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1.
The feasibility of producing biodiesel from Idesia polycarpa var. vestita fruit oil was studied. A methyl ester biodiesel was prepared from refined I. polycarpa fruit oil using methanol and potassium hydroxide (KOH) in an alkali-catalyzed transesterification process. The experimental variables investigated in this study were catalyst concentration (0.5–2.0 wt.% of oil), methanol/oil molar ratio (4.5:1 to 6.5:1), temperature (20–60 °C) and reaction time (20–60 min). A maximum yield of over 99% of methyl esters in I. polycarpa fruit oil biodiesel was achieved using a 6:1 molar ratio of methanol to oil, 1.0% KOH (% oil) and reaction time for 40 min at 30 °C. The properties of I. polycarpa fruit oil methyl esters produced under optimum conditions were also analyzed for specifications for biodiesel as fuel in diesel engines according to China Biofuel Systems Standards. The fuel properties of the I. polycarpa fruit oil biodiesel obtained are similar to the No. 0 light diesel fuel and most of the parameters comply with the limits established by specifications for biodiesel.  相似文献   

2.
Jatropha curcas oil (JCO) has a high content of free fatty acids and has been used extensively as a feedstock in biodiesel production. In the present study, the transesterification reaction of JCO to Jatropha curcas methyl ester (biodiesel) was performed in a continuous pulsed loop reactor under atmospheric conditions. The JCO was pre-treated prior to the reaction to reduce the free fatty acid content to below 1% (w/w). The operating parameters of the loop reactor were optimised based on the conversion of the JCO to Jatropha curcas biodiesel and included reaction temperature, molar ratio of oil to MeOH, reaction time and oscillation frequency. The findings show that the highest reaction conversion of 99.7% (w/w) was achieved using KOH catalyst and 98.8% conversion was obtained using NaOCH3 catalyst. The optimal operating conditions were a molar ratio of 6:1, an oscillation frequency of 6 Hz, temperature of 60 °C, feedstock FFA content of 0.5% (w/w) and only 10 min of reaction time. As a commercial commodity, the physical properties of biodiesel were analysed, and they compared well with the characteristics of fossil-based diesel fuel.  相似文献   

3.
The chemical composition of essential oils isolated by hydrodistillation from the aerial parts of Achillea gypsicola Hub-Mor., Achillea biebersteinii Afan. and n-hexane extracts obtained from the flowers of A. gypsicola and A. biebersteinii Afan. was analyzed by GC and GC–MS. Camphor (40.17–23.56%, respectively), 1,8-cineole (22.01–38.09%, respectively), piperitone (11.29–0.37%, respectively), borneol (9.50–5.88%, respectively) and α-terpineol (1.56–5.15%, respectively) were found to be the main constituents in A. gypsicola and A. biebersteinii essential oils. Furthermore, hexane extracts of A. gypsicola and A. biebersteinii consist of mainly camphor (37.78–27.88%, respectively), 1,8-cineole (13.43–24.78%, respectively), piperitone (15.57%-tr, respectively), n-eicosane (1.61–9.68%, respectively), n-heneicosane (2.56–9.55%, respectively), n-tricosane (3.46–10.04%, respectively), linoleic acid (6.19–3.17%, respectively) and borneol (5.66–5.58%, respectively). Although the oils and extracts were characterized relatively by high content of oxygenated monoterpenes, hexane extracts of the plant samples relatively rich in n-alkanes, fatty acids and fatty acid esters as compared with the oil. The oils and hexane extracts were also tested against 12 phytopathogenic fungi and the oils found to be more toxic as compared with hexane extracts of the plant samples. A. gypsicola oil only did not inhibit the growth of Fusarium graminearum. The extracts also strongly increased the growth of Fusarium equiseti and F. graminearum. Therefore, the antifungal activity of the oils can be attributed to their relatively high content of oxygenated monoterpenes. The results of herbicidal assays of the essential oils and hexane extracts of the plant samples against five important weeds in cultivated areas, Amaranthus retroflexus L., Chenopodium album L., Cirsium arvense L. (Scop.), Lactuca serriola L. and Rumex crispus L. showed that, in particular, the oils had inhibitory effects on the seed germination and seedling growth of A. retroflexus, C. arvense and L. serriola. The hexane extracts also showed lower herbicidal effect against the weeds in comparison to that of the oils. The findings of the present study suggest that the essential oils have a potential to be used as herbicide as well as fungicide.  相似文献   

4.
Variation in oil content and fatty acid profile (FAP) of Calophyllum inophyllum; a potential biodiesel feedstock species were studied at different maturity stages and biodiesel quality parameters were estimated based on the FAP. A steady increase in oil content was observed with maturity. Variation in palmitic (16:0) and linoleic (18:2) acids followed exactly opposite trends where palmitic acid content has decreased and linoleic acid content has increased 77 days after anthesis. Oleic acid (18:1) content has shown a steady increase. Stearic acid (18:0) content remained steady up to 68 days after anthesis and then felt slightly in 77 days after anthesis. Linoleic and eicosanoic acids were found to exist in low concentrations demonstrated very little compositional variation with fruit maturity. Estimated biodiesel parameters of all maturity stages were found to comply with industrial standards. Even though 48 days after anthesis had the most ideal FAP for biodiesel production, ∼77 days after anthesis is preferred point to harvest due to higher oil content.  相似文献   

5.
Payenapara lleloneura Kurz. (Kan-zaw), an endemic medicinal plant only found in Tanintharyi Region of Myanmar, is widely used in the treatment of various cancer and different ailments. In the present research, the seeds were phytochemical investigated for their nutritional potential for their use as functional foods or novel diet oil resources. Nutritional evaluation showed that the seeds are rich in fats and carbohydrates (soluble sugars and starch). Fatty acid analyses showed that the seeds accumulate very rich α-eleostearic acid (α-ESA, 18:3Δ9cis,11trans,13trans), an important conjugated fatty acid, up to more than 70 ​% of total fatty acids. The seed oil derived from the Kan-zaw tree contains approximately 3.25 ​% β-eleostearic acid (18:3Δ9trans,11trans,13trans), an unusual conjugated fatty acid that imparts a potent anticancer application and industrially important drying qualities to Kan-zaw oil. Physicochemical properties of the Kan-zaw seeds were examined; petroleum ether (60–90 ​°C) extract of seed oils were also investigated for the saponification value, iodine value and estimation of acid value. Further, the present study investigated cytotoxic potential of ethanol, methanol, acetone, chloroform Kan-zaw seed extracts and commercial Kan-zaw oil against human cervical cancer cell line (HeLa). The Kan-zaw extracts and oil have shown significant anticancer activity on HeLa cells.  相似文献   

6.
The essential oil and fatty acid composition of two provenances of Ruta chalepensis from four organs (leaves, flowers, stems and fruits) was determined. The effect of the plant part on total fatty acid contents, essential oil yields, fatty acid and volatile constituents was significant.Fatty acid profiles varied significantly among the studied provenances and organs. Linolenic acid had the highest amount in leaves of the two provenances. From R. chalepensis, in all organs, the main fatty acids were palmitic (13.10-25.31%), followed by palmitoleic (0-15.72%), stearic (1.03-6.85%), oleic (1.90-24.04%), arachidic (0.11-4.03%), eicosatetraenoic (0.10-5.60%) and behenic (0.47-6.09%) acids. Saturated fatty acids had the highest amounts in growing wild R. chalepensis flowers, and cultivated R. chalepensis stems were characterized by the predominance of polyunsaturated fatty acids. Oil composition of all studied organs has a healthy and nutritionally value. Essential oil yields varied from 0.39% to 2.46% and showed a remarkable variation with plant organs. Thirty-six volatile compounds were identified in different analyzed essential oils; 2-undecanone, 2-nonanol and 2-dodecanone had the highest percentages.  相似文献   

7.
Lunaria annua is a biennial cruciferous oil seed crop. The seeds contain 30–35% oil, which consists of 67% long chain fatty acids (44% erucic acid, C22:1, and 23% nervonic acid, C24:1). The oil is suitable as lubricant. In addition, recent developments indicate that nervonic acid may be used as raw material for the production of a medicine against multiple sclerosis. The biennial character of Lunaria is a main constraint for an economically feasible production of Lunaria oil. The crop has to be sown early in the summer to achieve vigorous plant development required for vernalization during the winter. It would be a great advance when Lunaria could be sown later in the summer after an early harvested crop. From 1993, breeding research in Lunaria has been performed at CPRO-DLO, Wageningen, The Netherlands. A collection of 76 accessions was maintained and evaluated for agronomic performance. In 1995, a selection of 24 accessions were sown at four sowing dates, from end June until end of August and in 1996, 12 promising accessions were sown again at 15 and 30 July. Three accessions showed suitability for delayed sowing until beginning of August. Delay in sowing time caused also delay of flowering and seed ripening. Seed yield amounted to 1200 kg/ha in 1996 and 1700 kg/ha in 1997. Seed oil content varied from 30–38%. Severe infection of Albugo candida and Alternaria occurred and might have reduced seed yield in both years. Most accessions sustained severe winter frost of−17°C very well. It is concluded that within the evaluated gene pool promising variation is available to select for ability for late sowing, to improve the disease resistance and to increase seed yield and seed oil content.  相似文献   

8.
The compositions of essential oils of 19 accessions belonging to six different Achillea species, transferred from the natural habitats in 10 provinces of Iran to the field conditions, were assessed. The relationship between the leaf areas of selected accessions with their essential oil content was also investigated. Essential oil yield of dried plants obtained by hydro-distillation ranged from 0.1 to 2.7% in leaves. Results indicated a significant variation in oil composition among and within species. Total of 94 compounds were identified in 19 accessions belonging to the six species of A. millefolium, A. filipendulina, A. tenuifolia, A. santolina, A. biebersteinii and A. eriophora. The major constituents of the leaves in the tested genotypes were determined as germacrene-D, bicyclogermacrene, camphor, borneol, 1,8-cineole, spathulenol and bornyl acetate. According to the major compounds, four chemotypes were defined as: (I) spathulenol (1.64–34.31%) + camphor (0.2–15.61%) (7 accessions); (II1) germacrene-D (18.78–23.93%) + borneol (7.93–8.26%) + bornyl acetate (11.56–14.66%) (5 accessions); (II2) germacrene-D (13.28–36.28%) + bicyclogermacrene (5.93–8.4%) + 1,8-cineole (15.26–19.41%) + camphor (14.95–23.32%) (2 accessions); (III) borneol + camphor (52.04–63.27) (2 accessions); (IV) germacrene-D (45.86–69.64%) (3 accessions). The relationships of chemotypes with soil type and climatic conditions of collected regions were assessed, as probable reasons of high variations in essential oil components, and discussed.  相似文献   

9.
A genetically altered plant strain (Cuphea viscosissima VS-320) was identified which produces an oil with elevated levels of medium- and short-chain triglycerides. Previous studies have suggested that such an oil may be appropriate for use as a substitute for diesel fuel without chemical conversion of component triglycerides to methyl esters. This oil is also of interest for other industrial applications. This paper discusses the oil composition of C. viscosissima VS-320 and presents the analysis of several important alternative fuel screening properties of this oil: dynamic viscosity for shear rates of 1.617–64.69 s1 at temperatures of 25–80°C, boiling point at atmospheric pressure, temperature dependence of vapor pressure (from 40 to 760 mmHg for the 300–400°C temperature range), and heat of vaporization (ΔHv). These properties have been established as indicators of fuel performance and can be used for initial screening of possible diesel fuel substitutes. These properties are compared to those of diesel, biodiesel, and vegetable oils. Analysis of these properties suggests that further genetic development of this plant as a source of diesel fuel is warranted.  相似文献   

10.
Present study was carried out in order to assess the constituents of Adenanthera pavonina wax esters by Fourier Transform Infrared (FT-IR) spectroscopy and Gas chromatography (GC). After extraction of oil from A. pavonina seeds, wax esters were separated from oil by centrifugation and then purified through crystallization process in acetone. The white crystalline solid with melting point of 83-85 °C was initially characterized as wax esters by FT-IR. Gas chromatography with flame ionization detector (GC-FID) provided the separation of various wax esters from C34 to C48 including odd and even chain esters. C46 wax ester was found to be predominant. For separation, identification and estimation of individual constituents of fatty acid methyl esters and fatty alcohol acetates were carried out by GC-MS after saponification and derivatization of wax esters. GC-MS analysis indicated the presence of saturated methyl esters from Cl4 to C30. Predominant methyl ester was C22. Wax esters contained the saturated fatty alcohols from C14 to C28. The major alcohol was saturated C24 fatty alcohol. The results indicated that A. pavonina wax esters have potential to be used in pharmaceutical and cosmetic industry due to its better composition of long chain fatty acids and fatty alcohols.  相似文献   

11.
Japanese Spanish mackerel (JSM) (Scomberomorus niphonius) is a marine fish species containing health-beneficial polyunsaturated fatty acids (PUFAs). In the present study, the quality of JSM by-products oils extracted by supercritical CO2 (SC-CO2) and organic solvent extraction was compared in terms of physico-chemical properties of the oils. Eicosapentaenoic acid (EPA) is one of the important polyunsaturated fatty acids present in SC-CO2-extracted skin and muscle oil 5.81 ± 0.69% and 4.93 ± 0.06%, respectively. The amount of docosahexaenoic acid (DHA) in SC-CO2-extracted skin and muscle oil was 12.56 ± 0.38% and 15.01 ± 0.28%, respectively. EPA and DHA are considered as important PUFAs for the development of brain function and the prevention of coronary heart diseases. Extracted oils showed considerable antioxidant activity. In the obtained oils, atherogenic index (AI) values varied from 0.72 to 0.93 and thrombogenic index (TI) ranged from 0.75 to 0.92, which is considered an acceptable level. Fatty acid composition, bio potentiality, thermogravimetric, and vitamin D analysis showed that oils extracted from JSM by-products can be a good source of oil for application in food, pharmaceutical and cosmetic industries. Therefore, the present research revealed the potentiality of green valorisation of S. niphonius by-products as a possible sustainable approach for targeting the era of zero waste.  相似文献   

12.
生物柴油物理特性参数的估算与误差分析   总被引:1,自引:0,他引:1  
以生物柴油脂肪酸酯含量为基础,应用Matlab编制了包含15种脂肪酸酯的生物柴油物性参数预测程序,并应用所编程序估算了大豆油甲酯生物柴油的密度、表面活力、黏度和导热系数;分析比较了各种估算方法的精度.结果表明:在生物柴油密度估算中,修改Raekett方程的估算精度较高;Sastfi-Rao方法估算生物柴油低温黏度所得结果与实测值最接近,其估算精度较高;Miller方法和Macleod-Sugden关联式估算生物柴油表面张力的精度较其它几种方法高;建议在生物柴油导热系数估算中应用Sastri方法.  相似文献   

13.
Triacylglycerol-estolides are components of the storage oil of certain plant and fungal species and are generally associated with the presence of fatty acids containing hydroxyl groups. These unusual acyl-glycerols can easily go undetected when oils are analyzed by gas chromatography of fatty acid methyl esters, or by thin layer chromatography if the TAG-estolides and TAG have similar polarity. We describe the detection of TAG-estolides in intact seeds of Lesquerella lyrata and whole sclerotia of the ergot fungus Claviceps purpurea using 1H MAS-NMR for nondestructive analysis. We also conducted analysis of small amounts of oil by MALDI-TOF MS to clearly show the presence of TAG-estolides and to rapidly characterize their acyl composition. The matrix used in this work was 2,4,6-trihydroxyacetophenone (THAP) made up in sodium chloride-saturated solvent. We were able to confirm the presence of TAG-estolides with no free hydroxyl groups in the fungal oil, and TAG-estolides with free hydroxyl groups in the oil of L. lyrata. The development of a technique for the rapid identification of TAG-estolides in oil samples will simplify the detection of these novel lipids in plant and fungal species.  相似文献   

14.
Seeds of Lesquerella (Brassicaceae) contain oil rich in hydroxy fatty acids (HFA) that may be used in several industrial products such as motor oils, greases, plastics, cosmetics and pharmaceuticals. One of the most abundant HFA in the seed oil is lesquerolic acid, which is chemically similar to ricinoleic acid from castor (Ricinus communis L.). Hence, lesquerolic oil derived from a domestically grown crop could reduce the import of castor oil. In nature, Lesquerella grows in open and arid habitats, and therefore it may be an alternative arid-land crop. Domestication and breeding efforts warranted establishing a Lesquerella germplasm collection by the USDA-ARS, National Plant Germplasm System (NPGS). Seeds of 195 accessions (32 species) from the collection were evaluated for content of four different HFA (lesquerolic, densipolic, auricolic and ricinoleic) and seven other fatty acids (palmitic, palmitoleic, stearic, oleic, linolenic, linoleic and arachidic) by gas chromatography. The highest content of lesquerolic acid (C20:1 OH) was found in seeds of L. pallida and L. lindheimeri (average of >80%); the highest content of densipolic acid (C18:2 OH) was in seeds of L. perforata, L. stonensis, L. densipila, L. lyrata and L. lescurii (average>40%); the highest content of auricolic acid (C20:2 OH) was in L. auriculata and L. densiflora (average>30%), and the highest ricinoleic acid (C18:1 OH) content was in seeds of L. densipila, L. lescurii, L. lyrata and L. perforata (>10%). The highest percentages of the seven other fatty acids evaluated were oleic 23.8 (L. lasiocarpa), linoleic 18.7 (L. ludoviciana), linolenic 11.4 (L. cinerea), stearic 4.9 (L. densiflora), palmitic 4.7 (L. stoniensis), palmitoleic 2.8 (L. angustifolia), and arachidic 1.7% (L. gordonii and L. gracilis). Fatty-acid composition varied across species and accessions, and was likely influenced by the location and year the seeds were harvested, and by seed color. The NPGS Lesquerella collection could potentially serve as a valuable source of germplasm for the crop improvement.  相似文献   

15.
This work describes the mechanical and solvent extraction of Sterculia striata seed oil. It was determined that the seeds contain up to 41% in oil, which has an unusual composition. Indeed, up to 50% of the fatty acid contain cyclopropenoid ring. The oil was used as raw material to produce bio-oil and biodiesel and their physical-chemical properties were evaluated. Some of the studied physical-chemical properties of the S. striata biodiesel are in acceptable range for use as biodiesel in diesel engines, showing a promising economic exploitation of this raw material in semi-arid regions. It was also observed that the cyclopropenoid ring remains after transesterification and is decomposed during pyrolysis.  相似文献   

16.
Microalgae oil is an optimal feedstock for nutraceutical, pharmaceutical and biodiesel production, but its high levels of chlorophyll limit its large-scale application. To date, few effective approaches have been developed to remove chlorophyll from microalgae oil. The main purpose of this study was to present a preprocessing method of algae oil feedstock (Scenedesmus) to remove chlorophyll by saponification. The results showed that 96% of chlorophyll in biomass was removed. High quality orange transparent oil could be extracted from the chlorophyll reduced biomass. Specifically, the proportion of neutral lipids and saturation levels of fatty acids increased, and the pigments composition became carotenoids-based. The critical parameters of chlorophyll reduced biodiesel conformed to the standards of the USA, China and EU. Sodium copper chlorophyllin could be prepared from the bleaching effluent. The results presented herein offer a useful pathway to improve the quality of microalgae oil and reduce the cost of microalgae biodiesel.  相似文献   

17.
The oilseed crop Camelina sativa (camelina) has lower production costs than oilseed rape in some climates. For this reason, the production of biodiesel-grade methyl ester from camelina oil was evaluated. The evaluation included quality assessment of esters produced in laboratory and pilot plant, an examination of methods of improving ester low-temperature properties, and vehicle trials. Laboratory esterifications gave ester yields similar to rape-seed oil. Six 350 kg batches of unrefined camelina oil with acid values from 3 to 6 were esterified in a pilot plant. Ester-specific properties were satisfactory with one exception; the iodine number of 155 far exceeded the value of 120 required by the relevant EU standard. Fuel-specific properties of the camelina methyl esters were largely within specification, though low-temperature behaviour could be a problem in some climates. This problem could be overcome by the use of suitable pour-point depressants or by blending with diesel oil. In vehicle tests, the reduction in fuel economy with camelina ester was similar to that with biodiesel from other feedstocks. The high iodine number of camelina methyl ester did not lead to a more rapid deterioration of the lubricating oil. However, it was concluded that further engine trials would be needed before the use of camelina ester as an undiluted vehicle fuel could be recommended.  相似文献   

18.
This study analyses the variability of key yield components, the content of protein and crude fat in grain and the fatty acid composition of 50 spring accessions of Triticum monococcum, Triticum dicoccum and Triticum spelta of various origins. The average protein content of the grain of T. monococcum was 20.8%, of T. dicoccum 19.7%, and of spelt 17.0%. The crude fat content of T. monococcum grain (2.7%) was significantly higher compared with T. spelta (2.4%) and T. dicoccum (2.3%). In crude fat, fatty acids C18:2, C18:1 and C16 predominated. T. spelta was characterised by the highest concentrations of C18:2 and C16 (55.89% and 18.77% respectively), while T. monococcum had the highest content of C18:1 (26.35%). The structure of analysed fatty acids proved to be highly desirable in this species. A discriminant analysis performed separately for five variables: protein and fat content and three biometrical characters and separately for fatty acid composition enabled three Triticum species to be distinguished. These species also differed significantly with respect to the C18:1/C16 ratio which was equal to 1.78, 1.06, 1.47 and 0.99 in T. monococcum, T. dicoccum, T. spelta and Triticum aestivum respectively.  相似文献   

19.
20.
Biodiesel is a biodegradable, renewable, non-toxic and environmentally friendly alternative fuel. The cost of raw materials comprises 60-88% of the production cost in commercial biodiesel (fatty acid methyl esters, FAMEs) production. Therefore, the use of low-cost raw material as a substrate and an in situ process for biodiesel production are being preferred. In this case, rice bran, which contains 13.5% oil, was an interesting substrate. In situ esterification of high-acidity rice bran with methanol and sulfuric acid catalyst was investigated. The individual and interaction effects of methanol to rice bran ratio, sulfuric acid catalyst concentration and reaction time on purity and recovery of biodiesel were discussed. Our results suggest that under the following operation conditions: methanol to rice bran ratio of 5 mL/g, sulfuric acid concentration in methanol of 1.5 vol.%, and reaction time of 60 min, an in situ esterification operated on rice bran could yield FAMEs with a high purity and recovery. By applying an in situ esterification with n-hexane/water extractions, Indonesia will be succesfull in obtaining biodiesel from rice bran up to 96,000 ton per year.  相似文献   

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