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431.
Recently, there has been a growing interest in the recovery of agri-food waste within the circular economy perspective. In this study, the nutritional, phytochemical, and biological features of the cold-pressed hempseed oil (HSO) and hempseed meal (HSM) of two industrial hemp varieties (USO 31 and Futura 75, THC ≤ 0.2%) were evaluated. The HSOs showed a high total phenols and flavonoid content, which were confirmed by LC-DAD-ESI-MS analysis, with rutin as the most abundant compound (56.93–77.89 µg/100 FW). They also proved to be a rich source of tocopherols (81.69–101.45 mg/100 g FW) and of a well-balanced ω-6 to ω-3 fatty acid ratio (3:1) with USO 31, which showed the best phytochemical profile and consequently the best antioxidant activity (about two times higher than Futura 75). The HSMs still retained part of the phytochemicals identified in the HSOs (polyphenols, tocopherols, and the preserved ω-6/ω-3 fatty acids ratio) and a modest antioxidant activity. Furthermore, they showed a very interesting nutritional profile, which was very rich in proteins (29.88–31.44 g/100 g FW), crude fibers (18.39–19.67 g/100 g), and essential and non-essential amino acids. Finally, only a restrained amount of anti-nutritional factors (trypsin inhibitors, phytic acid, and condensed tannins) was found, suggesting a promising re-use of these byproducts in the nutraceutical field.  相似文献   
432.
The study of animal mummification in ancient Egypt has recently received increasing attention from a number of modern scholars given the fact that this part of ancient Egyptian funerary and religious history is a practice yet to be fully understood. In this study, nine samples of embalming matter were extracted from six gazelle mummies from the archaeological site of Kom Mereh (modern village of Komir), dated to the Roman period of dominance in ancient Egypt. All samples were analyzed for the presence of inorganic and organic matter applying a multi-analytical approach based on Fourier transform infrared spectroscopy (FT-IR) and gas chromatography–mass spectrometry (GC-MS). Furthermore, in order to identify more specific compounds such as bitumen and beeswax in studied balms, each sample was subjected to a solid phase extraction (SPE) and saponification separation process, respectively. The results of this study revealed that the majority of the analyzed embalming substances sampled from six gazelle mummies from Kom Mereh were complex mixtures of plant oils, animal fats, conifer resin, and beeswax. In this regard, this study was able to report a practice until now unmentioned in the scientific literature, namely, the use of cruciferous oil, derived from seeds of Brassicaceae plants, in animal mummification.  相似文献   
433.
采用索氏提取法提取油松籽中的油脂,得油率为42.9%;对油脂进行甲酯化处理后用气相色谱-质谱联用仪检测其中的脂肪酸组成及含量。实验结果表明,油松籽油中含有7种脂肪酸,分别为肉豆蔻酸10.38%、硬脂酸3.05%、油酸21.98%、亚油酸(13,16-十八碳二烯酸)3.53%、亚油酸(9,12-十八碳二烯酸)38.38%、亚麻酸20.06%和二十碳三烯酸2.62%,其中饱和脂肪酸含量为13%,不饱和脂肪酸含量为87%。  相似文献   
434.
硝酸镧对水稻老化种子活力影响的作用机制   总被引:15,自引:2,他引:13  
自然和人工老化的水稻种子经La(NO  相似文献   
435.
We confined the formation and characterization of heterogenous nano-catalysts and then used them to produce biodiesel from the novel non-edible seed oil of Prunus aitchisonii. P. aitchisonii seeds’ oil content was extracted at about 52.4 ± 3% with 0.77% FFA. Three different heterogenous nano-catalysts—calcined (CPC), KPC, and KOH-activated P. aitchisonii cake Titanium Dioxide (TiO2)—were synthesized using calcination and precipitation methods. The mentioned catalysts were characterized through XRD, SEM, and EDX to inspect their crystallin dimension, shape, and arrangement. Titanium dioxide has morphological dimensions so that the average particle size ranges from 49–60 nm. The result shows that the crystal structure of TiO2 is tetragonal (Anatase). The surface morphology of CPC illustrated that the roughness of the surface was increased after calcination, many macropores and hollow cavities appeared, and the external structure became very porous. These changes in morphology may increase the catalytic efficiency of CPC than non-calcined Prunus aitchisonii oil cake. The fuel belonging to PAOB stood according to the series suggested by ASTM criteria. All the characterization reports that P. aitchisonii is a novel and efficient potential source of biodiesel as a green energy source.  相似文献   
436.
芹菜籽香气成分研究   总被引:8,自引:0,他引:8  
采用固相微萃取法萃取黑龙江产芹菜籽香气成分,然后用GC—MS进行成分分析,并与水蒸气蒸馏法获得的精油成分进行比较.用CAR on PDMS萃取柱进行顶空固相微萃取时,共检测出26种成分,鉴定出占总成份89.650%的20种成分,主要成分为柠檬烯(35.980%),β-月桂烯(20.500%),β-蛇床烯(16.160%),正戊基苯(5.295%),β-蒎烯(3.412%),α-蛇床烯(3.293%).水蒸汽蒸馏法提取芹菜籽,以1.18%产率获得精油,共检测出23个成分,鉴定出占总精油91.375%的18种成分,主要成分为柠檬烯(31.149%),β-蛇床烯(22.281%),对甲苯基异戊酸酯(14.944%),α-2-丙烯基苯甲醇(9.872%),β-月桂烯(4.324%)和α-蛇床烯(4.322%).  相似文献   
437.
Abelmoschus manihot (L.) Medic (AM), called Huangshukui in Chinese, is a widely used medicinal plant. Each part of AM has medicinal value, including Abelmoschi Radix (AR), Abelmoschi Herba (AH), Abelmoschi Folium (AF), Abelmoschi Corolla (AC), and Abelmoschi Semen (AS). However, only AC is documented in the Chinese Pharmacopoeia. In order to investigate whether there is any difference between AC and the other parts of AM, an analytical method based on ultra-fast performance liquid chromatography coupled with triple quadrupole-linear ion trap mass spectrometry (UFLC-QTRAP-MS/MS) was established for the simultaneous determination of 35 constituents in different parts of AM. Moreover, principal components analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were applied to classify and evaluate the different parts of AM based on the content of the 35 constituents. The total contents of the 35 constituents in AC were significantly higher than in the other parts of AM and the results revealed significant differences between AC and the other parts of AM. Eight constituents were remarkably related to the sample classifications. This research does not just provide the basic information for revealing the distribution patterns in different parts of AM from the same origin, but also complements some of the scientific data for the comprehensive quality evaluation of AC.  相似文献   
438.
运用固相萃取和高效液相色谱技术,建立炒货食品及坚果制品中丁基羟基茴香醚(BHA)、二丁基羟基甲苯(BHT)、叔丁基对苯二酚(TBHQ)、没食子酸丙酯(PG)等人工合成的抗氧化剂和茶多酚、甘草抗氧化物、迷迭香提取物等天然抗氧化剂的测定方法。样品经甲醇、异丙醇、乙腈等混合溶剂提取,冷冻离心后经C18柱固相萃取净化,用高效液相色谱检测。各抗氧化剂残留量在6~100 mg/L范围内呈良好线性关系,加标回收率为80%~106%。  相似文献   
439.
In the present study analyses concerning the composition of vitamin E, sterols, triglycerides, and fatty acids of three Teucrium species (Teucrium alopecurus, T. nabli, and T. polium) seed oil were performed. Linoleic, linolenic, and palmitic were the major fatty acids. The oil was characterized by a high amount of phytosterol, wherein clerosterol, sitosterol, and stigmasterol are the main constituents. The amount of tocopherol is nearly 550 mg/kg of oil, with α-tocopherol as the major isomer. Information concerning the composition of Teucrium seed oil is very important for evaluating the therapeutic effect of this oil. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 261–264, May–June, 2009.  相似文献   
440.
After chemical mechanical planarization (CMP), the reason which caused the formation of Cu-oxide defects at the interface between Cu deposit and TaN barrier layer has been studied. The experimental results of atomic force microscopy, secondary ion mass spectroscopy, X-ray diffraction demonstrated that the agglomeration phenomenon was found on Cu seed in the thickness of only 10 nm, thus resulting in the electrodeposited Cu film with more abundant C impurities at Cu/TaN interface and lower (1 1 1)/(2 0 0) ratio compared to the thick one (30 nm). Therefore it caused the Cu deposit with poor corrosion resistance and then the Cu-oxide defects were easily formed after CMP. As a result, the correlation between Cu-oxide defects at the Cu/TaN interface and the agglomeration on Cu seed layer was proposed herein.  相似文献   
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