Journal of Chemical Technology and Metallurgy最新文献

{"title":"SYNTHESIS AND ANTIOXIDANT ACTIVITY OF SOME AMINOADAMANTANE DERIVATIVES","authors":"Antoniya Stoymirska, R. Chayrov, A. Georgieva, E. Tsvetanova, A. Alexandrova, I. Stankova","doi":"10.59957/jctm.v59.i4.2024.15","DOIUrl":"https://doi.org/10.59957/jctm.v59.i4.2024.15","url":null,"abstract":"Chronic fatigue syndrome (CFS) and neurocognitive deficits are a major problem of modern society. The etiology of CFS remains unclear, however, a large number of recent studies have shown oxidative stress may be involved in its pathogenesis. Fatigue is frequent and important in the lives of Parkinson’s disease (PD) patients. 1-amino-adamantane (amantadine and memantine) derivatives has been proposed to be useful in the treatment of Parkinson’s and Alzheimer’s diseases. Its beneficial effect has been related to its novel properties as an N-methyl-D-aspartate receptor (NMDAR) blocker which can neutralize the effect of glutamate at striatal and subthalamic levels. We synthesized and evaluated the antioxidant activity of eleven new aminoadamantane derivatives. Their antioxidant activity has been evaluated using different (superoxide anion, hydroxyl) radical generating systems. The compoundwith s highest anti-oxidative capacity contain 2-(Benzhydrylsulfinyl) substituent.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":" 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141675226","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}

{"title":"STRUCTURAL REQUIREMENTS OF ANGIOTENSIN RECEPTOR: PREFERRED MODIFICATIONS FOR ANTAGONIST DESIGN","authors":"T. Dzimbova, Atanas Chapkanov","doi":"10.59957/jctm.v59.i4.2024.16","DOIUrl":"https://doi.org/10.59957/jctm.v59.i4.2024.16","url":null,"abstract":"Blood pressure and fluid balance are regulated hormonally by renin-angiotensin system (RAS). Influence on this system could be achieved by different compounds that act as angiotensin-converting enzyme inhibitors (ACE inhibitors), angiotensin receptor blockers and renin inhibitors. The purpose of the present study is to predict the structures of the potent ACE inhibitors on the base of His-Leu peptide structural element of angiotensine I using computational methods. Different modifications were made in the structure of this dipeptide and the energy of binding with the enzyme were calculated. The docking results were analyzed and it was found that along with the important amino acid residue of the receptor molecule Arg167, the Tyr residues (35, 87, 88 and 92) as well as Cys180 areextremely important for the strong binding to the receptor and, accordingly, the manifestation of antagonistic action by the analogues. To block the receptor, the ligand molecule must have an intact terminal carboxyl group and an imidazole nucleus to participate in appropriate interactions. The inclusion of functional groups in the side chains of the amino acid residues of the dipeptide create an additional site for binding to the receptor. With the help of docking, the ligand molecule can be optimized, and this process is fast,  aving the synthesis of many compounds and their biological testing. And finally, the most potent analogues will be synthesized and biologically tested. ","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":" 37","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141674927","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}

{"title":"COMPUTATIONAL MODELING OF COMPOUNDS THAT INTERACT WITH OPIOID AND CANNABINOID RECEPTORS","authors":"Fatima Sapundzhi, T. Dzimbova","doi":"10.59957/jctm.v59.i4.2024.17","DOIUrl":"https://doi.org/10.59957/jctm.v59.i4.2024.17","url":null,"abstract":"The present study was designed to investigate the structure-activity relationship between cannabinoid and opioid ligands with models of cannabinoid and opioid receptors. There are differences in the mechanisms of pain control for these two types of receptors, but targeting the creation of compounds that bind to both opioid and cannabinoid receptors lead to more effective solving of this problem. This will lead to the development of new and improved strategies to prevent opiate addiction and its consequences.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":" 46","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141674940","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}

{"title":"BENZYDAMINE HYDROCHLORIDE IMMOBILIZATION IN MULTILAYER STRUCTURES BASED ON LYOPHILIZED COMPOSITE POLYLACTIC ACID / POLY(Ε-CAPROLACTONE) SUBSTRATES","authors":"A. Viraneva, M. Marudova, A. Grigorov, T. Yovcheva","doi":"10.59957/jctm.v59.i4.2024.10","DOIUrl":"https://doi.org/10.59957/jctm.v59.i4.2024.10","url":null,"abstract":"In the present paper the polyelectrolyte multilayers (PEMs) deposited on lyophilized composite polylactic acid / poly(ε-caprolactone) substrates were investigated. The substrates were charged under positive corona discharge for 1 min with 5 kV voltage applied to the corona electrode and 1 kV voltage of the same polarity applied to the grid. The dependences on the time of storage of the normalized surface potential of the charged substrates (positive) were investigated. Solutions of 1 % casein in phosphate buffer (pH 8) and 0.1 % chitosan in acetate buffer (pH 5) with added benzydamine hydrochloride were prepared. The creation of the multilayers was carried out by utilizing the technique Layer-by-Layer (LbL). The first built-up layer always possesses an electric charge opposite to that of the substrate. The loading efficiency and drug release kinetics of the chosen model drug were carried out spectrophotometrically.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":" 46","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141676991","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}

{"title":"EVALUATION OF ANTIOXIDANT PROPERTIES AND PHYTOCHEMICAL COMPOSITION IN VARIETAL HONEYS","authors":"Petranka Petrova, J. Mrmošanin, Stefan Petrović, M. Chochkova, Vesna Stankov Jovanović","doi":"10.59957/jctm.v59.i4.2024.4","DOIUrl":"https://doi.org/10.59957/jctm.v59.i4.2024.4","url":null,"abstract":"A total of fourteen honey samples, including monofloral, polyfloral, and honeydew honeys, collected from Bulgaria, Turkiye, and Morocco were analyzed with the aim to investigate the influence of floral origin on the biological properties of honey.The antioxidant activities of the samples were estimated using the DPPH, ABTS, FRAP, and CUPRAC methods, as well as analyzing their phytochemical composition by measuring the total phenolic content through the Folin-Ciocalteu method and individual polyphenols by HPLC.The results demonstrated that honeydew honey exhibited the highest total phenolic content and antioxidant activity among all the samples tested. It was followed by linden and forest honeys, which also demonstrated significant biological activity. In contrast, acacia and ziziphus honeys displayed the lowest levels of phenolic content and antioxidant properties among the samples.Our results indicated that while the botanical origin of honey had a significant influence on its biological properties, other factors such as geographical location also played a role in determining its quality. The observed variations among the honey samples from the same botanical origin could be attributed to factors such as specific landscape conditions, including whether the honey was sourced from an urban or rural area, the timing of harvest, beekeeping practices, and storage conditions.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":" 35","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141674982","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}

{"title":"SEARCH FOR DECAY OF THE 7Be NUCLEUS IN 8B NUCLEUS DISSOCIATION","authors":"R. Stanoeva, S. Kolev, Тatyana Koutzarova","doi":"10.59957/jctm.v59.i4.2024.28","DOIUrl":"https://doi.org/10.59957/jctm.v59.i4.2024.28","url":null,"abstract":"The fragmentation of light relativistic nuclei can be studied in detail by the technique of nuclear track emulsions. The registration of all charged particles and their identification enable one to explore the isotopic composition of fragments and the projectile fragmentation channels. In the present paper results of an analysis of decay of the 7Be nucleus in dissociation of 8B nuclei are presented and a comparative analysis of the experimental data with the Monte Carlo model calculations is made. The paper is illustrated with characteristic images, obtained by means of a microscope, equipped with a CCD camera.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":" 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141676928","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}

{"title":"LASER SYNTHESIS AND PROCESSING OF COMPOSITE NANOSTRUCTURES","authors":"M. Koleva, Anna Dikovska, N. Nedyalkov, Tsanislava Genova, G. Atanasova","doi":"10.59957/jctm.v59.i4.2024.11","DOIUrl":"https://doi.org/10.59957/jctm.v59.i4.2024.11","url":null,"abstract":"The present work reports the fabrication of porous composite ZnO/noble metal (Ag, Au) nanostructures using ps-pulsed laser deposition at atmospheric pressure. The PLD grown samples are ns-laser annealed, which led to a surface modification and formation of nanoparticles and NP’s aggregates. The effect of laser annealing procedure on the morphology, structure and optical properties of composite nanostructures is studied. The experimental results indicate that the laser annealing changes the plasmon resonance absorption mostly in the silver-doped samples. The laser modification plays a key role in tuning the PL performance for all samples by different mechanisms. Along with the increase in UV emission, there is a corresponding decrease in the broadband defect emission with the laser modification of composite nanostructures. The plasmon resonance absorption contributes to the enhancement of photoluminescence band-edge UV emission of the silver doped samples, while the PL performance of nanostructured ZnO/Au samples is attributed to the surface-plasmon-mediated sequential transfer of defect energy from ZnO to Au and electron transfer from excited Au to ZnO.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":" 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141675152","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}

{"title":"ASSESSMENT OF HEAVY METAL CONTAMINANTS IN GROUNDWATER AROUND MINING AREA BY USING METAL POLLUTION INDICES MULTIVARIATE ANALYSIS AND GIS TECHNIQUE","authors":"Vijayendra Pratap Dheeraj, C. S. Singh, A. K. Sonkar, Saurabh Kumar Barman","doi":"10.59957/jctm.v59.i4.2024.20","DOIUrl":"https://doi.org/10.59957/jctm.v59.i4.2024.20","url":null,"abstract":"An opencast and underground coal mining each have the potential to have a negative impact on the groundwater table in terms of both its quantity and quality. Leachates from overburden dumps and industrial waste are another issue worldwide; they infiltrate into the groundwater and have a negative impact on the quality of it. A concern is that groundwater will become contaminated with heavy metals. Therefore, in the current study, the groundwater sample have been collected systematically from different sources of water in pre monsoon season (May) of 2022 around Korba coalfield (KCF). The collected water samples were examined for 9 different heavy metals by using ICP-MS (Inductively Coupled Plasma Mass Spectrometer-Perkin Elmer, Optima 4300 DV) instrument. In general,the concentrations of few metals such as Aluminium, Cadmium, Copper, Iron, Lead, and Zinc were found to be well below the acceptable limits of World Health Organization (WHO) and Bureau of Indian Standards (BIS) standard, however Manganese, Barium, and Nickel concentrations were observed to be above to desirable limits of WHO and BIS standard at a few sites which is similar to the results obtained by previous studies. These laboratory data were applied for the calculation of heavy metal pollution indices such as Heavy Metal Pollution Index (HPI), Heavy Metal Evaluation Index (HEI), and Contamination Index (Cd). The multiple approach used to evaluate the metal indices identifies that 80 % of HPI, 85 % of HEI, and 95 % of Cd for groundwater samples mostly classified as “lowto medium” class. The spatial diagram of these different indices showed a higher value in the south east part of the region suggesting that the heavy metal leaching from mining activities has little impact on the groundwater in the south east of the examined area. Multivariate statistical studies, like principal component analysis (PCA) analysis reveals that Fe, Pb, and Zn originate from anthropogenic sources like coal mining, while Al and Cd originate from both lithogenic and anthropogenic sources.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":" 17","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141673883","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}

{"title":"EVALUATION OF SOME CHEMICAL CHARACTERISTICS OF SPIRULINA FROM DIFFERENT MANUFACTURERS","authors":"Krastena Nikolova, Nadezhda Petkova, G. Antova, Z. Petkova, G. Gentscheva, Anelia Gerasimova, Irina Karadjova","doi":"10.59957/jctm.v59.i4.2024.7","DOIUrl":"https://doi.org/10.59957/jctm.v59.i4.2024.7","url":null,"abstract":"Some chemical characteristics of Spirulina from different countries (the USA, China, Belgium, and Bulgaria) were investigated. The study includes a comparative analysis of the content of some elements, tocopherols, and fatty acids in spirulina. The total lipids of the examined sample varied from 1.9 % (China) to 6.1 % (Belgium). Gas chromatography was used to determine the fatty acid composition of glyceride oil isolated from spirulina of different origins. Inductively coupled plasma-optical emission spectrometry and liquid chromatography were used to determine the elemental composition and tocopherol content. The fat content of Spirulina from Bulgaria approaches that of China and the USA, while that of Belgium is almost three times higher. It was found that palmitic acid is the main saturated fatty acid in all samples, and for spirulina from Bulgaria, it reaches 81.2 %. The content of unsaturatedfatty acids is highest in that originating in the USA.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":" 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141674841","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}

{"title":"SYNTHESIS OF NOVEL BOLDINE AMIDES AND THEIR IN VITRO INHIBITORY EFFECTS ON A MUSHROOM TYROSINASE","authors":"M. Chochkova, B. Stoykova, Petranka Petrova, M. Štícha, Galya Ivanova","doi":"10.59957/jctm.v59.i4.2024.14","DOIUrl":"https://doi.org/10.59957/jctm.v59.i4.2024.14","url":null,"abstract":"Boldine ((S)-2,9-dihydroxy-1,10-dimethoxy-aporphine) has been defined as the major alkaloid in Chilean boldo tree. Besides its diverse pharmacological activities, e.g. neuroprotective, cytoprotective, anti-inflammatory activities, boldine also exhibits tyrosinase-inhibiting effect. Tyrosinase [EC 1.14.18.1] is well known as a bifunctional enzyme that is responsible for the melanin biosynthesis. Considering the diphenolic structural feature of the alkaloid, which is associated with its tyrosinase inhibitory properties, herein we first modified the boldine core and then linked it with the natural phenolic antioxidants such as: caffeic-, ferulic- and sinapic acids. Furthermore, the newly amides were tested in vitro on the mushroom tyrosinase. Our results indicated, that amongst the tested boldine derivatives, caffeoyl- and feruloylamides have shown the anti-tyrosinase activity closely correlated with a hydroquinone, used as a standard.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":" 22","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141675517","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}