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1

Photochemical screening and corrosion inhibition of Poupartia birrea back extracts as a potential green inhibitor for mild steel in 0.5 M H2SO4 medium

100%

Louis H., Japari J., Sadia A., Philip M., Bamanga A.

World News of Natural Sciences

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2017

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vol. 10

95-100

EN

Corrosion of metals is a serious environmental problem and has been given much attention in the oil and gas industries. In several industrial processes (acid cleaning and etching, removal of rust and scale), metal surfaces are often made to come in contact with acids. In the present study, an attempt was made to examine Poupartia birrea (P. birres) back extract as a potential green corrosion inhibitor for mild steel in a 0.5 M H2SO4 medium, using the weight loss determination method. The results of our work indicate that highest inhibition efficiency exhibited by Poupartia birrea is 70%. The inhibiting effect of the studied extract could be attributed to the presence of phytochemical constituents present in the extract that are adsorbed on the surface of the mild steel. The plant extract can, hence, be considered as being eco-friendly and an effective green corrosion inhibitor for mild steel exposed to an acid medium.

2

Inhibitors of bacterial and plants urease. A review

88%

Macegoniuk K.

Acta Universitatis Lodziensis. Folia Biologica et Oecologica

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2013

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vol. 9

9-16

EN

Urease is an important virulence factor for Helicobacter pylori and Proteus mirabilis as well as in environmental transformations of certain nitrogenous compounds. Urea hydrolysis caused by these microorganisms leads to increased pH and ammonia toxicity and enables bacterial colonization of the human gastric mucosa and urinary tract formation of struvite and carbonate-apatite stones. Due to the possibility of medical applications the development of novel, selective and efficient classes of urease inhibitors which satisfy the low toxicity requirement for human health and have low environmental impact is necessary. In this article are described the various urease inhibitors used so far by researchers, especially in the last few years.

3

Investigating the extract constituents and corrosion inhibiting ability of Sida acuta leaves

88%

Adindu Chinonso B., Oguzie Emeka E.

World News of Natural Sciences

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2017

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vol. 13

63-81

EN

Constituents of the ethanol extract of Sida acuta (SA) leaves were investigated by phytochemical, GC-MS and FTIR studies and its corrosion inhibition effects on mild steel was studied in 1 M HCl and 0.5 M H2SO4 solutions, using gravimetric and electrochemical methods of corrosion monitoring. The surface morphology of the mild steel surface before and after corrosion was also assessed using SEM imaging. The phytochemical, GC-MS and FTIR results revealed that SA contains carbonyl groups, aromatic rings, and double bonds that make it a prospective corrosion inhibitor for mild steel. Moreover, gravimetric results indicated that SA is an effective additive for the corrosion of mild steel at all the concentrations studied. Finally, the electrochemical results showed that SA inhibited both the anodic and cathodic half reactions by the adsorption of the extract constituents on the mild steel surface; this was further confirmed by the SEM investigations.

4

Computational design of novel cyclic urea as HIV-1 protease inhibitor

88%

Vijjulatha M., Kanth S.

Open Chemistry

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2007

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vol. 5

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issue 4

1064-1072

EN

A series of novel cyclic urea molecules 5,6-dihydroxy-1,3-diazepane-2,4,7-trione as HIV-1 protease inhibitors were designed using computational techniques. The designed molecules were compared with the known cyclic urea molecules by performing docking studies, calculating their ADME (Absorption, Distribution, Metabolism, and Excretion) properties and protein ligand interaction energy. These novel molecules were designed by substituting the P 1/P′ 1 positions (4th and 7th position of 1, 3-diazepan-2-one) with double bonded oxygens. This reduces the molecular weight and increases the bioavailability, indicating better ADME properties. The docking studies showed good binding affinity towards HIV-1 protease. The biological activity of these inhibitors were predicted by a model equation generated by the regression analysis between biological activity (log 1/K i ) of known inhibitors and their protein ligand interaction energy. The synthetic studies are in progress. [...]

5

rapid detection for the inhibition of phosphoglucose isomerase from Escherichia coli by mercury(II) chloride based on TLC-autographic analysis – preliminary studies

88%

Paradowska K., Lutek J., Ginalska G.

Current Issues in Pharmacy and Medical Sciences

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2014

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vol. 27

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issue 2

127-130

EN

The quest for new techniques for screening inhibitors of phosphoglucose isomerase is crucially important owing to therapeutic control of chronic bacterial infections associated with the biosynthesis of bacterial biofilm. According to the new method, yellowish zones against the purple background could be visually observed where phosphoglucose isomerase activity was inhibited. The new protocol with NADPH/NBT/PMS staining for TLC-autographic method was able to detect PGI inhibition by pure reference substance as mercury(II) chloride.

6

Optimization of corrosion inhibition of Picralima nitida leaves extract as green corrosion inhibitor for zinc in 1.0 M HCl

88%

Ezeugo J. N. O., Onukwuli O. D., Omotioma M.

World News of Natural Sciences

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2017

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vol. 15

139-161

EN

Herein, the optimization of inhibitive action of the ethanol extract of oil from Picralima nitida leaves, towards acid corrosion of zinc, was tested using weight loss and thermometry methods. We found that the extract acts as a good corrosion inhibitor for zinc corrosion in 0.1 M HCl solutions. The inhibition action of the extract was discussed in view of Langmuir adsorption isotherm. This revealed that spontaneous processes govern the adsorption of the extract on zinc surface. Herein, the inhibition efficiency (IE) increases in line with corresponding increase in extract concentration. The temperature effect of the corrosion inhibition on the IE was also studied. This indicated that the presence of the extract increases the needed activation energy of the corrosion reaction. Furthermore, in our work, an optimal inhibition efficiency IE (%) of 86.78 was obtained at optimum inhibitor concentration of 1.2 gl-1, optimum temperature and time of 313 k and 8 hrs, respectively. From the calculated thermodynamic parameters, it can be said, then, that Picralima nitida extract provides good protection to zinc against pitting corrosion in chloride ion containing solutions.

7

Trypsin-specific Inhibitors from the Macrolepiota procera, Armillaria mellea and Amanita phalloides wild mushrooms

75%

Lukanc T., Brzin J., Kos J., Sabotič J.

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2017

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vol. 64

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issue 1

21-24

EN

Wild growing mushrooms are a rich source of novel proteins with unique features. We have isolated and characterized trypsin inhibitors from two edible mushrooms, the honey fungus (Armillaria mellea) and the parasol mushroom (Macrolepiota procera), and from the poisonous death cap (Amanita phalloides). The trypsin inhibitors isolated: armespin, macrospin and amphaspin, have similar molecular masses, acidic isoelectric points and are not N-glycosylated. They are very strong trypsin inhibitors and weak chymotrypsin inhibitors. They are resistant to exposure to high temperatures and withstand extreme pH values. These exceptional characteristics are advantageous for their potential use in biotechnology, agriculture and medicine.

8

Sclerotherapy of esophageal varices in severe hemophilia a patient and high titer inhibitor – case report

75%

Szczepanik A., Dąbrwski W., Szczepaniak A., Pielaciński K., Jaśkowiak W.

Polish Journal of Surgery

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2015

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vol. 87(9)

464-468

EN

In cirrhotic hemophilia patients bleeding from esophageal varices is a serious clinical condition due to congenital deficiency of clotting factors VIII or IX, decreased prothrombin synthesis and hypersplenic thrombocytopenia. In hemophiliac with high-titer inhibitor bypassing therapy is required with activated prothrombin complex concentrates (aPCC) or recombinant activated coagulation factor VII (rFVIIa). Doses and duration treatment with these agents following endoscopic treatment of esophageal varices have not been yet established. Authors report the first case of a severe hemophilia A patient with high titer inhibitor (40 BU) treated with repeated injection sclerotherapy. The patient was admitted with symptoms of massive esophageal variceal hemorrhage ceased with emergency sclerotherapy. Bypassing therapy was administered with aPCC at initial dose of 72.5 U/kg and then with average daily dose of 162 U/kg through 5 days. To achieved a total eradication of esophageal varices the patient was then subjected to four elective sclerotherapy procedures. Two were covered by aPCC with daily dose of 120 U/kg and 145 U/kg for 4 and 3 days respectively and the following two procedures were covered by rFVIIa with the initial dose of 116 µg/kg and the next doses of 87 µg/kg administered every 3 hours in procedure day and every 4 hours on the next two days. During all procedures excellent hemostasis was achieved and no hemorrhagic or thromboembolic complications were observed. Bypassing regimen therapy with aPCC and rFVIIa we applied have been shown to be safe and effective in this patient subjected to sclerotherapy procedures.

9

The use of ammonium sulfate as an inhibitor of dioxin synthesis in iron ore sintering process

71%

Łechtańska P., Wielgosiński G.

Ecological Chemistry and Engineering S

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2014

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vol. 21

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issue 1

59-70

EN

The main air pollutants in the sintering process of iron ore are polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs) and harmful dust. Ore sintering on sinter strands is one of the first technology steps in the ironworks. It is a process in which iron ore is crushed, subjected to annealing and mixed with appropriate additives, and then sintered in order to produce sinter which is the main component of iron in the blast furnace process. PCDD/Fs emissions were measured and the addition of ammonium sulfate as an inhibitor of the synthesis of dioxins in the sintering process of iron ore was studied.

PL

Do głównych substancji zanieczyszczających powietrze w procesie spiekania rud żelaza należą polichlorowane dibenzodioksyny i polichlorowane dibenzofurany (PCDD/PCDF), a także szkodliwe pyły. Spiekanie rud na taśmach jest jednym z pierwszych węzłów technologicznych huty o profilu surowcowym. Jest to proces, w którym ruda żelaza jest kruszona, poddawana wyżarzaniu i mieszana z odpowiednimi dodatkami, a następnie spiekana w celu otrzymania spieku, który stanowi główny składnik żelazowy w procesie wielkopiecowym. W aglomerowni wykonano pomiary emisji PCDD/Fs, a także badano dodatek siarczanu amonu jako inhibitora syntezy dioksyn w procesie spiekania rudy żelaza.

Refine search results

Photochemical screening and corrosion inhibition of Poupartia birrea back extracts as a potential green inhibitor for mild steel in 0.5 M H2SO4 medium

Inhibitors of bacterial and plants urease. A review

Investigating the extract constituents and corrosion inhibiting ability of Sida acuta leaves

Computational design of novel cyclic urea as HIV-1 protease inhibitor

rapid detection for the inhibition of phosphoglucose isomerase from Escherichia coli by mercury(II) chloride based on TLC-autographic analysis – preliminary studies

Optimization of corrosion inhibition of Picralima nitida leaves extract as green corrosion inhibitor for zinc in 1.0 M HCl

Trypsin-specific Inhibitors from the Macrolepiota procera, Armillaria mellea and Amanita phalloides wild mushrooms

Sclerotherapy of esophageal varices in severe hemophilia a patient and high titer inhibitor – case report

The use of ammonium sulfate as an inhibitor of dioxin synthesis in iron ore sintering process