal action of ciprofloxacin results from the inhibition of the enzymes topoisomerase II (DNA gyrase) and topoisomerase IV. In organism there is a possibility of interaction of CFL with biogenic elements in the blood, which could lead to the formation of complexes. This can cause change in the activity of antibiotics towards pathogenic microorganisms. The aim of this work was to investigate the interaction of CFL as ligand with the biological cations Cu(II) and Fe(III) in physiological condition. Synthesized complexes were characterized using IR spectroscopy and stereo-microscopy. Antimicrobial screening was performed on bacterial strains of Escherichia coli, Enterococcus faecalis, Staphylococcus aureus and Salmonella Enteritidis. The results of IR spectroscopy showed that the Cu(II) and Fe(III) complexes with CFL were formed through the oxygen donor atoms of carboxyl and carbonyl group of the ligand. The color and size changes of the crystal of the ligand and complexes were also clearly seen. Antimicrobial screening has shown that CFL and CFL complexes have similar antimicrobial activity against all tested strains. The Cu(CFL)2 complex showed better antimicrobial activity compared to the Fe(CFL)2(H2O)2 complex.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 51, 1-6.

Full text PDF

Influence of tested parameters on biodiesel quality obtained from used and unused vegetable oil Original Scientific Paper

Nuhanović MIrza, Memić Semir, Sušić Edita, Smječanin Narcisa

Abstract: The aim of this study was to obtain biodiesel, synthesized by transesterification from used (waste) and unused (industrial) sunflower vegetable oil, purify with following solvents: distilled water, 4% H3PO4 and 4% HCl, determine biodiesel quality parameters, and finally analyze the influence of the selected parameters and used solvents for purification on the content of soap in biodiesel. Rinsing of biodiesel for each used solvent was carried out 2, 3, 5, 7 and 9 times with a certain amount of above-mentioned solvents. Differences in the values of selected parameters (indicators) of biodiesel quality as well as the concentration of soap in the purified biodiesel between single rinses for the used solvents were observed, and the values of the examined parameters between different purifiers with the same rinse number were compared. In this study, the estimated effects of washing methods on biodiesel density, kinematic viscosity, acid number, peroxide number, flash point, and biodiesel synthesis yield were determined. It was found that there were no significant changes and deviations of the obtained values of the examined parameters, when purifying biodiesel with different solvents (for both type of used oils), except for the value of the peroxide number for acid washing. Based on the results obtained in this work, acid solution is better for soap removal.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 51, 7-12.

Full text PDF

Synthesis and biological evaluation of xanthen-1,8-dione derivatives Original Scientific Paper

Veljović Elma, Špirtović-Halilović Selma, Muratović Samija, Osmanović Amar, Novaković Irena, Trifunović Snežana, Završnik Davorka

Abstract: Fourteen previously synthesized 3,3,6,6-tetramethyl-9-aryl-3,4,5,6,7,9-hexahydro-1H-xanthen-1,8(2H)-dione derivatives were evaluated in vitro for their antimicrobial, antiproliferative and antioxidant activity. Also, in this work 3,3,6,6-tetramethyl-9-(4-acetamidophenyl)-3,4,5,6,7,9-hexahydro-1H-xanthen-1,8(2H)-dione (15) was synthesized according to the same procedure and structure was confirmed by IR, NMR spectroscopy and mass spectrometry. Compounds were screened against Gram negative bacterium Pseudomonas aeruginosa and Gram positive bacteria Staphylococcus aureus and Bacillus subtilis. The antifungal activity of synthetized xanthene compounds was tested against fungus Saccharomyces cerevisiae. The cell lines HeLa, SW620, HEpG2, A549 and3T3 were targets for antiproliferative effects of synthesized compounds. The results showed that the most potent, as antimicrobial and antiproliferative agent, was compound with two atoms of bromine substituted on aryl ring, and the most potent antioxidant agent was compound 3,3,6,6-tetramethyl-9-(2-methoxy-3-hydroxy-4-nitrophenyl)-3,4,5,6,7,9-hexahydro-1H-xanthen-1,8(2H)-dione with IC50 of 0.045 mM and 70.41% of inhibition DPPH.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 51, 13-18.

Full text PDF

The use of chemistry learning materials within the pre-learning strategy: findings from a teachers' survey Original Scientific Paper

Smerdel Snježana, Zejnilagić-Hajrić Meliha

Abstract: The pre-learning strategy includes activities oriented at students’ preparation prior to the class. Using such activities increases the pre-knowledge level which allows linking new information with the existing knowledge more efficiently and consequently reduces working memory overload. Research results indicate frequent use of various learning materials within the frame of the pre-learning strategy. The main purpose of this research is to determine the frequency of chemistry learning materials (CLMs) use within the frame of the pre-learning strategy in Croatian secondary schools. The quantitative descriptive survey research was conducted on a sample consisting of 77 high-school chemistry teachers and 62 vocational school chemistry teachers from all regions in Croatia. Data were collected through an online questionnaire and processed with descriptive and inferential statistics. According to the obtained results, it is most common that teachers use their own materials (Word, PowerPoint) and text/image chemistry learning materials for students’ preparation prior to the chemistry class. Audio-materials (podcasts), audiovisual materials (screencasts) and digital materials are represented insufficiently. The frequency of use of chemistry learning materials does not differ between high-school and vocational school chemistry teachers’.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 51, 19-23.

Full text PDF

Atmospheric Corrosion of Metals in Urban Area Original Scientific Paper

Burović Selma, Korać Fehim, Huremović Jasna, Ostojić Jelena

Abstract:  Atmospheric corrosion rate depends on the content of the individual components in atmosphere, temperature of air,and  refers primarily on the moisture content, the content of the various particles and the SOx and NOx gases. Washing out the pollutants from the atmosphere creates strong acids, bases and salts that can corrode various metal and non – metallic structures. The analysis of certain precipitation parameters, analysis of metal and alloy samples exposed to the atmosphere in Sarajevo and Kiseljak, and analysis of metal and alloy samples without atmospheric influence were carried out. The methods used for sample analysis are linear voltammetry and cyclic voltammetry. An iron plate, chrome coated iron plate with worn out surface, zinc coated iron plate with worn out surface and brass plate were used as a samples. It was observed that the corrosion of samples in Sarajevo is more intensive as compared to the corrosion of samples tested in the area of Kiseljak. Linear voltammetry measurements in a given range of potentials gave more pronounced corrosion currents in the samples from urban area. Cyclic voltammetry measurements gave pronounced reduction peak at -0.25 V for brass, and for chrome coated iron plate at -0.05 V. For the zinc coated iron plate sample, potentials were shifted to negative values that are characteristics of   zinc pair. For chrome coated iron plate, reduction peak was detected at -0.75 V. The cyclic voltammogram for zinc coated iron plate with worn out surface is similar to the cyclic voltammogram for zinc coated iron plate. Urban area of Sarajevo is heavily polluted by different pollutants which can affect all aspects of life and environment. The occurrence of acid rains is intensified, which increases the corrosion of material of which the constructions are made.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 51, 25-33.

Physical Chemistry for Undergraduate Students: Sources of Students’ Difficulties and Potential Solution Original Scientific Paper

Gojak-Salimović Sabina, Korać Fehim, Zejnilagić-Hajrić Meliha, Nuić Ines 

Abstract:  Traditionally, university students struggle with physical chemistry courses at Faculty of Science. This is particularly evident in the mutual integration of knowledge in general chemistry, physics, and mathematics that are considered as fundamental to physical chemistry. This paper presents the results of research conducted with the 2nd year chemistry students at the Faculty of Science University of Sarajevo, with the main aim to find solutions to these difficulties that could lead to greater learning efficiency, and a successful continuation of their chemistry studies. The results indicated that students’ knowledge of concepts relevant to physical chemistry is not at a satisfactory level. This is in line with the rather low students’ grades in general chemistry, general physics and mathematics during the first year of the study. Students reported their most common difficulties: the lack of time for learning, the lack of literature recommended by the syllabus, and certain mathematical concepts they do not understand. To overcome them, it is important to direct students to use the available resources more efficiently, and to emphasize the significance of knowledge integration.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 51, 35-40.

Full text PDF

Hardness of the solder alloy Cu-In-Sb in dependence of the molar ratio of the components Original Scientific Paper

Aljilji Ajka, Sivac Anisa, Velić Sifet, Mahmutović Omer

Abstract:  An increasing concern for environmental protection led to the establishment of strict provisions regarding the use of alloys that could have a detrimental effect on the environment, which resulted in reduction of use lead solder materials. Copper-based alloys in particular represent a possible replacement for standard not-lead solder.  Alloys on the basis of copper, indium, and antimony are important in production of new solder materials. Thus, it is desirable the knowledge about different ratios of mentioned elements in these alloys, related to their influence on the mechanical properties of alloy, for the development of new high quality solder materials. In this paper, the hardness of ternary system Cu-In-Sb was investigated, for three vertical cross sections with molar ratio: Sb:Cu = 1, Cu:In =  1, Sb:In = 1. Highest hardness has been found with 0,30 mol fraction of copper in Cu-InSb  vertical cross section. Hardness continually decreases with the increas of molar percent of antimony. Indium has shown the least variation and influence on the hardness of these alloys. The most variation in hardness was during the change of the molar fraction of copper, which indicates that the copper is the most important element for the hardness of this system.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 51, 41-45.

Full text PDF

Characterization of raw materials and final product in the cement production Technical Paper

Đukić Duško, Lazić Dragica, Drljača Dijana, Imamović Mugdin

Abstract:  Cement is a hydraulic binder formed by the grinding process of cement clinker, as intermediate product, which is produced by baking the lime-clay raw material mixture to the sintering temperature. This research paper describes mineralogical analysis technique of primary raw materials, auxiliary components for cement production, by-product clinker  and final product, cement. Used technique is X-ray diffraction technique, which is one of the most modern instrumental techniques today. Obtained results are provided in the form of diffractogram, that is used to display the mineralogical phase of components. X-ray diffraction method confirmed the theoretical knowledge of the mineralogical components of tested raw materials, clinker and cement. As expected, the main component of limestone is mineral calcite, as active compound, fly ash and slag as amorphous substances and clinker contains clinker-minerals and gyspum contains calcium sulfate dihydrate in large percentage. Main components of cement are all minerals provided in clinker and raw materials. These experiments were carried out in the Holding Company Cement Plant in Lukavac, Bosnia and Herzegovina.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 51, 47-52.

Full text PDF

 

 
 
 
 

 

 

 

 
 

  

 

 

 

 

 

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina

 

 

Issue 52

 

 

 

Publication date: June 2019

Full version of Bulletin

 

Table of contents

Inhibition of Iron Corrosion in Seawater Using Rosemary Extracts (Rosmarinusofficinalis L.) Original Scientific Article

UDK: 620.193:669-032.26
 
Šćepanović Jelena, Korać Fehim, Gutić Sanjin, Ostojić Jelena, Herenda Safija, Bunjo Amira, Korać Selma

Abstract: Due to a growing awareness of environmental protection, an interest in replacing toxic corrosion inhibitors with more environmentally acceptable alternatives is also growing. Chromates, as one of the best inhibitors, have been eliminated as technically viable inhibitors because of their high toxicity, and the use of polyphosphates has diminished as they disrupt the balance in the Plantae kingdom. The emphasis is on exploration and testing of organic compounds that can be obtained from plant material. Rosemary extracts (leaf and flower) have been shown to have inhibitory activity on iron corrosion in 3% NaCl and seawater. Corrosion rate values ​​show that rosemary flower extracts are better inhibitors of corrosion than the leaf extracts and that the maximum inhibitory protection has not been achieved in the range of tested concentrations.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 52, 1-10.

Full text PDF

Curcumin: Phytochemical Therapy in the Treatment of Hyperlipidemia Review

UDK: 547.979:616-085
 
Pehlivanović Belma, Bečić Fahir

Abstract: In modern world, hyperlipidemia is the most common disorder mainly caused by lifestyle habits and the major cause of cardiovascular, coronary and atherosclerotic changes. Such disorder is characterized by abnormally elevated levels of any or all lipids or lipoproteins in the blood. A wide range of drugs are available for the treatment of hyperlipidemia, class of antihyperlipidemic drugs, but such drug-therapies are carried out with presence of various side effects. In the last decades, different in vitro and in vivo research have been conducted to confirm the therapeutic effects of various phytochemical agents that overcome the side effects caused by synthetic drugs. According to Ayurvedic recommendations and experimental studies, numerous phytochemical agents have been reported to possess different antihyperlipidemic properties. One of the most studied phytochemical agent - curcumin, herbal polyphenol and active ingredient which can be extracted from the powder rhizome of the plant Curcuma longa, has been reported to possess a wide range of pharmacological properties such as antimicrobial, antioxidative, antiinflammatory and anticancer property. Recent studies also suggests curcumin as potential lipid lowering candidate in treatment of hyperlipidemia. The aim of this review is to present and discuss phytochemistry, molecular mechanism of hypolipidemic activity of curcumin, demonstrating its importance as potential therapy for the treatment of hyperlipidemia.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 52, 11-16.

Full text PDF

Experimental and theoretical study of Aspartic acid Original Scientific Paper

UDK: 577.1:661.73.001.55

 

Movre Šapić Iva, Vidak Andrej, Dananić Vladimir

Abstract: The aim of this research is to detect zwittterionic structure of the aspartic acid and confirm the experimental spectra with quantum chemical calculations. The experimental IR and Raman spectra of aspartic acid powder show no vibrational bands of OH and NH stretching in expected spectral region. We assume that zwitterionic structure of aspartic acid is responsible for lowering the frequencies of these vibrations. An extensive experimental and computational research supports this assumption. Our DFT calculation strongly suggests the need for the dielectric environment in order to stabilize the zwitterionic structure of a single molecule. The network of intermolecular hydrogen bonding between aspartic acid molecules provides this dielectric environment. The DFT quantum mechanical calculations corroborate this assumption by optimizing a four-member group of molecules, which also gives an explanation of broad IR spectrum lines.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 52, 17-22.

Full text PDF

Investigation of Inhibitory Effect of the Aloe Vera Extract on Corrosion of Aluminium Alloys Original Scientific Paper

UDK: 620.193:546.6
 
Šćepanović Jelena, Herenda Safija, Radonjić Dragan, Vuksanović Darko

Abstract: This paper considers the inhibition effect of Aloe Vera on the selected aluminium alloys in 10 % sulfuric acid and 3 % sodium chloride solutions at room temperature, using methods of potentiodynamic polarisation and cyclic voltammetry. The study involved as-cast and heat-treated 2xxx alloys, with the scanning speed of 1mV/s for linear polarisation and 50 mV/s for cyclic voltammetry. The various constant potential was applied for each tested alloy. Polarisation results indicate that the transpassivation occurs in an acid medium in case of each alloy. The obtained results indicate that Aloe vera extract acts as a cathodic inhibitor.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 52, 23-32.

Full text PDF

 

 

 

 

 

 
 
 

 

 

 

 
 

  

 

 

 

 

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina

 

 

Issue 53

 

 

 

Publication date: December 2019

Full version of Bulletin

 

Table of contents

Protection of fuel filter with alkaline and acid zinc coatings Original Scientific Article

Šćepanović Jelena, Herenda Safija, Korać Fehim, Vuksanović Darko, Radonjić Dragan

DOI: 10.35666/ghtbh.2019.53.01
UDK: 541.1:620.197.6-034.5

 

Abstract: Galvanic coatings are applied so that the surface of the base material obtains appropriate properties, corrosion resistance, durability, aesthetic appearance, and long-term application in the appropriate industry. In this paper, the aim was to protect steel fuel filters with alkaline and acid zinc coatings of different thicknesses. The coating of zinc, which is applied from the alkaline electrolyte, provides good corrosion protection with excellent coating flexibility. The thickness of the coating by the X-ray fluorescence method was tested, followed by coating tests, corrosion resistance, and electrochemical tests. The results of adhesion showed a high quality coating, as no corrosion occurred during the test. The corrosion resistance tested by the salt chamber method speaks of the appearance of white and red corrosion. On alkaline electrolyte coatings, white corrosion occurred after 168 hours of exposure to the salt test, while on white zinc samples there was a white corrosion after 240 hours of exposure. Tafel polarization diagrams have been determined: corrosion potentials, current intensities, anode and cathode Tafel coefficients and calculated corrosion rates. The active and passive corrosion zone is determined by the cyclic voltammetry.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 53, 1-8.

Full text PDF

Calibration bath uncertainty in precision temperature measurements Original Scientific Article

Đekić Maja, Brkić Inasa, Hodžić Nedžadeta, Čohodarević Semir

DOI: 10.35666/ghtbh.2019.53.02
UDK: 541.11:53.08

 

Abstract: Calibration baths are widely used in many laboratories worldwide for the calibration of thermometers by comparison. They come in different shapes and sizes and use different media (water, alcohol, silicon oil etc.), but a certain nonuniformity of theused media is always present. During precision temperature measurements, uniformity (homogeneity and temporal stability) of a calibration bath is of the utmost importance since its contribution to total measurement uncertainty is the largest. The temperature gradient can be described as a change of temperature at different positions inside the bath working volume. Temporal temperature stability depends on many factors such as: the bath temperature, control system, bath construction and the flow of the used media inside the bath, just to name a few.  In this paper, we investigate uniformity of a cylindrical calibration bath. Homogeneity is determined by measurement of axial and radial temperature gradient inside the bath. Stability is examined by observation of the change in temperature reading during certain period of time. The obtained results are compared with manufacturer specification and can be used for determination of calibration bath contribution to total measurement uncertainty during calibration of thermometers.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 53, 9-13.

Full text PDF

Phenolics content and antioxidant activity of three Sorbus species Original Scientific Article

Tahirović Azra, Mehić Emina, Kjosevski Nina, Bašić Neđad

DOI: 10.35666/ghtbh.2019.53.03
UDK: 581.19:547.56

 

Abstract: The phenolic content and antioxidant activity of Sorbus aucuparia L., Sorbus aria (L.) Crantz and Sorbus austriaca (Beck) Hedlund leaves and fruit were investigated. The quantification of total phenolics, flavonoids and phenolic acids was performed using the Folin–Ciocalteu, Dowd and Arnow methods, respectively. The antioxidant activity of the extracts was evaluated using DPPH, TEAC and FRAP methods with Trolox as a standard. Leaves had a higher content of phenolic compounds and antioxidant activity than the fruits for all species. The highest content of phenolics (76.11 mg gallic acid equivalents (GAE)/g plant), flavonoids (15.86 mg rutin equivalents (RE)/g plant) and phenolic acids (44.54 mg caffeic acid equivalents (CAE)/g plant) was determined for S. austriaca leaves. Sorbus austriaca fruit had the highest content of phenolics (13.21 mg GAE/g plant), flavonoids (1.82 mg RE/g plant) and S. aucuparia fruit had the highest content of phenolic acids (9.05 mg CAE/g plant). The antioxidant activity was in the range: DPPH=38.42–274.52 μmol Trolox equivalents (TE)/g plant; TEAC=43.23–403.02 μmol TE/g plant; FRAP=47.13–706.96 μmol TE/g plant. The highest values of antioxidant activity were found for S. austriaca leaf and fruit extracts while the lowest values were determined for S. aucuparia leaves and S. aria fruit. The antioxidant activity was highly correlated with total phenolics and phenolic acids.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 53, 15-21.

Full text PDF

Toxic compounds in homemade spirits in Bosnia and Herzegovina: A pilot study Original Scientific Article

Marjanovic Aleksandra, Omeragic Elma, Djedjibegovic Jasmina, Turalic Amila, Lugusic Aida, Caklovica Faruk, Sober Miroslav

DOI: 10.35666/ghtbh.2019.53.04
UDK: 663.5:615.9 (497.6.)

 

Abstract: The main aim of this preliminary study was to investigate the presence of potentially toxic compounds (methanol, hydrocyanic acid and urea) in homemade fruit spirits produced in different parts of Bosnia and Herzegovina. A total of 15 samples of 8 different fruit spirits were analyzed (apple, apricot, cherry, grape, pear, plum, quince and juniper). Content of hydrocyanic acid was higher than maximum permissible level in 5 out of 15 samples. In general, the average content of methanol was higher in samples from Bosnia comparing to the samples from Herzegovina (874.62 vs. 563.99 g/hL of pure alcohol), but still was lower than maximum concentration proposed by national regulation (1200 g/hLof pure alcohol for fruit spirits and 1000 g/hL of pure alcohol for grape spirit) except for one grape spirit sample (1162.2 g/hL of pure alcohol). Urea was detected in all analyzed samples (5.819 to 77.82 mg/L) with the average concentration of 37.95 mg/L. Since this is, to our knowledge, the firststudy that included the chemical analysis of homemade spirits in BiH, these results are of great importance for the further research.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 53, 23-27.

Full text PDF

Changes in mineral content in trainees’ blood and urine due to high-intensity training Original Scientific Article

Hajdo Diana, Memić Mustafa, Domitrović Robert, Šabanović Elma

DOI: 10.35666/ghtbh.2019.53.05
UDK: 612.126:796.015

 

Abstract: High-intensity training is becoming more popular nowadays when people have less time to engage in prolonged physical activity. Expertly led high intensity training is a safe way to achieve desired fitness goals. The aim of the study was to check if there were significant changes in the concentrations of sodium, potassium, calcium, magnesium, zinc, iron and copper in the blood and urine of twelve trainees after a short but intense training. Blood and urine sampling was performed before and after high intensity training where bodyweight exercises and exercises with external load were used. Statistical analysis was performed using paired t-test (2-tailed) with α=0.05 as statistical significance. The results obtained showed that the measured mineral concentrations varied as a result of intense physical activity, but these variations were small and did not have a general trend of increase or decrease of analyzed mineral content. Based on these results, it can be concluded that, from the standpoint of the mineral concentrations loss, short high-intensity training is safe for the trainee’s health.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 53, 29-35.

Full text PDF

Determination of water content in infant formula Original Scientific Article

Jurković Josip, Sulejmanović Jasmina, Tahmaz Jasmina, Gavrić Teofil

DOI: 10.35666/ghtbh.2019.53.06
UDK: 543.3:641.562-053.31

 

Abstract: Water is one of the most important constituents of food, very important to be accurately quantified. Furthermore, water content affects the stability and shelf life of food. The evaluation of most chemical parameters is based on dry mass and many methods use heating which result in losing all volatile compounds, including water. Also, it is much harder to extract all of water if we have a complex matrix. Regarding this, the aim of this study was to determine water content in different infant formula by various methods. For examination of water content in three different types of infant formula three different techniques were used (oven sample processor, drying oven and halogen drying) and compared to classical Karl Fischer titration with two different solvents. Each sample was measured in ten probes, and classical Karl Fischer titration was used as a reference.  The results showed that the reference method was the best regarding speed of measurement, amount of sample needed and obtained water contents (3.01- 4.35%), followed by Karl Fischer in boiling methanol (2.80-4.30), oven sample processor (2.96-4.23%), halogen drying (2.74-4.03%) and drying oven (2.38-3.52). Methods using heating could not remove all water from the sample within a reasonable time.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 53, 37-42.

Full text PDF

 

 

 

 

 

 
 
 

 

 

 

 
Page 5 of 11

     

Bulletin of the Chemists and Technologists of B&H
Zmaja od Bosne 35, Novo Sarajevo, B&H
Phone: +387-33-279-904; +387-33-279-902