In plant biochemistry and physiology, coumarins are known as antioxidants, enzyme inhibitors and precursors of toxic substances. Nuclear magnetic resonance (NMR) spectra are primary sources of molecular structural data. NMR provides detailed information about the local environment of the atom which can be used to determine the atomic connectivity, stereochemistry, and molecular conformation. For many years the molecular structure has been determined by NMR spectroscopy and chemical shifts are determined manually with the help of computer programs. However, recent progress in computational chemistry and chemo/bioinformatics opened the possibility for the prediction of chemical shifts (especially those of 1H and 13C nuclei) of new chemicals. We analyzed the accuracy of three available chemoinformatics methods developed for the prediction of 1H and 13C chemical shifts based on deep neural networks CASCADE [1], an older prediction method based on classical neural networks NMRshiftDB [2,3], and group-contribution method in ChemDraw [4]. The mean absolute errors (MAEs) in the prediction of NMR shifts of four newly synthesized coumarins [5] by CASCADE, NMRshiftDB and ChemDraw are (respectively) 0.39, 0.65 and 0.32 ppm for 1H, and 1.5, 6.5 and 2.3 ppm for 13C atoms, shoving relatively big differences between these prediction methods.
{"title":"THE PREDICTION ACCURACY OF 1H AND 13C NMR CHEMICAL SHIFTS OF COUMARIN DERIVATIVES BY CHEMO/BIOINFORMATICS METHODS","authors":"D. Bešlo, M. Molnár, D. Agić, S. Roca, B. Lučić","doi":"10.46793/iccbi21.422b","DOIUrl":"https://doi.org/10.46793/iccbi21.422b","url":null,"abstract":"In plant biochemistry and physiology, coumarins are known as antioxidants, enzyme inhibitors and precursors of toxic substances. Nuclear magnetic resonance (NMR) spectra are primary sources of molecular structural data. NMR provides detailed information about the local environment of the atom which can be used to determine the atomic connectivity, stereochemistry, and molecular conformation. For many years the molecular structure has been determined by NMR spectroscopy and chemical shifts are determined manually with the help of computer programs. However, recent progress in computational chemistry and chemo/bioinformatics opened the possibility for the prediction of chemical shifts (especially those of 1H and 13C nuclei) of new chemicals. We analyzed the accuracy of three available chemoinformatics methods developed for the prediction of 1H and 13C chemical shifts based on deep neural networks CASCADE [1], an older prediction method based on classical neural networks NMRshiftDB [2,3], and group-contribution method in ChemDraw [4]. The mean absolute errors (MAEs) in the prediction of NMR shifts of four newly synthesized coumarins [5] by CASCADE, NMRshiftDB and ChemDraw are (respectively) 0.39, 0.65 and 0.32 ppm for 1H, and 1.5, 6.5 and 2.3 ppm for 13C atoms, shoving relatively big differences between these prediction methods.","PeriodicalId":9171,"journal":{"name":"Book of Proceedings: 1st International Conference on Chemo and BioInformatics,","volume":"74 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75990627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bacterial biofilm is a complex community of bacterial cells enclosed in a polymer matrix and attached to a biotic or abiotic substrate. In this living form the bacteria are more resistant to antimicrobial agents than in the form of planktonic cells. Biofilm is a common cause of chronic infections in humans, so due to the growing resistance to antibiotics, alternative methods for controlling infections using medicinal plants have been proposed. In this study, the antibiofilm activity of ethanol and acetone extracts of plants Lamium album, Achillea millefolium and Agrimonia eupatoria against eight clinical isolates of human pathogenic bacteria was examined. Inhibition of biofilm formation was demonstrated using the crystal violet test and the effect on metabolic activity was confirmed by the use of resazurin dye test. Ethanol extract of L. album showed the greatest activity against P. aeruginosa (PA9) at a concentration of 20 mg/ml (> 80% of inhibition), while acetone extract acted at a concentration of 5 mg/ml (≥ 18%) against Klebsiella sp. (K9). At a concentration of 10 mg/ml, the ethanol extract of A. millefolium was effective against E. coli (E16) and P. aeruginosa (PA8) (> 70%), while the acetone extract was effective at 2.5 mg/ml (> 80%) against E. coli (E16). Ethanol and acetone extracts of A. eupatoria were effective at a concentration of 10 mg/ml (> 50%) against E. coli (E16). The antibiofilm activity of the tested plant extracts on certain clinical isolates indicates their great potential in the treatment of infections caused by biofilm-producing bacteria.
{"title":"ANTIBIOFILM ACTIVITY OF SELECTED PLANT SPECIES","authors":"Jelena N. Terzić, M. Stanković, O. Stefanović","doi":"10.46793/iccbi21.280t","DOIUrl":"https://doi.org/10.46793/iccbi21.280t","url":null,"abstract":"Bacterial biofilm is a complex community of bacterial cells enclosed in a polymer matrix and attached to a biotic or abiotic substrate. In this living form the bacteria are more resistant to antimicrobial agents than in the form of planktonic cells. Biofilm is a common cause of chronic infections in humans, so due to the growing resistance to antibiotics, alternative methods for controlling infections using medicinal plants have been proposed. In this study, the antibiofilm activity of ethanol and acetone extracts of plants Lamium album, Achillea millefolium and Agrimonia eupatoria against eight clinical isolates of human pathogenic bacteria was examined. Inhibition of biofilm formation was demonstrated using the crystal violet test and the effect on metabolic activity was confirmed by the use of resazurin dye test. Ethanol extract of L. album showed the greatest activity against P. aeruginosa (PA9) at a concentration of 20 mg/ml (> 80% of inhibition), while acetone extract acted at a concentration of 5 mg/ml (≥ 18%) against Klebsiella sp. (K9). At a concentration of 10 mg/ml, the ethanol extract of A. millefolium was effective against E. coli (E16) and P. aeruginosa (PA8) (> 70%), while the acetone extract was effective at 2.5 mg/ml (> 80%) against E. coli (E16). Ethanol and acetone extracts of A. eupatoria were effective at a concentration of 10 mg/ml (> 50%) against E. coli (E16). The antibiofilm activity of the tested plant extracts on certain clinical isolates indicates their great potential in the treatment of infections caused by biofilm-producing bacteria.","PeriodicalId":9171,"journal":{"name":"Book of Proceedings: 1st International Conference on Chemo and BioInformatics,","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76820306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ana Rilak Simović, D. Lazić, Milica Međedović, D. Ćoćić, B. Petrović
We synthesized and characterized the ruthenium(III) pincer-type complex [RuCl3(H2Lt-Bu] (H2Lt- Bu = 2,6-bis(5-tert-butyl-1H-pyrazol-3-yl)pyridine, 1) by elemental analysis, IR and UV-Vis spectroscopy, and mass spectrometry (MS) method ESI Q-TOF. For comparison reason, we also studied ruthenium(III) terpyridine complexes of the general formula [Ru(N-N-N)Cl3] where N-N-N = 4′-chloro- terpyridine (Cl-tpy; 2) or 4′-chlorophenyl-terpyridine (Cl-Ph-tpy; 3). Kinetic study of the substitution reactions of 1–3 with biomolecules showed that the rate constants depend on the properties of the spectator ligand and the nature of the entering nucleophile. To gain further insight into the reactivity of ruthenium complexes with potential biological targets, we examined the interactions of 1 – 3 with DNA and HSA. The DNA/HSA binding study showed that in comparison to complex 1 (bis– pyrazolylpyridine), the other two (2 and 3) terpyridine complexes had a slightly better binding affinity to calf thymus DNA (CT DNA), while in the case of human serum albumin (HSA), complex 1 exhibited the most strong quenching ability.
{"title":"SYNTHESIS AND BIOLOGICAL ACTIVITY OF THE NEW PINCER TYPE RUTHENIUM(III) COMPLEX","authors":"Ana Rilak Simović, D. Lazić, Milica Međedović, D. Ćoćić, B. Petrović","doi":"10.46793/iccbi21.316rs","DOIUrl":"https://doi.org/10.46793/iccbi21.316rs","url":null,"abstract":"We synthesized and characterized the ruthenium(III) pincer-type complex [RuCl3(H2Lt-Bu] (H2Lt- Bu = 2,6-bis(5-tert-butyl-1H-pyrazol-3-yl)pyridine, 1) by elemental analysis, IR and UV-Vis spectroscopy, and mass spectrometry (MS) method ESI Q-TOF. For comparison reason, we also studied ruthenium(III) terpyridine complexes of the general formula [Ru(N-N-N)Cl3] where N-N-N = 4′-chloro- terpyridine (Cl-tpy; 2) or 4′-chlorophenyl-terpyridine (Cl-Ph-tpy; 3). Kinetic study of the substitution reactions of 1–3 with biomolecules showed that the rate constants depend on the properties of the spectator ligand and the nature of the entering nucleophile. To gain further insight into the reactivity of ruthenium complexes with potential biological targets, we examined the interactions of 1 – 3 with DNA and HSA. The DNA/HSA binding study showed that in comparison to complex 1 (bis– pyrazolylpyridine), the other two (2 and 3) terpyridine complexes had a slightly better binding affinity to calf thymus DNA (CT DNA), while in the case of human serum albumin (HSA), complex 1 exhibited the most strong quenching ability.","PeriodicalId":9171,"journal":{"name":"Book of Proceedings: 1st International Conference on Chemo and BioInformatics,","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90656157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Plants from the genus Scrophularia, family Scrophulariaceae have numerous biological activities such as antibacterial, antioxidant, antiprotozoal, antitumor, hepatoprotective, and antidiabetic. However, as far as we know, genotoxic and antigenotoxic effects of these two plant species remain unexplored. The present study aimed to evaluate possible in vivo protective effects of the methanol extracts of two plant species of the Scrophularia genus, Scrophularia canina L. and S. alata Gilib., against carbon tetrachloride (CCl4)-induced DNA damage in albino Wistar rat. A significant increase in total comet score has been shown in animals receiving CCl4 compared with the negative control. Treatment with either S. alata or S. canina extracts reduced CCl4 induced DNA damage as indicated by the percentage of reduction in total comet score with a value above 50%.
{"title":"DNA PROTECTIVE ACTIVITY OF TWO SPECIES OF THE „SCROPHULARIA“ GENUS 2021ICCBIKG (2021)","authors":"S. Matić, P. Mašković, Katarina Šipovac","doi":"10.46793/iccbi21.218m","DOIUrl":"https://doi.org/10.46793/iccbi21.218m","url":null,"abstract":"Plants from the genus Scrophularia, family Scrophulariaceae have numerous biological activities such as antibacterial, antioxidant, antiprotozoal, antitumor, hepatoprotective, and antidiabetic. However, as far as we know, genotoxic and antigenotoxic effects of these two plant species remain unexplored. The present study aimed to evaluate possible in vivo protective effects of the methanol extracts of two plant species of the Scrophularia genus, Scrophularia canina L. and S. alata Gilib., against carbon tetrachloride (CCl4)-induced DNA damage in albino Wistar rat. A significant increase in total comet score has been shown in animals receiving CCl4 compared with the negative control. Treatment with either S. alata or S. canina extracts reduced CCl4 induced DNA damage as indicated by the percentage of reduction in total comet score with a value above 50%.","PeriodicalId":9171,"journal":{"name":"Book of Proceedings: 1st International Conference on Chemo and BioInformatics,","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91185210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nevena Milivojević, D. Caballero, M. Carvalho, M. Zivanovic, N. Filipovic, Rui R Reis, J. Oliveira
Further technological advances are in great need for improving our understanding about critical biological and fundamental pathological processes, such as tissue development and cancer progression, or for the discovery and screening of novel pharmacological drugs. Preclinical experimentation demands for highly reliable and physiologically-relevant systems capable of recapitulating the complex human physiology. Traditional in vitro models, albeit widely employed, fail to reproduce the complexity of the native scenario with cells displaying aberrant gene expressions. Similarly, in vivo animal models, such as mice, poorly mimic the human condition and are ethically questionable. During the last decades, a new paradigm in preclinical modelling has emerged aiming to solve the limitations of the aforementioned methods. The combination of advanced tissue engineering, nanotechnology, and cell biology has resulted in the development of cutting-edge microfluidics-based models with an unprecedented ability to recreate within a microfluidic device the native habitat of cells within a microengineered chip. A diverse variety of micro- and bio-fabrication techniques is available for the development of microfluidic devices. Among all them, UV-photolithography and soft lithography is the considered the gold-standard method for the fabrication of chips due to its simplicity, versatility, and rapid prototyping. In this work, we describe the step-by-step fabrication procedure of a microfluidic chip by UV-photolithography and replica molding and discuss about their potential applications in the biomedical field.
{"title":"ENGINEERING A MICROFLUDIC PLATFORM AS A PRE-CLINICAL MODEL FOR BIOMEDICAL APPLICATIONS","authors":"Nevena Milivojević, D. Caballero, M. Carvalho, M. Zivanovic, N. Filipovic, Rui R Reis, J. Oliveira","doi":"10.46793/iccbi21.259m","DOIUrl":"https://doi.org/10.46793/iccbi21.259m","url":null,"abstract":"Further technological advances are in great need for improving our understanding about critical biological and fundamental pathological processes, such as tissue development and cancer progression, or for the discovery and screening of novel pharmacological drugs. Preclinical experimentation demands for highly reliable and physiologically-relevant systems capable of recapitulating the complex human physiology. Traditional in vitro models, albeit widely employed, fail to reproduce the complexity of the native scenario with cells displaying aberrant gene expressions. Similarly, in vivo animal models, such as mice, poorly mimic the human condition and are ethically questionable. During the last decades, a new paradigm in preclinical modelling has emerged aiming to solve the limitations of the aforementioned methods. The combination of advanced tissue engineering, nanotechnology, and cell biology has resulted in the development of cutting-edge microfluidics-based models with an unprecedented ability to recreate within a microfluidic device the native habitat of cells within a microengineered chip. A diverse variety of micro- and bio-fabrication techniques is available for the development of microfluidic devices. Among all them, UV-photolithography and soft lithography is the considered the gold-standard method for the fabrication of chips due to its simplicity, versatility, and rapid prototyping. In this work, we describe the step-by-step fabrication procedure of a microfluidic chip by UV-photolithography and replica molding and discuss about their potential applications in the biomedical field.","PeriodicalId":9171,"journal":{"name":"Book of Proceedings: 1st International Conference on Chemo and BioInformatics,","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85072492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The discovery that palladium complexes possess a wide range of biological activities (from antitumor, -viral, -malarial, -fungal to antimicrobial activities) encourages further research in this scientific field. Herein we describe the synthesis and characterization of a novel palladium (II) complex, using [Pd(dien)Cl]Cl and 2-(azidomethyl)cyclopropane-1,1-dicarboxylic acid (azmcpda) as a ligand. [Pd(dien)Cl]Cl was selected as a starting material taking into consideration its importance as a model for the investigation of the substitution reactions in coordination chemistry and a deeper understanding of the biological activities of some structurally similar compounds. The ligand compound was synthesized by the procedure described in the literature. It is noteworthy to mention that 2- (azidomethyl)cyclopropane-1,1-dicarboxylic acid presents the precursor for the synthesis of 2- (aminomethyl)cyclopropane-1,1-dicarboxylic acid, as an example of the constrained γ-amino dicarboxylic acids. The synthesis was achieved by the conversion of the ligand compound into the corresponding sodium dicarboxylate salt and subsequent treatment with [Pd(dien)Cl]Cl (pH maintained between 6-7). The IR and NMR spectra, as well as elemental analysis have confirmed that the Na[Pd(dien)(azmcpda)]. H2O species was formed and that coordination of the ligand compound to the metal ion was established through carboxylate oxygen donor atom.
{"title":"SYNTHESIS AND CHARACTERIZATION OF PALLADIUM (II)–2- (AZIDOMETHYL)CYCLOPROPANE-1,1-DICARBOXYLIC ACID COMPLEX","authors":"M. Kostić, V. Divac, Sven Mangelinckx","doi":"10.46793/iccbi21.297k","DOIUrl":"https://doi.org/10.46793/iccbi21.297k","url":null,"abstract":"The discovery that palladium complexes possess a wide range of biological activities (from antitumor, -viral, -malarial, -fungal to antimicrobial activities) encourages further research in this scientific field. Herein we describe the synthesis and characterization of a novel palladium (II) complex, using [Pd(dien)Cl]Cl and 2-(azidomethyl)cyclopropane-1,1-dicarboxylic acid (azmcpda) as a ligand. [Pd(dien)Cl]Cl was selected as a starting material taking into consideration its importance as a model for the investigation of the substitution reactions in coordination chemistry and a deeper understanding of the biological activities of some structurally similar compounds. The ligand compound was synthesized by the procedure described in the literature. It is noteworthy to mention that 2- (azidomethyl)cyclopropane-1,1-dicarboxylic acid presents the precursor for the synthesis of 2- (aminomethyl)cyclopropane-1,1-dicarboxylic acid, as an example of the constrained γ-amino dicarboxylic acids. The synthesis was achieved by the conversion of the ligand compound into the corresponding sodium dicarboxylate salt and subsequent treatment with [Pd(dien)Cl]Cl (pH maintained between 6-7). The IR and NMR spectra, as well as elemental analysis have confirmed that the Na[Pd(dien)(azmcpda)]. H2O species was formed and that coordination of the ligand compound to the metal ion was established through carboxylate oxygen donor atom.","PeriodicalId":9171,"journal":{"name":"Book of Proceedings: 1st International Conference on Chemo and BioInformatics,","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85116796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nikola Ristivojević, D. Dimić, Marko Đošić, Stefan Mišić, Anđela Gavran, Jelena Đorović Jovanović, Jasmina M. Dimitrić Marković
Anabolic steroids are a group of commonly counterfeit substances used by individuals who want to gain weight and muscles. Testosterone propionate (TP), an ester analog of testosterone, belongs to this group and its spectroscopic analysis is important especially when it is improperly labeled and misused. In this contribution quantum chemical methods, at the B3LYP/6- 311++G(d,p) level of theory, were applied for the prediction of the vibrational (IR and Raman) and UV-VIS spectra of TP. The applicability of the chosen level of theory was proven based on the comparison between experimental and theoretical bond lengths and angles. The most prominent bands in the IR and Raman spectra were assigned and correlated with the calculated ones. The electronic spectra were also analyzed and the assignments were made based on the Time-Dependent Density Functional Theory (TD-DFT) calculations. The orbitals included in the most intense transitions were visualized and possible solvent effects were discussed. The presented results proved the applicability of the DFT methods for the prediction of spectra that could lead to the counterfeit substances determination.
{"title":"SPECTROSCOPIC AND QUANTUM-CHEMICAL INVESTIGATION OF TESTOSTERONE PROPIONATE, A COMMONLY MISUSED ANABOLIC STEROID","authors":"Nikola Ristivojević, D. Dimić, Marko Đošić, Stefan Mišić, Anđela Gavran, Jelena Đorović Jovanović, Jasmina M. Dimitrić Marković","doi":"10.46793/iccbi21.450r","DOIUrl":"https://doi.org/10.46793/iccbi21.450r","url":null,"abstract":"Anabolic steroids are a group of commonly counterfeit substances used by individuals who want to gain weight and muscles. Testosterone propionate (TP), an ester analog of testosterone, belongs to this group and its spectroscopic analysis is important especially when it is improperly labeled and misused. In this contribution quantum chemical methods, at the B3LYP/6- 311++G(d,p) level of theory, were applied for the prediction of the vibrational (IR and Raman) and UV-VIS spectra of TP. The applicability of the chosen level of theory was proven based on the comparison between experimental and theoretical bond lengths and angles. The most prominent bands in the IR and Raman spectra were assigned and correlated with the calculated ones. The electronic spectra were also analyzed and the assignments were made based on the Time-Dependent Density Functional Theory (TD-DFT) calculations. The orbitals included in the most intense transitions were visualized and possible solvent effects were discussed. The presented results proved the applicability of the DFT methods for the prediction of spectra that could lead to the counterfeit substances determination.","PeriodicalId":9171,"journal":{"name":"Book of Proceedings: 1st International Conference on Chemo and BioInformatics,","volume":"79 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84089759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sonja Stojanov, M. Jovičić, I. Bobinac, Olga M. Govedarica, J. Pavličević, Julijana Blagojević, Dragan D. Govedarica, O. Bera
This paper aims to investigate the effect of the addition of mineral oil and pyrolytic carbon black on crosslinking the natural rubber and the mechanical properties of the crosslinked products. A rheometer determined curing characteristics at a temperature of 150 °C. The mechanical properties of prepared vulcanized composites were determined. By adding mineral oil to rubber compounds, the vulcanization reaction starts later, and it takes slightly more time to achieve the optimal vulcanization time. The addition of mineral oil to the rubber mixture achieves better dispersion of pyrolytic carbon blacks in the matrix and thus increases the physical interaction between the filler and rubber. Pyrolytic carbon black (pCB) is obtained by recycling waste products and contains a higher proportion of impurities. Due to impurities, PCB has a smaller surface area for the physical adsorption of rubber molecules than standard carbon black, and it can be assumed that this has led to a decrease in the crosslinking density. The addition of mineral oil to rubber compounds results in a slight reduction in mechanical properties. The type of carbon black has a much more significant influence on the mechanical properties of vulcanized composites based on natural rubber.
{"title":"RHEOLOGICAL BEHAVIOR AND MECHANICAL PROPERTIES OF RUBBER COMPOSITES BASED ON NATURAL RUBBER LOADED WITH MINERAL OILS AND PYROLYTIC CARBON BLACK","authors":"Sonja Stojanov, M. Jovičić, I. Bobinac, Olga M. Govedarica, J. Pavličević, Julijana Blagojević, Dragan D. Govedarica, O. Bera","doi":"10.46793/iccbi21.173s","DOIUrl":"https://doi.org/10.46793/iccbi21.173s","url":null,"abstract":"This paper aims to investigate the effect of the addition of mineral oil and pyrolytic carbon black on crosslinking the natural rubber and the mechanical properties of the crosslinked products. A rheometer determined curing characteristics at a temperature of 150 °C. The mechanical properties of prepared vulcanized composites were determined. By adding mineral oil to rubber compounds, the vulcanization reaction starts later, and it takes slightly more time to achieve the optimal vulcanization time. The addition of mineral oil to the rubber mixture achieves better dispersion of pyrolytic carbon blacks in the matrix and thus increases the physical interaction between the filler and rubber. Pyrolytic carbon black (pCB) is obtained by recycling waste products and contains a higher proportion of impurities. Due to impurities, PCB has a smaller surface area for the physical adsorption of rubber molecules than standard carbon black, and it can be assumed that this has led to a decrease in the crosslinking density. The addition of mineral oil to rubber compounds results in a slight reduction in mechanical properties. The type of carbon black has a much more significant influence on the mechanical properties of vulcanized composites based on natural rubber.","PeriodicalId":9171,"journal":{"name":"Book of Proceedings: 1st International Conference on Chemo and BioInformatics,","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88152786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Stanić, N. Vukićević, V. Cvetković, M. Pavlovic, S. Dimitrijević, Biljana M Šmit
Four 2-thiohydantoin derivatives were synthesized and their corrosion inhibition properties on mild steel (MS) in 0.5M HCl solution was evaluated using usual gravimetric and electrochemical methods (weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS). Morphology of the metal surface was characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The study has shown that these compounds provide good protection for mild steel against corrosion in the acidic medium.
{"title":"ELECTROCHEMICAL INVESTIGATION OF 2-THIOHYDANTOIN DERIVATIVES AS CORROSION INHIBITORS FOR MILD STEEL IN ACIDIC MEDIUM","authors":"P. Stanić, N. Vukićević, V. Cvetković, M. Pavlovic, S. Dimitrijević, Biljana M Šmit","doi":"10.46793/iccbi21.157s","DOIUrl":"https://doi.org/10.46793/iccbi21.157s","url":null,"abstract":"Four 2-thiohydantoin derivatives were synthesized and their corrosion inhibition properties on mild steel (MS) in 0.5M HCl solution was evaluated using usual gravimetric and electrochemical methods (weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS). Morphology of the metal surface was characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The study has shown that these compounds provide good protection for mild steel against corrosion in the acidic medium.","PeriodicalId":9171,"journal":{"name":"Book of Proceedings: 1st International Conference on Chemo and BioInformatics,","volume":"110 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86277721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jovica Branković, V. Milovanović, Z. Petrović, V. Petrović
Gallic hydrazones, as gallic acid derivatives, are known as pharmacophores of numerous multipotent agents. Among them, antiproliferative activity is one of the most important. On the other hand, thioredoxin reductase (TrxR1) is a part of the thioredoxin system, one of the most important systems responsible for maintaining the redox equilibrium inside the cell. It is overexpressed in different forms of tumors. Bearing this in mind, TrxR1 is a valid target for the development of compounds with potential antiproliferative activity. For this purpose, eight gallic acid-based hydrazones are selected and examined in silico for their potential inhibitory activity towards TrxR1.
{"title":"GALLIC ACID HYDRAZONES: ‘IN SILICO’ INHIBITION OF THIOREDOXIN REDUCTASE","authors":"Jovica Branković, V. Milovanović, Z. Petrović, V. Petrović","doi":"10.46793/iccbi21.320b","DOIUrl":"https://doi.org/10.46793/iccbi21.320b","url":null,"abstract":"Gallic hydrazones, as gallic acid derivatives, are known as pharmacophores of numerous multipotent agents. Among them, antiproliferative activity is one of the most important. On the other hand, thioredoxin reductase (TrxR1) is a part of the thioredoxin system, one of the most important systems responsible for maintaining the redox equilibrium inside the cell. It is overexpressed in different forms of tumors. Bearing this in mind, TrxR1 is a valid target for the development of compounds with potential antiproliferative activity. For this purpose, eight gallic acid-based hydrazones are selected and examined in silico for their potential inhibitory activity towards TrxR1.","PeriodicalId":9171,"journal":{"name":"Book of Proceedings: 1st International Conference on Chemo and BioInformatics,","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89156681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：