Abstract Three manganese complexes of the antibiotic doxycyline viz.: manganese doxycyline, [MnDox2]Cl2‧2H2O (1), and manganese doxycyline with bipyridine, [MnDox2(bpy)]Cl2‧8H2O (2), and phenanthroline, [MnDox2(phen)]Cl2‧8H2O (3), as the ancillary ligand were synthesized and characterized by FT-IR, elemental analysis and electrospray mass spectroscopy. The three complexes show good solubility in DMF and DMSO. Data obtained from spectroscopic techniques used show that doxycycline coordinates to the central manganese atom through the oxygen of the amide group and the carbonyl oxygen atom of ring A while bipyridine/phenanthroline coordinates through the two diimine nitrogen atoms. The stoichiometry of manganese-doxycycline is 1:2 and octahedral geometry is the preferred coordination in all the complexes.
{"title":"Synthesis, characterization and antibacterial susceptibility testing of manganese complexes of doxycyline with bipyridine and phenanthroline","authors":"J. Obaleye, O. Abosede","doi":"10.2478/auoc-2019-0013","DOIUrl":"https://doi.org/10.2478/auoc-2019-0013","url":null,"abstract":"Abstract Three manganese complexes of the antibiotic doxycyline viz.: manganese doxycyline, [MnDox2]Cl2‧2H2O (1), and manganese doxycyline with bipyridine, [MnDox2(bpy)]Cl2‧8H2O (2), and phenanthroline, [MnDox2(phen)]Cl2‧8H2O (3), as the ancillary ligand were synthesized and characterized by FT-IR, elemental analysis and electrospray mass spectroscopy. The three complexes show good solubility in DMF and DMSO. Data obtained from spectroscopic techniques used show that doxycycline coordinates to the central manganese atom through the oxygen of the amide group and the carbonyl oxygen atom of ring A while bipyridine/phenanthroline coordinates through the two diimine nitrogen atoms. The stoichiometry of manganese-doxycycline is 1:2 and octahedral geometry is the preferred coordination in all the complexes.","PeriodicalId":19641,"journal":{"name":"Ovidius University Annals of Chemistry","volume":"220 1","pages":"70 - 74"},"PeriodicalIF":0.9,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89127283","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 Lead ions mobility from spent metallic Pb bullets is under increasing scrutiny as a potential significant source of soil contamination. This study investigates effect of soil-properties types on Pb(II) mobility from spent corroded and non-corroded bullets and associated environmental risk using water, toxicity characteristic leaching procedure and synthetic precipitation leaching procedure as leaching techniques. From results, loamy soil properties (pH and organic matter-specific) apparently favored high mobility rate of Pb(II) (0.004 - 1.166 % Pb contamination) from spent bullets compared to sandy and clay soil types. Consequently, Pb(II) mobility from corroded bullet (0.035 - 1.166 %) was significant (p < 0.05) compared to non-corroded bullet (0.004 - 0.873 %) due largely to surface area differences. Percentage Pb contamination increased proportionally with bullet retention time in the different soils types. The experiment reported average decomposition rate of 6.9 g Pb/kg within a 28 weeks retention time. Leaching potential of Pb from spent bullet arising from water, toxicity characteristic leaching procedure and synthetic precipitation leaching procedure was quite significant (p < 0.05) in order of over 100 mg/L. Both toxicity characteristic leaching procedure-Pb and synthetic precipitation leaching procedure-Pb exceeded the 5 mg/L and 15 µg/L critical levels suggested by United State Environmental Protection Agency for Pb (II) mobility and hazardous classification. A significant positive correlation existed between corroded and non-corroded Pb (II) levels within each leaching solutions. Continued dissolution of metallic Pb (II) from spent Pb-bullets may be a mechanism for natural attenuation of Pb in soils. An important result of this study is the clear influence of soil properties on Pb mobility.
{"title":"Assessing lead mobility rate from spent corroded and non-corroded bullets fragments on different soil types of tropical ecosystems","authors":"E. U. Etim","doi":"10.2478/auoc-2019-0015","DOIUrl":"https://doi.org/10.2478/auoc-2019-0015","url":null,"abstract":"Abstract Lead ions mobility from spent metallic Pb bullets is under increasing scrutiny as a potential significant source of soil contamination. This study investigates effect of soil-properties types on Pb(II) mobility from spent corroded and non-corroded bullets and associated environmental risk using water, toxicity characteristic leaching procedure and synthetic precipitation leaching procedure as leaching techniques. From results, loamy soil properties (pH and organic matter-specific) apparently favored high mobility rate of Pb(II) (0.004 - 1.166 % Pb contamination) from spent bullets compared to sandy and clay soil types. Consequently, Pb(II) mobility from corroded bullet (0.035 - 1.166 %) was significant (p < 0.05) compared to non-corroded bullet (0.004 - 0.873 %) due largely to surface area differences. Percentage Pb contamination increased proportionally with bullet retention time in the different soils types. The experiment reported average decomposition rate of 6.9 g Pb/kg within a 28 weeks retention time. Leaching potential of Pb from spent bullet arising from water, toxicity characteristic leaching procedure and synthetic precipitation leaching procedure was quite significant (p < 0.05) in order of over 100 mg/L. Both toxicity characteristic leaching procedure-Pb and synthetic precipitation leaching procedure-Pb exceeded the 5 mg/L and 15 µg/L critical levels suggested by United State Environmental Protection Agency for Pb (II) mobility and hazardous classification. A significant positive correlation existed between corroded and non-corroded Pb (II) levels within each leaching solutions. Continued dissolution of metallic Pb (II) from spent Pb-bullets may be a mechanism for natural attenuation of Pb in soils. An important result of this study is the clear influence of soil properties on Pb mobility.","PeriodicalId":19641,"journal":{"name":"Ovidius University Annals of Chemistry","volume":"36 1","pages":"81 - 87"},"PeriodicalIF":0.9,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75926338","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}
Sridevi Chigurupati, S. Vijayabalan, A. Karunanidhi, Kesavanarayanan Krishnan Selvarajan, S. Nanda, R. Satpathy
Abstract Endophytes, notably obtaining attention, have been abided by potential origins of bioactive metabolites. In the acquaint study, endophyte was isolated from the leaves of Nephelium lappaceum L. The chosen endosymbiont was identified by 16s rRNA partial genome sequencing and investigated for their antioxidant and antidiabetic activities. A preliminary phytochemical test was comported for the affirmation of phytoconstituents in endophytic crude extract (NLM). Antioxidant activities were conducted by using 2-diphenyl-1-picrylhydrazyl (DPPH) method and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) method to screen the radical scavenging potential. The evaluation of antidiabetic activities was done by using α-amylase and α-glucosidase inhibition assay. Qualitative phytochemical test on NLM affirmed the presence of phenols, carbohydrates, alkaloids, flavonoids, steroids, mucilage and glycosides. In silico parameters were also specified for antidiabetic activities. The antioxidant assay of NLM expressed proficient antioxidant activity of IC50±SEM 1.35±0.03 µg/mL and IC50±SEM 1.47±0.03 µg/mL, for ABTS and DPPH respectively. Antidiabetic assay results evidenced dose dependent percentage inhibition of the enzyme. The results testified estimable inhibition of α-amylase (IC50±SEM 2.549±0.08 µg/mL) and α-glucosidase inhibition (IC50±SEM 2.29±0.03µg/mL) compared to the standard drug (Acarbose). In silico study divulged that the ellagic acid component present in the plant was responsible for antidiabetic activity. Thus, the study shows that NLM has a wellspring of natural source of antioxidants and antidiabetic agents and furtherance of studies on its mechanism is recommended to know detailed facts.
{"title":"Antidiabetic, antioxidant and in silico studies of bacterial endosymbiont inhabiting Nephelium lappaceum L.","authors":"Sridevi Chigurupati, S. Vijayabalan, A. Karunanidhi, Kesavanarayanan Krishnan Selvarajan, S. Nanda, R. Satpathy","doi":"10.2478/auoc-2019-0017","DOIUrl":"https://doi.org/10.2478/auoc-2019-0017","url":null,"abstract":"Abstract Endophytes, notably obtaining attention, have been abided by potential origins of bioactive metabolites. In the acquaint study, endophyte was isolated from the leaves of Nephelium lappaceum L. The chosen endosymbiont was identified by 16s rRNA partial genome sequencing and investigated for their antioxidant and antidiabetic activities. A preliminary phytochemical test was comported for the affirmation of phytoconstituents in endophytic crude extract (NLM). Antioxidant activities were conducted by using 2-diphenyl-1-picrylhydrazyl (DPPH) method and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) method to screen the radical scavenging potential. The evaluation of antidiabetic activities was done by using α-amylase and α-glucosidase inhibition assay. Qualitative phytochemical test on NLM affirmed the presence of phenols, carbohydrates, alkaloids, flavonoids, steroids, mucilage and glycosides. In silico parameters were also specified for antidiabetic activities. The antioxidant assay of NLM expressed proficient antioxidant activity of IC50±SEM 1.35±0.03 µg/mL and IC50±SEM 1.47±0.03 µg/mL, for ABTS and DPPH respectively. Antidiabetic assay results evidenced dose dependent percentage inhibition of the enzyme. The results testified estimable inhibition of α-amylase (IC50±SEM 2.549±0.08 µg/mL) and α-glucosidase inhibition (IC50±SEM 2.29±0.03µg/mL) compared to the standard drug (Acarbose). In silico study divulged that the ellagic acid component present in the plant was responsible for antidiabetic activity. Thus, the study shows that NLM has a wellspring of natural source of antioxidants and antidiabetic agents and furtherance of studies on its mechanism is recommended to know detailed facts.","PeriodicalId":19641,"journal":{"name":"Ovidius University Annals of Chemistry","volume":"3 1","pages":"95 - 100"},"PeriodicalIF":0.9,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84111451","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 The adsorption and inhibitive behavior of gums obtained from Mangifera indica tree was investigated at 303-333 K using weight loss and linear polarization measurements. The results obtained from both measurements showed that Mangifera indica gums inhibited the corrosion of mild steel in 1.0 M HCl. Linear polarization measurements revealed Mangifera indica gums to inhibit both the anodic and cathodic reactions on the surface of the mild steel thereby functioning as a mixed-type inhibitor. Adsorption behavior of the gums were approximated by the isotherm models of Langmuir, Freundlich and Temkin. The adsorption mechanism derived from the trend in inhibition efficiency as a function of temperature as well as kinetic and activation parameters signified Mangifera indica gums adsorbed on the surface of the mild steel through the mechanism of physisorption and that the adsorption process was exothermic and spontaneous.
摘要采用失重法和线极化法研究了芒果树胶在303 ~ 333 K温度下的吸附和抑制行为。结果表明，芒果胶对低碳钢在1.0 M HCl溶液中的腐蚀有抑制作用。线性极化测量结果表明，芒果树胶对低碳钢表面的阳极和阴极反应均有抑制作用，因此具有混合型缓蚀剂的作用。用Langmuir、Freundlich和Temkin等温模型模拟了胶的吸附行为。从抑制效率随温度、动力学参数和活化参数的变化趋势得出的吸附机理表明，芒果胶在低碳钢表面的吸附是通过物理吸附机制进行的，吸附过程是放热自发的。
{"title":"Adsorptive, inhibitive and thermodynamics studies on the corrosion of mild steel in the presence of Mangifera indica gums","authors":"H. F. Chahul, E. Maji, T. B. Danat","doi":"10.2478/auoc-2019-0014","DOIUrl":"https://doi.org/10.2478/auoc-2019-0014","url":null,"abstract":"Abstract The adsorption and inhibitive behavior of gums obtained from Mangifera indica tree was investigated at 303-333 K using weight loss and linear polarization measurements. The results obtained from both measurements showed that Mangifera indica gums inhibited the corrosion of mild steel in 1.0 M HCl. Linear polarization measurements revealed Mangifera indica gums to inhibit both the anodic and cathodic reactions on the surface of the mild steel thereby functioning as a mixed-type inhibitor. Adsorption behavior of the gums were approximated by the isotherm models of Langmuir, Freundlich and Temkin. The adsorption mechanism derived from the trend in inhibition efficiency as a function of temperature as well as kinetic and activation parameters signified Mangifera indica gums adsorbed on the surface of the mild steel through the mechanism of physisorption and that the adsorption process was exothermic and spontaneous.","PeriodicalId":19641,"journal":{"name":"Ovidius University Annals of Chemistry","volume":"1 1","pages":"75 - 80"},"PeriodicalIF":0.9,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89795596","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}
S. Adoga, Deborah Ehikowoicho Ekle, B. Kyenge, T. Aondo, C. Ikese
Abstract Parquetina nigrescens leaves have been used in traditional medicine as an important and highly efficacious herbal remedy and have been recommended as a potential source of antimicrobial agent. Three extracts of the plant obtained using n-hexane, methanol and water were used as solvents. Phytochemical analysis of the plant extracts showed important bioactive compounds such as flavonoids, saponins, tannins, terpenes, steroids, phenols and glycosides, but alkaloids were absent in all the three extracts. Agar disk diffusion method was used to study the antimicrobial activity of the extracts at different concentrations which showed activity against three gram negative bacteria Escherichia coli, Klebsiella pneumoniae and Proteus spp., one gram positive bacteria Staphylococcus aureus, and two fungus Aspergillus flavus and Candida albicans with zone of inhibition ranging from 5-15 mm for n-hexane extract, 6-16 mm for methanol extract and 1-11 mm for aqueous extract compared to zone of inhibition for the standard antibacterial drug, 0.5 mg/mL Streptomycin that ranges from 13 – 37 mm and the zone of inhibition for the standard antifungal drug 5 mg/mL fluconazole that ranges from 24 – 25 mm. Klebsiella pneumoniae was the most inhibited while E. coli was the least inhibited by the extract, and Candida albicans was found to be resistant to the extracts in all the concentrations. TLC finger-printing of the extracts using the solvent system – butanol : acetic acid : ethanol : distilled water in the ratio 50:10:10:30 showed spots with peaks different retention times ranging from 0.24 - 0.74 cm. The results provide justification for the use of the plants in folk medicine to treat various infectious diseases.
{"title":"Phytochemical screening, thin-layer chromatography and antimicrobial activity study of Parquetina nigrescens leaf extracts","authors":"S. Adoga, Deborah Ehikowoicho Ekle, B. Kyenge, T. Aondo, C. Ikese","doi":"10.2478/auoc-2019-0016","DOIUrl":"https://doi.org/10.2478/auoc-2019-0016","url":null,"abstract":"Abstract Parquetina nigrescens leaves have been used in traditional medicine as an important and highly efficacious herbal remedy and have been recommended as a potential source of antimicrobial agent. Three extracts of the plant obtained using n-hexane, methanol and water were used as solvents. Phytochemical analysis of the plant extracts showed important bioactive compounds such as flavonoids, saponins, tannins, terpenes, steroids, phenols and glycosides, but alkaloids were absent in all the three extracts. Agar disk diffusion method was used to study the antimicrobial activity of the extracts at different concentrations which showed activity against three gram negative bacteria Escherichia coli, Klebsiella pneumoniae and Proteus spp., one gram positive bacteria Staphylococcus aureus, and two fungus Aspergillus flavus and Candida albicans with zone of inhibition ranging from 5-15 mm for n-hexane extract, 6-16 mm for methanol extract and 1-11 mm for aqueous extract compared to zone of inhibition for the standard antibacterial drug, 0.5 mg/mL Streptomycin that ranges from 13 – 37 mm and the zone of inhibition for the standard antifungal drug 5 mg/mL fluconazole that ranges from 24 – 25 mm. Klebsiella pneumoniae was the most inhibited while E. coli was the least inhibited by the extract, and Candida albicans was found to be resistant to the extracts in all the concentrations. TLC finger-printing of the extracts using the solvent system – butanol : acetic acid : ethanol : distilled water in the ratio 50:10:10:30 showed spots with peaks different retention times ranging from 0.24 - 0.74 cm. The results provide justification for the use of the plants in folk medicine to treat various infectious diseases.","PeriodicalId":19641,"journal":{"name":"Ovidius University Annals of Chemistry","volume":"8 1","pages":"88 - 94"},"PeriodicalIF":0.9,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72511231","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}
A. R. Osaloni, Charles O. Arijeniwa, S. Bada, Elliot O. Seyifunmi
Abstract In this study, the effect of fortification of tiger nut milk with moringa seed on the microbial, nutritional and sensory quality of the local beverage was investigated. Fortification of tiger nut milk significantly (p ≤ 0.05) reduced the fungal load of the drink with 8.00 as against 17.00 in the control sample. The organisms isolated from the freshly prepared tiger nut milk blends were Bacillus subtilis, Micrococcus luteus, Saccharomyces cerevisiae, Aspergillus niger, Rhizopus stolonifer and Penicillum species. Further, fortified milk had higher moisture (78.51%), protein (2.97%) and lipid (2.01%) contents compared with the unfortified milk which had 76.83%, 2.11% and 1.45% respectively. Also, the ash, fiber and carbohydrate contents of the unfortified tiger nut milk were higher than that of the fortified tiger nut milk. Similarly, the fortified milk had higher level of all the minerals assessed than unfortified milk. In the sensory evaluation, tiger nut milk fortified with moringa seed had comparable rating to the unfortified milk in appearance, color, consistency and acceptability, but had a lower rating for taste and higher rating for aroma. These results suggest that moringa seed powder may be added to tiger nut milk to improve its nutritional quality.
{"title":"Quality assessment of tiger nut milk fortified with Moringa oleifera seed powder","authors":"A. R. Osaloni, Charles O. Arijeniwa, S. Bada, Elliot O. Seyifunmi","doi":"10.2478/auoc-2019-0019","DOIUrl":"https://doi.org/10.2478/auoc-2019-0019","url":null,"abstract":"Abstract In this study, the effect of fortification of tiger nut milk with moringa seed on the microbial, nutritional and sensory quality of the local beverage was investigated. Fortification of tiger nut milk significantly (p ≤ 0.05) reduced the fungal load of the drink with 8.00 as against 17.00 in the control sample. The organisms isolated from the freshly prepared tiger nut milk blends were Bacillus subtilis, Micrococcus luteus, Saccharomyces cerevisiae, Aspergillus niger, Rhizopus stolonifer and Penicillum species. Further, fortified milk had higher moisture (78.51%), protein (2.97%) and lipid (2.01%) contents compared with the unfortified milk which had 76.83%, 2.11% and 1.45% respectively. Also, the ash, fiber and carbohydrate contents of the unfortified tiger nut milk were higher than that of the fortified tiger nut milk. Similarly, the fortified milk had higher level of all the minerals assessed than unfortified milk. In the sensory evaluation, tiger nut milk fortified with moringa seed had comparable rating to the unfortified milk in appearance, color, consistency and acceptability, but had a lower rating for taste and higher rating for aroma. These results suggest that moringa seed powder may be added to tiger nut milk to improve its nutritional quality.","PeriodicalId":19641,"journal":{"name":"Ovidius University Annals of Chemistry","volume":"5 1","pages":"108 - 112"},"PeriodicalIF":0.9,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78865864","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 This research was performed to ascertain the ubiquity of bacterial pathogens which hyper-produced AmpC β-lactamase enzymes in adult catfish cultured in the Nigerian catfish grow-out pond systems. Phenotypic and molecular methods were used to isolate and identify bacterial pathogens that hyper-produced AmpC β-lactamase enzymes. The AmpC β-lactamase enzymes produced by the bacterial pathogens were subsequently characterized by BLASTX and RPS-BLAST bioinformatics software as well as with the Cn3D molecular modelling software. Findings from the present study indicated that pathogenic bacterial strains which hyper-produced the AmpC β-lactamase enzymes were isolated from 49 catfish samples out of the 54 catfish samples which were examined. The pathogenic bacterial strains were mainly identified as Citrobacter freundii MGH 150, Enterobacter cloacae NG 14, and Enterobacter cloacae subspecies dissolvens HKE 15. The AmpC β-lactamase enzymes produced by the bacterial pathogens were also respectively identified as cephalosporinase hydrolyzing class C CMY-LAT-MOX-ACT-MIR-FOX, CMY2/MIR/ACT/EC family class C beta-lactamase, and CMY2/MIR/ACT/EC family class C beta-lactamase. The presence of AmpC enzymes that are hyper-produced by bacterial pathogens which were isolated from almost all the catfish examined calls for urgent monitoring/surveillance of the Nigerian catfish ponds by the relevant regulatory agencies.
摘要本研究旨在确定尼日利亚鲶鱼生长池系统养殖的成年鲶鱼中过量产生AmpC β-内酰胺酶的细菌病原体的普遍性。采用表型和分子方法分离鉴定过量产生AmpC β-内酰胺酶的细菌病原体。随后，利用BLASTX和RPS-BLAST生物信息学软件以及Cn3D分子建模软件对细菌病原体产生的AmpC β-内酰胺酶进行了表征。本研究结果表明，在54份鲶鱼样品中，从49份鲶鱼样品中分离到过量产生AmpC β-内酰胺酶的致病菌株。致病菌主要鉴定为弗氏柠檬酸杆菌MGH 150、阴沟肠杆菌ng14和阴沟肠杆菌溶解剂HKE 15。细菌病原菌产生的AmpC β-内酰胺酶也分别鉴定为头孢菌素酶水解C类cmy - lar - mox -ACT-MIR- fox、CMY2/MIR/ACT/EC家族C类β-内酰胺酶和CMY2/MIR/ACT/EC家族C类β-内酰胺酶。从几乎所有检查的鲶鱼中分离出细菌病原体过量产生的AmpC酶，这要求相关监管机构对尼日利亚鲶鱼池塘进行紧急监测/监测。
{"title":"AmpC beta-lactamase enzymes are ubiquitous in catfish (Clarias gariepinus) cultured in the Nigerian catfish grow-out pond systems","authors":"F. I. Akinnibosun, O. Imade","doi":"10.2478/auoc-2019-0005","DOIUrl":"https://doi.org/10.2478/auoc-2019-0005","url":null,"abstract":"Abstract This research was performed to ascertain the ubiquity of bacterial pathogens which hyper-produced AmpC β-lactamase enzymes in adult catfish cultured in the Nigerian catfish grow-out pond systems. Phenotypic and molecular methods were used to isolate and identify bacterial pathogens that hyper-produced AmpC β-lactamase enzymes. The AmpC β-lactamase enzymes produced by the bacterial pathogens were subsequently characterized by BLASTX and RPS-BLAST bioinformatics software as well as with the Cn3D molecular modelling software. Findings from the present study indicated that pathogenic bacterial strains which hyper-produced the AmpC β-lactamase enzymes were isolated from 49 catfish samples out of the 54 catfish samples which were examined. The pathogenic bacterial strains were mainly identified as Citrobacter freundii MGH 150, Enterobacter cloacae NG 14, and Enterobacter cloacae subspecies dissolvens HKE 15. The AmpC β-lactamase enzymes produced by the bacterial pathogens were also respectively identified as cephalosporinase hydrolyzing class C CMY-LAT-MOX-ACT-MIR-FOX, CMY2/MIR/ACT/EC family class C beta-lactamase, and CMY2/MIR/ACT/EC family class C beta-lactamase. The presence of AmpC enzymes that are hyper-produced by bacterial pathogens which were isolated from almost all the catfish examined calls for urgent monitoring/surveillance of the Nigerian catfish ponds by the relevant regulatory agencies.","PeriodicalId":19641,"journal":{"name":"Ovidius University Annals of Chemistry","volume":"33 1","pages":"25 - 28"},"PeriodicalIF":0.9,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74642743","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 The inhibition of mild steel corrosion in 1.0 M HCl and 0.5 M H2SO4 by Cissus populnea stem extract was investigated using weight loss measurements in the temperature range of 303 – 333 K. Results from the study revealed that Cissus populnea stem extract inhibited the corrosion of mild steel in both acid media. Inhibition efficiency of the stem extract increased with increase in the extract concentration but decreased with immersion time. The kinetics of the reaction aligned with a first order type. Thermodynamics investigations showed that Cissus populnea extract is adsorbed on the steel surface through physical interactions, and the adsorption process was endothermic and spontaneous. Langmuir, Freundlich and Temkin isotherm models best described the adsorption mechanism of the stem extract on the steel surface.
摘要在303 ~ 333 K的温度范围内，采用失重法研究了西芹茎提取物在1.0 M HCl和0.5 M H2SO4中对低碳钢的缓蚀作用。结果表明，西芹茎提取物对低碳钢在两种酸性介质中的腐蚀均有抑制作用。茎浸膏的抑菌率随浸膏浓度的增加而增加，但随浸膏时间的延长而降低。反应动力学符合一级反应。热力学研究表明，山茱萸提取物通过物理相互作用吸附在钢表面，吸附过程是吸热自发的。Langmuir、Freundlich和Temkin等温模型较好地描述了茎提取物在钢表面的吸附机理。
{"title":"Influence of Cissus populnea stem extract on kinetics and thermodynamics of mild steel corrosion in acidic medium","authors":"H. F. Chahul, David T. Orhemba, T. Gbadamosi","doi":"10.2478/auoc-2019-0003","DOIUrl":"https://doi.org/10.2478/auoc-2019-0003","url":null,"abstract":"Abstract The inhibition of mild steel corrosion in 1.0 M HCl and 0.5 M H2SO4 by Cissus populnea stem extract was investigated using weight loss measurements in the temperature range of 303 – 333 K. Results from the study revealed that Cissus populnea stem extract inhibited the corrosion of mild steel in both acid media. Inhibition efficiency of the stem extract increased with increase in the extract concentration but decreased with immersion time. The kinetics of the reaction aligned with a first order type. Thermodynamics investigations showed that Cissus populnea extract is adsorbed on the steel surface through physical interactions, and the adsorption process was endothermic and spontaneous. Langmuir, Freundlich and Temkin isotherm models best described the adsorption mechanism of the stem extract on the steel surface.","PeriodicalId":19641,"journal":{"name":"Ovidius University Annals of Chemistry","volume":"18 1","pages":"14 - 20"},"PeriodicalIF":0.9,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88051571","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 Application of dried plant water soluble extracts in soil Pb decontamination is rear, but advantageous due to their ecological biodegradability. Single batch laboratory scale suitability of Terminalia mantaly, Panicum maximum, Eleusine indica and water as washing solutions for Pb removal from contaminated and spiked soils at different soil pulp densities (3%, 6%, 9%, 12%, 15% and 18%) and washing time (1, 3, 6, 12, 24 and 96 h) was investigated. Washings of Terminalia mantaly and Panicum maximum proved more efficient comparatively for contaminated soil with Pb removal efficiency of 27.2±0.64% and 27.0±0.52% respectively at 3% soil pulp density and washing time of 96 h. Removal efficiency increased with increasing washing time but decreased with increasing of soil pulp density. Furthermore, water was found effective for removing Pb from spiked soils with maximum removal efficiency of 74.5±3.38% at 3% soil pulp density after 1 h washing. High exchangeable fraction of Pb (81.2%) in spiked soil makes water more suitable against other washing solutions. Statistical t-testing showed significant difference in Pb removal efficiency between contaminated and spiked soils for all four washing solutions, reflecting differences in geochemical phases of Pb in both soils. Terminalia mantaly and Panicum maximum showed promising result in soil washing and have potential for application in Pb removal from contaminated soils. However, chemical modifications are needed to enhance and improve on their efficiencies. Similarly, more information is needed to predict and model removal efficiencies when multiple washing steps are applied.
{"title":"Batch washing of lead contaminated and spiked soils using extracts of dried Terminalia mantaly, Panicum maximum and Eleusine indica plants","authors":"E. U. Etim","doi":"10.2478/auoc-2019-0006","DOIUrl":"https://doi.org/10.2478/auoc-2019-0006","url":null,"abstract":"Abstract Application of dried plant water soluble extracts in soil Pb decontamination is rear, but advantageous due to their ecological biodegradability. Single batch laboratory scale suitability of Terminalia mantaly, Panicum maximum, Eleusine indica and water as washing solutions for Pb removal from contaminated and spiked soils at different soil pulp densities (3%, 6%, 9%, 12%, 15% and 18%) and washing time (1, 3, 6, 12, 24 and 96 h) was investigated. Washings of Terminalia mantaly and Panicum maximum proved more efficient comparatively for contaminated soil with Pb removal efficiency of 27.2±0.64% and 27.0±0.52% respectively at 3% soil pulp density and washing time of 96 h. Removal efficiency increased with increasing washing time but decreased with increasing of soil pulp density. Furthermore, water was found effective for removing Pb from spiked soils with maximum removal efficiency of 74.5±3.38% at 3% soil pulp density after 1 h washing. High exchangeable fraction of Pb (81.2%) in spiked soil makes water more suitable against other washing solutions. Statistical t-testing showed significant difference in Pb removal efficiency between contaminated and spiked soils for all four washing solutions, reflecting differences in geochemical phases of Pb in both soils. Terminalia mantaly and Panicum maximum showed promising result in soil washing and have potential for application in Pb removal from contaminated soils. However, chemical modifications are needed to enhance and improve on their efficiencies. Similarly, more information is needed to predict and model removal efficiencies when multiple washing steps are applied.","PeriodicalId":19641,"journal":{"name":"Ovidius University Annals of Chemistry","volume":"2 1","pages":"29 - 36"},"PeriodicalIF":0.9,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78338902","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 This work had the objective to analyze the thermodynamic properties of cadmium doped cobalt zinc ferrite (Co0.5Zn0.5Cd0.3Fe1.8O4), obtained by solid state reaction method and characterized by TGA-DTA. The TG analysis show sharp peaks at four points, two for water reduction, one for decomposition of chlorides and last one for formation of end product. The ratio of weight of end product to starting material match with ratio of molecular weight of end product and starting materials; this confirms the formation of ferrite sample. Broido, Coats-Redfern, Chang and Horowitz-Metzger approximations are employed to compute the activation energy (Ea) of formation of ferrite sample. The kinetic parameters like frequency factor (A), entropy change (ΔS), enthalpy change (ΔH) and changes in internal energy (ΔG) of sample are also reported.
{"title":"The evaluation of kinetic parameters for cadmium doped Co-Zn ferrite using thermogravimetric analysis","authors":"A. Kulkarni, S. Mathad, Raghavendra P. Bakale","doi":"10.2478/auoc-2019-0011","DOIUrl":"https://doi.org/10.2478/auoc-2019-0011","url":null,"abstract":"Abstract This work had the objective to analyze the thermodynamic properties of cadmium doped cobalt zinc ferrite (Co0.5Zn0.5Cd0.3Fe1.8O4), obtained by solid state reaction method and characterized by TGA-DTA. The TG analysis show sharp peaks at four points, two for water reduction, one for decomposition of chlorides and last one for formation of end product. The ratio of weight of end product to starting material match with ratio of molecular weight of end product and starting materials; this confirms the formation of ferrite sample. Broido, Coats-Redfern, Chang and Horowitz-Metzger approximations are employed to compute the activation energy (Ea) of formation of ferrite sample. The kinetic parameters like frequency factor (A), entropy change (ΔS), enthalpy change (ΔH) and changes in internal energy (ΔG) of sample are also reported.","PeriodicalId":19641,"journal":{"name":"Ovidius University Annals of Chemistry","volume":"184 ","pages":"60 - 64"},"PeriodicalIF":0.9,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72424743","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：