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1.
Wild almond Amygdalus scoparia is a very fruitful tree that is spread over an extensive region of Iran. Considering its high quality oil, the development of clean extraction processes based on the use of compressed fluids is encouraged. In this study, the main factors involved in supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE) of wild almond have been optimized by using two different experimental designs and considering the oil extraction yield as a response variable; effects of time, temperature, pressure, and use of co‐solvents were studied for SFE while effects of time, temperature and type of solvent were evaluated for PLE. Results showed that the maximum oil yield using supercritical carbon dioxide was 42 %, obtained under the following conditions: extraction temperature, 40 °C; extraction pressure, 40 MPa; and 10 % ethanol as co‐solvent. The optimum extraction yield for PLE was 55 %, which was achieved using ethanol as solvent at 150 °C for 20 min. Lipidomic analysis revealed that the amount of oleic acid in the oil extracted by SFE was higher than those obtained by using other classical procedures. In addition, triacylglycerols constituted more than 98 % of the extracted oils.  相似文献   

2.
Large amounts of utilizable by-products are produced concomitant with silver carp processing. The lipids from fish brain contain considerable essential fatty acids which however have seldom been studied. In this study, the lipids extracted from the brain of silver carp exhibited good physicochemical properties. Forty volatile compounds were identified, of which hydrocarbons and aromatics predominated. The ratios of polar lipids and phospholipids to total lipids were 22.73 and 10.95 % respectively. Phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylserine (PS) accounted for 83.9 % of the phospholipids. Major fatty acids of neutral lipids, polar lipids, PC, PE and PS differed significantly. PE had the most polyunsaturated fatty acids (PUFA), while PC, PE and PS were rich in docosahexaenoic and eicosapentaenoic acids. Moreover, the ratios of fatty acids were considered to be reasonable due to high levels of n3 PUFA. The lipids from silver carp brain have been demonstrated to be healthy and nutritious. The results herein confirm that silver carp brain lipids are a commercially and industrially feasible prospect.  相似文献   

3.
Walnut (Juglans regia L.) oil (WO) from the varieties Chandler, Franquette, Hartley, Lara, Mayette, Serr, Sorrento and Tulare were studied in order to evaluate genotypical variations in fatty acid (FA) and volatile compositions, tocopherol content and oxidative parameters. Oil content was found to range between 71.4 and 73.9%. Oils obtained by pressing presented low acid (0.05–0.22% oleic acid), peroxide (0.05–0.47 meq O2/kg oil), K232, and K270 values, and moderate (247–365 µg/g oil) total tocopherol contents. Variations in unsaturated fatty acid contents were between 16.1 and 25.4% (oleic acid), 52.5 and 58.9% (linoleic acid), and 11.4 and 16.5% (linolenic acid). Oxidative stability (OS), as measured by the Rancimat method, was poor (2.64–3.44 h) and it correlated positively with oleic and negatively with linolenic acid contents. In contrast to their low OS, the antioxidant capacity evaluated through the 2,2‐diphenyl‐1‐picrylhydrazyl radical assay showed that the WO analyzed here have good radical‐scavenging activity. Tocopherols appear to be the most important contributors to this biochemical property. The findings connected with volatile composition showed a similar qualitative pattern where aldehydes were present at higher concentration. Most of them seem to come from unsaturated FA mainly through a chemical pathway.  相似文献   

4.
This study presented a refining process and reported on fatty acid composition and the physicochemical properties of the oil from black soldier fly larvae (BSFL). Crude larvae oil was purified through four steps consisting of degumming, neutralization, bleaching, and deodorization. Optimum degumming conditions that give the highest phospholipid weight and oil consisted of water concentration of 7% (v/v), followed by addition of H2SO4 at a concentration of 0.5% (v/v). Optimum conditions for saponification that maximize saponification value and free fatty acid (FFA) value were 0.4 mg NaOH/100 g oil, 1 hour, and 80 °C of NaOH quantity, reaction time, and temperature, respectively. The oil was then dehydrated using 10 mg Na2SO4/g oil. The bleaching process that gives maximum oil yield consisted of activated carbon at concentration of 5% (w/w), followed by centrifugation at a speed of 5000 rpm (radius = 86 mm) for 30 min. The contents of lauric acid, linoleic acid, and linolenic acid in purified oil were 28.8%, 11.1%, and 0.4%, respectively. Physicochemical properties of the refined oil included viscosity of 96 ± 0.14 cP (measured at 20 °C), FFA value of 0.45 ± 0.017%, acid value of 0.9 ± 0.043 mg KOH g−1, saponification value of 215.78 mg KOH g−1, iodine value of 53.7 gI2/100 g, and peroxide index of 133 mEq kg−1.  相似文献   

5.
The first step of bioadhesion on dental surfaces is the formation of the acquired pellicle. This mainly acellular layer is formed instantaneously on all solid surfaces exposed to oral fluids. It is composed of proteins, glycoproteins and lipids. However, information on the lipid composition is sparse. The aim of the present study was to evaluate the fatty acid (FA) profile of the in-situ pellicle for the first time. Furthermore, the impact of rinses with safflower oil on the pellicle’s FA composition was investigated. Pellicles were formed in situ on bovine enamel slabs mounted on individual upper jaw splints. The splints were carried by ten subjects over durations of 3–240 min. After comprehensive sample preparation, gas chromatography coupled with electron impact ionization mass spectrometry (GC–EI/MS) was used in order to characterize qualitatively and quantitatively a wide range of FA (C12–C24). The relative FA profiles of the pellicle samples gained from different subjects were remarkably similar, whereas the amount of FA showed significant interindividual variability. An increase in FA in the pellicle was observed over time. The application of rinses with safflower oil resulted in an accumulation of its specific FA in the pellicle. Pellicle formation is a highly selective process that does not correlate directly with salivary composition, as shown for FA.  相似文献   

6.
Free and esterified ergosterols are detected almost solely in fungi and are often employed as a biomarker of living fungi. In this work, the fatty acid composition and δ13C values of major fatty acids in triglycerides and ergosteryl esters from the fungus Ganoderma lucidum were analyzed by gas chromatography–mass spectrometer and gas chromatography–isotopic ratio mass spectrometer, respectively. The results showed that the fatty acid profiles varied in triglycerides and ergosteryl esters. The percentage of saturated fatty acids in ergosteryl esters was remarkably higher than that in triglycerides, where C18:1Δ9c was the predominant fatty acid and constituted 61.26 % of the total fatty acids. In contrast, C16:0 was the predominant fatty acid and constituted 71.88 % of the total fatty acids in ergosteryl esters. The study suggests that, after fungal death, free ergosterols in the cell membrane of the dead fungus were esterified with preferentially saturated fatty acids, mainly C16:0, from triglycerides and then stored in lipid particles for a longer period while free ergosterol markedly decreased. The δ13C values of C16:0, C18:0, C18:1 and C18:2 in ergosteryl esters exhibit a pronounced depletion in 13C compared with that in triglycerides within the range of ?1.3 to ?0.9 ‰, supporting the above inference. It is again suggested that free ergosterol in the cell membrane should be used as an indicator of living fungi, and ergosteryl esters in the lipid particles should not be included in the measurement of living fungal biomass.  相似文献   

7.
8.
Lipid oxidation can impact the odour of skin care products during storage. A study was conducted to identify and monitor representative markers for lipid oxidation in skin care products over time. Four lip care formulations and three skin care formulations with different lipid contents were stored at various cosmetic industry‐relevant conditions for 84 days. The skin care products were analysed for lipid hydroperoxides and secondary volatile oxidation products. A trained sensory panel performed an odour difference (triangle) test and odour‐profiled the products to detect and describe odour changes during storage. Several potential markers for lipid oxidation were identified. In skin care formulations, peroxide value (PV) analysis was a useful marker for lipid oxidation if the product was exposed to light during storage, but no clear changes were observed for PV in samples stored under other conditions. Furthermore, concentrations of several secondary volatile oxidation products increased during storage, and the highest increase was observed for products exposed to light. Pentanal and heptanal were found to be reliable markers for secondary volatile oxidation products in the skin care formulations (especially during exposure to light), whereas in the lip care formulations the best candidates were pentanal (especially during exposure to light and iron), 2‐methyl furan and 3‐methyl‐3‐buten‐2‐one (especially during exposure to light, iron and high temperatures).  相似文献   

9.
Curry leaves (Murraya koenigii. L. Spreng) dried using microwave, combo (combination of microwave and convection), infrared (IR), inert gas, hot air oven, cross-flow tray, freeze drying, and the effect of drying on flavor and quality characteristics such as chlorophyll analyzed by spectrophotometry and Ca, Fe, Mg, Cu, Na, K, and Zn by atomic absorption spectrophotometry (AAS) were compared with sun and shade drying along with fresh leaves. Clevenger hydrodistillation indicated that the shade-dried leaves (1.34%) retained a higher amount of essential oil followed by microwave-dried leaves (1.06%). About 65 components were identified by gas chromatography–mass spectroscopy (GC-MS) analysis and microwave drying retained a comparatively greater number of volatiles followed by combo-, IR-, and inert gas–dried samples. β-caryophyllene, E-β-ocimene, and italicene ether were found in all of the dried samples but in variable proportions.  相似文献   

10.
The photosulfochlorination process has been used in earlier works to produce n-alkane sulfonates. In this work, this process was applied for the first time on lauric and myristic fatty acids, leading to methyl ester sulfonates (MESs). The operating conditions were optimized and the isolation method described. Apart from the known advantages of this reaction, namely the use of sulfuryl chloride, the visible light and short reaction time, this process led to a clear mono-sulfonate products and thus allowed avoiding the bleaching step. The chemical composition of these surfactants was determined and their structures characterized by Fourier transform infrared spectroscopy, liquid chromatography-electrospray ionization tandem mass spectrometry and proton nuclear magnetic resonance. The physicochemical properties of these surfactants such as surface tension, critical micelle concentration, maximum surface excess and minimum area per molecule of surfactant at the air/water interface were determined. The Krafft point was determined experimentally and compared to the MES literature data. The experimental and calculated hydrophilic–lipophilic balance values obtained compared well. The foaming power using Bartsch’s method was presented and the results obtained compared to those of similar structures and those of sodium dodecyl sulfate.  相似文献   

11.
12.
The phenolic compounds of Italian and Turkish pistachio oil samples were investigated by gas chromatography–mass spectrometry (GC–MS) with the aim of identifying substances also present in very low concentration; 21 compounds were identified by means of the mass spectra of the trimethylsilyl (TMS) derivatives. Benzoic acid derivatives (protocatechuic acid, gallic acid, 4‐hydroxybenzoic acid) were the main components; 14 polyphenols were detected in pistachios for the first time. The concentrations of the compounds found were in the range 0.02–5.64 μg/g of fresh pistachio. No appreciable qualitative differences were found between samples of different origin; a multivariate approach was successfully tried to differentiate the samples according to their geographical origin, using Principal Component Analysis (PCA). Finally, Canonical Discriminant Analysis (CDA) was further conducted to classify different pistachio samples.  相似文献   

13.
14.
The study was designed to characterise two extracts of Western Australian sandalwood (Santalum spicatum) seed oils for their physicochemical and lipid characteristics. Sandalwood plantation’s surplus seeds could be used for their oil content, to improve the commercial viability of this industry. The seed oils were obtained by solvent extraction and supercritical carbon dioxide extraction respectively. Important physicochemical parameters were compared with other oils commonly used in pharmaceutical and cosmetic products. Acid values were found to be higher (6.0–7.5 mg KOH/1 g oil) while peroxide values (6.7–9.0 mequiv/Kg) were lower than reported for other oils. Tocopherols were found to be lower than those usually reported for nut oils (α-tocopherol 1–3 mg/100 g; δ-tocopherol 2.2–5.7 mg/100 g), squalenes and phytosterols were found in considerable quantities. The fatty acid content consisted largely of ximenynic acid (35 %) and oleic acid (52 %). No oxidative derivatives of fatty acids were observed. Although there were statistically significant differences in some properties, the magnitude of these were insufficient to conclude there were any notable differences in the two oil extracts.  相似文献   

15.
Moringa ovalifolia tree is indigenous to Namibia and is a multipurpose tree whose leaves, pods, fruits, and flowers are edible. The tree is well adapted to the harsh climatic conditions of the region and easily cultivated. In this paper, we investigate the physicochemical characteristics of the oil extracted from M. ovalifolia seeds collected from Remhoogte Farm, Khomas region, Namibia. The oil yield was 34.86 ± 2.47%. The oil contained a high level of monounsaturated fatty acids, with oleic acid (18:1) being the dominant one. The oil had high levels of tocopherol, with a total of 44.56 mg 100 g?1 of oil, comprising α‐tocopherol (33.94 mg 100 g?1), β‐tocopherol (6.64 mg 100 g?1), and δ‐tocopherol (3.98 mg 100 g?1). High levels of stigmasterol (142.41 mg 100 g?1) and β‐sitosterol (330.70 mg 100 g?1) were also detected. The seed oil exhibited good‐quality characteristics, making it a useful new seed oil to be considered for food and nonfood applications.  相似文献   

16.
The lipid content and fatty acid (FA) composition of seeds from the Asian ginseng Panax ginseng growing naturally in taiga forests of the Russian Far East and seeds from cultivated ginseng were studied in this work. The total lipid content of seeds from both wild and cultivated plants was 9–12 % of fresh weight. FA were analyzed as isopropyl esters on a polar capillary column BD‐225, which allows good separation of petroselinic and oleic acids. The structure of FAs was confirmed using GC–MS of fatty acid methyl ester (FAME) and 4,4‐dimethyloxazoline derivatives. In all the seed samples, the major FA was petroselinic acid 18:1(n‐12) which comprised more than 60 %; the contents of oleic and linoleic acids were lower (15–17 and 15–16 %, respectively). Earlier, a higher level (>80 %) of oleic acid had been reported for ginseng seeds. This discrepancy can be explained by an insufficient separation of these acids on standard columns used for GC of FAME. In general, seeds of wild and cultivated ginseng are very similar in lipid content and FA composition.  相似文献   

17.
Moringa oleifera is grown all over the world as a crop for its nutritious pods, leaves and seeds. The purpose of the present study was to evaluate the oil percentage, density, iodine value, saponification value, acid value and fatty acid profile of Egyptian moringa Seed oils. Moringa seeds were irradiated using 60Co at dose levels of 0.0 (control), 5, 10 and 15 kGy and oil was extracted from unirradiated and irradiated samples. Results showed that the oil percentage and density were almost unaffected. Irradiation reduced the iodine value, whereas the acid and saponification values were increased in all irradiated samples. The oil was found to contain high levels of unsaturated fatty acids, especially an omega‐9‐fatty acid (oleic) (up to 76.29 %) at a dose level of 15 kGy. Also at the same dose level, the dominant saturated acids were palmitic, stearic acid and arachidic (the three up to 12.66 %). GC–MS revealed the presence of different compounds (more than 50) in the moringa oil extract, among them alkaloids, terpenoids steroids, saturated and unsaturated fatty acids, aromatic and aliphatic hydrocarbons and polyphenolic compounds. Phenolic and falvonoid were significantly increased by increasing irradiation dose levels. Also, the antioxidant activity of irradiated seed oil increased by increasing the phenolic and flavonoid contents. Moringa oleifera could be grown by wide scale production as a potentially valuable crop. However, isolation of individual compounds and their biological activities needs to be covered in future to enhance its pharmacological importance and to open new avenues of research.  相似文献   

18.
The influence of a plasticizer in the form of the residual solvent dimethylacetamide on pervaporation and sorption properties of membranes based on poly(phenylene isophtalamide) (PA) was investigated. To analyze the influence of the plasticizer on membrane transport properties, pervaporation of binary water–ethyl acetate mixtures was studied. The method of sorption calorimetry was used to investigate water sorption properties of the studied membranes and PA powder. Moreover, to characterize the PA membranes, contact angle measurements and thermogravimetric analysis (TGA) were applied. It is shown that the presence of a residual organic solvent significantly changes the sorption and transport characteristics of the membranes. The residual organic solvent increases the amount of water absorbed by the polymer membrane. In pervaporation of water/ethyl acetate mixtures, the presence of the residual solvent dimethylacetamide makes the membrane more permeable but less selective for water separation.  相似文献   

19.
20.
The volatile fraction of three vegetable oils recommended for deep‐frying due to their high MUFA:PUFA ratios, namely extra‐virgin olive oil, peanut oil and canola oil, was compared before and after frying potatoes, with a particular focus on toxic volatiles. For the purpose, a headspace solid‐phase‐micro extraction technique coupled with gas chromatography and mass spectrometry was optimized, with semi‐quantification achieved using two internal standards. Significant qualitative and quantitative differences were observed, both before and after frying. From a total of 51 compounds, aldehydes were the main group formed after deep‐frying, their nature and abundance being highly associated with the initial fatty acid composition, particularly linoleic acid (r2 = ?0.999, p ≤ 0.001). Globally, extra‐virgin olive oil revealed fewer formations of unsaturated aldehydes, including toxic ones, and correlated with lower amounts of degradation indicators, as polar compounds (r2 = 0.998, p ≤ 0.001) and p‐anisidine value (r2 = 0.991, p ≤ 0.001). Despite the similarities in total unsaturation degree between canola and peanut oils, the former presented lower amount of volatiles, including E,E‐2,4‐decadienal and acrolein, the more toxic ones. These results highlight for the pertinence of volatile analyses to evaluate and compare oil degradation under thermal and oxidative stress, while complementing other degradation indicators. Additionally, the optimized methodology allows a direct comparison of different oil matrices, supporting further developments into more general methods for volatiles quantification, enabling more efficient comparison of results between research teams.  相似文献   

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