Extraction with chloroform/methanol

Traps with Bio-Sep beads amended with [ Cg]-benzene and [ C]-toluene were used to assess biodegradation in an aquifer (Geyer et al. 2005). Beads were lyophilized after exposure, lipids were extracted with chloroform-methanol, and the fatty acids and values analyzed. High enrichment of was observed in several fatty acids, which showed that the label from the substrates had been incorporated. In addition, there were differences in the abundance of the fatty acids in beads amended with benzene or toluene that suggested the existence of different microbial degradative populations. 

The stability of niclosamide was studied in simulated gastric and intestinal juices, with and without enzymes, after incubation at 37°C. The remaining intact drug and its degradation products (2-chloro-4-nitroaniline and 5-chlorosalicylic acid) were extracted with chloroform/methanol (5 1) and determined by TLC and HPLC. The drug was stable in these media for at least 6 h [68]. 

The question as to the potential availability of the requisite amphiphilic precursors in the prebiotic environment has been addressed experimentally by Deamer and coworkers, [143,145] who looked into the uncontaminated Murchison chondrite for the presence of such amphiphilic constituents. Samples of the meteorite were extracted with chloroform-methanol and the extracts were fractionated by thin-layer chromatography, with the finding that some of the fractions afforded components that formed monomolecular films at air-water interfaces, and that were also able to self-assemble into membranous vesicles able to encapsulate polar solutes. These observations dearly demonstrated that amphiphiles plausibly available on the primitive Earth by meteoritic infall have the ability to self-assemble into the membranous vesides of minimum protocells. ... 

L1p1d extraction with chloroform/methanol c1ean-up with column chromatography elution with acetonitrile, hexane and methylene chiori de. 

Lipids can be identified and quantified using thin-layer chromatography (TEC) and gas chromatography (GC) (Galliard, 1968). Extraction of lipids is achieved by homogenizing potato tubers with isopropanol in a blender, followed by a series of filtrations and extractions with chloroform-methanol (2 1). Chloroform is removed by rotary evaporation and the residue is redissolved in benzene-ethanol (4 1). This extract is passed through a DEAE-cellulose column, and the fractions collected are subjected to TEC on 250 p,m layers of silica gel G, using three solvent systems. Fatty acid methyl esters for GC analysis are prepared by transmethylation of the parent lipids, or by diazomethane treatment of the free fatty acids released by acid... 

Fig. 4.5.7 TLC analysis of short LLO. Fibroblasts derived from a control (lane 1, left) andaCDG-Ii patient (lane 2, right) were metabolically labelled for 30 min with [2-3H] mannose. Short LLO were extracted with chloroform/methanol (3 2) and further analysis carried out by TLC in a running buffer containing chloroform/methanol/LLO (65 25 4). The position of the origin, and the positions of [3H]ManiGlcNAc2-PP-dolichol and [3H]Man2GlcNAc2-PP-dolichol are indicated...

We have observed such a transition in intact membranes of M. laidlawii which occurs at the same temperature as in the membrane lipids dispersed in water (77). Figure 11 shows representative endothermic transitions of membranes and lipids in water. Membranes were prepared for calorimetry by sedimenting at high speed, then 90-100 mg. of packed pellet were sealed in a stainless steel sample pan. The material was neither dried nor frozen before examination. Total membrane lipids were extracted with chloroform-methanol 2 1 v/v then dried and suspended in water. Lipids from the membranes of cells grown in the usual tryptose medium without added fatty acids are shown in a, while b and c are scans of intact membranes from the same cells. In b the membrane preparation had not been previously exposed to temperatures above 27 °C. The smaller transition at higher temperature probably arises from... 

HPLC of galactolipids from a membrane treated with galactose oxidase. The membrane treated with galactose oxidase is extracted with chloroform/methanol as described above. The extract containing up to 1 mg of total lipids is shaken with a solution of 2 mg of dinitrophenylhydrazine HC1 in 100 pi pyridine for 2 h at room temperature. The solvent is evaporated to dryness under a... 

Cells which were treated with neuraminidase prior to lipid extraction were washed twice in PBS and resuspended at 10 cells per ml in PBS containing 50 units neuraminidase per ml or in PBS alone (control). The cell suspensions were incubated 5 min at 37°, centrifuged at 1200 rpm for 10 min at 4° in an International PR2 and washed once with cold PBS. The cells were resuspended in hypotonic Tris-HCl, centrifuged and extracted with chloroform-methanol in the manner described above. 

Glycolipid analysis. Gangliosides were extracted with chloroform-methanol (2 1), purified on Sephadex G-25 columns and separated into individual species by thin-layer chromatography as described previously (12). 

Plasma Extraction with chloroform/ methanol HPLC (C18) MS ESI hybrid quadrupole time of flight 95 (43)... 

Tissue Extract with chloroform/methanol GC/MS 0.02 gig No data Hillman et al. 1975... 

Tissue Extract with chloroform/ methanol GC 5 g/g 60 90 Jaeger and Rubin 1972... 

Food Extract with chloroform/methanol, dry with sodium sulfate, dissolve in ethyl ether GC/FID 0.01 1.0 ppm 58 90 Ishida et al. 1981... 

After the seromucoids were precipitated with phosphotungstate-HC1, they were exhaustively extracted with hot alcohol-ether (3 to 1 by volume), followed by two hot extractions with chloroform-methanol (1 to 1). The combined solvent extracts were evaporated on the steam bath under nitrogen and the lipides taken up with petroleum ether. The petroleum ether extracts were washed several times with water containing acetate and 0-hydroxybutyrate and acetoacetate (10). 

The thin-layer chromatography profile alone will provide a quite accurate evaluation of the extent of the cleavage reaction. If a more quantitative assay is desired, then another plate—usually a preparative type—can be run and individual components can be identified by TNS spray, removed by scraping, and extracted with chloroform-methanol-water (1 2 0.8, v/v) and analyzed after phasing the desired compound into chloroform. Then, the yield of the phosphorus-containing compound can be determined. The methyl esters can be assayed by GC-MS. The presumed alkylglycerophosphocholine then can be studied further. 

In the LSE, a glass-type equipment is used and the extractions with chloroform, methanol and n-hexane are carried out. The LSE is usually takes about 12 hours with 5 g of each sample. Since we discussed elsewhere the experimental procedures of both the SFE and the LSE, we omit here further descriptionsfl, 2],... 

No single satisfactory procedure has been discovered that avoids all these complications. Thus, extraction conditions must be adapted to the tissue under study and to the quantity and type of lipid desired. As a point of departure, the total lipids of a wet tissue can usually be extracted with chloroform-methanol mixtures according to the procedure of Folch (or one of several variants of... 

The incubation mixture contained ornithine, pyridoxyl phosphate, and the enzyme. After incubation for 1 hour, the reaction was terminated with perchloric acid. The precipitate was removed by centrifugation, the supernatant extracted with chloroform-methanol (2 1), and the aqueous layer applied to a CellexP column. The putrescine was eluted, reacted with fluorescamine, and quantitated by HPLC. 

The variation in the weight percentage of tqtal solvent extractable (TSE) material (extraction with chloroform/methanol/toluene) and solvent extractable humic acid (SEHA) for the coal samples is... 

Bulgin s data show loss of DTA peaks at 114° and 135°C if SC is heated for 2 hrs at 100°C or extracted with chloroform methanol (2 1) (103). Rehydration restores the 114°C peak of the heated SC, but the 135°C peak is irreversibly lost. The reverse is true for extracted SC rehydration restores the 135 °C peak but not the 114 °C peak. These results suggest association of the 114°C peak with water in lipid-rich hygroscopic substance heating would drive oflF the water without destroying the lipids. However, the lipids would be removed by the chloroform methanol. The 135 °C peak may be associated with water bound by protein surfaces which resist chloroform-.methanol yet are denatured by heat. Perhaps dehydrated protein surfaces become bonded together thereby eliminating hydrophilic sites. 

For quantitation of cholesterol and its derivatives in muscle and liver tissues, the extracts of the tissue homogenates are evaporated, dissolved in a mobile phase such as hexane-isopropanol, and injected onto a normal-phase column. For analysis of soybean oil by reversed-phase HPLC, after extraction with chloroform-methanol (9 1), the neutral lipids. 

The preparation of a lipid sample includes extraction of the lipid material from the examined object (seeds, tissues, food, etc.), choosing among the several widely accepted procedures. The extraction with chloroform-methanol (2 1) (the Folch extraction) is the most popular. A solution of known concentration in hexane or di-chloroethane is prepared and a suitable aliquot is applied on the plate as a small spot or, better, as a narrow band. Two, three, or more solvents, mixed in different proportions, give the mobile phase. Development is performed in common tanks (Desaga type, for example), in the ascending mode. For fine separations, cylindrical or sandwich-type tanks provide better results. 

The unusual solubility behavior of, for example, the Tay-Sachs brain tissues is due to qualitative and quantitative differences in the composition of the appropriate lipid.211 The isolation and purification of these anomalous gangliosides were carried out similarly to those for the gangliosides of normal tissues, for example, by the method of Folch and coworkers.182 In this method, the brain tissues are extracted with chloroform-methanol-water, the extract is washed with potassium chloride solution, and the extracted material is separated on a column of silicic acid by elution with an increasing concentration of methanol in chloroform. 

For preparation of CMHs, a lipid extract from fungal cells is obtained by successive extractions with chloroform/methanol (2 1 and 1 2 v/v). These extracts are usually combined and dried, yielding a crude lipid mixture. The crude extract is subsequently partitioned according to Folch et al. [27], in which the lower phase containing neutral glycosphingolipids is taken for further analysis. 

HIRE was also grown in mycological broth (without Mg3(P04)2 12H20) for 21 days unshaken (12 L), but the harvest protocol of the mycelial mat was altered. Following filtration, the mycelium was thoroughly pulverized with the Omnimixer, then soaked in methanol for 24 hr. The methanol was removed by filtration, and the mycelial marc was then extracted with chloroform/methanol (1 1). The methanol extract retained both the NMR activity and the brine shrimp toxicity. The methanol extract of the mycelial mat (10.53 g) was applied to a LH-20 size exclusion column (methanol). Seventeen fractions eluted, but all pertinent activity was concentrated in fraction 8, which was ultimately resolved by normal phase CCCC (chloroform/methanol/water, 25 24 20). Fraction 3 was brine shrimp toxic, and was found to be identical to roquefortine C... 

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