Bulletin of the Chemists and Technologists of Bosnia and Herzegovina

 

 

Issue 54

 

 

 

Publication date: June 2020

Full version of Bulletin

 

Table of contents


Phenolic Composition, Antioxidant and Antimicrobial Activity of Cotoneaster Medik. Species from Bosnia and Herzegovina Original Scientific Article

Mahmutović-Dizdarević Irma, Dizdar Muamer, Čulum Dušan, Vidic Danijela, Dahija Sabina, Jerković-Mujkić, Anesa, Bešta-Gajević Renata

DOI: 10.35666/ghtbh.2020.54.01

UDK: 577.115:616.379

Abstract: Although the genus Cotoneaster Medik. includes mainly ornamental species, there are some data regarding its biological activity. The purpose of this study was to analyze the content of phenolic compounds, acetylcholinesterase inhibition, antioxidant and antimicrobial activity of methanolic extracts of leaf and bark of C. integerrimus Medik., C. tomentosus (Aiton) Lindl. and C. horizontalis Decne. The C. tomentosus leaf extract exhibited the highest content of total phenols (135.86 mg GAE/g) and flavonoids (18.17 mgQE/g), and also the most potent antioxidant activity against nonbiogenic free radicals, while the highest inhibition of acetylcholinesterase had the leaf extract of C. horizontalis (IC50 0.34 mg/mL). All extracts showed a significant level of antibacterial and antifungal activity against tested microbial strains. The largest inhibition zones were observed against Candida albicans treated with C. integerrimus leaf extract (30.50±0.50 mm). Furthermore, C. integerrimus extract was the most effective in the majority of bacterial strains tested. The results indicated that methanolic extracts of the investigated Cotoneaster species have promising bioactive and therapeutic potentials.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 54, 1-6.

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Serum Iron Concentration and Lipid Profile in Type 2 Diabetes Patients Original Scientific Article

Mandal Šaćira

DOI: 10.35666/ghtbh.2020.54.02
UDK:531.19(497.6) 

Abstract: Recent studies have been showed important role of elevated iron levels in pathogenesis of Type 2 Diabetes mellitus (T2D) and insulin resistance. The aim of this study was to determine serum of free iron concentration in T2D patients and find out associations with lipid profile. The study included 51 participants (27 healthy control and 24 no treated diabetes patients), with ages from 45 to 65 45-65 ages and both gender. As expected, concentrations of serum iron were elevated in diabetic patients compare to healthy subjects while statistical significant difference were shown between iron levels in control group and group with good control of glycaemia (p<0.05). In addition, there was a significant positive correlation between free iron concentration and LDL cholesterol levels and negative significant correlation between iron concentrations with HDL cholesterol in diabetics (p<0.05). These findings suggest that increase serum of free iron concentrations may have an important role and influence in development of disease, especially in lipid metabolism and profile as well in risk of further complications of diabetes. 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 54, 7-12.

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Chromatographic Methods for the Determination of Primula Acid 1 Content in Primulae extractum fluidum Original Scientific Article

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

DOI: 10.35666/ghtbh.2020.54.03

UDK: 581.19:582.689.2

Abstract: Primula veris L. (Primulaceae)is healing plant, whose root is officially used to treat cough associated with cold. Other reported indications are respiratory, thoracic and mediastinal disorders. These effects are result of high contents of triterpenoid saponins and phenolic glycosides. Primula acid 1 (PA 1, also primulasaponin 1) is main active component in Primula elatior L. This paper presents an optimized high pressure liquid chromatography (HPLC) method for the determination of primula acid 1 content in Primulae extractum fluidum. TLC was performed to check for the presence of the substance of interest. The determination was performed by reversed phase chromatography using C18 as a stationary phase. The mobile phase used for separation consisted of 0.2% H3PO4 and acetonitrile. This method was validated through different parameters. The detection limit for primula acid 1 was LD=10.41 µg/ml, and the quantification limitwas LQ=34.69 µg/ml. In order to determine the content of primula acid 1, a calibration curve was constructed, and the content of primula acid 1 was calculated by the equation of the calibration curve and was 0.2793 mg per gram of extract. The results and simple preparation of sample show that HPLC is the method of choice for this type of analysis.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 54, 13-18.

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Phytochemical Investigation and Antioxidative Capacity of Triterpenes Present in Plant Species Belonging to Lamiaceae Family Original Scientific Article

Jordamović Nadir, Niksic Haris, Muratovic Samija, Gusic Irma, Koric Emina, Alagic Larisa, Pasic Maja, Duric Kemal

DOI: 10.35666/ghtbh.2020.54.04

UDK: 581.19:582.929.4

Abstract: Triterpenes are persistently associated with observed bioactivities of extracts obtained from plant material that contains these very important natural products. Many species belonging to Lamiaceae family have been used for the presence of essential oil and very little is known about the presence of the triterpene substances in this family. Qualitative and quantitative analyses of this very important substances, in the aerial parts of eight species, all belonging to Lamiaceae family, were investigated in this study. Different extracts containing triterpene substances were tested by DPPH method to evaluate their antioxidative capacity. TLC and HPLC methods, used for the analytical determination of triterpenes, showed the presence of betulin, betulinic acid, ursolic acid and oleanolic acid. Betulin (3.2 mg/g) and betulinic acid (37.1 mg/g) were the most abundant triterpene components in the hexane extracts of Rosmarinus officinalis L. Ursolic acid (0.14 mg/g) was the most abundant triterpene compound in the hexane extract of Thymus pulegioides L. All tested samples demonstrated DPPH scavenging activity in a concentration dependant manner, with a wide range of IC50 values from 0.4 mg/mL to 3.3 mg/mL.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 54, 19-26.

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Investigation of the Antioxidant Synergisms and Antagonisms among Caffeic, Ferulic and Rosmarinic Acids using the Briggs-Rauscher Reaction Method  Original Scientific Article

Gojak-Salimović Sabina, Ramić Sabrina

DOI: 10.35666/ghtbh.2020.54.05
UDK: 541.1:(547.587:66.097.8)

Abstract: Phenolic acids have been attracting huge attention over recent years due to their prominent antioxidant activity and potential health benefits. In this study, the antioxidant activity of caffeic, ferulic, and rosmarinic acids was evaluated using Briggs-Rauscher reaction method. In addition to single phenolic acids at different concentrations (50, 100, 200 and 250 µM), equimolar mixtures of two phenolic acids and all three phenolic acids were tested. The best ability to inhibit oscillations, i.e. the highest antioxidant activity showed rosmarinic acid at a concentration of 250 µM. Inhibition time of the Briggs-Rauscher oscillating reaction mixture was obtained experimentally for the different combinations of phenolic acids and compared with theoretical values calculated by adding up the effects of phenolic acids analyzed individually. The most of tested phenolic acids mixtures showed a difference in the antioxidant activity when compared to individual values of their constituents. The highest synergistic effect showed a mixture of caffeic acid and ferulic acid at a concentration of 250 µM while the highest antagonistic effect showed the mixture of caffeic acid, ferulic acid and rosmarinic acid at same concentration.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 54, 27-30.

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Gender differences in chemical engineering students identified in understanding of rolling motion Original Scientific Article

Vidak Andrej

DOI: 10.35666/ghtbh.2020.54.06
UDK: 371.315:54-057.875.1/.2(497.5)

 

Abstract: In this research papaer we presented the results of exploration of gender differences in conceptual understanding of rolling motion (velocities and work-energy principle). For this purpose, we have selected nine conceptual items and conducted experiment with 184 first year students at the Faculty of Chemical Engineering and Technology, University of Zagreb. Results show that male students significantly outperformed female students. We detected particularly large differences on items that tests knowledge of the rolling phenomena.  Results of our research can help teachers to create lessons that are adapted to general student population.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 54, 31-36.

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Modified QuEChERS extraction and GC-MS analysis of selected cannabinoids from human urine Original Scientific Article

Korać Nermina, Vidic Danijela, Sutlović Davorka

DOI: 10.35666/ghtbh.2020.54.07
UDK: 615.9:616.63

 

Abstract: The aim of this work is to apply a modified QuEChERS method to extract cannabinoids from urine, using a mixture of salts for extraction in an appropriate ratio instead of commercially available cartridges. The analysis was performed on blank urine to which a known concentration of tetrahydocannabinol (THC), cannabinol (CBN) and cannabidiol (CBD), 11-hydroxy-Δ9-tetrahydrocannabinol (THC-OH) and 11-nor-9-carboxy-Δ9-tetrahydrocannnabinol (THC-COOH) was added. Six solvents, as well as four solvent mixtures, were tested for extraction and the solvent mixture acetonitrile : dichloromethane (1:3) was selected for which the best recovery factor was obtained. Derivatization of all samples was done with MSTFA (N-trimethylsilyl-N-methyl trifluoroacetamide) + 1% TMCS (2,2,2-Trifluoro-N-methyl-N-(trimethylsilyl)-acetamide, chlorotrimethylsilane) at room temperature.

The prepared extracts were analyzed by a coupled system, gas chromatography-mass spectrometry (GC-MS) in full-scan mode. Peaks of selected cannabinoids are wellseparated indicating that there was no interference with the selected analytes. The results were calculated from a calibration curve ranging from LOQ to 1000 ng/mL for selected cannabinoids with a correlation factor over 0.998. The LOD and LOQ for THC are (3.0 ng/mL; 9.0 ng/mL), for CBN (5.0 ng/mL; 18.0 ng/mL) for CBD (5.0 ng/mL, 16.0 ng/mL), for THC-OH (2.6 ng/mL; 8.7 ng/mL) and for THC-COOH (5.0 ng/mL; 15.0 ng/mL). The recovery factor was recorded in the range of 79.40% for THC-COOH to 94.86% for CBN. 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 54, 37-44.

 

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Bulletin of the Chemists and Technologists of Bosnia and Herzegovina

 

 

Issue 55

 

 

 

Publication date: December 2020

Full version Bulletin

 

Table of contents


Study of uranium bioaccumulation capacity of Salvia officinalis L. and Ocimum basilicum L. enhanced by citric acid Original Scientific Article

Ibragić Saida, Smječanin Narcisa, Hodžić Sara, Ramčić Šadija, Nuhanović Mizra

DOI: https://doi.org/10.35666/ghtbh.2020.55.01

UDK: 544.58:623.459.86

Abstract: Plants possess various intrinsic mechanisms necessary to accumulate and either sequester or detoxify soil contaminants, including radionuclides. The aim of this study was to determine the bioconcentration factor of two fast growing plants Salvia offlicinalis L. (sage) and Ocimum basillicum L. (basil) that were cultivated in pH neutral soils artificially contaminated with three different concentrations of uranium (211, 352 and 470 mg/kg). The efficiency of citric acid was evaluated with respect to the enhancement of the phytoextraction process. The results showed that the bioconcentration factor did not differ significantly between the selected species (0.01 - 0.03). Citric acid was added in doses (50 mL, 30 mM) until the first effects of uranium phytotoxicity appeared. After four doses of citric acid, the bioconcentration factor reached 0.05 for both plants. The increase of uranium content taken up by the respective plants was more pronounced. Thus, the uranium content of sage grown in contaminated soil (470 mg/kg) increased from 6.03 to 21.28 mg/kg in citric acid-treated soil. The data obtained confirmed the efficiency of citric acid in enhancing phytoextraction of uranium and further suggest that even plants of a rather small biomass can be useful in phytoremediation given the appropriate treatment through induced phytoextraction with appropriate chemical agents.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 55, 1-6.

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Qualitative and quantitative determination of ligustilide as bioactive marker in apiaceous botanicals Original Scientific Article

Durić Kemal, Nikšić Haris, Muratović Samija, Gušić Irma, Korić Emina

DOI: https://doi.org/10.35666/ghtbh.2020.55.02
 
UDK:547:577.1]633.886 

Abstract: Variety of bioactivities has been associated with ligustilide present in root of Angelica sinensis, and predominantly used for the treatment of irregular menstrual cycles and premenstrual syndrome. Recent pharmacological studies showed that medicinal plants containing ligustilide, have anti-inflammatory effects and contribute to the improvement of  cognitive functions, alleviate brain damage, inhibit tumor necrosis factor of some cell lines, and have nephron-protective effects and neuroprotective activity. In this work, quantification of ligustilide using quantitative 1H NMR (qHNMR) in sealed tubes was performed. Four plant species were investigated: A. sinensis, Ligusticum porteri, Ligusticum striatum, andLigusticum sinense. Modified supercritical CO2 extraction of essential oil from root of four investigated species, was performed. qHNMR spectroscopy  showed following percentage of ligustilide: L. porteri essential oil 3.74 (%); L. sinense essential oil 1.16 (%); L. striatum essential oil 6.61 (%) and A. sinensis essential oil 14.56 (%). The highest percentage of oil was obtained from the root of L. porteri but the highest percentage of ligustilide was obtained from A. sinensis essential oil.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 55, 7-12.

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Synthesis and characterization of Fe(III) complex with thiosemicarbazide-based ligand Original Scientific Article

Ljubijankić Nevzeta, Galijašević Semira 

DOI: https//:doi.org/10.35666/ghtbh.2020.55.03

UDK: [546.72+547.576]:543.544.164
 

Abstract: Complex iron(III) salicylaldehyde thiosemicarbazone with a formula Na[Fe(STSC)2] have been synthesized. Ligand, salicylaldehyde thiosemicarbazone (SCT) was prepared through the condensation reaction of salycilaldehide with thiosemicarbazide. Na[Fe(STSC)2] has been synthesized by reacting FeCl3 with thiosemicarbazide based ligand bearing ONS donor atoms. Complex has been formulated and characterized by mass spectrometry, infrared and UV/visible spectroscopy. The facts showed the formation of a complex in metal:ligand stoichiometric ratio 1:2. The ligand is coordinated as an ONS tridentate dianion via oxygen atom after the deprotonation of the phenolic OH-group, azomethine nitrogen and sulphur in thiol form of the deprotonated thiosemicarbazide residue. Antioxidant activity was determined, where ligand showed significant activity, while complex, at low concentration, exhibited almost no activity.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 55, 13-18.

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Peroxidase activity of hemoglobin and heme destruction in the presence of hydrogen peroxide and CT-DNA Original Scientific Article

Galijašević Semira, Muhidinović Mona, Grizić Selma

DOI: https://doi.org/10.35666/ghtbh.2020.55.04

UDK: 577.1:547.963.4

Abstract: The aim of this study was to investigate the peroxidase activity of Hb with different concentrations of hydrogen peroxide and compare it with hypochlorous acid effect on Hb. Hypochlorous acid at higher concentrations decomposed Hb and heme, releasing fee iron ion from the metal center. High concentrations of hydrogen peroxide switched the peroxidase activity of Hb towards the partial Hb and heme destruction. Heme alone was degraded showing that the Hb conformation and protein environment protects Hb from the distraction in the presence of highly increased hydrogen peroxide concentration that occurs as a result of oxidative stress. In the presence of CT-DNA acted inhibition of the peroxidase activity of Hb was observed signaling inhibited hydrogen peroxide consumption.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 55, 19-24.

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Bulletin of the Chemists and Technologists of Bosnia and Herzegovina

 

 

Issue 56

 

 

 

Publication date: June 2021

 

Full version Bulletin

 

Table of contents



Determination of Sulfites in Fruit Juices and Meals for Infants and Toddlers Original Scientific Article

Marjanović, A., Đeđibegović, J., Lugušić, A., Šober, M.

 

DOI: 10.35666/2232-7266.2021.56.01

UDK: 615.9:663.81-053.3

Abstract: Plants possess various intrinsic mechanisms necessary to accumulate and either sequester or detoxify soil contaminants, including radionuclides. The aim of this study was to determine the bioconcentration factor of two fast growing plants Salvia offlicinalis L. (sage) and Ocimum basillicum L. (basil) that were cultivated in pH neutral soils artificially contaminated with three different concentrations of uranium (211, 352 and 470 mg/kg). The efficiency of citric acid was evaluated with respect to the enhancement of the phytoextraction process. The results showed that the bioconcentration factor did not differ significantly between the selected species (0.01 - 0.03). Citric acid was added in doses (50 mL, 30 mM) until the first effects of uranium phytotoxicity appeared. After four doses of citric acid, the bioconcentration factor reached 0.05 for both plants. The increase of uranium content taken up by the respective plants was more pronounced. Thus, the uranium content of sage grown in contaminated soil (470 mg/kg) increased from 6.03 to 21.28 mg/kg in citric acid-treated soil. The data obtained confirmed the efficiency of citric acid in enhancing phytoextraction of uranium and further suggest that even plants of a rather small biomass can be useful in phytoremediation given the appropriate treatment through induced phytoextraction with appropriate chemical agents.

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 56, 1-6.

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The Determination of Total Serum Bilirubin Concentration in Type 2 Diabetes patients Original Scientific Article

 

Mandal Šaćira

DOI: 10.35666/2232-7266.2021.56.02
 
UDK: 543.64:616.379-052
 

Abstract: Bilirubin represent a natural end-product of heme metabolism and is used as as a marker in diagnosis off hepatobiliary diseases. Recent studies demonstrated that serum bilirubin levels are related to the risk of Type 2 diabetes mellitus (T2D) development and subsequent complications. The aim of this study was to analyzed serum total bilirubin concentrations and its relationship with biochemical and clinical characteristics in T2D patients. Total of 109 participants were included in this study, 54 controls and 55 diabetic patients, both gender, while ages ranged from 35 to 70 years. Biochemical parameters were analyzed by standard IFCC methods while serum total bilirubin concentrations was determined by the method of Jendrassik/Gróf. All analyses and measurements were provided by using the chemical analyzer VITROS 350. Results showed a significant difference in concentrations of glucose, glycated hemoglobin (HbA1c), lipid profile (total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol) and bilirubin between T2D patients and controls (p<0.05). Also, significant association was found between bilirubin and glucose concentrations in two investigated populations (p<0.05). It appears that elevated concentration of bilirubin and biochemical characteristics are associated with the progression development of Type 2 diabetes and its related vascular complications. Therefore, total serum bilirubin concentrations could be used as potential T2D biomarker and therefore, as new therapeutic target.

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 56, 7-12.

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The Content of Essential and Toxic Metals in the Hair of Children with Autistic Spectrum Disorders Original Scientific Article

Pilić, S.,a Kalić, E.,a Selović, A.b

 

DOI: 10.35666/2232-7266.2021.56.03

UDK: 615.9:612.799-056.34(497.6)

 
 

Abstract: The aim of this study was to assess the possible relationship between the content of essential and toxic metals in the hair samples with the etiology of autism spectrum disorder (ASD) in children from Bosnia and Herzegovina. Taking into account the age and gender of the child, in the study and control group, the samples were divided into three subgroups (1-5 years; 6-9 years; 10-14 years). Altered profiles of the values of the Cu, Fe, Mn, Zn, Cd, Co, Cr, Ni, Pb in the study group were observed in comparison with the control group children with typical neuromotor development. Higher values of toxic metal concentrations (Co, Ni, Cd, Pb) were found in boys, compared to the girls in the study group. The content of Pb in the study group was higher in all three ages compared to their controls, with the difference being especially pronounced in the age group 1-5 years (6.64 mg/kg; 1.89 mg/kg). A strong correlation between the content of Pb and Cd (0.93) was confirmed. Lower values of Cr concentration and higher of Ni, Cu and Fe were recorded in the study group. Statistically significant differences (p<0.05) were found in Zn concentrations (6-9 years; 10 -14 years) between the control and study groups. The findings help highlight the role of heavy metals as environmental factors in the etiology of ASD.

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 56, 13-20.

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Serum levels of non-enzymatic antioxidants in female dementia patients with respect to the degree of cognitive impairment Original Scientific Article

Lepara, O.a, Ibragić, S.b*, Rebić, D.c, Zukić, E.d, Krupić, F.e, Džubur, A.fFajkić, A.g, Pepić, E.g, Novaković, A.d, Gojak R.h

 

DOI: 10.35666/2232-7266.2021.56.04

UDK: 612.015:616.894-052

 

Abstract: The aim of this study was to investigate the correlation between the severity of cognitive impairment in Alzheimer’s disease (AD) and vascular dementia (VD) and the serum antioxidant status of uric acid (UA), albumin (ALB) and bilirubin (BIL) in female patients. The cross-sectional study included 90 subjects, aged ≥65, divided into three groups: 30 patients with AD, 30 patients with VD and 30 control subjects. For cognitive assessment, all participants underwent the Montreal Cognitive Assessment (MoCA). Serum concentrations of ALB, UA and BIL were determined spectrophotometrically. The AD patients had a significant decrease of UA and increase of serum BIL. Upon stratification according to the degree of cognitive impairment, lower UA concentrations were found in patients with severe cognitive impairment, whereas increased BIL was found in patients with moderate cognitive impairment. Patients with VD were characterized by hypoalbuminemia and upon stratification this finding was evident among patients with severe cognitive impairment. The MoCA score correlated positively with BIL in AD patients. The obtained data supports the protective role of serum antioxidants in the pathogenesis of dementia. Further on, we suggest further longitudinal research to confirm the combined use of these parameters as potential biomarkers in AD and VD.

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 56, 21-28.

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Relationship between platelet indices and lipid status in chronic hookah consumption Original Scientific Article

Kurtović A.a, Fajkić A.b, Pepić E.b, Pleho-Kapić A.b, Lepara O.c, Lazzari D.d, Milaimi A.d, Milaimi A.d, Meštrovac A.d, Dervišević A.c, Mačkić-Đurović M.e, Mušanović J.f

 

DOI: 10.35666/2232-7266.2021.56.05

UDK: 688.932-056.83 : [616.155 + 611.1]

 

Abstract: Hookah smoking is a growing trend, both in the world and in Bosnia and Herzegovina. The aim of this study was to determine the value of platelet indices in hookah smokers and find out associations with lipid profile. Cross-sectional study included 60 students (30 chronic hookah smokers and 30 non-smokers). The complete blood count (erythrocytes, leukocytes, platelets, hemoglobin, hematocrit, erythrocyte and platelet indices), lipid parameters (total cholesterol, triglycerides, LDL-C, HDL-C) were determined.  The platelet count, mean platelet volume and MPV/Platelets ratio were statistically significantly higher in chronic hookah consumers in the student population than in the control group (p <0.001). In addition, platelet count was in significant positive correlation with values of total cholesterol, LDL-C and negative correlation with value of HDL-C, while there was a significant negative correlation between mean platelets volume, and MPV/Platelets ratio with  HDL cholesterol levels in chronic hookah smokers (p <0.05). These findings suggest that chronic hookah consumption could be associated with the development of atherosclerotic changes in blood vessels, which could lead to the development of long-term consequences on the cardiovascular system's function.

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 56, 29-34.

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Bulletin of the Chemists and Technologists of Bosnia and Herzegovina

 

 

Issue 57

 

 

 

Publication date: December 2021

 

Full version Bulletin

 

Table of contents


Seeking the right balance between three teaching approaches: a quasi-experimental study in the context of learning about thermal phenomena Original Scientific Article

 

Kolenda, D., Vidak, A.

 

DOI: 10.35666/2232-7266.2021.57.01

UDK: 542-053.5:37.018.2

 

Abstract: In this study, we investigated which teaching approach may be optimal to facilitate learning about thermal phenomena in primary school. Concretely, we conducted a pretest-posttest quasi-experiment that included 45 eighth-grade students divided into three groups. In the first group (a non-interactive teacher-centered approach), the teacher gave an experiment-based lecture on converting thermal energy into mechanical work. In the second group (a teacher-centered interactive approach), the teacher gave the same experiments-based lecture, but interacted much more with the students and encouraged them to think about the demonstrations. Finally, in the third group, the student-centered interactive approach was applied. The results of the ANCOVA showed that the three teaching approaches were equally effective in developing students’ understanding of thermal phenomena. However, closer analyses showed that students who learned from the teacher-centered interactive approach significantly outperformed their peers when it came to understanding basic thermal concepts approach, students worked in small groups to conduct the same experiments and “discover” the same relationships that the teacher had introduced in the previous one.

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 57, 1-8.

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Occurrence of the heavy metals and PCBs in Accumulation Lake Modrac Original Scientific Article

 

Marjanovic, A., Djedjibegovic, J., Omeragić, E., Sober, M.

 

DOI: 10.35666/2232-7266.2021.57.02
 
UDK: 543.[628.312.2:549.28] (497.6-18 Modrac)
 
 

Abstract: The accumulation Lake Modrac is a particularly important source of drinking water for inhabitants of the Tuzla region and few local settlements.The most significant point sources of organic contaminants in the accumulation Lake Modrac are waste water from households and industry. In this area, most of the settlements have neither sewage systems nor facilities for waste water treatment. Other potential point sources of pollutants are industrial plants. The most prominent are coal mines (Banovići and Đurđevik), metal and wood industry, plant for plastic production, and  oil and oil derivatives warehouse.Few previously conducted surveys in the region showed the presence of the persistent organic pollutants and heavy metals in large extent. The objective of this study was to conduct a water quality survey targeting selected inorganic (Cd, Cr, Cu, Hg, Ni, Pb and As) and organic pollutants in the accumulation Lake Modrac in Bosnia and Herzegovina.  The content of polychlorinated biphenyls (PCBs) determined with ELISA test, ranging from  3.23 to 6.19 µg/L (sum of 7PCBs).The most abundant metals (analyzed by graphite furnace AAS and mercury analyzer) at all five sampling locations were Pb (6.79-36.58 µg/L); Ni (5.81-10.43 µg/L) and Hg (1.08-6.10 µg/L).

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 56, 9-16.

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Smoking effect on the cadmium and zinc concentration in smokers and nonsmokers Original Scientific Article

 

Pepić, E., Šečić, D., Lepara, O., Kapić-Pleho, A., Kurtagić-Pepić, E., Mušanović, J., Metović, A., Džubur, A., Naser, N., Panjeta, M., Alić-Džubur, A., Voljevica, A.

 

DOI: 10.35666/2232-7266.2021.57.03

UDK: 613.84 [546.48:546.17]

 

Abstract: Studies have shown that cigarette smoking affects the accumulation of some heavy metals in certain tissues and metabolism of essential elements. The aim of the study was to determine the differences in the concentrations of cadmium in the blood and urine and zinc in the urine of smokers and ex-smokers in relation to non-smokers, and to determine the possible influence of cadmium concentration on zinc excretion as an essential element. The study included 106 subjects. Subjects were regular smokers (n=51), ex-smokers (n=38) and non-smokers (n=17).  Atomic absorption spectrophotometry (AAS) with an electrothermal atomizer was used to determine cadmium. Zinc was determined by AAS with a flame atomizer. There was a significant difference in the values of cadmium in the blood between the groups: smokers and non-smokers (p<0.001), smokers and ex-smokers (p <0.001), and between ex-smokers and non-smokers (p = 0.045). There is a significant positive and strong correlation in the level of zinc and cadmium in urine per gram of creatinine, and as the level of cadmium increases, the level of zinc also increases (rho=0.781; p=0.001). The data indicate that cigarette smoking has been shown to be a factor that can increase cadmium levels to an extent that will significantly increase zinc excretion, or its increased loss.

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 56, 17-26.

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