In this paper, we report surface dielectric and photodielectric properties of low density polyeth... more In this paper, we report surface dielectric and photodielectric properties of low density polyethylene (LDPE)/Emodin composite. Emodin was extracted from Fallopia japonica plant. The composite was obtained from the xylene solution. Dielectric measurements were performed in the frequency range from 240 Hz to 4 kHz and the temperature range from 20 °C – 70 °C. Irradiations of the sample were applied before and during measurement with selected wavelengths from UV to the visible range. Surface dielectric conductance and susceptance of the LDPE/Emodin composite is higher then value of conductance and susceptance of pure LDPE. We found an increase, by one order of magnitude, in conductance and susceptance of the LDPE/Emodin composite with increase of measurement frequency. Furthermore, the surface conductance and susceptance increase due to UV radiation in mentioned temperature range, but during visible radiation at frequency 1 kHz (except in the case green LED lamp) we observed the enhan...
Macedonian Journal of Chemistry and Chemical Engineering
The contents of polyphenolic components (total polyphenols, flavonoids, and monomeric anthocyanin... more The contents of polyphenolic components (total polyphenols, flavonoids, and monomeric anthocyanins) and vitamin C, and the bioactive potential (antioxidant, antiproliferative, and antihyperglycemic activities) of wild cornelian cherry were determined. Samples were collected from four different locations in Bosnia and Herzegovina. Sample CC3 from Drinić had the highest monomeric anthocyanin content (1.40 mg CyGE/g FW) and the highest inhibition of free radicals (IC50 DPPH = 262.19 mg/ml; IC50 ABTS = 76.78 mg/ml; IC50 OH˙ = 102.31 mg/ml) and inhibition of breast adenocarcinoma cell line growth (IC50 MCF-7 = 1.37 mg/ml). Sample CC4 from Drvar showed the highest total polyphenol (55.92 mg GAE/g DW) and vitamin C (88.74 mg/g FW) contents. Sample CC4 significantly inhibited the growth of cervix epithelioid carcinoma (IC50 HeLa = 0.62 mg/ml) and lung adenocarcinoma (IC50 A549 = 0.48 mg/ml) cell lines, and αglucosidase (IC50 AGHA = 0.466 mg/ml). Wild cornelian cherry could be used as a functional food with beneficial pro-health properties.
The results of determination of non- enzymatic antioxidant capacity tomato variety “volovsko srce... more The results of determination of non- enzymatic antioxidant capacity tomato variety “volovsko srce” are presented in this paper. Content of total phenols is between 88.81 to 138.44 µgGAE/gFW, total flavonoids from 59.25 to 66.95 µgQc/gFW, and flavonols from 94.49 to 243.47 µgQc/gFW respectively. The content of lycopene in the samples ranged from 136.32 to 600,3 µg/100gFW, while we determined and the content of vitamin C , which is 12.6 to 15.87 mg/100gFW for 3 different sample probes. The results of antioxidant activity of ethanolic extract of tomato variety “volovsko srce” obtained using DPPH and ABTS methods as compared to Trolox equivalent antioxidant capacity are: DPPH ranged from 1.81 to 2.54 µmol Trolox/gFW, for ABTS from 0.19 to 2.23 µmol Trolox/gFW. The results are in agreement with literature data , but it is most likely to some differences due to different ways of breeding samples.Rezultati određivanja neenzimskih antioksidativnih kapaciteta paradajza sorte „Volovsko srce“ ...
In this paper, the antioxidant activity of 3 red wine samples was determined using 1,1- diphenyl-... more In this paper, the antioxidant activity of 3 red wine samples was determined using 1,1- diphenyl-2- picrylhydrazil (DPPH)- radical scavenging assay, 2,2’- azino- bis- (3- ethylbenzothiazoline-6- sulfonic acid) (ABTS) radical scavenging assay, so as Briggs- Raushers oscillatory reactions. Correlation of these antioxidant methods with the total phenol content in these red wine samples was also performed. The total phenol content was found to vary from 1790,67- 3209,97 mgGAE/Lwine. Antioxidant activity determined by DPPH method 15,45- 17,08 mmolTrolox/Lwine, ABTS method 23,21- 24,14 mmolTrolox/Lwine, and Briggs- Raushers oscillatory reactions 1,826- 3,848 mmolTrolox/Lwine respectively. The total phenol content shows signifficant correlation with ABTS method (0,55), and very signifficant correlation with Briggs- Raushers oscillatory reactions (0,99)U ovom radu određena je antioksidativna aktivnost 3 uzorka crvenih vina primjenom gašenja 1,1- difenil- 2- pikrilhidrazil (DPPH)- stabilnog ...
Wealthy chemical composition of peppers with excellent organoleptic properties (taste, color, sme... more Wealthy chemical composition of peppers with excellent organoleptic properties (taste, color, smell) makes it almost indispensable in the daily diet. The subject matter of this paper is hybrid variety of fresh pepper Bibic F1. Content of each component chemical composition: dry matter (5.78%), total ash (0.36%), total acidity (0.13%) and vitamin C (70.4 mg per 100g), was determined by AOAC methods and was in agreement with literature data. Content of some minerals determined by atomic emission spectrometry (ICP-OES). The amount of each element in 100 g of fresh pepper hybrid variety Bibic F1 was: sodium (3.3 mg), potassium (180.2 mg), magnesium (9.8 mg), calcium (12 mg), phosphorus (23.2 mg), iron (0.72 mg), copper (0.04 mg), zinc (0.2 mg) and manganese (0.11 mg). Fresh pepper hybrid variety Bibic F1 is not a significant source of minerals in the diet.Bogat hemijski sastav paprike sa izvanrednim senzornim svojstvima (ukus, boja, miris) čini je gotovo nezamjenjivom u svakodnevnoj ish...
Allium ursinum is a plant, more known as sremus, crijemus, wild or bearded onion. In nutrition it... more Allium ursinum is a plant, more known as sremus, crijemus, wild or bearded onion. In nutrition it is used as a vegetable (salad and spice), and in human medicine, as an auxiliary agent. It is significant due to its nutritional and healing value. Since diet is largely used seasonally and in fresh state, as a salad, it can be a significant source of some nutrients, such as mineral matter, which are of great importance for human health. Considering the polemics about sremus as a "source of health" we decided to analyze content of mineral matter, macro and micro elements in sremus, with four different locations of the northwest part of Repulic of Srpska. Sodium concentrations were determined from 31,065 to 32,905 mg / kg, potassium from 4703.06 to 4803.485mg / kg, calcium from 1532.545 to 1559.095 mg / kg. Microelements included nickel (0.358 to 0.388 mg / kg), cobalt, aluminum. Mineral matter was determined by atomic absorption spectrophotometry ICP OES spectroscopy after wet...
JOURNAL OF ENGINEERING & PROCESSING MANAGEMENT, 2020
The aim of this paper is to develop specification for the production of roasted coffeewith improv... more The aim of this paper is to develop specification for the production of roasted coffeewith improved nutritional quality. In this respect, the influence of different coffeeblends and temperatures of roasting on the antioxidant activity of coffee was examined.Also, the composition of some bioactive components in the analyzed sampleswas determined. Two Arabica coffees of different quality and Robusta coffee wereused for the preparation of coffee blends. Experimentally determined green coffeeblends B1, B2 and B3 were roasted at 167◦C, 171◦C and 175◦C for 25 minutes inorder to establish the effect of roasting temperature on the antioxidant activity andthe content of bioactive components in blends. Based on the results of DPPH andABTS test, coffee blends B3 and B2, roasted at 171◦C, had the highest (P<0.05)antioxidant activity. Those coffee blends had higher content of Robusta coffee thancoffee blend B1. Results of this research can provide opportunities for the developmentof roasted g...
The complexity of ecological conditions in urban areas imposes the plant species need for the dev... more The complexity of ecological conditions in urban areas imposes the plant species need for the development of various biochemical and physiological adaptive strategies. The aim of our research was to examine the antioxidative and antifungal metabolism of species Pinus nigra, Picea omorika, Tilia cordata and Betula pendula from the area of Banja Luka City (urban area) during two vegetation seasons (spring and autumn) and compared with the same species from forest habitats. Changes in the protein concentration, activity and isoenzyme profiles of peroxidases (POD, EC 1.11.1.7), content and antioxidative activity of total phenols and antifungal activity in leaves and needles of the plants from the urban area and forest habitats were monitored. The obtained results indicate that urban areas induce changes in antioxidative metabolism in all examined species, but that the response is species specific. The most sensitive parameter that indicates different adaptation strategy of Pinus nigra, Picea omorika, Tilia cordata and Betula pendula to environment conditions in the urban area were peroxidase isoenzyme patterns. Less specific parameter was phenol content even though there are some indications for role of their antioxidative capacity in the adjustment to specific habitat. In addition, each species had different metabolic strategy to cope with the changes caused by the urban environment.
GLASNIK HEMIČARA, TEHNOLOGA I EKOLOGA REPUBLIKE SRPSKE, 2018
Proteoliza sarkoplazmatičnih i miofibrilarnih proteina je vrlo važna biohemijska pojavakoja se ja... more Proteoliza sarkoplazmatičnih i miofibrilarnih proteina je vrlo važna biohemijska pojavakoja se javlja u toku zrenja fermentisanih proizvoda od mesa. Kao rezultat aktivnostiproteinaza i peptidaza, povećava se sadržaj polipeptida, peptida i slobodnih aminokiselina,koji učestvuju u razvoju mirisa, ukusa i teksture. SDS-PAGE elektroforezom analiziranisu proteinski profili domaćih fermentisanih kobasica sa dodatkom 0,5% i 1,5% izolatasurutke i soje. Pripremom uzoraka razdvojene su sarkoplazmatične i miofibrilarne frakcije.Denzitometrijski su preračunate molekulske mase proteina. Praćene su kvalitativnepromjene proteina nadjeva, kobasica nakon zrenja i tokom šestomjesečnog čuvanjavakuum pakovanih uzoraka na temperaturi od +4°C.Biohemijske promene, u osnovi, se malo razlikuju. Dinamika promjene elektroforetskihprofila sarkoplazmatičnih i miofibrilarnih proteina, pokazuju veoma slične tendencije.Elektroforetska slika miofibrilarnih proteina nadjeva prije punjenja u crijeva nam pokazujeda su...
Acta Scientiarum Polonorum Technologia Alimentaria, 2016
Background. Coff ee is one of the most widely consumed beverages in the world, because of its uni... more Background. Coff ee is one of the most widely consumed beverages in the world, because of its unique sensory properties and physiological properties. Coff ee beverages represent a signifi cant source of antioxidants in the consumers' diet and contribute signifi cantly to their daily intake. The aim of this research was to investigate the eff ect of diff erent roasting degrees on the content of biologically active compounds and antioxidant activity in diff erent quality classes of Arabica coff ee. Materials and methods. Samples of green Arabica coff ee (Rio Minas) of two quality classes from two production batches were used for the research. Roasting was carried out at temperatures of 167, 175 and 171°C. The total phenol content (TPC), total fl avonoid content (TFC), fl avonol content (FC) and antioxidant activity (DPPH, ABTS) in the coff ee extracts was determined. Results. This research shows that TPC was signifi cantly higher (P < 0.05) in green coff ee compared to TPC in roasted coff ee, and TPC decreases as the roasting temperature increases. TFC and FC were signifi cantly lower (P < 0.05) in green coff ee than in roasted coff ee. Diff erences in TPC between the 1 st and 2 nd classes of Arabica coff ee were not signifi cant (P > 0.05), while diff erences in TFC were signifi cant (P < 0.05) only for green coff ee from the second production batch and diff erences in FC were signifi cant (P < 0.05) for green coffee and for coff ee roasted at 175°C. Roasting temperatures have diff erent infl uences the antioxidant activity (DPPH, ABTS) of coff ee and the highest antioxidant activity was determined in coff ee roasted at 171°C. An exception was 1 st class Arabica coff ee roasted at 167°C (ABTS). All samples of 1 st class Arabica coff ee had higher antioxidant activity (DPPH, ABTS) compared to 2 nd class Arabica. Conclusions. This research shows that the bioactive compounds content and antioxidant activity of diff erent quality classes of Arabica coff ee are dependent on the degree of roasting. TPC decreases when the roasting temperature increases, while TFC and FC also increase. These results indicate that the antioxidant activity of coff ee depends on a variety of bioactive components in coff ee beans. Antioxidant activity largely depends on the class of coff ee. The coff ee samples of 1 st class quality (maximum 8 black beans/300 g from the sample and large bean size) had higher antioxidant activity compared to samples of 2 nd quality class (maximum 19 black beans/300 g in the sample and medium-sized beans).
Ethanolic (50%, v/v) extract of Reynoutria japonica Houtt. rhizome from the Banja Luka region was... more Ethanolic (50%, v/v) extract of Reynoutria japonica Houtt. rhizome from the Banja Luka region was prepared. The dry extract was dissolved in methanol, and total phenols content, antimicrobial and antioxidative activities were determined. The total phenols content was determined using modified Folin-Ciocalteu method, the antimicrobial activity by monitoring the optical density, and antioxidative activity by the method of quenching stable free 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals by FRAP and ABTS metods. The antioxidative activity results were compared with control antioxidants: vitamin C, BHA and BHT. In order to determine the antimicrobial extract activity, E. coli, S. aureus and B. cereus were used as test microorganisms. The paper discusses the results of antimicrobial and antioxidative activeties of the R. japonica extract with respect to extract concentration as well as to total phenols content. The extract of R. japonica rhizome shows both, a significant overall antiox...
Samples of stinging nettle or common nettle (Urtica dioica L.) were collected from the area of Ba... more Samples of stinging nettle or common nettle (Urtica dioica L.) were collected from the area of Banja Luka. To measure and evaluate the content of chlorophyll (a and b), carotenoids, and soluble proteins, as well as peroxidase activity (POD, EC 1.11.1.7.), fresh nettle leaves of different developmental stages were used. Dried nettle leaves were used to obtain ethanol extract. The dry residue of ethanol extract was dissolved in methanol and the obtained solution was used to determine the content of total phenols, flavonoids, flavonols, as well as non-enzymatic antioxidant activity and antimicrobial activity. The non-enzymatic antioxidant activity was determined by different methods: FRAP, DPPH, and ABTS. The results were compared to those of standard substances like vitamin C, BHT, and BHA. Antimicrobial activity was screened by using macrodilution method. The obtained results showed insignificantly higher content of chlorophyll, carotenoids, and proteins in young nettle leaves as wel...
The aim of this study was the determination of the antioxidant and antihyperglyce-mic effect of w... more The aim of this study was the determination of the antioxidant and antihyperglyce-mic effect of wild grown rosehip and pomegranate fruit extracts, and the determination of the polyphenolic content (total phenols, flavonoids, flavonols, flavan-3-ols and total and monomeric anthocyanins). The antioxidant activity of rosehip fruit in view of stable DPPH and ABTS radicals was higher comparing to pomegranate fruit, while according to the OH radical these two samples showed a similar effect (94.17 and 92.03 mg/mL). A dry rosehip fruit extract was found to have a 1.6 times more pronounced antihyperglycemic activity (1.42 mg/mL) compared to the dried pomegranate fruit extract (2.26 mg/mL). The content of total phenols of rosehip fruit was 8.75 mg GAE/g FPM and 22.01 mg GAE/g DPM , higher than the content of total phenols of pomegranate fruit (3.44 mg GAE/g FPM and 15.43 mg GAE/g DPM). The content of total phenols in rosehip and pomegranate fruits was higher than the content of total flavono...
The isolation, chemical and microbiological characterization of essential oils originate from tob... more The isolation, chemical and microbiological characterization of essential oils originate from tobacco dust where performed. The main source of subjected tobacco dust was technological process of Tobacco Factory Banja Luka. In extracted essential oils 25 components where identified. Simultaneousl\ , in the petrol ether extract where identified 31 component. The main compounds of extracted essential oils are Neophytadiene and Solanone. The main compounds of petro: ether extract are Nicotine, Neophytadiene, Sorbitol and Neodihydrocarveole. The microbiological activity examination was showed significant antibacterial affection of extracted essential oils and petrol ether ex ract on Escherichia coli, Staphylococcusaureus and Pseudomonasaeruginosa.
Chemical Industry & Chemical Engineering Quarterly, 2013
The antioxidant and antimicrobial activity of Equisetum arvense L. harvested in a polluted urban ... more The antioxidant and antimicrobial activity of Equisetum arvense L. harvested in a polluted urban area were investigated. The total phenolic content determined by a modified Folin-Ciocalteu method was 335.8 mg of GEA/g of the dried ethanol extract. Antioxidant activity determined by FRAP method was 28.7 mM Fe(II)/g of extract, whereas antioxidant activity index for stable DPPH free radicals was 3.86. The results were compared with control antioxidants (gallic acid, vitamin C, BHA and BHT). Antimicrobial activity was tested by monitoring the impact of different extract concentrations through measuring the change in optical density of bacterial suspension over time and by determining MIC and MBC using macrodilution method. E. arvense extract has been effective on the tested microorganisms depending on the concentration and exposure time. The extract had the strongest antibacterial activity on Staphylococcus aureus, with MIC and MBC of 11.14 mg/mL and 22.28 mg/mL respectively, and the w...
Chemical Industry & Chemical Engineering Quarterly, 2009
This study is a continued investigation of the influence of ferrocene and its derivatives on tryp... more This study is a continued investigation of the influence of ferrocene and its derivatives on trypsin activity. The goal was to examine the effect in vivo, by monitoring the growth of the bacteria Escherichia coli. The growth of the bacteria with the addition of ferrocene and derivatives of various concentrations was followed up spectrophotometrically, measuring changes in OD, correlating OD with the number of formed bacterial colonies and comparing the results as the mean generation time. The obtained results in relation to control experiments indicate a very strong inhibitory action of ferrocene and (dimethylaminomethyl) ferrocene, a medium or modest inhibitory effect of methyl 1'-acetamidoferrocene- 1-carboxylate and benzyl 1'-methoxycarbonyl-1-ferrocenecarbamate; influence of benzyl 1'-carboxy-1-ferrocenecarbamate is negligible, while 1'-acetamidoferrocene-1-carboxylic acid causes the increase in the growth of Escherichia coli.
In this paper, we report surface dielectric and photodielectric properties of low density polyeth... more In this paper, we report surface dielectric and photodielectric properties of low density polyethylene (LDPE)/Emodin composite. Emodin was extracted from Fallopia japonica plant. The composite was obtained from the xylene solution. Dielectric measurements were performed in the frequency range from 240 Hz to 4 kHz and the temperature range from 20 °C – 70 °C. Irradiations of the sample were applied before and during measurement with selected wavelengths from UV to the visible range. Surface dielectric conductance and susceptance of the LDPE/Emodin composite is higher then value of conductance and susceptance of pure LDPE. We found an increase, by one order of magnitude, in conductance and susceptance of the LDPE/Emodin composite with increase of measurement frequency. Furthermore, the surface conductance and susceptance increase due to UV radiation in mentioned temperature range, but during visible radiation at frequency 1 kHz (except in the case green LED lamp) we observed the enhan...
Macedonian Journal of Chemistry and Chemical Engineering
The contents of polyphenolic components (total polyphenols, flavonoids, and monomeric anthocyanin... more The contents of polyphenolic components (total polyphenols, flavonoids, and monomeric anthocyanins) and vitamin C, and the bioactive potential (antioxidant, antiproliferative, and antihyperglycemic activities) of wild cornelian cherry were determined. Samples were collected from four different locations in Bosnia and Herzegovina. Sample CC3 from Drinić had the highest monomeric anthocyanin content (1.40 mg CyGE/g FW) and the highest inhibition of free radicals (IC50 DPPH = 262.19 mg/ml; IC50 ABTS = 76.78 mg/ml; IC50 OH˙ = 102.31 mg/ml) and inhibition of breast adenocarcinoma cell line growth (IC50 MCF-7 = 1.37 mg/ml). Sample CC4 from Drvar showed the highest total polyphenol (55.92 mg GAE/g DW) and vitamin C (88.74 mg/g FW) contents. Sample CC4 significantly inhibited the growth of cervix epithelioid carcinoma (IC50 HeLa = 0.62 mg/ml) and lung adenocarcinoma (IC50 A549 = 0.48 mg/ml) cell lines, and αglucosidase (IC50 AGHA = 0.466 mg/ml). Wild cornelian cherry could be used as a functional food with beneficial pro-health properties.
The results of determination of non- enzymatic antioxidant capacity tomato variety “volovsko srce... more The results of determination of non- enzymatic antioxidant capacity tomato variety “volovsko srce” are presented in this paper. Content of total phenols is between 88.81 to 138.44 µgGAE/gFW, total flavonoids from 59.25 to 66.95 µgQc/gFW, and flavonols from 94.49 to 243.47 µgQc/gFW respectively. The content of lycopene in the samples ranged from 136.32 to 600,3 µg/100gFW, while we determined and the content of vitamin C , which is 12.6 to 15.87 mg/100gFW for 3 different sample probes. The results of antioxidant activity of ethanolic extract of tomato variety “volovsko srce” obtained using DPPH and ABTS methods as compared to Trolox equivalent antioxidant capacity are: DPPH ranged from 1.81 to 2.54 µmol Trolox/gFW, for ABTS from 0.19 to 2.23 µmol Trolox/gFW. The results are in agreement with literature data , but it is most likely to some differences due to different ways of breeding samples.Rezultati određivanja neenzimskih antioksidativnih kapaciteta paradajza sorte „Volovsko srce“ ...
In this paper, the antioxidant activity of 3 red wine samples was determined using 1,1- diphenyl-... more In this paper, the antioxidant activity of 3 red wine samples was determined using 1,1- diphenyl-2- picrylhydrazil (DPPH)- radical scavenging assay, 2,2’- azino- bis- (3- ethylbenzothiazoline-6- sulfonic acid) (ABTS) radical scavenging assay, so as Briggs- Raushers oscillatory reactions. Correlation of these antioxidant methods with the total phenol content in these red wine samples was also performed. The total phenol content was found to vary from 1790,67- 3209,97 mgGAE/Lwine. Antioxidant activity determined by DPPH method 15,45- 17,08 mmolTrolox/Lwine, ABTS method 23,21- 24,14 mmolTrolox/Lwine, and Briggs- Raushers oscillatory reactions 1,826- 3,848 mmolTrolox/Lwine respectively. The total phenol content shows signifficant correlation with ABTS method (0,55), and very signifficant correlation with Briggs- Raushers oscillatory reactions (0,99)U ovom radu određena je antioksidativna aktivnost 3 uzorka crvenih vina primjenom gašenja 1,1- difenil- 2- pikrilhidrazil (DPPH)- stabilnog ...
Wealthy chemical composition of peppers with excellent organoleptic properties (taste, color, sme... more Wealthy chemical composition of peppers with excellent organoleptic properties (taste, color, smell) makes it almost indispensable in the daily diet. The subject matter of this paper is hybrid variety of fresh pepper Bibic F1. Content of each component chemical composition: dry matter (5.78%), total ash (0.36%), total acidity (0.13%) and vitamin C (70.4 mg per 100g), was determined by AOAC methods and was in agreement with literature data. Content of some minerals determined by atomic emission spectrometry (ICP-OES). The amount of each element in 100 g of fresh pepper hybrid variety Bibic F1 was: sodium (3.3 mg), potassium (180.2 mg), magnesium (9.8 mg), calcium (12 mg), phosphorus (23.2 mg), iron (0.72 mg), copper (0.04 mg), zinc (0.2 mg) and manganese (0.11 mg). Fresh pepper hybrid variety Bibic F1 is not a significant source of minerals in the diet.Bogat hemijski sastav paprike sa izvanrednim senzornim svojstvima (ukus, boja, miris) čini je gotovo nezamjenjivom u svakodnevnoj ish...
Allium ursinum is a plant, more known as sremus, crijemus, wild or bearded onion. In nutrition it... more Allium ursinum is a plant, more known as sremus, crijemus, wild or bearded onion. In nutrition it is used as a vegetable (salad and spice), and in human medicine, as an auxiliary agent. It is significant due to its nutritional and healing value. Since diet is largely used seasonally and in fresh state, as a salad, it can be a significant source of some nutrients, such as mineral matter, which are of great importance for human health. Considering the polemics about sremus as a "source of health" we decided to analyze content of mineral matter, macro and micro elements in sremus, with four different locations of the northwest part of Repulic of Srpska. Sodium concentrations were determined from 31,065 to 32,905 mg / kg, potassium from 4703.06 to 4803.485mg / kg, calcium from 1532.545 to 1559.095 mg / kg. Microelements included nickel (0.358 to 0.388 mg / kg), cobalt, aluminum. Mineral matter was determined by atomic absorption spectrophotometry ICP OES spectroscopy after wet...
JOURNAL OF ENGINEERING & PROCESSING MANAGEMENT, 2020
The aim of this paper is to develop specification for the production of roasted coffeewith improv... more The aim of this paper is to develop specification for the production of roasted coffeewith improved nutritional quality. In this respect, the influence of different coffeeblends and temperatures of roasting on the antioxidant activity of coffee was examined.Also, the composition of some bioactive components in the analyzed sampleswas determined. Two Arabica coffees of different quality and Robusta coffee wereused for the preparation of coffee blends. Experimentally determined green coffeeblends B1, B2 and B3 were roasted at 167◦C, 171◦C and 175◦C for 25 minutes inorder to establish the effect of roasting temperature on the antioxidant activity andthe content of bioactive components in blends. Based on the results of DPPH andABTS test, coffee blends B3 and B2, roasted at 171◦C, had the highest (P<0.05)antioxidant activity. Those coffee blends had higher content of Robusta coffee thancoffee blend B1. Results of this research can provide opportunities for the developmentof roasted g...
The complexity of ecological conditions in urban areas imposes the plant species need for the dev... more The complexity of ecological conditions in urban areas imposes the plant species need for the development of various biochemical and physiological adaptive strategies. The aim of our research was to examine the antioxidative and antifungal metabolism of species Pinus nigra, Picea omorika, Tilia cordata and Betula pendula from the area of Banja Luka City (urban area) during two vegetation seasons (spring and autumn) and compared with the same species from forest habitats. Changes in the protein concentration, activity and isoenzyme profiles of peroxidases (POD, EC 1.11.1.7), content and antioxidative activity of total phenols and antifungal activity in leaves and needles of the plants from the urban area and forest habitats were monitored. The obtained results indicate that urban areas induce changes in antioxidative metabolism in all examined species, but that the response is species specific. The most sensitive parameter that indicates different adaptation strategy of Pinus nigra, Picea omorika, Tilia cordata and Betula pendula to environment conditions in the urban area were peroxidase isoenzyme patterns. Less specific parameter was phenol content even though there are some indications for role of their antioxidative capacity in the adjustment to specific habitat. In addition, each species had different metabolic strategy to cope with the changes caused by the urban environment.
GLASNIK HEMIČARA, TEHNOLOGA I EKOLOGA REPUBLIKE SRPSKE, 2018
Proteoliza sarkoplazmatičnih i miofibrilarnih proteina je vrlo važna biohemijska pojavakoja se ja... more Proteoliza sarkoplazmatičnih i miofibrilarnih proteina je vrlo važna biohemijska pojavakoja se javlja u toku zrenja fermentisanih proizvoda od mesa. Kao rezultat aktivnostiproteinaza i peptidaza, povećava se sadržaj polipeptida, peptida i slobodnih aminokiselina,koji učestvuju u razvoju mirisa, ukusa i teksture. SDS-PAGE elektroforezom analiziranisu proteinski profili domaćih fermentisanih kobasica sa dodatkom 0,5% i 1,5% izolatasurutke i soje. Pripremom uzoraka razdvojene su sarkoplazmatične i miofibrilarne frakcije.Denzitometrijski su preračunate molekulske mase proteina. Praćene su kvalitativnepromjene proteina nadjeva, kobasica nakon zrenja i tokom šestomjesečnog čuvanjavakuum pakovanih uzoraka na temperaturi od +4°C.Biohemijske promene, u osnovi, se malo razlikuju. Dinamika promjene elektroforetskihprofila sarkoplazmatičnih i miofibrilarnih proteina, pokazuju veoma slične tendencije.Elektroforetska slika miofibrilarnih proteina nadjeva prije punjenja u crijeva nam pokazujeda su...
Acta Scientiarum Polonorum Technologia Alimentaria, 2016
Background. Coff ee is one of the most widely consumed beverages in the world, because of its uni... more Background. Coff ee is one of the most widely consumed beverages in the world, because of its unique sensory properties and physiological properties. Coff ee beverages represent a signifi cant source of antioxidants in the consumers' diet and contribute signifi cantly to their daily intake. The aim of this research was to investigate the eff ect of diff erent roasting degrees on the content of biologically active compounds and antioxidant activity in diff erent quality classes of Arabica coff ee. Materials and methods. Samples of green Arabica coff ee (Rio Minas) of two quality classes from two production batches were used for the research. Roasting was carried out at temperatures of 167, 175 and 171°C. The total phenol content (TPC), total fl avonoid content (TFC), fl avonol content (FC) and antioxidant activity (DPPH, ABTS) in the coff ee extracts was determined. Results. This research shows that TPC was signifi cantly higher (P < 0.05) in green coff ee compared to TPC in roasted coff ee, and TPC decreases as the roasting temperature increases. TFC and FC were signifi cantly lower (P < 0.05) in green coff ee than in roasted coff ee. Diff erences in TPC between the 1 st and 2 nd classes of Arabica coff ee were not signifi cant (P > 0.05), while diff erences in TFC were signifi cant (P < 0.05) only for green coff ee from the second production batch and diff erences in FC were signifi cant (P < 0.05) for green coffee and for coff ee roasted at 175°C. Roasting temperatures have diff erent infl uences the antioxidant activity (DPPH, ABTS) of coff ee and the highest antioxidant activity was determined in coff ee roasted at 171°C. An exception was 1 st class Arabica coff ee roasted at 167°C (ABTS). All samples of 1 st class Arabica coff ee had higher antioxidant activity (DPPH, ABTS) compared to 2 nd class Arabica. Conclusions. This research shows that the bioactive compounds content and antioxidant activity of diff erent quality classes of Arabica coff ee are dependent on the degree of roasting. TPC decreases when the roasting temperature increases, while TFC and FC also increase. These results indicate that the antioxidant activity of coff ee depends on a variety of bioactive components in coff ee beans. Antioxidant activity largely depends on the class of coff ee. The coff ee samples of 1 st class quality (maximum 8 black beans/300 g from the sample and large bean size) had higher antioxidant activity compared to samples of 2 nd quality class (maximum 19 black beans/300 g in the sample and medium-sized beans).
Ethanolic (50%, v/v) extract of Reynoutria japonica Houtt. rhizome from the Banja Luka region was... more Ethanolic (50%, v/v) extract of Reynoutria japonica Houtt. rhizome from the Banja Luka region was prepared. The dry extract was dissolved in methanol, and total phenols content, antimicrobial and antioxidative activities were determined. The total phenols content was determined using modified Folin-Ciocalteu method, the antimicrobial activity by monitoring the optical density, and antioxidative activity by the method of quenching stable free 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals by FRAP and ABTS metods. The antioxidative activity results were compared with control antioxidants: vitamin C, BHA and BHT. In order to determine the antimicrobial extract activity, E. coli, S. aureus and B. cereus were used as test microorganisms. The paper discusses the results of antimicrobial and antioxidative activeties of the R. japonica extract with respect to extract concentration as well as to total phenols content. The extract of R. japonica rhizome shows both, a significant overall antiox...
Samples of stinging nettle or common nettle (Urtica dioica L.) were collected from the area of Ba... more Samples of stinging nettle or common nettle (Urtica dioica L.) were collected from the area of Banja Luka. To measure and evaluate the content of chlorophyll (a and b), carotenoids, and soluble proteins, as well as peroxidase activity (POD, EC 1.11.1.7.), fresh nettle leaves of different developmental stages were used. Dried nettle leaves were used to obtain ethanol extract. The dry residue of ethanol extract was dissolved in methanol and the obtained solution was used to determine the content of total phenols, flavonoids, flavonols, as well as non-enzymatic antioxidant activity and antimicrobial activity. The non-enzymatic antioxidant activity was determined by different methods: FRAP, DPPH, and ABTS. The results were compared to those of standard substances like vitamin C, BHT, and BHA. Antimicrobial activity was screened by using macrodilution method. The obtained results showed insignificantly higher content of chlorophyll, carotenoids, and proteins in young nettle leaves as wel...
The aim of this study was the determination of the antioxidant and antihyperglyce-mic effect of w... more The aim of this study was the determination of the antioxidant and antihyperglyce-mic effect of wild grown rosehip and pomegranate fruit extracts, and the determination of the polyphenolic content (total phenols, flavonoids, flavonols, flavan-3-ols and total and monomeric anthocyanins). The antioxidant activity of rosehip fruit in view of stable DPPH and ABTS radicals was higher comparing to pomegranate fruit, while according to the OH radical these two samples showed a similar effect (94.17 and 92.03 mg/mL). A dry rosehip fruit extract was found to have a 1.6 times more pronounced antihyperglycemic activity (1.42 mg/mL) compared to the dried pomegranate fruit extract (2.26 mg/mL). The content of total phenols of rosehip fruit was 8.75 mg GAE/g FPM and 22.01 mg GAE/g DPM , higher than the content of total phenols of pomegranate fruit (3.44 mg GAE/g FPM and 15.43 mg GAE/g DPM). The content of total phenols in rosehip and pomegranate fruits was higher than the content of total flavono...
The isolation, chemical and microbiological characterization of essential oils originate from tob... more The isolation, chemical and microbiological characterization of essential oils originate from tobacco dust where performed. The main source of subjected tobacco dust was technological process of Tobacco Factory Banja Luka. In extracted essential oils 25 components where identified. Simultaneousl\ , in the petrol ether extract where identified 31 component. The main compounds of extracted essential oils are Neophytadiene and Solanone. The main compounds of petro: ether extract are Nicotine, Neophytadiene, Sorbitol and Neodihydrocarveole. The microbiological activity examination was showed significant antibacterial affection of extracted essential oils and petrol ether ex ract on Escherichia coli, Staphylococcusaureus and Pseudomonasaeruginosa.
Chemical Industry & Chemical Engineering Quarterly, 2013
The antioxidant and antimicrobial activity of Equisetum arvense L. harvested in a polluted urban ... more The antioxidant and antimicrobial activity of Equisetum arvense L. harvested in a polluted urban area were investigated. The total phenolic content determined by a modified Folin-Ciocalteu method was 335.8 mg of GEA/g of the dried ethanol extract. Antioxidant activity determined by FRAP method was 28.7 mM Fe(II)/g of extract, whereas antioxidant activity index for stable DPPH free radicals was 3.86. The results were compared with control antioxidants (gallic acid, vitamin C, BHA and BHT). Antimicrobial activity was tested by monitoring the impact of different extract concentrations through measuring the change in optical density of bacterial suspension over time and by determining MIC and MBC using macrodilution method. E. arvense extract has been effective on the tested microorganisms depending on the concentration and exposure time. The extract had the strongest antibacterial activity on Staphylococcus aureus, with MIC and MBC of 11.14 mg/mL and 22.28 mg/mL respectively, and the w...
Chemical Industry & Chemical Engineering Quarterly, 2009
This study is a continued investigation of the influence of ferrocene and its derivatives on tryp... more This study is a continued investigation of the influence of ferrocene and its derivatives on trypsin activity. The goal was to examine the effect in vivo, by monitoring the growth of the bacteria Escherichia coli. The growth of the bacteria with the addition of ferrocene and derivatives of various concentrations was followed up spectrophotometrically, measuring changes in OD, correlating OD with the number of formed bacterial colonies and comparing the results as the mean generation time. The obtained results in relation to control experiments indicate a very strong inhibitory action of ferrocene and (dimethylaminomethyl) ferrocene, a medium or modest inhibitory effect of methyl 1'-acetamidoferrocene- 1-carboxylate and benzyl 1'-methoxycarbonyl-1-ferrocenecarbamate; influence of benzyl 1'-carboxy-1-ferrocenecarbamate is negligible, while 1'-acetamidoferrocene-1-carboxylic acid causes the increase in the growth of Escherichia coli.
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Papers by Zoran Kukric