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1.
The fatty acid and triacylglycerol composition of a vegetable oil determine its physical, chemical and nutritional properties. The applications of a specific oil depend mainly on its fatty acid composition and the way in which fatty acids are arranged in the glycerol backbone. Minor components, e. g. tocopherols, also modify oil properties such as thermo‐oxidative resistance. Sunflower seed commodity oils predominantly contain linoleic and oleic fatty acids with lower content of palmitic and stearic acids. High‐oleic sunflower oil, which can be considered as a commodity oil, has oleic acid up to around 90%. Additionally, new sunflower varieties with different fatty acids and tocopherols compositions have been selected. Due to these modifications sunflower oils possess new properties and are better adapted for direct home consumption, for the food industry, and for non‐food applications such as biolubricants and biodiesel production.  相似文献   

2.
The ability of soil and water conservation crops to resist stress is closely related to their abundance of lipid-soluble chemical components. This study systematically evaluated the composition and content of fatty acids, sterols, squalene, and tocopherol in oils extracted from three varieties of crops growing on the Chinese Loess Plateau with extreme environments. The dominant fatty acids in the wild seabuckthorn pulp oil were oleic acid (29.73%), palmitic acid (26.83%), and palmitoleic acid (25.71%), and those in wild seabuckthorn seed oil were linoleic acid (42.29%), α-linolenic acid (20.65%), and oleic acid (18.94%). The most abundant fatty acids in wild elaeagnusmollis seed oil were oleic acid (43.29%), linoleic acid (35.93%), and α-linolenic acid (7.00%). Wild yellowhorn seed oil was rich in linoleic acid (34.14%), oleic acid (25.99%), and erucic acid (8.76%). Seabuckthorn seed oil had the highest levels of total sterols (619.33 mg/100 g), followed by seabuckthorn pulp oil (606.10 mg/100 g), yellowhorn seed oil (249.46 mg/100 g), and elaeagnusmollis seed oil (224.01 mg/100 g). However, the squalene content was highest in elaeagnusmollis seed oil (68.06 mg/100 g) and similarly low in yellowhorn seed oil (9.81 mg/100 g), seabuckthorn pulp oil (4.62 mg/100 g) and seabuckthorn seed oil (4.71 mg/100 g). In addition, seabuckthorn pulp oil had the highest tocopherol content (179.92 mg/100 g), followed by seabuckthorn seed oil (130.57 mg/100 g), elaeagnusmollis seed oil (85.87 mg/100 g), and yellowhorn seed oil (45.44 mg/100 g). This study provides favorable data supporting biomass resource utilization and organic synthesis of bioactive raw chemical composition.  相似文献   

3.
As important oil crops in Inner Mongolia, sunflower, and flaxseed had distinct lipid profiles in seeds. As an emerging cash crop, Hibiscus manihot L. has strong potential market competitiveness. In this study, the lipidome, fatty acid composition and quality characteristics of flaxseed, H. manihot L., and sunflower seed oils were analyzed and compared. A total of 270 distinct lipids were identified and analyzed with an emerging detection approach—lipidomics, which illustrated the tremendous difference among the samples. triacylglycerol, diacylglycerol and polar lipids were the most abundant lipids in all samples. H. manihot L. seeds contained higher saturated and monounsaturated fatty acids and lower polyunsaturated fatty acids. H. manihot L. seed oil had the longest oxidative stability index time, high content of vitamin E and total phenolics, while flaxseed oil embodied the lowest oxidative stability. The peroxide value and acid value of the three oils were within the allowable range of Chinese national standards.  相似文献   

4.
Analyses of the seed oil of 43Linum species showed great variability in fatty acid composition. The species can be grouped in two broad categories on the basis of seed oil composition: 1) Those with high linolenic, low linoleic and low oleic acid content, and 2) Those with high linoleic, low linolenic and low oleic acid content. A positive correlation was observed between iodine value and linolenic acid content, and a negative correlation between linolenic and linoleic acid content. There was no correlation between fatty acid composition and chronosome number. No. 1722, University of California Citrus Research Center and Agriculture Experiment Station, Riverside, California.  相似文献   

5.
Seed oil content of globe artichoke and its composition were assessed under three irrigation regimes, including irrigation at 20, 50, and 80 % depletion of soil available water. Water deficit affected the phenological characteristics, amount and the quality of the oil as well as the phenolics and antioxidant activity of the leaves and capitula. The seed oil content ranged from 18.7 % in 80 % to 22.8 % in 20 % treatment. The fatty acid composition of oil was determined using gas chromatography (GC). The predominant fatty acids in the oil were linoleic (51.68 %), oleic (34.22 %), palmitic (9.94 %), and stearic (3.58 %). Water deficit leads to reduced oil content, linoleic acid, the unsaturated/saturated fatty acid ratio and the iodine value. On the other hand, some other fatty acids such as palmitic and oleic acid and also the ratio of oleic/linoleic acid were elevated due to water deficit. Higher antioxidant activity was observed in capitula (IC50 = 222.6 μg ml?1) in comparison to the leaves (IC50 = 285.8 μg ml?1). Finally, the severe drought stress condition caused to gain higher oil stability, while the highest seed oil content and unsaturated fatty acids in the oil was obtained in non‐stress condition. Moreover, high phenolics, flavonoids and antioxidant activity as well as appreciable dry matter content were obtained in the moderate water stress condition.  相似文献   

6.
Echium plantagineum seed contains a highly polyunsaturated oil (approximately 14% linoleic acid, 10% γ‐linolenic acid, 33% α‐linolenic acid and 14% stearidonic acid); almost half of the fatty acids are omega‐3 fatty acids, so there is an interest in the possible health benefits of this oil, which, once extracted, is prone to oxidation. For the first time in reported literature, oil bodies (OBs), the organelles that store the oil in mature seed, were recovered from E. plantagineum seeds. The oxidative stability of these organelles ex vivo, dispersed in an aqueous continuous phase, was tested against processed E. plantagineum oil emulsions stabilised with either SDS or Tween 20. For both primary and secondary oxidation products the OBs were the most stable form of dispersed oil, and the dispersed systems were all more stable than bulk E. plantagineum oil after incubating at 40°C for 7 days. The possible reasons for the enhanced chemical stability of E. plantagineum OBs are explored in this paper. Practical applications: OBs, the natural store of oil in oilseeds, can be recovered from seeds intact and are relatively stable to oxidation ex vivo. Echium seed OBs, enriched in physiologically active omega‐3 fatty acids, therefore offer an attractive alternative to traditional oil extraction methods and overcome the need to encapsulate the omega‐3 rich oil.  相似文献   

7.
Leaves from soybean (Glycine max (L.) Merr.) plants were assayed to determine if the relationship between temperature and relative fatty acid composition observed in the seed oil also existed for the triglycerides in the leaf oil. Leaf samples were harvested from eight soybean lines (A5, A6, C1640, Century, Maple Arrow, N78-2245, PI 123440 and PI 361088B) grown at 40/30,28/22 and 15/ 12°C day/night. At 40/30 and 28/22°C, seven fatty acids were observed at a level greater than 1.0%. These included the five major fatty acids found in the seed oil: palmitic (16:0), stearic (18:0), oleic (18:1), linoleic (18:2) and linolenic (18:3) acid; plus two fatty acids that had retention times the same as palmitoleic (16:1) and γ-linolenic (18:3 g) acid. In addition, an eighth fatty acid that had a retention time the same as behenic (22:0) acid was found in the leaves of all lines at 15/12°C. Palmitic, palmitoleic and stearic acid content did not differ significantly over temperatures. The oleic and linoleic acid content were each highest at 15/12°C, while the γ-linolenic and the linolenic acid content were each highest at 40/30°C. The fatty acid composition of the triglyceride portion of the leaf oil did not display the same pattern over temperatures as that observed for seed oil.  相似文献   

8.
Ten soybean genotypes grown in 1992 with seed size ranging from 7.6 to 30.3 g/100 seeds and maturity group V or VI were selected and tested for oil and protein content and for fatty acid composition. In these germplasm, protein varied from 39.5 to 50.2%, oil, 16.3 to 21.6%, and protein plus oil, 59.7 to 67.5%. Percentages of individual fatty acids relative to total fatty acids varied as follows: palmitic, 11.0 to 12.8; stearic, 3.2 to 4.7; oleic, 17.6 to 24.2; linoleic, 51.1 to 56.3 and linolenic, 6.9 to 10.0. Seed size showed no significant correlations with individual saturated fatty acids, protein or oil content. However, significant correlations were found between seed size and individual unsaturated fatty acids: positive with oleic, and negative with linoleic and linolenic. Oil and protein content were negatively correlated with each other. Among the major fatty acids, only the unsaturated were significantly correlated with each other: negative between oleic and linoleic or linolenic, and positive between linoleic and linolenic. A subsequent study with soybeans grown in 1993 generally confirmed these findings. Variation in relative percentages of unsaturated fatty acids andr values for most pairs of relationships were even higher than those obtained from the 1992 crop. Presented at the 85th AOCS Annual Meeting and Expo, Atlanta, Georgia, May 8–12, 1994.  相似文献   

9.
The ratio of oleic acid to the combined value of linoleic and α-linolenic acids determines the oxidative stability, and the ratio of linoleic acid to α-linolenic acid is the key to the nutritional value of soybean oil. The present study was conducted to identify genomic regions associated with oleic, linoleic, and α-linolenic acids in recombinant inbred lines (RIL), developed from LSb1 × NRC7, across 5 cropping years. These RIL were genotyped using 105 polymorphic SSR markers across soybean genome and analyzed for fatty acid composition. SSR markers, namely, Satt245 (LGp M), Satt556 (LGpB2), Sat_042 (LGp C1), Staga002 (LGp D1b), Satt684 (LGp A1), and AI856415 (LGpD1b) showed significant (P < 0.05) association with oleic acid for all the 5 years, though this association was weak in the years when the growing temperature during active seed formation stage was high. Quantitative trait loci (QTL) linked to Satt684 (LGp A1), Satt556 (LGp B2), Sat_042 (LGp C1), and AI856415 (LGp D1b) showed pleiotropic influence on the levels of unsaturated fatty acids. Complementation of favorable QTL from LSb1 and NRC7 generated 60% oleic acid and less than 4% α-linolenic acid RIL, stable across 5 cropping years. New SSR markers, namely, Satt245, AI856415, and Staga002 identified to be associated with different unsaturated fatty acids may be useful in improving the efficiency of marker-assisted breeding for enhancing the monounsaturated to polyunsaturated fatty acids ratio of soybean oil.  相似文献   

10.
The composition and physicochemical properties of pecan (Carya illinoensis) kernels and oils from different native trees of the central region of Mexico were investigated. The main compositional characteristic of the kernel was the high lipid content (70–79% w/w on dry basis) with elevated concentration of oleic acid (55–75% w/w). The results confirmed the relationship in the biosynthesis of linoleic and linolenic acids from oleic acid existing in oilseeds. Our results indicate that in pecans such relationship is a function of pecan tree age. The proportion of oleic, linoleic, and linolenic fatty acids determined the oxidative stability, viscosity, and melting/crystallization behavior of pecan oil. In general, these properties in pecan oils were similar or superior to extra-virgin olive oil and unrefined sesame oil. Although all native pecan oils studied showed a significant concentration of oleic acid, a particular group of native Mexican pecan trees produces an oil with a fatty acid composition with the nutritional appeal that consumers demand nowadays (i.e., very high oleic acid, 60–75%), with excellent natural oxidative stability (i.e., induction time for oxidation between 8.5 and 10.8 h), and substantially higher concentrations of α-, γ-, and δ-tocopherol than in pecan varieties previously reported in the literature.  相似文献   

11.
Fresh raspberry (Rubus idaeus), cultivar Willamette, was freeze‐dried (lyophilization). A byproduct of lyophilization is “fine dust” of raspberry consisting of finely ground raspberry fruit body and seed. The seeds were separated. The seed oil was isolated and its physical and chemical characteristics were determined. Parameters that characterize the seed and quality of the oil were examined, including fatty acid composition, oxidative stability under different storage conditions, and radical‐scavenging activity. The fatty acid composition was determined by GC/FID and the contents of the dominant fatty acids were found as: oleic 16.92%, linoleic 54.95%, and α‐linolenic acid 23.97%. The oxidative stability of the oil was poor. The induction period by Rancimat test at 100 °C was 5.2 h. The radical‐scavenging activity is similar to that of resveratrol [1,3‐benzenediol 5‐(1E‐2‐4‐hydroxy‐phenyl‐ethyl)]. Although this product is used in the candy industry, it would be far more useful if raspberry oil of satisfactory quality could be extracted. This paper demonstrates that sifted lyophilized seeds can be used for the extraction of oils. This process allows for maximal usage of the byproducts, reduces losses and it increases the development of new products.  相似文献   

12.
The oil extracted from the fat-storage organ (fat body) of the bullfrog (Rana catesbeiana) was characterized for its fatty acid composition. The main fatty acids were palmitic (18.1%), stearic (4.1%), myristic (2.7%), oleic (31.7%), and linoleic (12.9%) acids. Long-chain polyunsaturated fatty acids were also present in significant amounts, i.e., eicosapentaenoic (1.5%) and docosahexaenoic (4.7%), and were probably derived from the fish meal content of the diet. A partially fractionated oil was extracted from the homogenized and frozen fat body with an oleic acid content of 43.2%. The natural alkaloid boldine, added at 0.5 mg/g oil level, improved the oxidative stability by a factor ranging from 1.7 to 2.4, as assessed by the Oil Stability Index method between 90 and 110°C. The stabilization effect of boldine was higher than that of naringenin, morin, and quercitin and for the synthetic antioxidant butylated hydroxytoluene at the same concentration level.  相似文献   

13.
Some chemical processes utilizing oleic safflower oil   总被引:1,自引:0,他引:1  
Oleic safflower seed (UC-1) produces an oil containing approximately 80% oleic acid and 12% linoleic acid. The oil is a source of high quality oleic acid, and fatty acids from the oil may be used without further separation in some applications where technical oleic acid is now used, since oleic safflower free fatty acids have a a higher oleic acid content than good commercial grades of oleic acid. A high purity oleic acid can be produced by urea fractionation. Ozonization of the oil followed by reductive cleavage yields pelargonaldehyde and nearly colorless aldehyde oils. Ozonization of a crude mixture of oleic safflower acids followed by oxidative cleavage provides high yields of azelaic acid and pelargonic acid. In contrast, ozonization of free fatty acids from polyunsaturated vegetable oils produces azelaic acid and mixtures of lower molecular weight carboxylic acids with smaller amounts of pelargonic acid. Furtherore, ozone consumption is lower and reaction time is shorter when oleic safflower acids are used in place of more highly unsaturated fatty acids.  相似文献   

14.
The oxidative stability of soybean oil triacylglycerols (TAG) obtained from genetically modified soybeans was determined before and after chemical randomization. Soybean oil oxidative studies were carried out under static oxygen headspace at 60°C in the dark and oxidative deterioration was monitored by peroxide value, monometric and oligomeric oxidation products, and volatile compounds. Randomization of the soybean oil TAG improved the oxidative stability compared to the natural soybean oil TAG. Oxidative stability was improved by three factors. Factor one was the genetic modification of the fatty acid composition in which polyunsaturated acids (such as linolenic and linoleic acids) were decreased and in which monounsaturated fatty acids (such as oleic) and saturated acids (palmitic and stearic) were increased. Factor two was the TAG compositional modification with a decrease in linolenic and linoleic-containing TAG and an increase in TAG with stearic and palmitic acids in combination with oleic acid. Factor three was the TAG structure modification accomplished by an increase in saturated fatty acids and a decrease in linoleic and linolenic acids at the glycerol moiety carbon 2. Presented at the AOCS Annual Meeting & Expo, Chicago, IL, May 10–13, 1998.  相似文献   

15.
Seeds of six safflower (C. tinctorius L.) genotypes and 19 accessions of two wild species were analyzed for oil and fatty acid composition. Oil content ranged from 29.20 to 34.00, 20.04 to 30.80 and 15.30 to 20.80% in C. tinctorius, C. oxyacantha Bieb. and C. lanatus L., respectively. The main fatty acids of oleic, linoleic, palmitic and stearic acids composed 96–99% of the total fatty acids in all species. The sum of myristic, palmitoleic, arachidic, and behenic fatty acids in oil of the species ranged from 0.43 to 0.57%. The oleic acid in seed oil of C. tinctorius, C. oxyacantha and C. lanatus ranged from 12.24 to 15.43, 14.11 to 19.28 and 16.70 to 19.77%, respectively. The corresponding ranges for linoleic acid were 71.05 to 76.12, 63.90 to 75.43 and 62.47 to 71.08%. Palmitic acid in seed oil varied from 5.48 to 7.59% in C. tinctorius, 6.09 to 8.33% in C. oxyacantha and 7.44 to 8.78% in C. lanatus. The stearic acid of the seed oil showed a variation of 1.72 to 2.86, 2.50 to 4.87 and 3.14 to 4.79% in genotypes of these species, respectively. The fatty acids composition of oil among the cultivated and wild species were not considerably different, indicating that seed oil of the wild safflower is possibly suitable for human consumption and industrial purposes.  相似文献   

16.
We aimed at investigating oxidative stability and changes in fatty acid and tocopherol composition of extra virgin olive oil (EVOO) in comparison with refined seed oils during short‐term deep‐frying of French fries, and changes in the composition of the French fries deep‐fried in EVOO. EVOO samples from Spain, Brazil, and Portugal, and refined seed oils of soybean and sunflower were studied. Oil samples were used for deep‐frying of French fries at 180 °C, for up to 75 min of successive frying. Tocopherol and fatty acid composition were determined in fresh and spent vegetable oils. Tocopherol, fatty acid, and volatile composition (by SPME–GC–MS) were also determined in French fries deep‐fried in EVOO. Oil oxidation was monitored by peroxide, acid, and p‐anisidine values, and by Rancimat after deep‐frying. Differential scanning calorimetry (DSC) analysis was used as a proxy of the quality of the spent oils. EVOOs presented the lowest degree of oleic and linoleic acids losses, low formation of free fatty acids and carbonyl compounds, and were highly stable after deep‐frying. In addition, oleic acid, tocopherols, and flavor compounds were transferred from EVOO into the French fries. In conclusion, EVOOs were more stable than refined seed oils during short‐term deep‐frying of French fries and also contributed to enhance the nutritional value, and possibly improve the flavor, of the fries prepared in EVOO.  相似文献   

17.
The physicochemical properties of seed and seed oil obtained from the native black mulberry (Morus nigra L.) were investigated in 2008 and 2009. The results showed that the seed consisted of 27.5–33% crude oil, 20.2–22.5% crude protein, 3.5–6% ash, 42.4–46.6% carbohydrate and 112.2–152.0 mg total phenolics/100 g. Twenty different fatty acids were determined, with the percentages varying from 0.02% myristic acid (C14:0) to 78.7% linoleic acid (C18:2). According to the GC analysis of fatty acid methyl esters, linoleic acid (C18:2), followed by palmitic acid (C16:0), oleic acid (C18:1) and stearic acid (C18:0) were the major fatty acids, which together comprised approximately 97% of the total identified fatty acids. High C18:2 content (average 73.7%) proved that the black mulberry seed oil is a good source of the essential fatty acid, linoleic acid. Linolenic acid (C18:3) was also found in a relatively lower amount (0.3–0.5%). The α-tocopherol content was found to be between 0.17 and 0.20 mg in 100 g seed oil. The main sterols in the mulberry seed oil were β-sitosterol, Δ5-avenasterol, Δ5, 23-stigmastadienol, clerosterol, sitosterol and Δ5, 24-stigmastadienol. The present study stated that the native black mulberry seed oil can be used as a nutritional dietary substance and has great usage potential.  相似文献   

18.
In view of the growing demand for vegetable oil, currently exploration of some non‐conventional oils is of great concern. This study firstly analyzed the contents of fatty acids, phytosterols, and tocopherols in Catalpa ovata seed oil collected from four different Provinces in China. Then the composition of flavonoids as well as their antioxidant activities in defatted seed meal was determined. The results showed that the relative oil content in C. ovata seeds ranged from 24.0 to 36.0 % and seed oil was mainly composed of fatty acids linoleic acid (43.4–50.1 %), α‐linolenic acid (23.8–24.4 %), and oleic acid (13.1–16.2 %). The content of unsaturated fatty acids was up to 85.0 %. Sterol in seed oil mainly contained campesterol, stigmasterol, and β‐sitosterol. β‐sitosterol accounted for 74.0 % of the total sterol. The tocopherol content was 173.0–225.7 mg/100 g. Defatted seed meal from Hubei Province showed the highest content of total flavonoids (11 mg/g) and the strongest activities for DPPH radicals scavenging, ABTS radicals scavenging, and ferric reducing antioxidant power compared with other defatted seed meal in this study. Seven flavonoids were identified from C. ovata seed meal. These results suggest that C. ovata seeds may be developed as a new source of oil and can also be properly used in pharmaceuticals and cosmetics.  相似文献   

19.
Summary THE fatty acid compositions of twelve samples of oil representing a number of different types and varieties of tobacco were determined by the thiocyanometric method. The samples were remarkably uniform in composition, containing on the average 75% linoleic, 15% oleic, and 10% saturated acids. Spectrophotometric determination of the linoleic acid content of two samples of oil gave values 3.0 and 5.4% higher than those by the thiocyanometric method. A more complete investigation of the fatty acid constituents of one sample of flue-cured tobacco seed oil was carried out by analysis of fractions obtained by distillation of the methyl esters and by low-temperature crystallization of the distilled ester fractions. The composition calculated from these analyses agreed well with that determined from analysis directly on the oil. The saturated acids consisted of palmitic and stearic acids, the proportions being about 7 and 3%, respectively, of the total fatty acids. Analysis of this sample of oil showed that it contained 0.043% of tocopherol. From its composition, tobacco seed oil would seem to be particularly suitable for the manufacture of nonyellowing alkyds or for the preparation of technical linoleic acid. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, United States Department of Agriculture.  相似文献   

20.
The variation in oil content, oil yield and fatty acid compositions of 103 sesame landraces was investigated. The landraces varied widely in their oil quantity and quality. The oil content varied between 41.3 and 62.7%, the average being 53.3%. The percentage content of linoleic, oleic, palmitic and stearic acids in the seed oil ranged between 40.7–49.3, 29.3–41.4, 8.0–10.3 and 2.1–4.8%, respectively. Linolenic and arachidic acids were the minor constituents of the sesame oil. Linoleic and oleic acids were the major fatty acids of sesame with average values of 45.7 and 37.2%, respectively. The total means of oleic and linoleic acids as unsaturated fatty acids of sesame were about 83% which increases the suitability of the sesame oil for human consumption. The superiority of the collection was observed in oil content. The oil content of a few accessions was above 60%, proving claims that some varieties of sesame can reach up to 63% in oil content. The accessions with the highest oil content were relatively richer in the linoleic acid content while there were some landraces in which linoleic and oleic acid contents were in a proportion of almost 1:1. The results obtained in this study provide useful background information for developing new cultivars with a high oil content and different fatty acid compositions. Several accessions could be used as parental lines in breeding programmes aiming to increase sesame oil quantity and quality.  相似文献   

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