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1.
Plant oils rich in oxygenated fatty acids (FAs) are of interest as renewable raw materials for industry. Previous studies reported unusual oxygenated FAs in the seed lipids of Plantago major and P. ovata. To determine if oxygenated FAs are a common component of Plantago seed oils, seed fatty acyl quality and quantity were determined for 23 Plantago species. Fatty acyl content, as a percentage of dry weight, ranged from 4.9 % in P. sempervirens to 18.8 % in P. coronopus. Oxygenated FAs were a frequent, but not ubiquitous component of Plantago seed lipids, reaching a level of almost 15 % in the seeds of P. nivalis. The oxygenated FAs were identified as isoricinoleic acid (9-hydroxy-cis-12-octadecenoic acid, IR) and 9-oxo-cis-12-octadecenoic acid (OX). When present, most species contained both IR and OX. FAs containing oxo groups have not been reported as components of the seed oil of other plant species that synthesize IR or ricinoleic acid (12-hydroxy-cis-9-octadecenoic acid), suggesting unique aspects to the pathway of oxygenated FA biosynthesis in Plantago. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) demonstrated that IR and OX are components of triacylglycerol, and triacylglycerol estolides are a minor component of the seed oil of P. lanceolata with secondary acylation by oxygenated FAs.  相似文献   

2.
Non-Edible Plant Oils as New Sources for Biodiesel Production   总被引:1,自引:0,他引:1  
Due to the concern on the availability of recoverable fossil fuel reserves and the environmental problems caused by the use those fossil fuels, considerable attention has been given to biodiesel production as an alternative to petrodiesel. However, as the biodiesel is produced from vegetable oils and animal fats, there are concerns that biodiesel feedstock may compete with food supply in the long-term. Hence, the recent focus is to find oil bearing plants that produce non-edible oils as the feedstock for biodiesel production. In this paper, two plant species, soapnut (Sapindus mukorossi) and jatropha (jatropha curcas, L.) are discussed as newer sources of oil for biodiesel production. Experimental analysis showed that both oils have great potential to be used as feedstock for biodiesel production. Fatty acid methyl ester (FAME) from cold pressed soapnut seed oil was envisaged as biodiesel source for the first time. Soapnut oil was found to have average of 9.1% free FA, 84.43% triglycerides, 4.88% sterol and 1.59% others. Jatropha oil contains approximately 14% free FA, approximately 5% higher than soapnut oil. Soapnut oil biodiesel contains approximately 85% unsaturated FA while jatropha oil biodiesel was found to have approximately 80% unsaturated FA. Oleic acid was found to be the dominant FA in both soapnut and jatropha biodiesel. Over 97% conversion to FAME was achieved for both soapnut and jatropha oil.  相似文献   

3.
Myrcia is one of the largest genera of the economically important family Myrtaceae. Some of the species are used in folk medicine, such as a group known as “pedra-hume-caá” or “pedra-ume-caá” or “insulina vegetal” (insulin plant) that it is used for the treatment of diabetes. The species are an important source of essential oils, and most of the chemical studies on Myrcia describe the chemical composition of the essential oils, in which mono- and sesquiterpenes are predominant. The non-volatile compounds isolated from Myrcia are usually flavonoids, tannins, acetophenone derivatives and triterpenes. Anti-inflammatory, antinociceptive, antioxidant, antimicrobial activities have been described to Myrcia essential oils, while hypoglycemic, anti-hemorrhagic and antioxidant activities were attributed to the extracts. Flavonoid glucosides and acetophenone derivatives showed aldose reductase and α-glucosidase inhibition, and could explain the traditional use of Myrcia species to treat diabetes. Antimicrobial and anti-inflammatory are some of the activities observed for other isolated compounds from Myrcia.  相似文献   

4.
The fatty acid profile of kenaf (Hibiscus cannabinus L.) seed oil has been the subject of several previous reports in the literature. These reports vary considerably regarding the presence and amounts of specific fatty acids, notably (12,13-epoxy-9(Z)-octadecenoic (epoxyoleic) acid, but also cyclic (cyclopropene and cyclopropane) fatty acids. To clarify this matter, two kenaf seed oils (from the Cubano and Dowling varieties of kenaf) were investigated regarding their fatty acid profiles. Both contain epoxyoleic acid, the Cubano sample around 2 % and the Dowling sample 5-6 % depending on processing. The cyclic fatty acids malvalic and dihydrosterculic were identified in amounts around 1 %. Trace amounts of sterculic acid were observed as were minor amounts of C17:1 fatty acids. The results are discussed in the context of the fatty acid profiles of other hibiscus seed oils.  相似文献   

5.
A novel process has been described recently for the preparation of hydroxylated fatty acids (HOFA) and HOFA methyl esters from plant oils. HOFA methyl esters prepared from conventional and alternative plant oils were characterized by various chromatographic methods (thin-layer chromatography, high-performance liquid chromatography, and gas chromatography) and gas chromatography-mass spectrometry as well as1H and13C nuclear magnetic resonance spectroscopy. HOFA methyl esters obtained fromEuphorbia lathyris seed oil, low-erucic acid rapeseed oil, and sunflower oil contain as major constituents methylthreo-9,10-dihydroxy octadecanoate (derived from oleic acid) and methyl dihydroxy tetrahydrofuran octadecanoates, e.g., methyl 9,12-dihydroxy-10,13-epoxy octadecanoates and methyl 10,13-dihydroxy-9,12-epoxy octadecanoates (derived from linoleic acid). Other constituents detected in the products include methyl esters of saturated fatty acids (not epoxidized/derivatized) and traces of methyl esters of epoxy fatty acids (not hydrolyzed). The products that contain high levels of monomeric HOFA may find wide application in a variety of technical products.  相似文献   

6.
The aim of this work was to establish the richness in γ-linolenic acid (GLA, 18:3n-6) and stearidonic acid (SDA, 18:4n-3) of the seed oil of several restricted-range Boraginaceae species, in a search for new valuable oils as advantageous alternatives to the commercially available sources of both polyunsaturated fatty acids. To this end, seeds of selected Boraginaceae species were collected and analyzed. The highest GLA contents (% total fatty acids) were found in the seed oils of Symphytum caucasicum M.Bieb. (22.9 %), Anchusa undulata subsp. undulata (Ten.) Cout. (22.0 %), Anchusa puechii Valdés (20.0 %), Glandora nitida Thomas (19.2 %), Echium pininana Webb & Berth. (17.1 %) and Pentaglottis sempervirens (L.) L. H. Bailey (17.0 %). With regard to SDA, the highest percentage was found in the seed oil of Echium cantabricum (M. Laínz) Fdez. Casas & M. Laínz (14.7 %), followed by Lappula patula (Lehm.) Asch ex Gürke (13.6 %). It is noticeable that several GLA-enriched species stand under a great threat of extinction, thus revealing the importance of the preservation of the natural ecosystems for endangered species.  相似文献   

7.
The genus Chrysodracon has six endemic species in the Hawaii Islands. Chrysodracon hawaiiensis is endemic to Hawaii Island and was described as a distinct species in 1980. It was listed as an endangered species on the International Union for the Conservation of Nature and Natural Resources (IUCN) Red List in 1997. This woody plant species was, at one time, common in exposed dry forests, but it became very rare due to grazing pressure and human development. The tree species Chrysodracon auwahiensis (C. auwahiensis), endemic to Maui and Molokai, still has large adult populations in dry lands of the islands, but unfortunately no regeneration from seed has been reported in those areas for many years. The two endemic species were examined using the molecular technique of random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) to determine the genetic structure of the populations and the amount of variation. Both species possess similar genetic structure. Larger and smaller populations of both species contain similar levels of genetic diversity as determined by the number of polymorphic loci, estimated heterozygosity, and Shannon’s index of genetic diversity. Although population diversity of Chrysodracon hawaiiensis (C. hawaiiensis) is thought to have remained near pre-disturbance levels, population size continues to decline as recruitment is either absent or does not keep pace with senescence of mature plants. Conservation recommendations for both species are suggested.  相似文献   

8.
Camellia tenuifloria is an indigenous Camellia species used for the production of camellia oil in Taiwan. This study investigated for the first time the potential antioxidant, anti-tyrosinase and anti-inflammatory activities of oil production byproducts, specifically those of the fruit shell, seed shell, and seed pomace from C. tenuifloria. It was found that the crude ethanol extract of the seed shell had the strongest DPPH scavenging and mushroom tyrosinase inhibitory activities, followed by the fruit shell, while seed pomace was the weakest. The IC50 values of crude extracts and fractions on monophenolase were smaller than diphenolase. The phenolic-rich methanol fraction of seed shell (SM) reduced nitric oxide (NO) production, and inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. It also repressed the expression of IL-1β, and secretion of prostaglandin E2 (PGE2) and IL-6 in response to LPS. SM strongly stimulated heme oxygenase 1 (HO-1) expression and addition of zinc protoporphyrin (ZnPP), a HO-1 competitive inhibitor, reversed the inhibition of NO production, indicating the involvement of HO-1 in its anti-inflammatory activity. The effects observed in this study provide evidence for the reuse of residues from C. tenuifloria in the food additive, medicine and cosmetic industries.  相似文献   

9.
Background: The incidence of fungal infections, especially those caused by Candida yeasts, has increased over the last two decades. However, the indicated therapy for fungal control has limitations. Hence, medicinal plants have emerged as an alternative in the search for new antifungal agents as they present compounds, such as essential oils, with important biological effects. Published data demonstrate important pharmacological properties of the essential oil of Cymbopogon nardus (L.) Rendle; these include anti-tumor, anti-nociceptive, and antibacterial activities, and so an investigation of this compound against pathogenic fungi is interesting. Objective: The aim of this study was to evaluate the chemical composition and biological potential of essential oil (EO) obtained from the leaves of C. nardus focusing on its antifungal profile against Candida species. Methods: The EO was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS). Testing of the antifungal potential against standard and clinical strains was performed by determining the minimal inhibitory concentration (MIC), time-kill, inhibition of Candida albicans hyphae growth, and inhibition of mature biofilms. Additionally, the cytotoxicity was investigated by the IC50 against HepG-2 (hepatic) and MRC-5 (fibroblast) cell lines. Results: According to the chemical analysis, the main compounds of the EO were the oxygen-containing monoterpenes: citronellal, geranial, geraniol, citronellol, and neral. The results showed important antifungal potential for all strains tested with MIC values ranging from 250 to 1000 μg/mL, except for two clinical isolates of C. tropicalis (MIC > 1000 μg/mL). The time-kill assay showed that the EO inhibited the growth of the yeast and inhibited hyphal formation of C. albicans strains at concentrations ranging from 15.8 to 1000 μg/mL. Inhibition of mature biofilms of strains of C. albicans, C. krusei and C. parapsilosis occurred at a concentration of 10× MIC. The values of the IC50 for the EO were 96.6 μg/mL (HepG-2) and 33.1 μg/mL (MRC-5). Conclusion: As a major virulence mechanism is attributed to these types of infections, the EO is a promising compound to inhibit Candida species, especially considering its action against biofilm.  相似文献   

10.
Sesame seed (Sesamum indicum L.) is a rich source of furofuran lignans with a wide range of potential biological activities. The major lignans in sesame seeds are the oil‐soluble sesamin and sesamolin, as well as glucosides of sesaminol and sesamolinol that reside in the defatted sesame flour. Upon refining of sesame oil, acid‐catalyzed transformation of sesamin to episesamin and of sesamolin to epimeric sesaminols takes place, making the profile of refined sesame oils different from that of virgin oils. In this study, the total lignan content of 14 sesame seeds ranged between 405 and 1178 mg/100 g and the total lignan content in 14 different products, including tahini, ranged between 11 and 763 mg/100 g. The content of sesamin and sesamolin in ten commercial virgin and roasted sesame oils was in the range of 444–1601 mg/100 g oil. In five refined sesame oils, sesamin ranged between 118 and 401 mg/100 g seed, episesamin between 12 and 206 mg/100 g seed, and the total contents of sesaminol epimers between 5 and 35 mg/100 g seed, and no sesamolin was found. Thus, there is a great variation in the types and amounts of lignans in sesame seeds, seed products and oils. This knowledge is important for nutritionists working on resolving the connection between diet and health. Since the consumption of sesame seed products is increasing steadily in Europe and USA, it is important to include sesame seed lignans in databases and studies pertinent to the nutritional significance of antioxidants and phytoestrogens. It is also important to differentiate between virgin, roasted and refined sesame oils.  相似文献   

11.
Vegetable oils that are important to the chemical industry include both edible and industrial oils, which contribute 24% and 13.5%, respectively, compared to 55% for tallow, to the preparation of surfactants, coatings, plasticizers, and other products based on fats and oils. Not only the oils themselves but also the fatty acids recovered from soapstock represent a several billion pound resource. Coconut oil is imported to the extent of 700-1,000 million pounds per year. Its uses are divided about equally between edible and industrial applications. Safflower oil has a relatively small production, but 15–25% of the oil goes into industrial products. Soybean oil, the major edible oil of the world, is produced in the United States at the rate of 11,000 million pounds per year with more than 500 million pounds going into industrial uses, representing 5% of the total production. Castor oil is imported to the extent of about 100 million pounds per year. Linseed oil production has declined drastically over the last 25 years but still amounts to about 100 million pounds per year. Oiticica and tung oils are imported in lesser amounts than castor and linseed oils. New crops that have industrial potential, as well as the traditional vegetable oil crops, include seed oils from crambe,Limnanthes, Lesquerella, Dimorphotheca, Vernonia, andCuphea plants. Crambe oil contains up to 65% erucic acid. Oil fromLimnanthes contains more than 95% of fatty acids above C18.Lesquerella oil contains hydroxy unsaturated acids resembling ricinoleic acid from castor oil.Dimorphotheca oil contains a conjugated dienol system.Vernonia oils contain as much as 80% epoxy acids. TheCuphea oils contain a number of short chain fatty acids. Of these, crambe,Limnanthes, andVernonia are probably the most developed agronomically. Competition between vegetable oils and petrochemicals for the traditional fats and oil markets has been marked over the past 25 years, but prices for petrochemicals have accelerated at a greater rate than those for vegetable oils; and, it is now appropriate to reexamine the old as well as the new markets for fatty acids.  相似文献   

12.
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   

13.
Seeds of nine Central Asian species of Boraginaceae were investigated for the first time for their oil content and for the fatty acid composition of their seed oils by capillary gas chromatography. Levels of γ-linolenic acid ranged from 6.6 to 13.0% and levels of stearidonic acid ranged from 2.4 to 21.4% of total seed fatty acids. The seed oil ofHackelia deflexa exhibited the highest stearidonic acid content (21.4%) that has been found so far in nature. Other high contents of this fatty acid were in threeLappula species (17.2 to 18.1%). Seed oils ofCynoglossum divaricatum andAmblynotus rupestris contain considerable amounts ofcis-11-eicosenoic (5.3 to 5.8%) andcis-13-docosenoic acid (7.0 to 9.7%) besides γ-linolenic (10.2 to 13.0%) and stearidonic acid (2.4 to 6.5%), which distinguish these oils from those of other Boraginaceae genera. This paper was presented as a poster at 10th Minisymposium and Workshop on Plant Lipids, Sept. 3–6, 1995, in Berne, Switzerland.  相似文献   

14.
The occurrent of petroselinic acid (18∶1Δ6cis) in seed oils was believed to be limited to the Umbelliferae or Apiaceae, and a few other members of the Umbelliflorae. A major occurrence of petroselinic acid outside the Umbelliflorae must therefore be regarded as highly unusual and surprising. The seed oil of Geranium sanguineum, a member of the family Geraniaceae, has now been found to contain petroselinic and vernolic acids as major FA in its seed oil TAG. These unusual FA have not been reported previously as constituents of Geraniaceae seed oils. The structure and composition of the seed oil FA from G. sanguineum were determined by combined use of chromatographic (TLC, capillary GLC) and spectroscopic (IR, GC-MS) techniques. The double-bond position in petroselinic acid was located unambiguously by the characteristic mass fragmentation of its dimethyldisulfide (DMDS) adduct. The epoxy FA was identified as vernolic acid by co-chromatography and by the mass fragments formed during GC-MS of the products of the epoxy ring-opening reaction with BF3 in methanol.  相似文献   

15.
The photoprotective skincare products are in high demand to meet the consumer market with concern on skin health. Seed oils are commonly used as ingredients in many cosmetic products due to their natural antioxidants and now being increasingly recognized for their effects on skin health and photoprotection. This article briefly reviews the application of seed oils in sunscreen development focusing on the antioxidants that contribute to photoprotection, thus preventing UV-induced erythema and photoaging. The addition of seed oils that contain specific natural bioactive compounds was discussed in the review. Besides that, seed oils acting in molecular pathways that benefit photoprotection were also summarized. Seed oils (pomegranate seed oil, castor oil, cocoa butter, jojoba oil, rosehip oil, grapeseed oil, kenaf seed oil, and pumpkin seed oil) utilization have high potential to act as natural UV filters and at the same time help in skin repairing. The seed oils contributed beneficial properties to the sunscreen formulation due to their synergistic effect with antioxidants, antiaging properties, anti-inflammatory effect, and potential hormetic effect. The finding of specific bioactive compound from seed oils provides a better understanding of the contribution of seed oils in sunscreen formulation.  相似文献   

16.
  1. The pigmentation of cooked cottonseed has been shown to depend principally upon the moisture content and period of heating of the seed.
  2. Several samples of crude hydraulic-pressed and screw-pressed oils produced under known processing conditions were found to differ markedly from each other with respect to their original colors and refining characteristics.
  3. The screw-pressed crude oils were more deeply colored and contained one principal pigment, whereas the hydraulic-pressed oils contained two principal pigments.
  4. The absence of significant amounts of gossypol in the crude oils has been demonstrated by means of a new technic for the quantitative isolation of gossypol.
  5. The crude oil pigments differed from gossypol, but like gossypol, they were removed during alkali refining.
  6. The pigmentation of the crude oils has been shown to depend principally upon the pigmentation of the original seed and the moisture content of the seed during cooking.
  7. On the basis of their absorption spectra it has been deduced that the alkali-refined hydraulic-pressed oils contain two to three pigments originally present in the crude oils whereas the alkali-refined serewpressed oils contain these same pigments as well as a large number of decomposition products of the principal crude oil pigment.
  相似文献   

17.
Tocopherol and Tocotrienol Composition of Seed Oils of Some Representatives of the Apiaceae Family Fatty oils of a number of species from the family Apiaceae are obtained as the by-products of essential oil production from Apiaceae seeds. These oils contain high levels of petroselinic acid and some of these plant species, for example Coriandrum, have been used in plant breeding as a renewable resource. The fatty oils, however, also contain high levels of tocopherols and tocotrienols, a main component being γ-tocotrienol. Because of this, the seed oils of fennel and other Apiaceae show a high oxidative stability. The tocopherol and tocotrienol composition of these seed oils was investigated using HPLC on silica columns with fluorescence detection. Some of these oils contained total tocopherol levels that were higher than those of germ oils.  相似文献   

18.
Prafulla D. Patil 《Fuel》2009,88(7):1302-1306
The non-edible vegetable oils such as Jatropha curcas and Pongamia glabra (karanja) and edible oils such as corn and canola were found to be good viable sources for producing biodiesel. Biodiesel production from different edible and non-edible vegetable oils was compared in order to optimize the biodiesel production process. The analysis of different oil properties, fuel properties and process parameter optimization of non-edible and edible vegetable oils were investigated in detail. A two-step and single-step transesterification process was used to produce biodiesel from high free fatty acid (FFA) non-edible oils and edible vegetable oils, respectively. This process gives yields of about 90-95% for J. curcas, 80-85% for P. glabra, 80-95% for canola, and 85-96% for corn using potassium hydroxide (KOH) as a catalyst. The fuel properties of biodiesel produced were compared with ASTM standards for biodiesel.  相似文献   

19.
Food products incorporating oil rich in polyunsaturated fatty acids are known to become easily rancid. In order to delay the process of oxidation there is a need to develop analytical methods that accurately estimate the antioxidant potential of the oil and predict its oxidative stability. Thus, the present work investigated Lepidium sativum and Nigella sativa seed oil as a source of natural antioxidants. Further, the effect of blending the two oils on the oxidative stability of the unsaturated L. sativum oil was also studied. Electro-paramagnetic resonance (EPR) spectroscopy showed 100 % 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical quenching by both the oils at a concentration of 5 % w/v oil in benzene thereby establishing the anti-oxidant potential of both the oils. Differential scanning calorimetry (DSC) studies showed addition of N. sativa oil to L. sativum oil enhanced its oxidation onset temperature, a relevant indicator of oil stability, thereby making N. sativa a source of natural antioxidants. Consequently, the DSC and EPR spectroscopy techniques so developed can find application in shelf life studies of oil.  相似文献   

20.
Fifteen seed oils from nine plant families have been examined. Oleic acid is the major component in all the oil samples, maximum being in Amaranthus tricolor (91.0%), except in the seed oil of Physalis maxima. All the samples contain arachidic and behenic acids. The oil samples from Ipomoea species and from Physalis maxima contain the lower fatty acids (caprylic and capric). Linolenic acid is found in eleven samples and lauric acid in all the seed oils except the seed oil of Celosia cristata.  相似文献   

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