Search results for " Oil"
showing 10 items of 1049 documents
Sesquiterpene lactones, waxes and volatile compounds from Artemisia herba-alba subspecies Valentina
1979
Abstract The structures of two sesquiterpene lactones isolated from Artemisia herba-alba subsp. valentina have been determined by spectroscopic methods. One of these was dihydroreynosin, the other was a new compound assigned the name torrentin. The chemical compositions of a wax and a hydrocarbon fraction from the essential oil have also been investigated.
Revisiting delta-6 desaturase regulation by C18 unsaturated fatty acids, depending on the nutritional status.
2009
Dietary polyunsaturated fatty acids (PUFA) play a key role in regulating delta-6 desaturase (D6D), the key enzyme for long-chain PUFA biosynthesis. Nevertheless, the extent of their effects on this enzyme remains controversial and difficult to assess. It has been generally admitted that C18 unsaturated fatty acids (UFAs) regulate negatively delta-6 desaturase (D6D). This inhibition has been evidenced in regard to a high glucose/fat free (HG/FF) diet used in reference. However, several nutritional investigations did not evidence any inhibition of desaturases when feeding fatty acids. Because the choice of the basal diet appeared to be of primary importance in such experiments, our goal was t…
Water-Blown Polyisocyanurate Foams From Vegetable Oil Polyols
2008
Polyols with the hydroxyl value OHV from 290 to 318 mg KOH/g are synthesized from rapeseed, sunflower seed, flaxseed, or coconut oils by the way of their: (1) transesterification with triethanolamine or (2) amidization with diethanolamine. The influence of water as the blowing agent on the storage stability of the polyol premix system is assessed from values of the polyol premix system pH, acid value, and variations in such parameters as cream and gel time. Water-blown polyisocyanurate (PIR) foams (150 · II × 300; II—isocyanate index) characterized by good mechanical characteristics, dimensional stability at 70°C and at relative humidity RH = 95% as well as by a very low water absorbance, …
Utilization of different dietary lipid sources at high level in herbivorous grass carp (Ctenopharyngodon idella): mechanism related to hepatic fatty …
2008
Herbivorous grass carp (Ctenopharyngodon idella) has been reported to exhibit low capacity to utilize high dietary lipid, but different lipid sources might affect this limited capacity. In order to compare the effects of different lipid sources with different lipid levels, juvenile grass carp were fed one of nine diets containing three oils [lard, plant oil mixed by maize and linseed oil, and n-3 high unsaturated fatty acid-enriched (HUFA-enriched) fish oil] at three lipid levels (20, 60 and 100 g kg(-1) dry diet) for 8 weeks. Decreased feed intake, poor growth performance, hepatic pathology and higher blood lipid peroxidation were found in 60 and 100 g kg(-1) fish oil groups. Conversely, i…
Hemorheological benefits of omega-3 polyunsaturated fatty acids on erythrocyte deformability in renal transplanted patients
1994
The role of paraoxonase 1 (PON1) as an oxidation marker, in muscle improvement after increased beta-hydroxybutyrate (BHB) in blood, in patients with …
2020
Various studies have concluded that in multiple sclerosis (MS) metabolic changes related to energy alterations are generated at the mitochondrial level. These changes produce loss of muscle mass and lead to high levels of oxidative stress related to low levels of the enzyme Paraoxonase 1 (PON1). The ketone bodies, mainly beta-hydroxybutyrate (BHB), restore this energetic alteration by improving muscular activity. This pilot study was conducted over 4 months with 51 patients diagnosed with MS, randomly divided into: an intervention group that received an isocaloric diet of a Mediterranean origin supplemented with 60 ml of coconut oil; and a control group that received the same base diet but …
Identification of drying oils used in pictorial works of art by liquid chromatography of the 2-nitrophenylhydrazides derivatives of fatty acids.
2004
A new HPLC-UV-Vis method for identification of drying oils from binding media or protective film used in pictorial works of art prior to conservation or restoration is proposed. Chromophore derivatization of fatty acids released by hydrolysis of structural drying oils is studied. The derivatization reagent selected was 2-nitrophenylhydrazine with 1-ethyl-3-(3-dimethyl animopropyl)carbodiimide hydrochloride/pyridine as catalyst. This reaction was carried out using microwave heating. Mobile phase was methanol/water/n-propanol/acetic acid (80:14:5:1) running in isocratic mode. Absorbance was measured at 400nm. In these conditions, hydrazides of myristic, palmitic, oleic, and stearic acids were…
Methacrylate ester-based monolithic columns for nano-LC separation of tocopherols in vegetable oils
2010
The separation and determination of tocopherols (Ts) in vegetable oils by nano-LC chromatography with UV-vis detection using lauryl methacrylate ester-based monolithic columns has been developed. The separation of Ts was optimized in terms of mobile phase composition on the basis of the best compromise among efficiency, resolution and analysis time. Using a mobile phase composed of ACN/methanol/water, an excellent resolution between Ts was achieved within 18 min. The LODs were lower than 0.26 μg/mL, being repeatability values of retention time and peak area below 0.15 and 3.1%, respectively. The method was applied to the quantification of Ts and tocotrienols present in several vegetable oil…
Sterol stability in functional fruit beverages enriched with different plant sterol sources
2012
Abstract Two different plant sterol (PS) sources (free PS from tall oil and esterified PS from vegetable oils) were used for manufacturing two types of functional beverages (fruit and milk-based fruit beverages), and their PS and phytosterol oxidation product (POP) contents were determined. Gas chromatography–tandem mass spectrometry (GC–MS/MS) was used for identification and gas chromatography–flame ionization detection (GC–FID) for quantitation purposes. Brassicasterol, campesterol, campestanol, stigmasterol, β-sitosterol and sitostanol were the quantified PS, conforming a profile in order with current legislation. The relative percentages of PS differed according to the enrichment source…
Volatiles ofSideritis mugronensisFlower and Leaf
1991
ABSTRACT The composition of the essential oil obtained from the flowers and the leaves of Sideritis mugronensis in two different stages of their reproductive development is described. The major components of the leaf and flower oils were sabinene: 1.30–10.59% and 2.70–15.21%; 1,8-cineole: 11.60–17.19% and 11.06–28.65%; and α-bisabolol: 5.57–25.49% and 3.40–16.12% respectively.