Cogent Chemistry最新文献_第5页

Modeling the characteristics and quantification of adulterants in gasoline using FTIR spectroscopy and chemometric calibrations 利用FTIR光谱和化学计量校准模拟汽油中掺杂物的特性和定量

Cogent Chemistry Pub Date : 2018-01-01 DOI: 10.1080/23312009.2018.1482637

J. Dadson, S. Pandam, N. Asiedu

{"title":"Modeling the characteristics and quantification of adulterants in gasoline using FTIR spectroscopy and chemometric calibrations","authors":"J. Dadson, S. Pandam, N. Asiedu","doi":"10.1080/23312009.2018.1482637","DOIUrl":"https://doi.org/10.1080/23312009.2018.1482637","url":null,"abstract":"Abstract The criminal act of fuel (gasoline) adulteration still remains a global worry due to its environmental, health and economic effect. Current methods for the detection of fuel adulteration have not been effective in most developing countries due to the associated cost of implementation. Therefore, there is the need for a fast, reliable and cheaper approach for screening of adulterants in fuel. This study combined FTIR analyses with Chemometric (multivariate) techniques for qualitative and quantitative determination of four possible adulterants: kerosene, diesel, naphtha and premix in gasoline. Synthetic admixtures prepared by mixing the gasoline with varying proportions of the adulterants were obtained and used for the model calibration. Soft Independent Modeling Class Analogy (SIMCA) classification and Partial Least Square (PLS) regression methods were the Chemometric techniques employed. The SIMCA classification model developed predicted the type of adulterant present at an error rate of 6.25% for Kerosene and naphtha, and 12.5% for premix. However, no prediction error was recorded for classifying samples contaminated with diesel. The PLS regression model was able to predict the concentrations of adulterant with prediction errors lower than 5% for all adulterants considered. Applying the models to commercial gasoline samples collected from a Metropolis in Ghana revealed 7% gasoline adulteration with kerosene (4%), premix (2%) or diesel (1%). No adulteration with naphtha was detected. The FTIR-Chemometric approach proved a fast and cheaper method for detection of adulteration which can be adopted by quality assurance and monitoring laboratories for forensic screening of gasoline in Ghana","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1482637","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41416150","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}

引用次数: 11

Determination of the level of hexavalent, trivalent, and total chromium in the discharged effluent of Bahir Dar tannery using ICP-OES and UV–Visible spectrometry 使用ICP-OES和紫外-可见光谱法测定巴希尔达尔制革厂排放废水中的六价、三价和总铬含量

Cogent Chemistry Pub Date : 2018-01-01 DOI: 10.1080/23312009.2018.1534566

Fikirte Zewdu, Meareg Amare

{"title":"Determination of the level of hexavalent, trivalent, and total chromium in the discharged effluent of Bahir Dar tannery using ICP-OES and UV–Visible spectrometry","authors":"Fikirte Zewdu, Meareg Amare","doi":"10.1080/23312009.2018.1534566","DOIUrl":"https://doi.org/10.1080/23312009.2018.1534566","url":null,"abstract":"Abstract Tanneries that employ chrome tanning are indicted for discharging their effluents contaminated with health hazard chromium species necessitating monitoring their levels. The levels of chromium species (total chromium, hexavalent chromium, and trivalent chromium) in the discharged effluent of Bahir Dar tannery, Ethiopia, were determined using the inductively coupled plasma optical emission spectrometry, ultra-violet spectrometry and by difference, respectively. The level of total chromium in the discharged tannery effluent sample collected before and after treatment was 82.40 ± 0.20 ppm and 2.96 ± 0.06 ppm, respectively showing that the total chromium concentration in the tannery waste discharged directly to the Blue Nile river water system is above the national permitted limit (2 ppm). Moreover, the concentration of the carcinogenic chromium species (hexavalent chromium) detected in the tannery effluent sample collected before and after treatment was 0.18 ± 0.01 and 0.08 ± 0.002 ppm, respectively indicating that the discharged tannery effluent adds the carcinogenic chromium species to the Blue Nile River in a level above the recommended level by WHO guidelines. The result necessitates the assessment of the level of chromium species in the discharged effluent of all the tanneries in the country.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1534566","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47564112","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}

引用次数: 19

Synthesis of new heterocyclic 3-piperidinyl-1,3,4-oxadiazole derivatives as potential drug candidate for the treatment of Alzheimer’s disease 新杂环3-哌啶基-1,3,4-恶二唑衍生物的合成作为治疗阿尔茨海默病的潜在候选药物

Cogent Chemistry Pub Date : 2018-01-01 DOI: 10.1080/23312009.2018.1472197

A. Rehman, K. Nafeesa, M. Abbasi, S. Z. Siddiqui, S. Rasool, S. Shah, M. Ashraf

{"title":"Synthesis of new heterocyclic 3-piperidinyl-1,3,4-oxadiazole derivatives as potential drug candidate for the treatment of Alzheimer’s disease","authors":"A. Rehman, K. Nafeesa, M. Abbasi, S. Z. Siddiqui, S. Rasool, S. Shah, M. Ashraf","doi":"10.1080/23312009.2018.1472197","DOIUrl":"https://doi.org/10.1080/23312009.2018.1472197","url":null,"abstract":"Abstract A series of new N-substituted derivatives of 3-[(5-{1-[(4-chlorophenyl)sulfonyl]-3-piperidinyl}-1,3,4-oxadiazol-2-yl)sulfanyl]propanamide (7a–q) was synthesized to evaluate new drug candidates for Alzheimer’s disease. 4-Chlorobenzenesulfonyl chloride (a) and ethyl piperidin-3-carboxylate (b) were converted into 5-{1-[(4-chlorophenyl)sulfonyl]-3-piperidinyl}-1,3,4-oxadiazol-2-thiol (3) through a series of three steps. A series of electrophiles, N-alkyl/aralkyl/aryl-3-bromopropanamide (6a–q), was synthesized by gearing up 3-bromopropionyl chloride (5) with different alkyl/aralkyl/aryl amines (4a–q). Target compounds were synthesized by reacting compound 3 with different electrophiles, 6a–q, under basic conditions in an aprotic polar solvent. The synthesized compounds were subjected to spectral analysis, EI-MS, IR, 1H-NMR and 13C-NMR, for structural elucidation. The compounds were screened for enzyme inhibition activity against acetyl cholinesterase (AChE) enzyme. The validity of synthesized compounds as new drug candidates was also evaluated through haemolytic activity.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1472197","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49116531","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}

引用次数: 8

A fiber-optic refractive index sensor detects the isoelectric point of gelatin 光纤折射率传感器检测明胶的等电点

Cogent Chemistry Pub Date : 2018-01-01 DOI: 10.1080/23312009.2018.1466416

L. Zhang, Bao-kai Zhang, H. Lei, H. Meng, Xuguang Huang, Chunhua Tan

{"title":"A fiber-optic refractive index sensor detects the isoelectric point of gelatin","authors":"L. Zhang, Bao-kai Zhang, H. Lei, H. Meng, Xuguang Huang, Chunhua Tan","doi":"10.1080/23312009.2018.1466416","DOIUrl":"https://doi.org/10.1080/23312009.2018.1466416","url":null,"abstract":"Abstract In the present study, a set-up and a rapid method were developed to determine the isoelectric point (pI) of gelatin based on the combination of an automatic adding solution technique and fiber-optic refractive index sensing. The refractive index of the gelatin aqueous solution was measured as a function of pH and time using a fiber-optic sensor and pH meter. This is a typical acid-base titration process. The peak pH values of the refractive index-pH curve indicate the pI of the gelatins. With the aid of virtual instrument technology, the data acquisition, process and display were automatic, having the advantages of quick and labor saving. Furthermore, this improved analysis efficiency and reduced manual disturbance, which was typically an approximately 15 min period. The pI of these two kinds of gelatin, sample 1 and 2 were determined through this method and the pI s were consistent with the values obtained using a rotary viscometer. The test results revealed that this method is rapid, sensitive, accurate, and labor and reagent saving, and has the potential for the rapid determination of the pI of amino acids and proteins. GRAPHICAL ABSTRACT","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1466416","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44886762","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}

引用次数: 1

Trace metal concentrations in three pastry products prepared from root and tuber and cereal crops composite flours 由块根、块茎和谷类复合面粉制成的三种糕点产品中的痕量金属浓度

Cogent Chemistry Pub Date : 2018-01-01 DOI: 10.1080/23312009.2018.1429157

C. Tortoe, H. Ofori, P. T. Akonor, Hannah Oduro-Obeng

{"title":"Trace metal concentrations in three pastry products prepared from root and tuber and cereal crops composite flours","authors":"C. Tortoe, H. Ofori, P. T. Akonor, Hannah Oduro-Obeng","doi":"10.1080/23312009.2018.1429157","DOIUrl":"https://doi.org/10.1080/23312009.2018.1429157","url":null,"abstract":"Abstract The concentrations of Arsenic (As), Lead (Pb), Mercury (Hg), Copper (Cu), Iron (Fe), and Zinc (Zn) in doughnuts, cookies, and bread prepared from root and tuber and cereal crops composite flours were quantitatively measured by Atomic Absorption Spectrophotometry. Varying concentrations of trace metals were identified in three pastry products. Concentration of Hg was <0.01 mg/kg wet weight in all three pastry products. The As levels in all three pastry products ranged between <0.01 and 0.03 mg/kg. Concentrations of Pb was <0.01–0.05 mg/kg, far lesser than 10 mg/kg recommended limit by World Health Organization (WHO). The highest Fe level of 66.3 mg/kg occurred in cookies made from millet composite flour, whereas the lowest value of 10.4 mg/kg was in doughnuts made from water yam composite flour. Concentrations of Cu (1.03–1.83 mg/kg) and Zn (5.49–13.72 mg/kg) were lower than the tolerance limit of 40 mg/kg set by WHO. The presence of trace metals at varying concentrations in all three pastry products demonstrates the need for observing food safety controls in sourcing for raw materials and during processing of flours from root and tuber and cereal crops.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1429157","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48636047","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}

引用次数: 3

Compounds with 1,3,4-oxadiazole and azinane appendages to evaluate enzymes inhibition applications supported by docking and BSA binding 具有1,3,4-恶二唑和氮烷附件的化合物评价对接和BSA结合支持的酶抑制应用

Cogent Chemistry Pub Date : 2018-01-01 DOI: 10.1080/23312009.2018.1441597

A. Rehman, J. Iqbal, M. Abbasi, S. Z. Siddiqui, H. Khalid, S. Jhaumeer Laulloo, Naeem Akhtar Virk, S. Rasool, S. A. Shah

{"title":"Compounds with 1,3,4-oxadiazole and azinane appendages to evaluate enzymes inhibition applications supported by docking and BSA binding","authors":"A. Rehman, J. Iqbal, M. Abbasi, S. Z. Siddiqui, H. Khalid, S. Jhaumeer Laulloo, Naeem Akhtar Virk, S. Rasool, S. A. Shah","doi":"10.1080/23312009.2018.1441597","DOIUrl":"https://doi.org/10.1080/23312009.2018.1441597","url":null,"abstract":"Abstract The current research was designed for selective green synthesis of N-(substituted)-2-(5-(1-(4-nitrophenylsulfonyl)piperidin-4-yl)-1,3,4-oxadiazol-2-ylthio)acetamide hybrids and their pharmacological applications to overcome the enzymatic diseases. Environment friendly sodium hydride as an activator was employed to catalyze the reaction for the synthesis of target compounds. Structural characterization was performed using spectroscopic techniques (1H-NMR, 13C-NMR, IR, and EI-MS). All of the synthesized compounds were screened for acetylcholinesterase (AChE) and urease inhibition potential. Three compounds, 6a, 6k, and 6p, were found to be the best inhibitors of AChE enzyme and the whole array of compounds showed urease inhibition potential even better than the reference. Eserine was the reference standard for AChE inhibition and thiourea for urease inhibition. The computational and BSA binding studies were performed to explore the binding modes and interaction between synthesized compounds and respective enzymes. Molecular docking studies explained the presence of some hydrophobic interactions and have good correlation with calculated free energy of binding (DG binding). The finding of these new unique compounds having high potential to inhibit the activity of urease enzyme as compared to standard showing the prospective to replace the existing drugs and surprisingly effective addition of highly active drug discovery in the field of pharmacology against described enzyme.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1441597","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48720600","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}

引用次数: 8

Characterization of Silybum marianum triacylglycerol regioisomers using accurate mass quadrupole time of flight mass spectrometry 准确质量四极杆飞行时间质谱法表征水飞蓟三酰甘油区域异构体

Cogent Chemistry Pub Date : 2018-01-01 DOI: 10.1080/23312009.2018.1477246

Thao Nguyen, Duma Hlangothi, M. Saleh

引用次数: 4

Chemical composition and antimicrobial activity of leave extract of Ocimum lamiifolium (Damakese) as a treatment for urinary tract infection 拉米夫林叶提取物治疗尿路感染的化学成分及抗菌活性

Cogent Chemistry Pub Date : 2018-01-01 DOI: 10.1080/23312009.2018.1440894

Niguse Aweke Sahalie, Lijalem Hadush Abrha, L. D. Tolesa

{"title":"Chemical composition and antimicrobial activity of leave extract of Ocimum lamiifolium (Damakese) as a treatment for urinary tract infection","authors":"Niguse Aweke Sahalie, Lijalem Hadush Abrha, L. D. Tolesa","doi":"10.1080/23312009.2018.1440894","DOIUrl":"https://doi.org/10.1080/23312009.2018.1440894","url":null,"abstract":"Abstract Natural products obtained from aromatic plants are considered to be one of the potential sources for the screening of antimicrobial, antioxidant, and free radical scavenging agents. Ocimum Lamiifolium (Damakese) is one of the well-known celebrated and most widely used home remedies. The shade dried leaves of Ocimum Lamiifolium were subjected to hydrodistillation in a Clevenger-type apparatus to extract its essential oil. The yield of hydrodistilled colorless, pungent odor oil was found to be 0.22% (v/w). The chemical composition of the oil was analyzed by GC-MS method. Ten constituents were identified representing 93.56% of the total oil. The main constituents of the oil were found to be Linalool (28.52%) and 1-octen-3-yl-npropionate (20.82%) followed by 3,7,11-trimethyl-(E,E)-2,6,10-dodecatrienal (12.14%). The yield of crude extract of Ocimum Lamiifolium was 0.28% (w/w). Phytochemical screening revealed the presence of terpenoids, flavonoids, tannin, saponins and steroids. The in vitro antibacterial activity of Ocimum Lamiifolium leaf ethanol extract and essential oil was studied by using disc diffusion method. The oil exhibited significant zone of inhibitions against to E. coli bacterial strains.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1440894","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42931357","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}

引用次数: 12

Furanocoumarins from Kaffir lime and their inhibitory effects on inflammatory mediator production 石灰中呋喃香豆素及其对炎症介质产生的抑制作用

Cogent Chemistry Pub Date : 2018-01-01 DOI: 10.1080/23312009.2018.1529259

Saisakun Kidarn, C. Saenjum, Darunee Hongwiset, A. Phrutivorapongkul

{"title":"Furanocoumarins from Kaffir lime and their inhibitory effects on inflammatory mediator production","authors":"Saisakun Kidarn, C. Saenjum, Darunee Hongwiset, A. Phrutivorapongkul","doi":"10.1080/23312009.2018.1529259","DOIUrl":"https://doi.org/10.1080/23312009.2018.1529259","url":null,"abstract":"Abstract Two known furanocoumarins, namely, 6ˊ, 7ˊ-dihydroxybergamottin (1) and oxypeucedanin hydrate (2), were isolated from Kaffir lime (Citrus hystrix DC) fruit peel using an assay of nitric oxide scavenging effect-guided fractionation. The inhibitory activities of isolated coumarins on the production of nitric oxide (NO) and inducible nitric oxide synthase (iNOS) were studied in mouse macrophages RAW264.7 cells, whereas their inhibitory effect on cyclooxygenase-2 (COX-2) production was investigated using HT-29 and HCT116 cells. The results demonstrated that 1 inhibited lipopolysaccharide-interferon gamma-induced NO and iNOS production in RAW264.7 cells and COX-2 production in HT-29 and HCT116 cells with IC50 values of 16.16 ± 1.08, 18.63 ± 1.42, 18.19 ± 0.95 and 17.53 ± 0.88 µg/mL, respectively; 2 showed IC50 values of 18.23 ± 1.25, 22.54 ± 1.56, 22.27 ± 1.14 and 23.24 ± 1.05 µg/mL, respectively. Additionally, the positive control curcumin exhibited these activities with IC50 values of 12.52 ± 0.63, 15.55 ± 1.34, 14.29 ± 0.58 and 16.14 ± 0.65 µg/mL, respectively. The inhibitory effect of 1 on the production of iNOS and COX-2 was significantly stronger than that of 2. This study indicated that furanocoumarins from Kaffir lime fruit peels have potency for further development as an anti-inflammatory drug.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2018.1529259","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47243750","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}

引用次数: 10

Insilico modelling of quantitative structure–activity relationship of pGI50 anticancer compounds on K-562 cell line pGI50抗癌化合物在K-562细胞系上定量构效关系的计算机模拟

Cogent Chemistry Pub Date : 2018-01-01 DOI: 10.1080/23312009.2018.1432520

D. Arthur, A. Uzairu, P. Mamza, S. Abechi, Gideon Adamu Shallangwa

引用次数: 11