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1.
The chemical composition, main physicochemical properties and thermal stability of oil extracted from Acacia senegal seeds were evaluated. The oil, moisture and the ash contents of the seeds were 9.80%, 6.92% and 3.82%, respectively. Physicochemical properties of the oil were iodine value, 106.56 g/100 g of oil; saponification value, 190.23 mg KOH/g of oil; refractive index (25 °C), 1.471; unsaponifiable matter, 0.93%; acidity, 6.41% and peroxide value, 5.43 meq. O2/kg of oil. The main fatty acids in the oil were oleic acid (43.62%) followed by linoleic acid (30.66%) and palmitic acid (11.04%). The triacylglycerols (TAGs) with equivalent carbon number ECN 44 (34.90%) were dominant, followed by TAGs ECN 46 (28.19%), TAGs ECN 42 (16.48%) and TAGs ECN 48 (11.23%). The thermal stability analysed in a normal oxidizing atmosphere showed that the oil decomposition began at 268.6 °C and ended at 618.5 °C, with two stages of decomposition at 401.5 °C and 576.3 °C. According to these results, A. senegal seed oil has physicochemical properties, fatty acids composition and thermal characteristics that may become interesting for specific applications in several segments of food and non-food industries.  相似文献   

2.
Serum and liver lipids of rats fed rubber seed oil   总被引:1,自引:0,他引:1  
Crude rubber seed oil (RSO) was incorporated at the 5% level in diets free of cholesterol or containing 1% cholesterol, respectively. These studies were initiated for the purpose of evaluating the palatability and potential toxicity of RSO. Corn oil was used as a control. A considerable amount of unsaponifiable matter was detected in RSO. In addition, RSO was found to possess a fatty acid profile which was fairly different from that of corn oil, primarily due to a much higher content of linolenic acid and a lower content of linoleic acid in RSO. No adverse effects on food intake and average daily gain were observed in rats fed RSO in both cholesterol-free and cholesterol diets. The presence of RSO in cholesterol-free diets results in lower (p<0.05) serum and liver total cholesterol levels than in control animals. A relative hypercholesterolemic effect compared to corn oil was observed however, when RSO was added to diets containing 1% cholesterol. In summary, the physicochemical properties of RSO as well as the presence of cholesterol in the diet are important factors in evaluating the cholesterolemic effect of RSO.  相似文献   

3.
糯玉米营养品质和风味品质的鉴定分析   总被引:3,自引:0,他引:3  
本试验是以糯玉米、普通玉米、甜玉米为材料,研究其口感品质与营养品质及风味品质的相关性。通过三种玉米口感品质、营养品质、风味品质的鉴定及研究分析,研究结果表明,感官品尝是研究糯玉米综合品质的有效手段;糯玉米各类营养物质含量较高且均衡,较好地解决了甜、糯、韧、滑的口感问题;胚乳中的含糖量和支链淀粉含量与口感有密切关系;糯玉米风味品质以脂香和蜡香为主,主要成分包括棕榈酸、亚油酸、正十六羧酸乙酯等。  相似文献   

4.
The potential of near-infrared reflectance spectroscopy (NIRS) to estimate the oil content, fatty acid composition, and protein content of Jatropha curcas seeds was studied. Seventy-four intact kernels from various sources were scanned by NIRS. All samples were analyzed for oil content (hexane extractions), fatty acid composition (gas chromatography), and protein content (Kjeldahl). Calibration equations were developed for oil content, individual fatty acids (oleic C18:1, linoleic C18:2, stearic C18:0 and palmitic C16:0), and protein content. The performance of the calibration equations was evaluated through external and cross-validation. The results showed that NIRS was a reliable, accurate and nondestructive technique to estimate oil and protein contents, as well as oleic and linoleic fatty acid concentrations in J. curcas kernels; NIRS provides a rapid, simple, and cost-effective alternative method for screening intact J. curcas kernels.  相似文献   

5.
The unsaponifiable lipid fraction of plant-based foods is a potential source of bioactive components such as phytosterols, squalene, and tocopherols. The objective of the present study was to determine the levels of phytosterols, and squalene, as well as tocopherols (α and β + γ) in selected grains, seeds, and legumes. The method comprised acid hydrolysis and lipid extraction followed by alkaline saponification, prior to analysis by HPLC. In addition, the fatty acid profile of the foods was determined via total lipid extraction, fatty acid derivitisation and GC analysis. In general, β-sitosterol was the most prevalent phytosterol, ranging in concentration from 24.9 mg/100 g in pumpkin seed to 191.4 mg/100 g in peas. Squalene identified in all foods examined in this study, was particularly abundant in pumpkin seed (89.0 mg/100 g). The sum of α- and β+ γ-tocopherols ranged from 0.1 mg/100 g in rye to 15.9 mg/100 g in pumpkin seeds. Total oil content ranged from 0.9% (w/w) in butter beans to 42.3% (w/w) in pumpkin seed and the type of fat, in all foods examined, was predominantly unsaturated. In conclusion, seeds, grains, and legumes are a rich natural source of phytosterols. Additionally, they contain noticeable amounts of squalene and tocopherols, and in general, their fatty acid profile is favorable.  相似文献   

6.
Awara (Astrocaryum vulgare M.) pulp oil has been shown to possess anti-inflammatory properties in vivo, and contains an unsaponifiable matter rich in bioactive compounds. This study focused on the ethanolic unsaponifiable fraction (EUF) of awara pulp oil. Its chemical composition has been characterized: carotenoid, phytosterol, and tocopherol contents represent 125.7, 152.6, and 6.8?μg/mg of EUF, respectively. We further evaluated this fraction for anti-inflammatory properties in J774 macrophages activated by lipopolysaccharide (LPS) plus interferon (IFN) γ to understand the biological effects of awara pulp oil. EUF strongly decreased nitric oxide (NO), prostaglandin E2, tumour necrosis factor (TNF) α, and interleukin (IL) -6 and -10 production in activated J774 cells. Moreover, it inhibited expression of inducible NO synthase and cyclooxygenases-2 in vitro. The anti-inflammatory properties of EUF were also confirmed in vivo by modulation of TNFα, IL-6 and IL-10 serum concentration in an endotoxic shock model. Pre-treatment with awara oil fraction offers promise as a protective means to lower the production of excessive amounts of pro-inflammatory molecules.  相似文献   

7.
The fish lipid was extracted from the body muscle (edible portion) of fresh Lepidocephalus guntea (Ham.) fish and the lipid content of the fish in size-1 (below 8.5 cm), size-2 (8.5-9.5 cm) and size-3 (above 9.5 cm) were found to be 2.515, 3.013 and 3.455%, respectively. The specific gravity and refractive index of the lipid were found to be 0.93 at 30 degrees C and 1.467 at 31.5 degrees C, respectively. The saponification value, saponification equivalent, iodine value, peroxide value and acetyl value of the lipid were found to be 220.325, 254.624, 96.05, 1.993 and 11.32, respectively. The acid value, percentage of free fatty acid as oleic and unsaponifiable matter present in the lipid were found to be 2.005, 1.008 and 0.593, respectively. The fatty acid composition of the lipid was determined qualitatively and quantitatively by TLC and GLC. The analysis revealed that the fatty acid composition of the lipid lies between C14 to C20. The fish lipid of Lepidocephalus guntea (Ham.) was found to contain (average value) myristic acid (3.17%), palmitoleic acid (7.45%), palmitic acid (29.16%), linolenic acid (7.13%), linoleic acid (5.57%), oleic acid (22.93%), stearic acid (17.42%), arachidonic acid (7.17%) and arachidic acid in trace amount.  相似文献   

8.
Cryptostegia grandiflora, a member of Asclepiadaceae, was evaluated as a potential multi-use crop. The plant contained 14.0% protein, 6.5% oil, 6.9% polyphenol, and 2.13% hydrocarbon. The gross heat value of the species was 3878.0 cal/g, while the oil fraction was 7350.1 cal/g, and the hydrocarbon fraction was 9300.0 cal/g. The NMR spectra of the hydrocarbon fraction reveals the presence of cis-polyisoprene (natural rubber). The oil fraction contains both saturated and unsaturated fatty acids including: lauric acid (trace), myristic acid (15.24%), palmitic acid (25.90%), stearic acid (3.8%), oleic acid (8.0%), linoleic acid (24.76%), and arachidic acid (22.28%). The high proportion of saturated fatty acids and the high oil content (>5.0%) make C. grandiflora a potential source for industrial raw material and alternative for conventional oil.  相似文献   

9.
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   

10.
The utilization of Hura crepitans seed oil in the formulation of alkyd resins was investigated using a two-stage alcoholysis-polyesterification method. The percentage yield of the oil was 36.4%; and the physicochemical characterization revealed that the seed oil is an unsaturated semi-drying oil. The fatty acid profile of the oil showed that it contains linoleic acid (81.6%) as the most abundant fatty acid, and two other fatty acids: palmitic acid (16.92%) and stearic acid (1.76%). Short (I), medium (II) and long (III) oil alkyds were synthesized using the oil, glycerol and phthalic anhydride in different ratios. Properties of the three prepared samples of H. crepitans seed oil alkyds having oil content of 30% (I), 50% (II), and 65% (III) were evaluated. The alkyd resins synthesized compared favourably with the commercially available alkyd resin. The presence of unsaturation in the oil was confirmed by infra-red peak at 2930 cm−1 attributed to CC stretch. The infra-red peaks of the sample also compared well with that of the commercial sample indicating that H. crepitans seed oil has been successfully converted to alkyd resin. Evaluation of prepared alkyds by determination of acid values, solubility in butanol and toluene, resistance of dry film to acid, alkali and water, and drying time revealed that H. crepitans seed oil is a potential raw material for the coating industry.  相似文献   

11.
The effect of stage of maturity on total lipids, fatty acids, yields and essential oil composition and their antimicrobial and free radical scavenging activities of the Schinus molle fruits was investigated. The content of total lipids varied from 2.87 to 5.35% (w/w, dw) and were rich in unsaturated fatty acids particularly linoleic acid. As maturation progress, the essential oil yield dropped from 5.18% to 1.15%. Monoterpene hydrocarbons with α-phellandrene (35.15-40.38%), limonene + β-phellandrene (21.47-36.62%), β-myrcene (7.61-24.96%) and α-pinene (1.92-2.58%) were found to be the main components. At the same time, the essential oils were evaluated for their antimicrobial and free radical scavenging activities. They were found to be active against Bacillus subtilis, Bacillus cereus, Salmonella typhymurium and Escherichia coli but they do not inhibit the growth of Candida albicans. Conversely, they showed very weak activity against the DPPH radical. In both assay, the oil derived from the intermediate stage was reported as more efficient.  相似文献   

12.
Dry common beans (Phaseolus vulgaris L.) were evaluated for potential conversion of starch to ethanol. Eight varieties of beans with average starch content of 46% (db) were assayed in a laboratory-scaled process based upon the commercial corn dry grind fermentation process. Ethanol yield was 0.43-0.51 g ethanol/g glucose (0.19-0.23 g ethanol/g beans). The average ethanol yield for the eight bean types was 92% of maximum theoretical yield, demonstrating that starch from beans could be efficiently converted to ethanol. Ethanol concentration obtained from 20% (w/w) solids loading was 3.5-4.4% (w/v). The residual fermentation solids contained, on a dry basis, 37.1-43.6% crude protein, 10.8-15.1% acid detergent fiber and 19.1-31.3% neutral detergent fiber.  相似文献   

13.
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   

14.
Chia (Salvia hispanica L.), an annual herb of the Labiatae family, produces seeds which were one of the basic foods of Central American civilizations in pre-Columbian times. Chia seed contains the highest known percentage of α-linolenic fatty acid of any plant source. In recent years, chia seed has become increasingly important for human health and nutrition because of its high content of α-linolenic fatty acid, and the beneficial health effects that arise from its consumption. A study was undertaken to characterize protein and oil contents as well as fatty acid composition of chia seeds grown in some larger commercial fields, in an attempt to determine how these components are affected by location. Oil saturation tended to decrease as elevation of seed production increased, with decreasing levels of palmitic, stearic, oleic, and linoleic fatty acids found. The main constituent in the chia oil was ω-3 α-linolenic fatty acid, and ranged from 64.8% to 56.9%. Differences were significant (P < 0.05) among locations. Significant differences in protein content and fatty acid composition were also found for the commercially grown chia originating from three ecosystems. It is possible that these differences could be used to distinguish chia's origin, if additional research was undertaken to characterize such differences.  相似文献   

15.
The physicochemical characteristics, fatty acid and triacylglycerol compositions, DSC profile and UV/vis spectrum of oil extracted from Albizia julibrissin seeds were determined in this study. The oil content and the moisture of the seeds were 10.50% and 1.56%. The free fatty acid, the peroxide value, the p-anisidine value, the saponification value, the iodine value were 2.54%, 6.61 mequiv. O2/kg of oil, 1.98, 190.63 (mg KOH/g) and 111.33 (g/100 g of oil), respectively. The specific extinction coefficients K232, K268 were 7.55 and 0.96, respectively. Linoleic acid (C18:2, 58.58%), palmitic acid (C16, 13.86%) and oleic acid (C18:1, 10.47%) were the dominant fatty acids in the A. julibrissin seed oil. LLL (36.87%), OLL (21.62%), PLL (16.69%) and PLO + SLL (8.59%) were the abundant triacylglycerol representing > 83% of the seed oil (L: linoleic, O: oleic, P: palmitic, S: stearic). The DSC melting curves reveal that: melting point = −14.70° C and melting enthalpy = 54.34 J/g. A. julibrissin seed oil showed some absorbance in the UV-B and UV-C ranges. The results of the present analytical study show that A. julibrissin is a promising oilseed crop, which can be used for making soap, hair shampoo and UV protectors. Furthermore, the high level of unsaturated fatty acids makes it desirable in terms of nutrition.  相似文献   

16.
This study is designed to examine the yield components, fatty acid, and essential oil compositions and phenolic contents fruit essential oil composition, the total phenolic amounts as well as the antioxidant activities of cumin (Cuminum cyminum L.) seeds under drought. This plant is one of the most common aromatics in the Mediterranean kitchen. Plants were treated with different levels of water deficit: control (C), moderate water deficit (MWD) and severe water deficit (SWD). Our results indicated that MWD improved the number of umbels per plant as well as the number of umbellets per umbel and the seed yield, in comparison to the control, but it decreased under SWD. Fatty acid composition analysis indicated that petroselinic acid was the major fatty acid (55.9%) followed by palmitic (23.82%) and linoleic (12.40%) acids. Water deficit enhanced the palmitic acid percentage and affected the double bound index of the fatty acid pool and thus the oil quality. The essential oil yield was 1.64% based on the dry weight and increased by 1.40 folds under MWD. Nevertheless it decreased by 37.19% under SWD in comparison to the non treated seeds. Drought results on the modification of the essential oil chemotype from γ-terpinene/phenyl-1,2 ethanediol in the control seeds to γ-terpinene/cuminaldehyde in stressed ones. Besides, total phenolic contents were higher in the treated seeds (MWD and SWD). Results suggest that water deficit treatment may regulate the production of bioactive compounds in cumin seeds, influencing their nutritional and industrial values. Besides, antioxidant activities of the extracts were determined by four different test systems, namely DPPH, β-carotene/linoleic acid chelating and reducing power assays and showed that treated seeds (MWD and SWD) exhibited the highest activity.  相似文献   

17.
Seeds of sixty four genotypes ofBrassica campestris L. (Toria) were analyzed for oil content and fatty acid composition. Oil content varied from 38.9% to 44.6%. Major fatty acids viz. oleic, linoleic, linolenic, eicosenoic and erucic acids exhibited ranges from 10.1% to 17.3%, 5.9% to 14.5%, 5.2% to 15.0%, 7.7% to 13.7% and 39.6% to 59.9%, respectively. Compared to the standard cultivar ITSA, four genotypes contained 5 to 8% lower content of erucic acid; and six genotypes contained significantly higher content of linoleic acid. Oil was positively correlated with erucic acid. The observed inverse relationship between linoleic and erucic acid contents might be utilized in breeding nutritionally better Toria cultivars with both high linoleic and low erucic acid contents.  相似文献   

18.
Crude vegetable oil obtained by solvent extraction from rubber seed (Hevea brasiliensis) and breadfruit (Artocarpus altilis) were subjected to alkali refining (neutralisation), degumming and bleaching. At each stage of refining, the crude and the refined oil were analysed for their physical and chemical characteristics notably specific gravity, moisture and volatile matter content, saponification, iodine values, peroxide value, unsaponifiable matter, fatty acids and free fatty acids. Results showed an improvement in the quality of the oil after refining. Refining decreased the free fatty acids and peroxide value, which are some of the characteristics that determine stability. There was a very slight decrease in saponification value and unsaponifiables matter after refining. Refining did not have much effect on the fatty acid composition except slight nonconsistent decreases in saturated and unsaturated fatty acids. There was no decrease in iodine value.  相似文献   

19.
Kenaf (Hibiscus cannabinus L.) is a fibre plant native to east-central Africa. The potential for using kenaf seeds as a source of edible oil is often overlooked when considering kenaf as a fibre and feed crop. The aim of this research was to study and compare the fatty acid composition and oil content of eight commercial kenaf varieties from various countries. Linoleic, oleic, and palmitic acid were the predominant fatty acids in all cultivars. Percentages of fatty acids varied greatly among different kenaf varieties. Gregg had the highest percentage of linoleic acid whilst El Salvador had the lowest. El Salvador had the highest percentage of oleic acid and Endora had the highest percentage of palmitic acid. Stearic acid and palmitic acid were positively correlated, as well as stearic and linoleic acid. Increasing stearic and linolenic acid and reducing palmitic acid at the same time therefore might be difficult through conventional breeding. The oil content was 19.84% on average and there was not much difference between the varieties. The relatively high oil content and the unique fatty acid composition, suggested that kenaf seed could be used as a source of edible oil. Kenaf oil can be considered nutritionally healthy because of the relatively high amount of monounsaturated and polyunsaturated fatty acids.  相似文献   

20.
The purpose of the study was to determine the lipid composition of potatoes during sprouting. Sprouts from Pontiac and Katahdin potatoes as well as two clones (the genetic material from crosses of a population ofSolanum andigenum from South America andSolanum tuberosum from North America) were found to be significantly higher in crude lipid than either the cortex or pith sections of the tuber. The cortex section was found to be higher in lipid than the pith section. Crude lipid was fractionated into phospholipid, neutral fat, and free fatty acids, and for each of the sections of potatoes the highest percentage of lipid was found in the phospholipid fraction. The fatty acid found in highest concentration in the phospholipid fraction was linoleic acid, but considerable quantities of linolenic and palmitic acids were also present. Synthesis of phospholipid occurs in the actively growing sprout, and compounds that interfere with lipid synthesis, particularly phospholipid synthesis, should prove to be effective sprout inhibitors.  相似文献   

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