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1.
Moromi (the fermented mash) of “mugi shochu” that had been artificially contaminated with pesticides was distilled to elucidate the fate of pesticides in the distillation process. The pesticides residing in the distillate were quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Of the analyzed pesticides (249 compounds), 89% were not detected in the distillate, showing that the distillation process minimized the risk of pesticide contamination.  相似文献   

2.
A biosurfactant-producing and hydrocarbon-utilizing bacterium, Pseudomonas aeruginosa USM-AR2, was used to assist conventional distillation. Batch cultivation in a bioreactor gave a biomass of 9.4 g L(-1) and rhamnolipid concentration of 2.4 g L(-1) achieved after 72 h. Biosurfactant activity (rhamnolipid) was detected by the orcinol assay, emulsification index and drop collapse test. Pretreatment of crude oil TK-1 and AG-2 with a culture of P. aeruginosa USM-AR2 that contains rhamnolipid was proven to facilitate the distillation process by reducing the duration without reducing the quality of petroleum distillate. It showed a potential in reducing the duration of the distillation process, with at least 2- to 3-fold decreases in distillation time. This is supported by GC-MS analysis of the distillate where there was no difference between compounds detected in distillate obtained from treated or untreated crude oil. Calorimetric tests showed the calorie value of the distillate remained the same with or without treatment. These two factors confirmed that the quality of the distillate was not compromised and the incubation process by the microbial culture did not over-degrade the oil. The rhamnolipid produced by this culture was the main factor that enhanced the distillation performance, which is related to the emulsification of hydrocarbon chains in the crude oil. This biotreatment may play an important role to improve the existing conventional refinery and distillation process. Reducing the distillation times by pretreating the crude oil with a natural biosynthetic product translates to energy and cost savings in producing petroleum products.  相似文献   

3.
以富含精油而著称的唇形科植物木香薷(Elsholtzia stauntoni Benth.)为研究试材,采用水蒸气蒸馏法设计不同的试验处理条件,对木香薷不同部位的精油进行提取,研究其最佳提取工艺。结果表明:木香薷精油提取的最佳工艺为切段后水蒸气蒸馏法,馏出液体积为1 500 mL;水蒸气蒸馏法提取精油要优于共沸蒸馏法。在对木香薷不同部位精油提取的比较研究中,以花穗组材料提取的精油量最大,花穗组与茎叶组间提取的精油量无显著差异,光茎组提取的精油量最少。  相似文献   

4.
3‐Hydroxypropionaldehyde (3‐HPA), which can be derived from biomass, is an important precursor for low‐cost, large‐volume acrolein‐based chemicals like acrylic acid and acrylamide with a wide range of applications. In order to find an efficient process for isolating 3‐HPA from fermentation broth, we comparatively investigated several separation methods including precipitation with hydrazides, immobilization with amines, reactive extraction with thiols, extraction with hydrophilic solvents, and reactive distillation as acrolein. It turned out that the reactive distillation is the most efficient method for in situ recovery of 3‐HPA as acrolein. In a reactive distillation process at 37°C and Hammett acidity H0 = –1, the aldehyde concentration was reduced to 6 ± 1 mM in the transformation medium and increased to 1866 ± 146 mM in the distillate. The yield was 96 ± 8%. These experimental results are close to the calculated ideal equilibrium results assuming total dehydration of 3‐HPA to acrolein. The main advantages of the reactive distillation process are that the recovery, purification, and concentration of acrolein are carried out in one step and the process is well suited for large‐scale production at low costs.  相似文献   

5.
用于高粘度易焦化基质高沸点蒸馏的新技术   总被引:2,自引:0,他引:2  
进行高粘度易焦化有机基质高沸点蒸馏的最大难题,是高沸点气化物质被高粘度有机基质包裹难以气化,大大影响收率,并且结成坚硬的焦垢后无法清洗,导致无法连续生产。针对发酵法生产甘油(丙三醇)提取中的这一难题,发明了相应的载体蒸馏技术,在大生产应用中获得满意的结果。蒸馏收率大于90%,蒸馏残渣清洗容易,可连续生产。  相似文献   

6.
林业有害植物豚草挥发油GC-MS成分分析   总被引:1,自引:0,他引:1  
通过对豚草新鲜枝叶进行水蒸气蒸馏,应用色质分析(GC-MS)方法,对林业有害植物豚草挥发成份进行鉴定及定量分析,鉴定出28种化合物,为探讨豚草能分布于不同的水分和热量带并使其他植物受害的机制提供了依据。  相似文献   

7.
We investigated the enantiomeric enrichment of enantiomeric mixtures of alpha-phenylethylamine by achiral dicarboxylic acids. As achiral agents oxalic, malonic, fumaric, and phthalic acids were used. The results of the enantiomeric enrichment via partial salt formation followed by distillation were compared with enantiomer separation via crystallization of the neutral salt. Without the presence of a solid phase, enantiomeric separation is impossible. Our results show that the properties of the solid phase determine the separation. It is also confirmed by our observation that the eutectic points, which are observed on the 3-phase solubility diagrams of the solid neutral salts, can be found at the same initial enantiomeric composition as the point of intersection of distillate and residue of the distillation curves and the point of intersection of precipitated salt and mother liquor of the crystallization curves. Copyright 2000 Wiley-Liss, Inc.  相似文献   

8.
Chiba seed (Psoralea corylifolia L.) oil, which contains bioactive components such as bakuchiol, psoralen, and isosporalen, is recognized for its high medicinal value and is widely used in Chinese and Indian Ayurvedic medicinal systems. Several earlier studies have proved the antibacterial and antioxidant properties of the key components in the seed oil. In view of the importance of the bioactive components in the global market, this study was carried out to separate the key components by supercritical carbon dioxide extraction and further enrichment by the molecular distillation technique. The effects of the process variables such as pressure (400∼2,000 μm), temperature (140∼200°C), and wiper speed (120∼200 rpm) were studied based on response surface methodology. The predicted model was maximized for the bakuchiol content in the distillate. And a predicted maximum of 72% bakuchiol content was confirmed by the experiment under the optimized process conditions.  相似文献   

9.
Guinea pigs received skin application of petroleum-derived mineral oil distillate, containing about 10% of polycyclic aromatic hydrocarbons with the 4 hours exposure time everyday during 20 days. 100% distillate preparation and it's 50%, 3% or 0.5% solutions in furfurol and ethanol are used. It resulted in the distillate-dose-dependent cytochrome P-450 induction (1.38-2.23-fold) in liver of the all exposed groups of guinea pigs and in 20-60% decrease in microsomal and cytosol glutathione transferase activities in groups which received 50% and 3% mineral oil distillate solutions. Ratio values of cytochrome P-450 content level to glutathiontransferase activity level depended linearly on the distillate doses, and it increased 2.7-4.4-fold with the distillate concentration increasing in the preparation from 0.5% to 50%. Conclusion was made that with increasing distillate doses the process of polycyclic aromatic hydrocarbon activation with the genotoxic metabolite formation predominated over the process of those metabolite detoxication.  相似文献   

10.
The ginger extract obtained with supercritical CO2 fluid was purified by molecular distillation (MD), and the chemical compositions, antioxidant and cytotoxic activities of ginger extract and its distillates were investigated. Analysis revealed that the ginger extract was rich in terpene hydrocarbons, along with oxygenated terpenes and other non‐volatile compounds. The MD distillates were prepared in a series of stages and the active compounds like terpenes and gingerols could be separated by MD. The major compounds of the distillates purified by MD at 40 °C, 80 Pa and 60 °C, 80 Pa were terpene hydrocarbons. Additional distillates obtained by MD at 80 °C, 80 Pa and 100 °C, 60 Pa were predominated by terpene hydrocarbons and oxygenated terpenes. Until the operating conditions of MD reached 150 °C and 2 Pa, some non‐volatile compounds were concentrated in the final distillate. Moreover, antioxidant activities and the cytotoxic effects on three human cancer cells in final MD distillate were superior to other extracts, and this phenomenon could be mainly supported by the phenols. The MD could be used to prepare ginger distillates with better antioxidant and cytotoxic activities.  相似文献   

11.
The essential oil of Artemisia monosperma obtained by steam distillation of the aerial parts of the plant was shown to have insecticidal activity against house fly, cotton leaf worm and the rice weevil. The chemical structure of the active ingredient from the steam distillate was shown to be 3-methyl, 3-phenyl-1,4-pentadiyne.  相似文献   

12.
A new method is described for the enrichment of enantiomeric mixtures having an enantiomeric ratio other than 1:1. The method is based on partial salt formation of the enantiomeric mixture with an achiral substance followed by the distillation of the free enantiomer. The distillate has a different enantiomeric composition than the starting mixture. The method was performed on enantiomeric mixtures of α-phenylethylamine using four different dicarboxilic acids. © 1995 Wiley-Liss, Inc.  相似文献   

13.
Hydrocracking of the oils of Botryococcus braunii to transport fuels   总被引:1,自引:0,他引:1  
Hydrocarbon oils of the alga Botryococcus braunii, extracted from a natural "bloom" of the plant, have been hydrocracked to produce a distillate comprising 67% gasoline fraction, 15% aviation turbine fuel fraction, 15% diesel fuel fraction, and 3% residual oil. The distillate was examined by a number of standard petroleum industry test methods. This preliminary investigation indicates that the oils of B. braunii are suitable as a feedstock material for hydrocracking to transport fuels.  相似文献   

14.
Abstract:  The leaf extracts of Populus nigra were collected and identified by steam distillation, air entrainment and gas chromatographic–mass spectrometric analysis. Electroantennograms were recorded from Helicoverpa armigera adults in response to the chemicals identified. Both aromatic compounds and green-leaf volatiles elicited strong responses. Field experiments revealed that the active compounds responsible for attracting H. armigera moths are mainly short-side-chain aromatic alcohols and aldehydes. We, for the first time, used agaropectin as the controlled-release matrix of insect attractants. A five-component lure containing all the aromatics without phenolics, mixed in the proportions as found in the steam distillate of the leaves collected in August, produced the best trap catch. The results showed that the volatiles of wilted leaves of P. nigra can attract H. armigera adults by feeding attraction.  相似文献   

15.
Creosote, a coal-tar distillation product, contains mutagens which are volatile at 37 degrees C. After distillation of creosote we found that these volatile mutagens were present in the distillation fraction with the highest boiling range (greater than 360 degrees C). The "volatile mutagenic activity" was connected with the presence of fluoranthene, a polycyclic aromatic hydrocarbon. Commercially available fluoranthene was positive in the so-called "taped-plate assay" (the test system used for the detection of volatile mutagens) towards the strains TA98 and TA100 in the presence of S9 mix. The tested creosote and coal tar contained fluoranthene in concentrations of 5.2 and 2.2%, respectively.  相似文献   

16.
The zinc dust distillates of rubrofusarin, nor-rubrofusarin, and methylxanthones (1-, 2-, 3-, and 4-methylxanthones and l-methyl-3,6,8-trihydroxyxanthone) have been investigated.

On zinc dust distillation, rubrofusarin and nor-rubrofusarin afforded naphthalene and anthracene in low yield, but did not give methylxanthene expected from the formerly proposed structure of methylxanthone.

Methylxanthones are considered to give the corresponding methylxanthenes in the distillates; and it is true for 2-, 3-, and 4-methylxanthones. However, in the 1-methyl derivatives the main product was not 1-methylxanthene but anthracene. It has been found also that on that condition all methylxanthones examined did not give naphthalene that was a main zinc dust distillate in rubrofusarin.

Thus, we conclude that it is appropriate to assign the structure of naphthalene derivative for rubrofusarin instead of the so far proposed methylxanthone structure.  相似文献   

17.
The amounts of isobutyl and isoamyl alcohol which are the main constituents of fusel oil are determined fractionally. Isobutyl and isoamyl alcohol give different colors by treatment with p-dimethylaminobenzaldehyde in sulfuric acid. Using this color difference the amount of each of these alcohols in fusel oil is determined colorimetrically. These alcohols arise during alcoholic fermentation and are concentrated in the distillate by distillation, and affect the flavor of distilled spirits, such as brandy and whisky, i.e., butyl alcohol is buttery and amyl alcohol is aromatic. So determination of the amounts of these alcohols fractionally in these spirits furnishes a useful criterion for evaluating the character of these spirits.  相似文献   

18.
Phytosterols have been recovered from the deodorizer distillate produced in the final deodorization step of vegetable oil refining by various processes. The deodorizer distillate contains mainly free fatty acids (FFAs), phytosterols, and tocopherols. The presence of FFAs hinders recovery of phytosterols. In this study, fermentation of soybean oil deodorizer distillate (SODD) with Candida tropicalis 1253 was carried out. FFAs were utilized as carbon source and converted into cellular components as the yeast cells grew. Phytosterols concentration in SODD increased from 15.2 to 28.43 % after fermentation. No significant loss of phytosterols was observed during the process. Microbial fermentation of SODD is a potential approach to concentrate phytosterols before the recovery of phytosterols from SODD. During SODD fermentation, sterols-rich yeast cells were produced and the content of total sterols was as high as 6.96 %, but its major sterol was not ergosterol, which is the major sterol encountered in Saccharomyces cerevisiae. Except ergosterol, other sterols synthesized in the cells need to be identified.  相似文献   

19.
肉桂油成分分析及肉桂醛体外抗肿瘤活性研究   总被引:2,自引:0,他引:2  
目的探讨肉桂醛对不同肿瘤细胞株的生长抑制作用。方法通过水蒸气蒸馏法提取肉桂油,用气相色谱—质谱联用仪进行肉桂油成分分析;采用噻唑蓝(MTT)比色法检测肉桂醛对体外培养的人宫颈癌细胞系HeLa细胞株、人肺癌细胞系A-549细胞株和人肝癌细胞系HepG2细胞株的生长抑制作用,计算半数抑制浓度(IC50)。结果肉桂油的收率为1.96%,分析了肉桂油中的10种成分,主要为肉桂醛,占总馏出峰面积的93.94%;肉桂醛能抑制人宫颈癌细胞系HeLa细胞、人肺癌细胞系A-549细胞和人肝癌细胞系HepG2细胞增殖,且呈剂量依赖性,IC50值分为0.20、0.36和0.73 mg/mL。结论肉桂醛具有体外抗肿瘤活性。  相似文献   

20.
Commercial formulations of the pesticides: Guthion (azinphos methyl), Sencor (metribuzin), Lorox (linuron), Reglone (diquat), Daconil (chlorothalonil) and Admire (imidacloprid) were studied for their genotoxicity by 32P-postlabeling. Metabolites of the pesticides were obtained enzymatically using arochlor induced rat liver S9 fraction, in an NADPH generating system. The resulting metabolites were reacted with calf thymus DNA and the DNA was analyzed for presence of adducts by either the nuclease P1 or butanol enrichment. Nuclease P1 enrichment resulted in adducts for all the pesticides. Compared to the level of adducts in control DNA, the levels in pesticide-treated DNA were higher for all the pesticides, except Daconil. The increase in adduct numbers for pesticide-treated DNAs ranged from 4.9-12.4 times the control-DNA indicating pesticide genotoxicity in this in vitro system. Enrichment using butanol extraction gave three adducts unique to Sencor-DNA. These adducts were different from those obtained with nuclease P1 enrichment of the same. B()P was the positive control for the in vitro metabolism, and two adduct enrichment procedures: nuclease P1 digestion and butanol extraction.  相似文献   

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