scholarly journals Hydrolysis of Some of The Common Vegetable Oils*

1916 ◽  
Vol 5 (2) ◽  
pp. 170-174
Author(s):  
W.F. Rudd
Keyword(s):  
Vegetable Oils ◽  
The Common ◽  
Hydrolysis Of

scholarly journals Kinetic probes for inter-domain co-operation in human somatic angiotensin-converting enzyme

2005 ◽  
Vol 391 (3) ◽  
pp. 641-647 ◽  
Author(s):  
Olga E. Skirgello ◽  
Peter V. Binevski ◽  
Vladimir F. Pozdnev ◽  
Olga A. Kost
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Enzymatic Activity ◽  
Active Site ◽  
The Other ◽  
Converting Enzyme ◽  
Human Enzyme ◽  
Independent Functions ◽  
The Common ◽  
The Individual ◽  
Hydrolysis Of

s-ACE (the somatic form of angiotensin-converting enzyme) consists of two homologous domains (N- and C-domains), each bearing a catalytic site. Negative co-operativity between the two domains has been demonstrated for cow and pig ACEs. However, for the human enzyme there are conflicting reports in the literature: some suggest possible negative co-operativity between the domains, whereas others indicate independent functions of the domains within s-ACE. We demonstrate here that a 1:1 stoichiometry for the binding of the common ACE inhibitors, captopril and lisinopril, to human s-ACE is enough to abolish enzymatic activity towards FA {N-[3-(2-furyl)acryloyl]}-Phe-GlyGly, Cbz (benzyloxycarbonyl)-Phe-His-Leu or Hip (N-benzoylglycyl)-His-Leu. The kinetic parameters for the hydrolysis of seven tripeptide substrates by human s-ACE appeared to represent average values for parameters obtained for the individual N- and C-domains. Kinetic analysis of the simultaneous hydrolysis of two substrates, Hip-His-Leu (S1) and Cbz-Phe-His-Leu (S2), with a common product (His-Leu) by s-ACE at different values for the ratio of the initial concentrations of these substrates (i.e. σ=[S2]0/[S1]0) demonstrated competition of these substrates for binding to the s-ACE molecule, i.e. binding of a substrate at one active site makes the other site unavailable for either the same or a different substrate. Thus the two domains within human s-ACE exhibit strong negative co-operativity upon binding of common inhibitors and in the hydrolysis reactions of tripeptide substrates.

Angiotensin converting enzyme in brush-border membranes of avian small intestine

1988 ◽  
Vol 135 (1) ◽  
pp. 1-8
Author(s):  
B. R. Stevens ◽  
A. Fernandez ◽  
C. del Rio Martinez
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Brush Border ◽  
Physiological Role ◽  
Intestinal Epithelial ◽  
Converting Enzyme ◽  
Brush Border Membranes ◽  
Fluid Uptake ◽  
The Common ◽  
Kinetics Of ◽  
Hydrolysis Of

Angiotensin converting enzyme activity was identified in brush-border membranes purified from the small intestinal epithelium of the common grackle, Quiscalus quiscula. Angiotensin converting enzyme was enriched 20-fold in the membrane preparation, compared with intestinal epithelial cell scrapes, and was coenriched with the brush-border markers, alkaline phosphatase and aminopeptidase N. The kinetics of hydrolysis of N-[3-(2-furyl)acryloyl]-L-phenylalanylglycylglycine (FAPGG) gave a Vmax of 907 +/− 41 units g-1 and a Km of 55 +/− 6 mumol l-1. The avian intestinal angiotensin converting enzyme was inhibited by the antihypertensive drug, Ramipril, with a median inhibitory concentration (IC50) of 1 nmol l-1. In the light of previous studies on angiotensin converting enzyme in mammalian epithelia, these results may implicate a physiological role for angiotensin converting enzyme in regulating electrolyte and fluid uptake in bird small intestines.

scholarly journals Overcoming insecticide resistance through computational inhibitor design

2019 ◽  
Vol 116 (42) ◽  
pp. 21012-21021 ◽  
Author(s):  
Galen J. Correy ◽  
Daniel Zaidman ◽  
Alon Harmelin ◽  
Silvia Carvalho ◽  
Peter D. Mabbitt ◽  
...  
Keyword(s):  
Boronic Acid ◽  
High Selectivity ◽  
Agricultural Pests ◽  
Potato Aphid ◽  
Global Food Security ◽  
Evolution Of Resistance ◽  
The Common ◽  
Hydrolysis Of ◽  
Peach Potato Aphid ◽  
Global Food

Insecticides allow control of agricultural pests and disease vectors and are vital for global food security and health. The evolution of resistance to insecticides, such as organophosphates (OPs), is a serious and growing concern. OP resistance often involves sequestration or hydrolysis of OPs by carboxylesterases. Inhibiting carboxylesterases could, therefore, restore the effectiveness of OPs for which resistance has evolved. Here, we use covalent virtual screening to produce nano-/picomolar boronic acid inhibitors of the carboxylesterase αE7 from the agricultural pest Lucilia cuprina as well as a common Gly137Asp αE7 mutant that confers OP resistance. These inhibitors, with high selectivity against human acetylcholinesterase and low to no toxicity in human cells and in mice, act synergistically with the OPs diazinon and malathion to reduce the amount of OP required to kill L. cuprina by up to 16-fold and abolish resistance. The compounds exhibit broad utility in significantly potentiating another OP, chlorpyrifos, against the common pest, the peach–potato aphid (Myzus persicae). These compounds represent a solution to OP resistance as well as to environmental concerns regarding overuse of OPs, allowing significant reduction of use without compromising efficacy.

Application of Benzyl Ester of Modified Vegetable Oils as Rubber Processing Oils

2011 ◽  
Vol 415-417 ◽  
pp. 1164-1167 ◽  
Author(s):  
Hasleena Boontawee ◽  
Charoen Nakason ◽  
Azizon Kaesaman ◽  
Anoma Thitithammawong ◽  
Sopa Chewchanwuttiwong
Keyword(s):  
Fatty Acids ◽  
Vegetable Oils ◽  
Dynamic Mechanical Properties ◽  
Benzyl Ester ◽  
Molar Ratio ◽  
Mixing Energy ◽  
Rubber Compounds ◽  
Different Types ◽  
Benzyl Esters ◽  
Hydrolysis Of

Benzyl esters of fatty acids based on three types of vegetable oils (i.e., coconut, palm, and soybean oils) were in-house prepared. They were used as alternative rubber processing oil to replace conventional aromatic oil which has been banned by European community since December 2009. Fatty acids were first prepared by hydrolysis of vegetable oils and thereafter esterified with benzyl alcohol in the presence of sulfuric acid as a catalyst. The reaction based on molar ratio of fatty acid:benzyl alcohol:sulfuric acid was set at 1.5:1.0:0.05 gave yield of benzyl esters higher than 80%. Rubber compounds containing different types of benzyl ester were prepared according to the standard formulation of ASTM 3184. It was found that the processing oil in the form of benzyl esters is possible to use instead of aromatic oil in rubber formulation. Various parameters and properties include mixing energy, Mooney viscosity, curing, mechanical and dynamic mechanical properties of rubber compounds and vulcanizates have been investigated.

The Reduction in the Rate of Hydrolysis of Diphenylbromomethane by the Common-Ion Effect

2010 ◽  
Vol 87 (8) ◽  
pp. 848-849
Author(s):  
Richard Cameron-Holford ◽  
Tarini Ratneswaren ◽  
D. E. Peter Hughes
Keyword(s):  
Common Ion ◽  
Rate Of Hydrolysis ◽  
The Common ◽  
Common Ion Effect ◽  
Hydrolysis Of

scholarly journals Overcoming insecticide resistance through computational inhibitor design

2017 ◽  
Author(s):  
Galen J. Correy ◽  
Daniel Zaidman ◽  
Alon Harmelin ◽  
Silvia Carvalho ◽  
Peter D. Mabbitt ◽  
...  
Keyword(s):  
High Selectivity ◽  
Computational Design ◽  
Agricultural Pests ◽  
Potato Aphid ◽  
Global Food Security ◽  
Evolution Of Resistance ◽  
The Common ◽  
Hydrolysis Of ◽  
Peach Potato Aphid ◽  
Global Food

AbstractInsecticides allow control of agricultural pests and disease vectors and are vital for global food security and health. The evolution of resistance to insecticides, such as organophosphates (OPs), is a serious and growing concern. OP resistance often involves sequestration or hydrolysis of OPs by carboxylesterases. Inhibiting carboxylesterases could therefore restore the effectiveness of OPs for which resistance has evolved. Here, we use covalent computational design to produce nano/pico-molar boronic acid inhibitors of the carboxylesterase αE7 from the agricultural pest Lucilia cuprina, as well as a common Gly137Asp αE7 mutant that confers OP resistance. These inhibitors, with high selectivity against human acetylcholinesterase, and low to no toxicity in human cells and mice, act synergistically with the OPs diazinon and malathion to reduce the amount of OP required to kill L. cuprina by up to 16-fold, and abolish resistance. The compounds exhibit broad utility in significantly potentiating another OP, chlorpyrifos against the common pest, the peach-potato aphid (Myzus persicae). These compounds represent a solution to OP resistance as well as to environmental concerns regarding overuse of OPs, allowing significant reduction of use without compromising efficacy.

scholarly journals A Direct Silanization Protocol for Dialdehyde Cellulose

Molecules ◽  
2020 ◽  
Vol 25 (10) ◽  
pp. 2458 ◽  
Author(s):  
Arianna Lucia ◽  
Markus Bacher ◽  
Hendrikus W. G. van Herwijnen ◽  
Thomas Rosenau
Keyword(s):  
Aqueous Media ◽  
Hydroxyl Group ◽  
Cross Linking ◽  
Cellulose Derivatives ◽  
Reaction Conditions ◽  
Cellulose Structure ◽  
Dialdehyde Cellulose ◽  
Potential Applications ◽  
The Common ◽  
Hydrolysis Of

Cellulose derivatives have many potential applications in the field of biomaterials and composites, in addition to several ways of modification leading to them. Silanization in aqueous media is one of the most promising routes to create multipurpose and organic–inorganic hybrid materials. Silanization has been widely used for cellulosic and nano-structured celluloses, but was a problem so far if to be applied to the common cellulose derivative “dialdehyde cellulose” (DAC), i.e., highly periodate-oxidized celluloses. In this work, a straightforward silanization protocol for dialdehyde cellulose is proposed, which can be readily modified with (3-aminopropyl)triethoxysilane. After thermal treatment and freeze-drying, the resulting product showed condensation and cross-linking, which was studied with infrared spectroscopy and 13C and 29Si solid-state nuclear magnetic resonance (NMR) spectroscopy. The cross-linking involves both links of the hydroxyl group of the oxidized cellulose with the silanol groups (Si-O-C) and imine-type bonds between the amino group and keto functions of the DAC (-HC=N-). The modification was achieved in aqueous medium under mild reaction conditions. Different treatments cause different levels of hydrolysis of the organosilane compound, which resulted in diverse condensed silica networks in the modified dialdehyde cellulose structure.

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