Issue 39

  

 

 

 

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina

 

 

Issue 39

 

 

Publication date: December 2012

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Table of contents


 

One-Shot Chemiluminescence Biosensor for Determination of Glucose in Soft Drinks Original Scientific Article

Čopra-Janićijević Amira, Tahirović Azra, Kalcher Kurt

Abstract: The preparation of a new biosensor for glucose was based on the fact that glucose can be determined  by  its  enzymatic  oxidation  to  gluconic  acid  with  simultaneous  formation  of  hydrogen peroxide in the presence of glucose oxidase. Hydrogen peroxide formed in previous reaction further reacts  with  luminol  in  presence  of  cobalt  as  catalyst  producing  chemiluminescence  signal.  This biosensor  was  made  of  three  layers.  The  first  layer contained  luminol,  sodium  phosphate,  sodium lauryl  sulphate  as  a  surfactant  and  a polymer,  hydroxyethyl  cellulose  as  a  carrier  applied  to  the support.  The  second  was  an  aqueous  solution  of  Co2+as  a  catalyst,  and  the  third  layer  was  an aqueous solution of glucose oxidase. After applying the sample solution (glucose) by  micropipette onto the sensor, glucose reacted with glucose oxidase and hydrogen peroxide was formed. Hydrogen peroxide diffused towards the polymeric layer containing luminol and produced chemiluminescence reaction. The detection limit for the new glucose biosensor (3σ) was found to be 19 mg L-1 glucose (σ from 5 determinations of 30 mg L-1). A relative standard deviation of 7.6 % was recorded for 10 measurements of 50 mg L-1 standard glucose solution, and 6.8 % for 10 measurements of 500 mg L-1 standard glucose solutions. The glucose biosensor was used for the determination of glucose in soft drinks  (mainly  apple  juices).  The  results  obtained  with  the  chemiluminescence  sensors  and commercial  glucometer  (as  the  reference  method)  are  in  good  agreement.  The  corresponding recovery rates were between 93 and 105 %.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 39, 1-6.

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Variation of PM10, NO2, NO and O3 in City of Mostar, Bosnia and Herzegovina Original Scientific Article

Buntić Nikolina, Kraljević Tomislav, Talić Stanislava

Abstract: Pollutants such as particulate matter PM, nitrogen oxides and troposferic ozone are harmful to a human health. Study of pollutant variation and its relationship is of importance not only for environmental protection but also for the benefit of public at large. The aim of this study was to analyze seasonal and daily variation of PM10, NO2, NO and O3 in a residential part of an urban area. The study was conducted from January 1 till December 31, 2011 in the City of Mostar using the following methods: absorption of beta radiation, chemiluminescence and UV photometry. The results presented in this article, show the dependence of air pollution levels upon traffic density and seasons. Considering the level of air pollution relative to the regulated limited and tolerated values, the measured 24-hour concentrations of all studied pollutants did not exceeded  the limited values and tolerated values.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 39, 7-10.

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Determination of Radionuclide Activity of U-238 in Wheat using Gamma Spectrometric Method Original Scientific Article

Islamović Safija, Radović-Rajević Gordana, Zovko Emira

Abstract: Migration and accumulation of contaminants in soil is complex and involves different processes such as leaching, capillary movement, sorption, nutrient resuspension in roots and into the atmosphere. Speciation of radionuclides in ecosystems depends on the source and layoffs, the distance from the source, dispersion processes and deposition conditions. Resuspension of radionuclides from the soil surface to the outer portions of the plants occurs due to the action of rain and wind. Significant variations in contamination can be expected depending on the type of plant, plant growth conditions and methods of its preparation before consumption. In this study we determined the activity of radionuclides U-238 in the aerial part of wheat that was sown on a sample of soil from Hadzic, and as an added contaminant different uranyl acetate concentrations were used. Gamma spectrometric measurements were carried out in a vertical coaxial HPGe detector. It is concluded that, regardless of the concentration of the contaminant, if the plant has a sufficient amount of essential elements, in this case potassium, it will not take an element that is harmful to its development, such as the uranium-238, which belongs to the toxic and unnecessary elements in plant nutrition.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 39, 11-14.

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Phenolic Compounds and Antioxidant Activity of Extracts of  Nigella sativa L. Original Scientific Article

Goga Amila, Hasić Sabina, Bećirović Šejla, Ćavar Sanja

Abstract:Nigella sativa L. (Black cumin) is an annual herbaceous plant which belongs to family Ranunculaceae. The plant commonly grows in the Middle East, Eastern Europe and Western and Central Asia. This plant has been extensively investigated in recent years, due to its notable pharmacological properties. This work presents the investigation of phenolic content and antioxidant activity in extracts obtained from seeds of N. sativa, using Soxhlet and ultrasound extraction techniques. Total phenolics content was measured using the Folin-Ciocalteu method, and they varied from 11.867±0.338 to 31.148±0.293 mg/g GAE. Radical scavenging activity of the samples was examined using two methods, 1,1-diphenyl-2-picrylhydrazyl (DPPH), and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid), (ABTS) test, and reducing power of these samples was examined by reducing ferric, and molybdenum cations. All examined samples showed prominent antioxidant activity, except p-cymene. Thymoquinone and ethanolic extracts revealed the best results among six investigated samples.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 39, 15-19.

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Synthesis and Characterization of Novel Chloro-Ru(III) complex with Formamide Original Scientific Article

Dugandžić Vera, Kahrović Emira

Abstract: A new neutral complex has been synthesized in reaction of [RuCl6]3- with formamide in mixed solvent ethanol-water (10:1). Obtained olive green substance was characterized by mass spectrometry, CHN elemental analysis, IR and UV-VIS spectroscopy. Based on experimental data, compound was formulated as [RuCl3(HCONH2)3]x0,5C2H5OH. Relative molecular mass of synthesized compound was determined by MALDI-TOF mass spectrometry as adduct with K+ ion to have value of 382.8485. IR spectrum of formamide, indicates coordination through the amide carbonyl oxygen, which is indicated by shift of carbonyl absorption from 1681 cm-1 in free formamide to 1636 cm-1 in synthesized compound. UV-VIS spectrum of synthesized compound in water shows LMCT absorption centered around 300 nm. Hydrolytic profile indicates that compound hydrolyses with fast exchange of first chloride ion with water molecule.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 39, 21-23.

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Total Phenolic Content and Antioxidant Capacity of Fruit Juices Original Scientific Article

Keskin-Šašić Irmina, Tahirović Ismet, Topčagić Anela, Klepo Lejla, Salihović Mirsada, Ibragić Saida, Toromanović Jasmin, Ajanović Atifa, Velispahić Elmir

Abstract: The interest in polyphenolic antioxidants has increased remarkably in the last decades due to of their elevated capacity in scavenging free radicals associated with various human diseases. Previously, some fruits were shown to contain high antioxidant activities. Fifteen fruit juices were analyzed for total phenolic content and antioxidant capacity (oxygen radical absorbance capacity, ORAC). The total phenolic content (TPC) was measured by Folin-Ciocalteu assay and gallic acid used as standard. TPC varied from 7.3 mg GAE/100 mL for aloe vera juice to 71.8 mg GAE/100 mL for cranberry juice. The value of antioxidant capacity was determined by ORAC test, using 2,2'-azobis(2-amidino-propane) dihydrochloride as reactive species and Trolox as a standard. Obtained values were from 27.1 μmol TE/100 mL for aloe vera juice to 1271.8 μmol TE/100 mL for black currant juice. Results from  the present study suggest further analysis on chemical composition of samples in order to identify compounds that might be responsible for antioxidant activity.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 39, 25-28.

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The Impact of the Content of Lead Oxide on the Porosity and Volume of the Pores, Paste and Active Mass of the Positive Electrodes-Pasted Flat Plates of Lead-Acid Batteries Original Scientific Article

Avdić Nurudin

Abstract: Porosity and the volume of the pores of active mass of lead-acid layout battery are one of the key factors that determine the capacity and their lifetime. Increase of pore diameter enables flow of sufficient quantitiy of electrolyte into the bulk active mass and, as a consequence, enables its maximum conversion. Smaller diameter of the pores in the same volume of active mass provides a larger surface area which has again a consenquence of higher capacity for the ephemeral dischargings, but also faster filling in of the pores with the compenents of electrochemical reaction, which in turn reduces their lifespan. The aim of this work was to consider the impact of different content of the lead oxide in lead powder as the main component in the production of these batteries regardings this phenomenon.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 39, 29-33.

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Effect of Plant Nutrients on Antiradical Activity of In Vitro Cultivated Broccoli (Brassica oleracea L. var. italica Plenk.) Original Scientific Article

Čakar Jasmina, Parić Adisa, Maksimović Milka, Bajrović Kasim

Abstract: Environmental conditions may have impact on plant metabolism, especially on secondary metabolism. As a result of different stress circumstance, plants have developed different protective mechanisms and major one is production of secondary metabolites. Plant growth conditions could be controlled and modified in in vitro plant culture, which usually results in higher or lower contents of secondary metabolites. We have established a rapid protocol for in vitro germination and cultivation of Brassica oleracea L. var. italica Plank. Three, ten, twenty and thirty days old seedlings, cultivated on three different  Murashige-Skoog (MS) media, as well as two types of spontaneously induced calli were used for extraction. Ethanolic plant extracts were tested for their antioxidative potential using 2,2’-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging method. Extracts from three days old seedling demonstrated the highest antioxidative potential. On the other hand, extract of broccoli seedlings cultivated  on basal MS medium have shown prooxidative properties that can be contribute to prooxidative properties of some unknown component in the presence of free transition metal ions, the type of oxidizable substrate in use, as well as to the biological environment in which they act.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 39, 35-38.

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Theoretical Studies of Structures and Thermodynamic Parameters of Melatonin and its Metabolites: N1-Acetyl-N2-formyl-5-metoxy kynuramine and N1-Acetyl-5 metoxykynuramine Original Scientific Article

Galijašević Semira, Hodžić Elvisa

Abstract: Melatonin, a neurohormone is  well known regulator of a number of physiological processes. In addition, numerous studies both in vitro and in vivo showed a strong antioxidant and free radical scavenging activity usually considered as a result of direct melatonin reactivity. However, two major metabolites of melatonin, N1-acetyl-N2-formyl-5-metoxy kynuramine (AMFK) and N1-acetyl-5-metoxykyunaramine (AMK) also showed strong free radical scavenging activity, but towards different biological free radicals. Melatonin oxidation mechanism in a complex biological environment has been studied at different conditions but still is partially understood. Reactivity of the molecule is always governed but its electronic properties and kinetic and thermodynamic stability. Thus, we performed theoretical calculations using Density Functional Theory (DFT) at with B3LYP/6-31G* basis set to calculate geometries, atomic charges and thermodynamic parameters for all three molecules. Semi-empirical calculations at PM1 level are also performed and compared with DFT data. Calculated atomic charges showed that nitrogen atoms as the most possible sites for interactions with electrophilic species such as free radicals. Oxygen atom in metoxy group also shows pronounced negative atomic charge. The most stable molecule is AMFK, followed by AMK and melatonin respectively. This trend can partially explain high melatonin reactivity and its fast decomposition in biological systems. Obtained values calculated at semi-empirical and ab inition levels  are significantly different implying that conclusions based on calculations done at lower levels of theory can not be used as reliable when explaining experimental data.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 39, 39-43.

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The Cellulose and Paper Industry Wastewater Treatment Technical Article

Goletić Šefket, Avdić Nurudin

Abstract: A large amount of water is used in the cellulose and paper industry, which causes the production and release of the industrial wastewater which can, due to the amount and loads of contaminants, significantly affect the quality of the water environment if the adequate meassures for the rational use and purification of the same are not implemented and continuously applied. These wastewaters have a large organic contamination (BOD5 and COD), a large sulphite concentration, phenol and tannin (lignin) and chemicals that are used in the process of cellulose and paper production. The treatment of the wastewater from the cellulose and paper production in “Natron–Hayat“ Maglaj after the realization of the wastewater disposal project done in 2007 is analyzed in this paper. This company has accomplished the project of recovery and modernization of the wastewater purification system towards the rational use and efficient purification of the industrial waters. With the device efficiency analysis for the wastewater treatment it was concluded that the purification efficiency level is acceptable according to the emissions standards issued by the regulations for the terms of wastewater release into the natural recipients and public sewerage system. Thereby, this company has significantly contributed to the water resources protection, ie river Bosna, which is a recipient of the wastewaters released from this company's plant. However, it would be good to analyze the possibility of the optimization of this device in oreder of exploiting the biogas as a potential fuel, adn sludge as a potential fuel and for other purposes.

Bulletin of the Chemists and Technologists of Bosnia and Herzegovina 39, 45-49.

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