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1.
Vegetable oils have kairomonal attractant properties to grasshoppers primarily due to the presence of linoleic and linolenic fatty acids. These fatty acids are dietary essentials for grasshoppers and, once volatilized, can be detected by the insects’ olfactory receptors. A laboratory bioassay method has been developed to identify vegetable oils that have fatty acid profiles similar to grasshoppers and that induce grasshopper attraction and feeding. Such oils could be useful kairomonal adjuvants and/or carriers for acridicide formulations. Three sets of laboratory bioassays demonstrated that the addition of a standard aliquot of different vegetable oils resulted in varying degrees of grasshopper feeding on otherwise neutral substrates. Addition of olive oil stimulated the greatest feeding in all three sets of assays, regardless of the age of the tested insects. Furthermore, addition of canola or flax oils markedly enhanced grasshopper feeding. These three oils—i.e., olive, canola, and flax oil—proved to be the best performing grasshopper stimulants. A second group of oils included rapeseed-flax mix and rapeseed oils; however, their performance was not as consistent as oils in the first group—especially with regard to nymphal feeding. A third group of oils consisted of soybean, corn, peanut, and sunflower oil. Theoretical expectations regarding these oils varied wildly, suggesting that the results of a single bioassay should be cautiously interpreted as being negative.  相似文献   

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We introduce a visible Raman spectroscopic method for determining the free fatty acid (FFA) content of extra virgin olive oil with the aid of multivariate analysis. Oleic acid was used to increase the FFA content in extra virgin olive oil up to 0.80% in order to extend the calibration span. For calibration purposes, titration was carried out to determine the concentration of FFA for the investigated oil samples. As calibration model for the FFA content (FFA%), a partial least squares (PLS) regression was applied. The accuracy of the Raman calibration model was estimated using the root mean square error (RMSE) of calibration and validation and the correlation coefficient (R 2) between actual and predicted values. The calibration curve of actual FFA% obtained by titration versus predicted values based on Raman spectra was established for different spectral regions. The spectral window (945–1600 cm−1), which includes carotenoid bands, was found to be a useful fingerprint region being statistically significant for the prediction of the FFA%. High R 2 and small RMSE values for calibration and validation could be obtained, respectively.  相似文献   

4.
The objective of this study was to determine the fate of phytosterols in vegetable oils with varying fatty acid composition used for frying. High oleic sunflower (HOSun), corn (Corn), hydrogenated soybean (HSBO), expeller pressed soybean (ESBO), and expeller pressed low-linolenic acid soybean oil (ELLSBO) were used for frying potato chips in a pilot plant-scale continuous fryer. The same oils, and regular soybean oil (SBO) were also used in intermittent batch frying of tortilla chips. Phytosterols were measured in oils collected at various times during frying by GC to determine their loss. The formation of polymerized triacylglycerides (PTAGs) and total polar compounds (TPC) were analyzed to determine the extent of oil degradation. In the continuous frying system, phytosterol loss ranged between 4 and 6% in ESBO, ELLSBO, HOSun, and Corn, with no loss in HSBO. PTAGs and TPC were highest in ESBO and ELLSBO, followed by Corn, HOSun, and HSBO. In the batch frying experiment, phytosterol loss ranged from 1 to 15%, and was highest in Corn followed by SBO and HSBO. There was no significant loss of phytosterols in ESBO, ELLSBO, and HOSun. Formation of PTAGs and TPC during batch frying was highest in SBO and ESBO, followed by Corn, ELLSBO, HOSun, and HSBO. In conclusion, phytosterol loss in both the continuous fryer and in the batch frying system appeared to be unrelated either to fatty acid composition, or to the extent of oil degradation. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the US Department of Agriculture.  相似文献   

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The current work has shown the potentials for the aerobic oxidation of fatty acid methyl ester (FAME) of vegetable oils in the production of polyvinylchloride (PVC) plasticizers with the exclusion of other reagents. The reaction mixtures contain epoxidized derivatives of FAME, and esters, with the quantity of the ester groups being higher than in the initial raw material. It was established that the increase in the additional ester groups resulting from the “aerobic” Baeyer-Villiger (BV) reaction has a significantly positive influence on the plasticizing ability of the oxidized FAME mixtures for PVC when compared to the formation of epoxide compounds. The development of the technology for the production of PVC plasticizers proposed in this investigation provides an opportunity for resolving some of the environmental issues normally associated with the use of phthalate-based plasticizers.  相似文献   

7.
The ozonolysis of unsaturated lipids is a process that has been used to generate aldehydes, acids, alcohols, and other biobased chemical intermediates. Reported here is a method that can be used to measure the formation of nonanal and oleic acid during the ozonolysis of unsaturated vegetable oil fatty acids or their methyl esters to indicate the extent of the ozonolysis reaction. Derivatization was performed using boron trifluoride in methanol solution to transform nonanal and oleic acid into nonanal dimethyl acetal and oleic acid methyl ester, respectively. Undecanal and 10‐heptadecenoic acid were used as internal standards and separation was performed using gas chromatography coupled with a flame ionization detector. The method was validated by performing a standard addition procedure in which nonanal or oleic acid standards were spiked into samples collected during the ozonolysis of oleic acid or canola oil fatty acid methyl ester (FAME). Linear regression results indicated that the measured nonanal and oleic acid are in good agreement with the actual amounts of nonanal and oleic acid added to the sample with at least 98 % recovery. The application of the method was demonstrated by the successful measurement of nonanal and oleic acid formed throughout the ozonolysis process for high oleic canola oil FAME.  相似文献   

8.
Characterizations of fatty acids composition in % of total methylester of fatty acids (FAMEs) of fourteen vegetable oils—safflower, grape, silybum marianum, hemp, sunflower, wheat germ, pumpkin seed, sesame, rice bran, almond, rapeseed, peanut, olive, and coconut oil—were obtained by using gas chromatography (GC). Saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA), palmitic acid (C16:0; 4.6%–20.0%), oleic acid (C18:1; 6.2%–71.1%) and linoleic acid (C18:2; 1.6%–79%), respectively, were found predominant. The nutritional aspect of analyzed oils was evaluated by determination of the energy contribution of SFAs (19.4%–695.7% ERDI), PUFAs (10.6%–786.8% ERDI), n-3 FAs (4.4%–117.1% ERDI) and n-6 FAs (1.8%–959.2% ERDI), expressed in % ERDI of 1 g oil to energy recommended dietary intakes (ERDI) for total fat (ERDI—37.7 kJ/g). The significant relationship between the reported data of total fat, SFAs, MUFAs and PUFAs intakes (% ERDI) for adults and mortality caused by coronary heart diseases (CHD) and cardiovascular diseases (CVD) in twelve countries has not been confirmed by Spearman’s correlations.  相似文献   

9.
Globoid cell leukodystrophy or Krabbe disease is an inherited autosomal recessive disorder caused by mutations in the galactosylceramidase gene. The objective of the study was to present information about the fatty acid (FA) composition of the brain and serum of twitcher mice, a mouse model of Krabbe disease, compared to wild type, in order to identify biomarker of disease progression. We defined the FA profiles by identifying the main components present in serum and brain using GC‐EI‐MS analysis. The FA percentage composition was measured and data were analyzed considering the disease and the mouse age as experimental factors. Significant correlations were established, both in brain and in serum, in the fatty acid percentage composition of twitcher compared to wild type mice. The most abundant saturated fatty acid in brain was the palmitic acid (C16:0) with mean values significantly increased in twitcher mouse (p = 0.0142); moreover, three monounsaturated, three polyunsaturated (PUFA) and a plasmalogen were significantly correlated to disease. In the serum highly significant differences were observed between the two groups for three polyunsaturated fatty acids. In fact, the docosahexaenoic acid (C22:6n3c) content was significantly increased (p = 0.0116), while the C20 PUFA (C20:3n6c and C20:5n3c) were significantly decreased in twitcher serum samples. Our study shows a specific FA profile that may help to define a possible pattern that could distinguish between twitcher and wild type; these data are likely to provide insight in the identification of new biomarkers to monitor the disease progression and thereby permit the critical analysis of therapeutic approaches.  相似文献   

10.
To develop the potential applications of Plantago plants, seed oils were extracted from 14 cultivars of Plantago around China. Their fatty acid profiles, tocopherols, carotenoid compositions, anti‐inflammatory and antioxidant properties were also investigated. The Plantago seed oils (PSO) were abundant in linolenic acid from 11.12 to 29.36 g/100 g oil and had low fatty acid ratio of n‐6/n‐3 ratio matched with the dietary recommendations. The tocopherol contents of PSO ranged from 693.25 to 3708.80 μg/g and the lutein contents ranged from 2.29 to 26.68 μg/g. The PSO showed significant inhibitory effects on TNF‐α, IL‐1β, and COX‐2 mRNA expression in RAW 264.7 mouse macrophage cells induced by LPS. In addition, the properties on scavenging DPPH, oxygen and hydroxyl radicals indicated that PSO had potential antioxidant properties. The results could develop PSO as novel functional foods to improve human health.  相似文献   

11.
Hydrogenation of sunflower and canola oils over a novel Pd-supported catalyst (pore size of 6.8 nm and BET specific surface area of 837 m2/g) was investigated and compared to commercial nickel catalyst. The formulated catalyst with Pd-loading of 1 wt%, supported on structured silica material was active and selective for the hydrogenation of sunflower and canola oils under mild process conditions. For both oils, the novel Pd supported catalyst exhibited a better selectivity than commercial Ni catalyst at a similar activity with a lower metal loading. For the same iodine value (IV) reduction, the Pd-catalyst produced less saturated fatty acids (SFA) and about the same level of trans fatty acids (TFA), but was more selective towards cis monoenes formation than Ni-catalyst. More importantly, this catalyst produced a reduced level of stearic acid, which at increased levels causes waxy mouth feel of the hydrogenated fat.  相似文献   

12.
Sesame mutants with closed capsules, determinate growth habit and wilt resistance, have been proposed to be suitable for intensive management conditions facilitating mechanized harvesting. The objective of our experiment was to determine the oil content and fatty acid composition of these mutants before they are placed on the market. Oil content and fatty acids were studied in 19 mutants, 6 breeding lines and 4 control source genotypes. The oil contents of the seeds ranged from 46.4 to 62.7%. The mutants had generally a lower oil content than the control genotypes except the wilting tolerant group. For unsaturated fatty acids, oleic acid was higher in the mutants and breeding lines while linoleic acid was lower in the seed oil. However, no mutants or breeding lines were found with radically different composition or with any undesirable lipid component. The closed capsule and determinate growth habit mutants need to be improved for oil content while their fatty acid composition is fine.  相似文献   

13.
The search for alternative fuels has been gaining attention in recent decades. The replacement of fossil fuels is driven by environmental, economic, and social factors, since the whole of society is dependent on their usage; and in this context, one alternative that has been highlighted is the use of biodiesel. Biodiesel represents a renewable, biodegradable, non‐inflammable, and low toxicity alternative to diesel. In this study, the Hansen solubility parameters (HSPs) and the interaction radii (R0) were determined for the following materials: used frying oil, coconut oil, palm oil, biodiesel from used frying oil, diesel, and biodiesel–diesel blends (B10 and B20), using 45 solvents and solvent mixtures. The values found for the solubility parameters of the used frying oil and coconut oil were very close to those found for the biodiesel; however, the biofuel showed higher solubility in polar solvents. The values of solubility parameters of diesel, B10, and B20 were similar, increasing values according to the amount (by volume) of biodiesel added to diesel fuel.  相似文献   

14.
Triglycerides and vegetable oils are amongst the most difficult oils to remove from fabrics due to their highly hydrophobic nature; this is all the more challenging as cold water detergency is pursued in the interest of energy efficiency. Recently, extended surfactants have produced very encouraging detergency performance at ambient temperature, especially at low surfactant concentration. However, the salinity requirement for extended surfactants was excessive (4–14%) and there is limited research on extended‐surfactant‐based microemulsions for cold water detergency (below 25 °C). Therefore, extended‐surfactant‐based microemulsions are introduced in this study for cold temperature detergency of vegetable oils with promising salinity and surfactant concentration. The overall goal of this study is to explore the optimized microemulsion formulations with low surfactant and salt concentration using extended surfactant for canola oil detergency at both 25 and 10 °C. It was found that microemulsion systems achieved good performances (higher than those of commercial detergents) corresponding to IFT value 0.1–1 mN/m with the surfactant concentration as low as 10 ppm and 4% NaCl at 25 °C, and as low as 250 ppm and 0.1% (1000 ppm) NaCl at 10 °C. In addition, microemulsion systems were investigated with a different salt (CaCl2, or water hardness, versus NaCl) at 10 °C, demonstrating that 0.025% CaCl2 (250 ppm) can produce good detergency; this is in the hardness range of natural water. These results provide qualitative guidance for microemulsion formulations of vegetable oil detergency and for future design of energy‐efficient microemulsion systems.  相似文献   

15.
Chlorella zofingiensis has great potential for astaxanthin and fatty acid production. This study investigated the accumulation of astaxanthin and total fatty acids (TFA), the fatty acid compositions of astaxanthin esters and TFA in photoautotrophic and heterotrophic C. zofingiensis, respectively. The results displayed that in photoautotrophic cells, 18:3 was the most predominant fatty acid, followed by 16:0, 18:2, and 18:1, while astaxanthin mono-esters (mono-AE) contained only 16:0 and 18:0, and astaxanthin di-esters (di-AE) contained 16:0 mostly, followed by 18:1, 18:0, 18:2, and 18:3. C. zofingiensis accumulated the highest level of astaxanthin and TFA under heterotrophic conditions fed with 30 g L−1 glucose. The percentage of 18:1 in TFA, mono-AE, and di-AE increased from 10.05%, 0%, and 17.76% to 35.80%, 14.84%, and 50.12%, respectively; in contrast, the percentages of 18:3 in TFA and di-AE were observed to decrease from 40.42% and 7.59% to 9.56% and 1.30%, respectively, in comparison with those in photoautotrophic ones. The RNA sequencing (RNA-seq) results showed that the expressions of the genes in astaxanthin and fatty acid biosynthetic pathways were increased under this heterotrophic condition. These results indicated differential accumulation of AE and TFA, especially fatty acid compositions of TFA and AE in photoautotrophic and heterotrophic cells, suggesting a positive correlation between astaxanthin and fatty acid biosynthesis.  相似文献   

16.
Mixtures of fatty acids and rosin acids are industrially important products utilized as a raw material for several purposes. Their thermal properties, especially cold stability and crystallization behavior is also important. Several fatty acid and rosin acid mixtures both from industrial products and from commercially available fatty and rosin acids were prepared and treated for 30 min at 80 °C under an inert atmosphere. Thereafter, the mixture was cooled to the desired temperature. Determination of the cloud point, chemical analysis of liquid and solid phase, thermal analysis by differential scanning calorimetry as well as morphology analysis by scanning electron microscopy were performed. The results revealed that crystallization was more rapid when it occurred at 10 °C compared to 25 °C. The crystal sizes increased with decreasing the crystallization temperature. Furthermore, crystals were of irregular shape and agglomerated when rapid cooling of the mixture occurred. Chemical analysis revealed that liquid phase was enriched with stearic acid, whereas crystals contained large amounts of abietic, dehydroabietic and linoleic acids. The cloud point of the mixtures increased with increasing amount of stearic and rosin acids. Dehydroabietic acid addition improved the cold stability of the synthetic fatty acid–rosin acids mixture.  相似文献   

17.
Lipid metabolism, inflammation, oxidative stress and endothelial function play important roles in the pathogenesis of cardiovascular disease (CVD), which may be affected by an imbalance in the n‐6/n‐3 polyunsaturated fatty acid (PUFA) ratio. This study aimed to investigate the effects of the n‐6/n‐3 PUFA ratio on these cardiovascular risk factors in rats fed a high‐fat diet using plant oils as the main n‐3 PUFA source. The 1:1 and 5:1 ratio groups had significantly decreased serum levels of total cholesterol, low‐density lipoprotein cholesterol, and proinflammatory cytokines compared with the 20:1 group (p < 0.05). Additionally, the 20:1 group had significantly increased serum levels of E‐Selectin, von Willebrand factor (vWF), and numerous markers of oxidative stress compared with the other groups (p < 0.05). The 1:1 group had a significantly decreased lipid peroxide level compared with the other groups (p < 0.05). Serum levels of malondialdehyde, reactive oxygen species and vWF tended to increase with n‐6/n‐3 PUFA ratios increasing from 5:1 to 20:1. We demonstrated that low n‐6/n‐3 PUFA ratio (1:1 and 5:1) had a beneficial effect on cardiovascular risk factors by enhancing favorable lipid profiles, having anti‐inflammatory and anti‐oxidative stress effects, and improving endothelial function. A high n‐6/n‐3 PUFA ratio (20:1) had adverse effects. Our results indicated that low n‐6/n‐3 PUFA ratios exerted beneficial cardiovascular effects, suggesting that plant oils could be used as a source of n‐3 fatty acids to prevent CVD. They also suggested that we should be aware of possible adverse effects from excessive n‐3 PUFA.  相似文献   

18.
Keeping in view the present day demand for foods with healthy fats, the effect of different fats namely hydrogenated fat (HF) and bakery fat (BF); oils—sunflower oil (SFO), soyabean oil (SBO), olive oil (OLO), palm oil (POO) and coconut oil (CNO) separately at the level of 7.5 % on the rheological, fatty acid profile and quality characteristics of parotta was studied. Addition of fats and oils decreased Farinograph water absorption, Amylograph peak viscosity, Alveograph resistance of dough to deformation and increased average abscissa at rupture. In the micrographs of parotta dough with fats, the protein matrix appeared thick and intact, whereas in the case of parotta dough with oils the protein matrix appeared slightly less intact. The spread ratio and overall quality of parotta with oils were higher than fats. The highest overall quality score was observed for parotta with OLO, followed in decreasing order by SFO, SBO, CNO, POO, HF and BF. Determination of fatty acid profile showed that the parottas with fats contained a high amount of trans fatty acids (TFA), while parottas with oils had no TFA. During storage up to 48 h, the parottas with oils remained softer than the parottas with fats.  相似文献   

19.
Seed oils sourced from West Africa are generally not well-characterized, but likely to have an untapped potential. This review aims to make an overview of fatty acid (FA) composition of unconventional seed oils from semi-arid West African trees and evaluate potential for new and enhanced uses and for improving local livelihoods and biodiversity conservation. A total of 111 studies on FA composition were found, covering 31 species. Only 69 of the studies (62%) were included in the review, as 38% had unreliable or incomplete results. There was a clear link between taxonomic kinship and FA composition. Over 20 potentially interesting and underexploited oils were found, including oils with properties similar to palm oil, olive oil, coconut oil, shea butter, and cotton seed oil. About half of the oils have promising potential for cosmetics. One third of the oils were relatively saturated, indicating properties for structuring food and heat resistance. Most of the species had multiple uses and oil production could be profitable in co-production with other non-timber forest products. Furthermore, establishment of sustainable oil production and domestication of oil trees could promote biodiversity conservation. Enhanced oil production in semi-arid West Africa is promising, but several practical constraints remain to be overcome.  相似文献   

20.
There is limited variability within rapeseed germplasm in Morocco. Induced mutation was recently used to generate novel genetic variability and develop mutant lines combining desirable traits. In this context, nine promising advanced rapeseed M2 mutant lines and the wild-type variety “INRA-CZH2” were evaluated for their seed oil content, fatty acid composition, total phenolic content (TPC), and free-radical scavenging activity (FRSA) by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) methods. The results showed significant variability among all mutants in seed oil content (38.14–42.04%) and fatty acids (SAFA = 5.49–10.99%, MUFA = 50.33–71.62%, PUFA = 22.89–8.68%). The mutant H2M-5 exhibited the highest fraction of MUFA and the lowest proportion of SAFA and PUFA, while the mutant H2M-4 showed the highest SAFA and PUFA amounts and the lowest MUFA level. TPC varied from 2.16 to 4.35 mg GAE/100 g. The highest amount was found in the mutant H2M-1, which is about twice that of other mutants and the wild-type variety. FRSA differed significantly among the samples, and the variations observed for DPPH and ABTS methods were 40.5–59.28% and 40.31–59.86%, respectively. FRSA was positively correlated to TPC in the sampled oils (r = 0.801 and 0.802, P < 0.01). This is the first report emphasizing the biochemical potential of rapeseed varieties and novel mutants in Morocco. H2M-1, H2M-4, and H2M-5 were proposed for the Rapeseed National Breeding Program, as they showed higher levels in some biochemical traits of interest.  相似文献   

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