Eggplant Lipoxygenase (Solanummelongena):  Product Characterization and Effect of Physicochemical Properties of Linoleic Acid on the Enzymatic Activity

2001 ◽  
Vol 49 (1) ◽  
pp. 433-438 ◽  
Author(s):  
José Manuel López-Nicolás ◽  
Manuela Pérez-Gilabert ◽  
Francisco García-Carmona
Keyword(s):  
Linoleic Acid ◽  
Enzymatic Activity ◽  
Physicochemical Properties ◽  
Product Characterization

Effect of linoleic acid infusion on blood pressure in normotensive and hypertensive rats

1989 ◽  
Vol 257 (2) ◽  
pp. H611-H617 ◽  
Author(s):  
S. R. Reddy ◽  
R. Talwalkar ◽  
J. Downs ◽  
T. A. Kotchen
Keyword(s):  
Blood Pressure ◽  
Linoleic Acid ◽  
Sodium Chloride ◽  
Enzymatic Activity ◽  
Plasma Renin ◽  
Sprague Dawley ◽  
Acid Infusion ◽  
High Sodium ◽  
Hypotensive Response

High dietary intake of linoleic acid lowers arterial pressure, and, in vitro, linoleic acid inhibits the enzymatic activity of renin. The purpose of the present study was 1) to evaluate the effect of intravenous infusion of linoleic acid on blood pressure in normotensive and hypertensive Sprague-Dawley rats and 2) to determine whether the hypotensive response to linoleic acid infusion is caused by inhibition of circulating renin. Blood pressure was decreased (P less than 0.01) by linoleic acid infusion in normotensive sodium chloride-deprived animals and in animals with two-kidney, one-clip hypertension. In contrast, linoleic acid infusion did not affect blood pressure in normotensive rats on a "normal" or high sodium chloride intake, in rats with deoxycorticosterone acetate (DOCA)-salt hypertension, and in anephric rats. In sodium chloride-deprived rats, the reduction of blood pressure by linoleic acid infusion was associated with increased plasma renin activity (P less than 0.05); serum angiotensin-converting enzyme activity was unchanged. The in vitro enzymatic activity of exogenous renin in plasma of anephric rats was not affected by linoleic acid infusion. In two-kidney, one-clip hypertensive animals, pretreatment with indomethacin did not alter the hypotensive response to linoleic acid. Thus, although linoleic acid infusion lowered blood pressure in high renin but not in low renin states, the reduction of blood pressure was not related to inhibition of circulating renin or to alterations of endogenous prostaglandin biosynthesis.

scholarly journals Enhancing the Lubricity of Gas-to-Liquid (GTL) Paraffinic Kerosene: Impact of the Additives on the Physicochemical Properties

2020 ◽  
Author(s):  
Hani Ababnah ◽  
Nasr Mohamed ◽  
Hanif Choudhury ◽  
Lei Lei Zhang ◽  
Rafiqul Gani ◽  
...  
Keyword(s):  
Linoleic Acid ◽  
Physicochemical Properties ◽  
Negative Impact ◽  
Freezing Point ◽  
Ethyl Oleate ◽  
Heat Content ◽  
Wear Scar Diameter ◽  
Dual Nature ◽  
Fuel Jet ◽  
High Concentrations

Abstract Synthetic paraffinic kerosene (SPK) is an ultra-clean fuel with low aromatic content and negligible quantities of sulfur compounds . Although, SPK has a good potential to replace the conventional fuel Jet A-1 , it also has some deficiencies. One of them is the low lubricity compared to its conventional counterpart Jet A-1. To improve the lubricity of SPK, three selected additives have been mixed with SPK at different concentrations. The lubricity of the samples was determined experimentally and the samples that meet the industry specifications have been studied further. The effect of the additives on the physicochemical properties, such as, density, flash point, freezing point, viscosity, and heat content, were investigated. Linoleic acid was found to be an excellent lubricity improver even at a very low concentration and its negative impact on the other physicochemical properties was found to be insignificant. Ethyl oleate also demonstrated significant improvement in lubricity at low concentrations but had a negative impact on the fuel’s freezing point at high concentrations. Quinoline, at high concentrations, elevated the blend’s freezing point above the acceptable limits. In parallel to the experimental campaign, a pre-existing mathematical modelling tool was utilized to predict the properties of interest. The lubricity model was successfully introduced into the mathematical model in order to improve the capabilities of the model. Linoleic acid sample showed the best improvement in lubricity of SPK with wear scar diameter of 4 17 μm; well below the ASTM D7566 maximum limit of 850µm. The dual nature of this study facilitated the optimization of the physicochemical properties of the fuel samples.

scholarly journals Estimation of Various Physicochemical Properties of Walnut Oil from Different Areas of Northern Kpk, Pakistan

2021 ◽  
Vol 65 (4) ◽  
Author(s):  
Yasir Uddin ◽  
Nasir Mehmood Khan ◽  
Farman Ali ◽  
Shujaat Ahamd ◽  
Zia Ullah Khan ◽  
...  
Keyword(s):  
Surface Tension ◽  
Oleic Acid ◽  
Linoleic Acid ◽  
Physicochemical Properties ◽  
Olive Oil ◽  
Food Processing ◽  
Juglans Regia ◽  
Acid Value ◽  
Walnut Oil ◽  
Iodine Values

Abstract. In this study, the physicochemical properties of walnut (Juglans regia L.) oils collected from different sites in Khyber PakhtoonKhwa (KPK), Pakistan were investigated. The obtained walnut oils showed variation in viscosity, surface tension, density, acid, saponification, and iodine values. The oil obtained from the Madyan (Sample E) showed the lowest density (0.981 g/cm3), surface tension (34.76×10-3 N/m), viscosity (15.0595 cp) saponification values 84.15 (mg KOH/g of oil) and acid value 3.5 (mg KOH per gram oil) amongst all. The physicochemical properties of all the oils were also compared to olive oil (standard) where sample E showed similarities in such properties compared to olive oil. Moreover, higher concentrations of oleic acid (41 %) and linoleic acid (9 %) were detected in the walnut oil of sample E in GC/MS analysis. The similarities of walnut oil obtained from Madyan to that of standard (olive oil) thus affirm it as best quality oil and suitable for food processing purposes.      Resumen. En este estudio se investigaron las propiedades fisicoquímicas del aceite de nuez (Juglans regia L.) recolectado de diferentes sitios en Khyber PakhtoonKhwa (KPK), Pakistán. Los aceites de nuez obtenidos mostraron variación en los valores de viscosidad, tensión superficial, densidad, acidez, saponificación e índice de yodo. El aceite obtenido del Madyan (Muestra E) mostró la menor densidad (0.981 g/cm3), tensión superficial (34.76 × 10-3 N/m), viscosidad (15.0595 cp), valores de saponificación 84.15 (mg KOH/g de aceite) y valor ácido 3.5 (mg KOH por gramo de aceite) entre otros. Las propiedades fisicoquímicas de todos los aceites también se compararon con el aceite de oliva (estándar); la muestra E mostró similitudes en las diferentes propiedades en comparación con el aceite de oliva. Además, se determinaron concentraciones más elevadas de ácido oleico (41 %) y ácido linoleico (9 %) en el aceite de nuez de la muestra E mediante el análisis GC/MS. Las similitudes del aceite de nuez obtenido de Madyan con el estándar (aceite de oliva) lo afirman como aceite de mejor calidad y adecuado para el procesamiento de alimentos.

The role of an urban park's tree stand in shaping the enzymatic activity, glomalin content and physicochemical properties of soil

2020 ◽  
Vol 741 ◽  
pp. 140446 ◽  
Author(s):  
Joanna Lemanowicz ◽  
Samir A. Haddad ◽  
Agata Bartkowiak ◽  
Robert Lamparski ◽  
Piotr Wojewódzki
Keyword(s):  
Enzymatic Activity ◽  
Physicochemical Properties ◽  
Tree Stand ◽  
Properties Of Soil

scholarly journals Enhancing the Lubricity of Gas-to-Liquid (GTL) Paraffinic Kerosene: Impact of the Additives on the Physicochemical Properties

2020 ◽  
Author(s):  
Hani Ababnah ◽  
Nasr Mohamed ◽  
Hanif Choudhury ◽  
Lei Lei Zhang ◽  
Rafiqul Gani ◽  
...  
Keyword(s):  
Linoleic Acid ◽  
Physicochemical Properties ◽  
Negative Impact ◽  
Freezing Point ◽  
Ethyl Oleate ◽  
Heat Content ◽  
Wear Scar Diameter ◽  
Dual Nature ◽  
Fuel Jet ◽  
High Concentrations

Abstract Synthetic paraffinic kerosene (SPK) is an ultra-clean fuel with low aromatic content and negligible quantities of sulfur compounds. Although, SPK has a good potential to replace the conventional fuel Jet A-1, it also has some deficiencies. One of them is the low lubricity compared to its conventional counterpart Jet A-1. To improve the lubricity of SPK, three selected additives have been mixed with SPK at different concentrations. The lubricity of the samples was determined experimentally and the samples that meet the industry specifications have been studied further. The effect of the additives on the physicochemical properties, such as, density, flash point, freezing point, viscosity, and heat content, were investigated. Linoleic acid was found to be an excellent lubricity improver even at a very low concentration and its negative impact on the other physicochemical properties was found to be insignificant. Ethyl oleate also demonstrated significant improvement in lubricity at low concentrations but had a negative impact on the fuel’s freezing point at high concentrations. Quinoline, at high concentrations, elevated the blend’s freezing point above the acceptable limits. In parallel to the experimental campaign, a pre-existing mathematical modelling tool was utilized to predict the properties of interest. The lubricity model was successfully introduced into the mathematical model in order to improve the capabilities of the model. Linoleic acid sample showed the best improvement in lubricity of SPK with wear scar diameter of 417 µm; well below the ASTM D7566 maximum limit of 850 µm. The dual nature of this study facilitated the optimization of the physicochemical properties of the fuel samples.

scholarly journals The effect of drinking milk containing conjugated linoleic acid on fecal microbiological profile, enzymatic activity, and fecal characteristics in humans

2007 ◽  
Vol 6 (1) ◽  
Author(s):  
Edward R Farnworth ◽  
Yvan P Chouinard ◽  
Helene Jacques ◽  
Sudha Venkatramanan ◽  
Akier A Maf ◽  
...  
Keyword(s):  
Linoleic Acid ◽  
Enzymatic Activity ◽  
Conjugated Linoleic Acid ◽  
Microbiological Profile ◽  
Drinking Milk

Physicochemical properties and digestion mechanism of starch-linoleic acid complex induced by multi-frequency power ultrasound

2021 ◽  
pp. 130392
Author(s):  
Husnain Raza ◽  
Kashif Ameer ◽  
Xiaofeng Ren ◽  
Qiufang Liang ◽  
Xinxiang Chen ◽  
...  
Keyword(s):  
Linoleic Acid ◽  
Physicochemical Properties ◽  
Acid Complex ◽  
Power Ultrasound ◽  
Frequency Power

scholarly journals Studying the Physicochemical Properties and Isolation of Unsaturated Fatty Acids from Edible Oils by GC-MS and Argentated Silica Gel Chromatography

2021 ◽  
pp. 346-362
Author(s):  
Salim Najmaldain Saber ◽  
Hikmat Ali Mohamad ◽  
Madzlan Aziz
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Methyl Ester ◽  
Physicochemical Properties ◽  
Olive Oil ◽  
Unsaturated Fatty Acids ◽  
Acid Methyl Ester ◽  
Acid Methyl

The core objective of this study was to investigate the physicochemical characteristics and fatty acid composition of the oils of sunflower, olive, virgin coconut and ginger oils, as well as the separation of their unsaturated fatty acids. The data indicated a significant variation in physicochemical properties (acid, saponification, ester, and iodine values) among oils. Transesterification process was carried out at a molar ratio of 1:7:0.1 of oil: methanol: KOH. Fatty acid methyl esters of oils were analyzed by infrared (IR) and gas chromatography–mass (GC-MS) spectrometry. Twelve fatty acids were identified, where the major fatty acid of  olive oil was found to be  oleic acid (89%), whereas those of sunflower and ginger oils were linoleic acid (80.9 %) and (79.3 %), respectively. Sunflower and olive oils were fractionated by 25% silver nitrate-impregnated silica gel column chromatography. By this method, linoleic acid methyl ester from sunflower and oleic acid methyl ester from olive oil were isolated with high purity percentages and yields. This study is significant for the development of food and pharmaceutical products.

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