Pub Date : 2017-01-01DOI: 10.1080/23312009.2017.1388140
Kom Blaise, N. Y. Nicolas, B. Clémence, K. Richard
Abstract Leguminous plants have been used for centuries by rural communities as food, medicine and for cosmetic applications. The aim of this study was to evaluate the influence of spray-drying temperature on physicochemical and functional properties of protein isolates from three leguminous species. We found that pH is a major parameter of proteins’ solubility. The highest solubility was observed at pH 2 and between pH 8–12. The isoelectric pH was 4.5. The protein content of protein isolates was between 78.97% for Vigna Unguiculata and 88.43% for Glycine max. Highest water absorption capacity was observed when spray-drying temperature was at 130°C. The smallest gelling concentration of isolates was between 18 and 20% for G. max; 14–16% for V. Unguiculata; and 8–12% for C. ensiformis. The coalescence phenomenon followed by clarification was observed on emulsions after 24 h with the help of a turbiscan. The granulometric distribution of emulsions was monomodal.
{"title":"Influence of spray-drying temperature on physicochemical and functional properties of protein isolates of three leguminous plants (Canavalia ensiformis, Vigna unguiculata and Glycine max) from Cameroon","authors":"Kom Blaise, N. Y. Nicolas, B. Clémence, K. Richard","doi":"10.1080/23312009.2017.1388140","DOIUrl":"https://doi.org/10.1080/23312009.2017.1388140","url":null,"abstract":"Abstract Leguminous plants have been used for centuries by rural communities as food, medicine and for cosmetic applications. The aim of this study was to evaluate the influence of spray-drying temperature on physicochemical and functional properties of protein isolates from three leguminous species. We found that pH is a major parameter of proteins’ solubility. The highest solubility was observed at pH 2 and between pH 8–12. The isoelectric pH was 4.5. The protein content of protein isolates was between 78.97% for Vigna Unguiculata and 88.43% for Glycine max. Highest water absorption capacity was observed when spray-drying temperature was at 130°C. The smallest gelling concentration of isolates was between 18 and 20% for G. max; 14–16% for V. Unguiculata; and 8–12% for C. ensiformis. The coalescence phenomenon followed by clarification was observed on emulsions after 24 h with the help of a turbiscan. The granulometric distribution of emulsions was monomodal.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2017.1388140","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42469628","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}
Pub Date : 2017-01-01DOI: 10.1080/23312009.2017.1301242
R. Nakache, T. Touil, A. El hessni, A. Ouichou, Y. Bahbiti, I. Berkiks, Miloud Chakit, A. Mesfioui
Abstract The quinoxaline derivatives are an important class of heterocyclic compounds, obtained from chemical azote replacement of carbone atom. Fusion of quinoxaline production is relatively easy as they are obviously synthesized by the fusion of two aromatic rings, benzene and pyrazine. The new quinoxalinique derivative, 6-nitro-2 (1H)-quinoxalinone (NQX), has been synthesized in our laboratory. However, the related toxic effect on rat remains unknown. The present work aims to study the acute toxicity of NQX in normal Wistar rats. Seven groups of female rats received an intraperitoneal (i.p.) injection of 0 (control), 20, 40, 60, 120, 200 and 300 mg/kg of the NQX and followed for 14 days. Mortalities, behavioural changes, weight, changes in food and water uptake, urine output and weight of faeces were monitored. At the end of the experiment, the rats receiving the no-observed-adverse-effect level (NOAEL) are sacrificed, blood and organs were collected and haematological and biochemical parameters were analysed in sera sample. The results showed that the NQX Lethal Dose 50 (LD50) was 161.16 mg/kg. The administration of NQX at a dose of 40 mg/kg (NOAEL dose) did not affect animal viability and body weight. In addition, food intake, water intake and urine output remain unchanged. Furthermore, at the NOAEL dose, the levels of blood cells (erythrocytes and leukocytes), haemoglobin, biochemical parameters (glucose, cholesterol, triglycerides, urea, creatinine, bilirubin, total protein and transaminase) and organ’s weights (liver, kidney, spleen, pancreas, heart and brain) were not affected. NQX seems to be relatively saved at the dose of 40 mg/kg in normal Wistar rats and could possibly be tested after further analysis in a preliminary clinical test.
{"title":"In vivo acute toxicity assessment of a novel quinoxalinone (6-nitro-2 (1H)-quinoxalinone) in Wistar rats","authors":"R. Nakache, T. Touil, A. El hessni, A. Ouichou, Y. Bahbiti, I. Berkiks, Miloud Chakit, A. Mesfioui","doi":"10.1080/23312009.2017.1301242","DOIUrl":"https://doi.org/10.1080/23312009.2017.1301242","url":null,"abstract":"Abstract The quinoxaline derivatives are an important class of heterocyclic compounds, obtained from chemical azote replacement of carbone atom. Fusion of quinoxaline production is relatively easy as they are obviously synthesized by the fusion of two aromatic rings, benzene and pyrazine. The new quinoxalinique derivative, 6-nitro-2 (1H)-quinoxalinone (NQX), has been synthesized in our laboratory. However, the related toxic effect on rat remains unknown. The present work aims to study the acute toxicity of NQX in normal Wistar rats. Seven groups of female rats received an intraperitoneal (i.p.) injection of 0 (control), 20, 40, 60, 120, 200 and 300 mg/kg of the NQX and followed for 14 days. Mortalities, behavioural changes, weight, changes in food and water uptake, urine output and weight of faeces were monitored. At the end of the experiment, the rats receiving the no-observed-adverse-effect level (NOAEL) are sacrificed, blood and organs were collected and haematological and biochemical parameters were analysed in sera sample. The results showed that the NQX Lethal Dose 50 (LD50) was 161.16 mg/kg. The administration of NQX at a dose of 40 mg/kg (NOAEL dose) did not affect animal viability and body weight. In addition, food intake, water intake and urine output remain unchanged. Furthermore, at the NOAEL dose, the levels of blood cells (erythrocytes and leukocytes), haemoglobin, biochemical parameters (glucose, cholesterol, triglycerides, urea, creatinine, bilirubin, total protein and transaminase) and organ’s weights (liver, kidney, spleen, pancreas, heart and brain) were not affected. NQX seems to be relatively saved at the dose of 40 mg/kg in normal Wistar rats and could possibly be tested after further analysis in a preliminary clinical test.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2017.1301242","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42594711","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}
Pub Date : 2017-01-01DOI: 10.1080/23312009.2017.1370684
K. Hachem, C. Faugeron-Girard, M. Kaid-Harche, V. Gloaguen
Abstract Xylan polysaccharides previously obtained from argan (Argania spinosa) leaves by sequential alkaline extractions and purified by chromatography on Sepharose CL-4B were fragmented by acid hydrolysis in 2 M HCl. The resulting fragments were separated by gel filtration on Biogel P2. The oligosaccharide fractions obtained were then characterized by gas–liquid chromatography (GLC) and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The results show the presence of acidic oligosaccharide motifs, some of which composed of xylose and 4-O-methylglucuronic acid and other ones comprising rhamnose and galacturonic acid.
摘要采用顺序碱萃取法从argan (Argania spinosa)叶片中提取木聚糖多糖，并用Sepharose CL-4B层析纯化木聚糖多糖。所得片段在Biogel P2上通过凝胶过滤分离。然后用气液色谱(GLC)和基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)对所得的低聚糖组分进行了表征。结果表明，多糖中存在由木糖和4- o -甲基葡萄糖醛酸组成的酸性寡糖基序，以及由鼠李糖和半乳糖醛酸组成的酸性寡糖基序。
{"title":"Acid hydrolysis of xylan polysaccharides fractions isolated from argan (Argania spinosa) leaves","authors":"K. Hachem, C. Faugeron-Girard, M. Kaid-Harche, V. Gloaguen","doi":"10.1080/23312009.2017.1370684","DOIUrl":"https://doi.org/10.1080/23312009.2017.1370684","url":null,"abstract":"Abstract Xylan polysaccharides previously obtained from argan (Argania spinosa) leaves by sequential alkaline extractions and purified by chromatography on Sepharose CL-4B were fragmented by acid hydrolysis in 2 M HCl. The resulting fragments were separated by gel filtration on Biogel P2. The oligosaccharide fractions obtained were then characterized by gas–liquid chromatography (GLC) and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The results show the presence of acidic oligosaccharide motifs, some of which composed of xylose and 4-O-methylglucuronic acid and other ones comprising rhamnose and galacturonic acid.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2017.1370684","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46873635","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}
Pub Date : 2017-01-01DOI: 10.1080/23312009.2017.1343636
Godfred Darko, Lawrence Sheringham Borquaye, Akwasi Acheampong, Kwasi Oppong
Abstract Consumption of traces of veterinary drug residues through dairy products could have adverse effects on human health. There is, therefore, the need for routine monitoring of drug residues in dairy products on the market. In this study, fresh milk, cheese, and yogurt being sold at different points in the Kumasi metropolis were analyzed for residues of chloramphenicol, sulfathiazole, sulfamethoxazole, and oxytetracycline — four commonly used veterinary drugs in the country. The concentrations found were generally very low and close to the method detection limit of 0.1 μg/kg. Concentration of chloramphenicol in yogurt (0.8 μg/L) was the highest among all the residues studied. However, with the residue levels being hundred folds lower than the maximum residue limit, they are highly unlikely to pose any health risks to the consumers. Therefore, as far as chloramphenicol, sulfathiazole, sulfamethoxazole, and oxytetracycline in fresh milk, cheese, and yogurt are concerned, this study did not indicate any risk of consumption.
{"title":"Veterinary antibiotics in dairy products from Kumasi, Ghana","authors":"Godfred Darko, Lawrence Sheringham Borquaye, Akwasi Acheampong, Kwasi Oppong","doi":"10.1080/23312009.2017.1343636","DOIUrl":"https://doi.org/10.1080/23312009.2017.1343636","url":null,"abstract":"Abstract Consumption of traces of veterinary drug residues through dairy products could have adverse effects on human health. There is, therefore, the need for routine monitoring of drug residues in dairy products on the market. In this study, fresh milk, cheese, and yogurt being sold at different points in the Kumasi metropolis were analyzed for residues of chloramphenicol, sulfathiazole, sulfamethoxazole, and oxytetracycline — four commonly used veterinary drugs in the country. The concentrations found were generally very low and close to the method detection limit of 0.1 μg/kg. Concentration of chloramphenicol in yogurt (0.8 μg/L) was the highest among all the residues studied. However, with the residue levels being hundred folds lower than the maximum residue limit, they are highly unlikely to pose any health risks to the consumers. Therefore, as far as chloramphenicol, sulfathiazole, sulfamethoxazole, and oxytetracycline in fresh milk, cheese, and yogurt are concerned, this study did not indicate any risk of consumption.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2017.1343636","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46953066","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}
Pub Date : 2017-01-01DOI: 10.1080/23312009.2017.1314064
L. Kambizi, M. T. Bakare-Odunola, A. Oladiji, A. Kola-Mustapha, T. O. Amusa, O. Atolani, N. Njinga, A. L. Quadri, Y. Mehellou
Abstract The aqueous extracts of the edible parts of four common medicinal plants (Hibiscus sabdariffa, Telfairia occidentalis, Moringa oleifera and Ocimum gratissimum) readily consumed as food or supplements in many African settings are examined for some of their acclaimed pharmacological activities and possible potential associated risks. The classes of phytochemicals present are examined qualitatively and quantitatively, while the antioxidant activities were determined using three assays which include 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonate (ABTS) and hydrogen peroxide (H2O2) assays. The anti-inflammatory activities were also examined using proteinase inhibitory assays and red blood cell membrane stabilisation assays. Both the antioxidant and anti-inflammatory activities of the plants indicated that the plants have potentials for applications in foods and nutraceuticals that can be used for the management of various ailments and diseases. However, the consumption of H. sabdariffa leaf should be highly regulated as the extract exhibited reduced cell membrane stabilisation activities at increased concentrations.
{"title":"Proteinease inhibition, membrane stabilization, antioxidant and phytochemical evaluations of leaves, seeds and calyces of four selected edible medicinal plants","authors":"L. Kambizi, M. T. Bakare-Odunola, A. Oladiji, A. Kola-Mustapha, T. O. Amusa, O. Atolani, N. Njinga, A. L. Quadri, Y. Mehellou","doi":"10.1080/23312009.2017.1314064","DOIUrl":"https://doi.org/10.1080/23312009.2017.1314064","url":null,"abstract":"Abstract The aqueous extracts of the edible parts of four common medicinal plants (Hibiscus sabdariffa, Telfairia occidentalis, Moringa oleifera and Ocimum gratissimum) readily consumed as food or supplements in many African settings are examined for some of their acclaimed pharmacological activities and possible potential associated risks. The classes of phytochemicals present are examined qualitatively and quantitatively, while the antioxidant activities were determined using three assays which include 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonate (ABTS) and hydrogen peroxide (H2O2) assays. The anti-inflammatory activities were also examined using proteinase inhibitory assays and red blood cell membrane stabilisation assays. Both the antioxidant and anti-inflammatory activities of the plants indicated that the plants have potentials for applications in foods and nutraceuticals that can be used for the management of various ailments and diseases. However, the consumption of H. sabdariffa leaf should be highly regulated as the extract exhibited reduced cell membrane stabilisation activities at increased concentrations.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2017.1314064","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43484028","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}
Pub Date : 2017-01-01DOI: 10.1080/23312009.2017.1363341
Mohamed Mohamady Ghobashy
Abstract Gamma radiation has been used for the fabrication of polyethylene (PE) wax from low density polyethylene pellets composited with 30wt% magnetic oxide Fe3O4 nanoparticles. The surface of (PE/Fe3O4) pellets was grafted by acrylic acid AAc using gamma irradiation techniques. A polarity of COOH groups support (PE/Fe3O4) uses, where functionalization give it facilities to be ready in hydrophilic and/or hydrophobic environments and increasing the capability in adsorbing wide variety of dyes molecules. Wax increases the stability and this will help to improve the recyclability of (PE-g-PAAc)/Fe3O4; recyclability is also helped by Fe3O4, compared to traditional dye adsorbents. The grafted polyethylene wax can serve as a good adsorbent support for a large variety of dyes. The chemical structure of the modified PE surface was achieved by a grafting process using attenuated total reflectance–Fourier transform infrared spectroscopy (ATR-FTIR). Samples of (PE-g-PAAc)/Fe3O4 have been characterized for water uptake and surface morphology using a scanning electron microscope (SEM); the crystal structure has been determined using X-ray diffraction; and dye removal efficiency was assessed using toluidine blue (TB) as a model.
{"title":"Functionalized of wax-magnetic nanocomposite (Fe3O4/PE) pellets by radiation grafting of PAAc for safe dye removal","authors":"Mohamed Mohamady Ghobashy","doi":"10.1080/23312009.2017.1363341","DOIUrl":"https://doi.org/10.1080/23312009.2017.1363341","url":null,"abstract":"Abstract Gamma radiation has been used for the fabrication of polyethylene (PE) wax from low density polyethylene pellets composited with 30wt% magnetic oxide Fe3O4 nanoparticles. The surface of (PE/Fe3O4) pellets was grafted by acrylic acid AAc using gamma irradiation techniques. A polarity of COOH groups support (PE/Fe3O4) uses, where functionalization give it facilities to be ready in hydrophilic and/or hydrophobic environments and increasing the capability in adsorbing wide variety of dyes molecules. Wax increases the stability and this will help to improve the recyclability of (PE-g-PAAc)/Fe3O4; recyclability is also helped by Fe3O4, compared to traditional dye adsorbents. The grafted polyethylene wax can serve as a good adsorbent support for a large variety of dyes. The chemical structure of the modified PE surface was achieved by a grafting process using attenuated total reflectance–Fourier transform infrared spectroscopy (ATR-FTIR). Samples of (PE-g-PAAc)/Fe3O4 have been characterized for water uptake and surface morphology using a scanning electron microscope (SEM); the crystal structure has been determined using X-ray diffraction; and dye removal efficiency was assessed using toluidine blue (TB) as a model.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2017.1363341","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60090689","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}
Pub Date : 2017-01-01DOI: 10.1080/23312009.2017.1385173
Jana Váňová, L. Liimatta, P. Česla, S. Wiedmer
Abstract Liposome electrokinetic chromatography and micellar electrokinetic chromatography were used for studying the lipophilic properties of natural antioxidants, specifically phenolic acids and flavonoids. The employed negatively charged liposomes were composed of mixtures of 1-palmitoyl-2-oleyl-sn-glycerophosphatidylcholine and 1-palmitoyl-2-oleoyl-sn-phosphatidylserine or 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylglycerol. In micellar electrokinetic chromatography, sodium dodecyl sulphate micelles were used as the pseudostationary phase. The retention factors of the studied compounds were determined at pH 7.4. The corresponding distribution constants were calculated from the experimentally determined retention factors and the phase ratios of the liposome dispersions and the micellar system. The distribution constants between the aqueous phase and the liposomes or micelles were compared with octanol/water partition or distribution constants of the studied compounds, which were predicted using the ACD/Labs Percepta Platform—PhysChem Module. Our results indicate that the correlations between the distribution constants of the two tested liposome systems were much stronger than those between the liposome/micellar systems. The correlations between the n-octanol phase and the liposome phases were similar to that between n-octanol and the micellar phase. Our data shows that electrokinetic chromatography is an efficient method for determining partition coefficients of compounds, but the type of pseudostationary phase has a clear impact on the values.
{"title":"Determination of distribution constants of antioxidants by electrokinetic chromatography","authors":"Jana Váňová, L. Liimatta, P. Česla, S. Wiedmer","doi":"10.1080/23312009.2017.1385173","DOIUrl":"https://doi.org/10.1080/23312009.2017.1385173","url":null,"abstract":"Abstract Liposome electrokinetic chromatography and micellar electrokinetic chromatography were used for studying the lipophilic properties of natural antioxidants, specifically phenolic acids and flavonoids. The employed negatively charged liposomes were composed of mixtures of 1-palmitoyl-2-oleyl-sn-glycerophosphatidylcholine and 1-palmitoyl-2-oleoyl-sn-phosphatidylserine or 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylglycerol. In micellar electrokinetic chromatography, sodium dodecyl sulphate micelles were used as the pseudostationary phase. The retention factors of the studied compounds were determined at pH 7.4. The corresponding distribution constants were calculated from the experimentally determined retention factors and the phase ratios of the liposome dispersions and the micellar system. The distribution constants between the aqueous phase and the liposomes or micelles were compared with octanol/water partition or distribution constants of the studied compounds, which were predicted using the ACD/Labs Percepta Platform—PhysChem Module. Our results indicate that the correlations between the distribution constants of the two tested liposome systems were much stronger than those between the liposome/micellar systems. The correlations between the n-octanol phase and the liposome phases were similar to that between n-octanol and the micellar phase. Our data shows that electrokinetic chromatography is an efficient method for determining partition coefficients of compounds, but the type of pseudostationary phase has a clear impact on the values.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2017.1385173","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42736357","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}
Abstract We describe the syntheses of 3,4-dihydropyrimidinones or analogous thioketones by a one-pot cyclocondensation of acetoacetates, aldehydes and urea or thiourea using gallium (III) chloride as catalyst under solvent-free conditions. The improved Biginelli reaction not only features a simple procedure, high yields and easy purification of production, but also the recycled catalyst could be directly reused for many times while the yields of reaction would not decrease.
{"title":"Gallium (III) chloride-catalyzed synthesis of 3,4-dihydropyrimidinones for Biginelli reaction under solvent-free conditions","authors":"Haixin Yuan, Kehua Zhang, Jingjing Xia, Xianhai Hu, Shizhen Yuan","doi":"10.1080/23312009.2017.1318692","DOIUrl":"https://doi.org/10.1080/23312009.2017.1318692","url":null,"abstract":"Abstract We describe the syntheses of 3,4-dihydropyrimidinones or analogous thioketones by a one-pot cyclocondensation of acetoacetates, aldehydes and urea or thiourea using gallium (III) chloride as catalyst under solvent-free conditions. The improved Biginelli reaction not only features a simple procedure, high yields and easy purification of production, but also the recycled catalyst could be directly reused for many times while the yields of reaction would not decrease.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2017.1318692","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43250368","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}
Pub Date : 2017-01-01DOI: 10.1080/23312009.2017.1351653
A. Dada, F. A. Adekola, E. Odebunmi
Abstract The kinetics, mechanism, isotherm, and thermodynamics of adsorption of Pb2+ onto wood-activated carbon-supported zerovalent iron (WAC-nZVI) nanocomposite was successfully studied. WAC-nZVI was characterized by a combination of spectroscopic and analytical techniques (BET, PZC, FTIR, SEM, and EDX). BET surface area was 101.50 m2/g and BJH Adsorption average pore diameter 116.73 Å. The adsorption of Pb2+ studied in batch process depends on various operational parameters ranging from effect of pH to ionic strength. Kinetics data were best described by pseudo-second-order model based on high initial adsorption rate, h2 (166.67 mgg−1 min−1) and correlation coefficient (R2 > 0.99). The mechanism was controlled by both external and intraparticle diffusion models confirmed by Bangham and Boyd models. Equilibrium data were fitted to seven isotherm models. The Langmuir monolayer adsorption capacity (77.52 m2/g) surpassed those previously investigated for adsorption of Pb2+ onto nanoadsorbents. Validity of kinetics and isotherm models was studied using three statistical models. Post-adsorption characterization by SEM, EDX, and FTIR confirmed the presence of Pb2+ on the loaded-WAC-nZVI. Thermodynamic parameters (∆Ho, ∆So, ∆Go) confirmed the feasibility, spontaneity, and randomness of the adsorption process. This study revealed a great potential of novel WAC-nZVI in effective removal of Pb2+ from waste water.
{"title":"Kinetics, mechanism, isotherm and thermodynamic studies of liquid phase adsorption of Pb2+ onto wood activated carbon supported zerovalent iron (WAC-ZVI) nanocomposite","authors":"A. Dada, F. A. Adekola, E. Odebunmi","doi":"10.1080/23312009.2017.1351653","DOIUrl":"https://doi.org/10.1080/23312009.2017.1351653","url":null,"abstract":"Abstract The kinetics, mechanism, isotherm, and thermodynamics of adsorption of Pb2+ onto wood-activated carbon-supported zerovalent iron (WAC-nZVI) nanocomposite was successfully studied. WAC-nZVI was characterized by a combination of spectroscopic and analytical techniques (BET, PZC, FTIR, SEM, and EDX). BET surface area was 101.50 m2/g and BJH Adsorption average pore diameter 116.73 Å. The adsorption of Pb2+ studied in batch process depends on various operational parameters ranging from effect of pH to ionic strength. Kinetics data were best described by pseudo-second-order model based on high initial adsorption rate, h2 (166.67 mgg−1 min−1) and correlation coefficient (R2 > 0.99). The mechanism was controlled by both external and intraparticle diffusion models confirmed by Bangham and Boyd models. Equilibrium data were fitted to seven isotherm models. The Langmuir monolayer adsorption capacity (77.52 m2/g) surpassed those previously investigated for adsorption of Pb2+ onto nanoadsorbents. Validity of kinetics and isotherm models was studied using three statistical models. Post-adsorption characterization by SEM, EDX, and FTIR confirmed the presence of Pb2+ on the loaded-WAC-nZVI. Thermodynamic parameters (∆Ho, ∆So, ∆Go) confirmed the feasibility, spontaneity, and randomness of the adsorption process. This study revealed a great potential of novel WAC-nZVI in effective removal of Pb2+ from waste water.","PeriodicalId":10640,"journal":{"name":"Cogent Chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312009.2017.1351653","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41379593","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}
Pub Date : 2017-01-01DOI: 10.1080/23312009.2017.1318693
Nagi Reddy Modugu, Praveen Kumar Pittala
Abstract We report a mild, inexpensive, fast, highly efficient, and eco-friendly protocol for the synthesis of new isoxazolyl dihydro-1H-indol-4(5H)-ones by a catalyst-free, one-pot three-component reaction of 4-amino-3-methyl-5-styrylisoxazoles, dimedone, and 2-chloroacetophenones under 1-methyl imidazolium tetraflouroborate ([HMIm]BF4) as task-specific ionic liquid at room temperature. The important aspects of the present methodology are: use of green solvent, short reaction time, catalyst free, compatibility with wide range of substrates, ease of recovery, reusability of reaction medium, and good yields.
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