Chloroform-methanol extraction

Partially purified brain gangliosides Chloroform-methanol-extracted >500... 

Chloroform-methanol extracts of Borrelia burgdorferi were used for the identification of lipids and other related components that could help in the diagnosis of Lyme disease [58]. The provitamin D fraction of skin lipids of rats was purified by PTLC and further analyzed by UV, HPLC, GLC, and GC-MS. MS results indicated that this fraction contained a small amount of cholesterol, lathosterol, and two other unknown sterols in addition to 7-dehydrocholesterol [12]. Two fluorescent lipids extracted from bovine brain white matter were isolated by two-step PTLC using silica gel G plates [59]. PTLC has been used for the separation of sterols, free fatty acids, triacylglycerols, and sterol esters in lipids extracted from the pathogenic fungus Fusarium culmorum [60]. 

A drin and Dieldrin Metabolism.— The in vivo metabolism of the chlorinated alicyclic insecticides, aldrin and dieldrin, has been measured. Fish were exposed to l c-labelled aldrin or dieldrin for 6 hours. The metabolism of each compound was monitored by thin layer chromatography of hexane and chloroform-methanol extracts of liver homogenates, followed by liquid scintillation counting of the spots (5,15,16). 

Gene expression inhibition. Chloroform/ methanol extract (1 1) of the dried leaf, in cell culture, was active on hepatoma-Cos-7, IC50 600.0 pg/mL vs TAT-dependent activation of HIV promoter hioassay - . Hepatotoxic activity. The leaf, taken orally by a female adult, was active - . A patient consumed 15 tablets of the leaf per day for 4 months. Approximately 1 year after stopping consumption, liver enzymes returned to normal and fatigue was no longer a complaint - ". Infusion of the dried leaf, taken orally by a female adult at variable doses, was active. The 60-year-old woman who took Lama tridentata for 10 months developed severe hepatitis for which no other cause could be found. Despite aggressive supportive therapy, the patient s condition deteriorated and required orthotropic liver transplantation - " . Dried leaves, administered orally to adults at variable doses, were active. A public warning has been issued by the US Centers for Disease Control based on reports of liver toxicity after use of Lama tridentata tea - " k Dried leaves, administered orally to adults of both sexes at variable doses, were active - ". The plant, administered orally to adults at variable doses, was active - ". Dried leaves, administered orally to adults at variable doses, were active. One case of hepatotoxicity induced by Larrea tridentata taken as a nutritional supplement was reported - ". Thirteen patients were identified for whom Larrea tridentata tincture for internal use was prescribed. Additionally, 20 female and three male patients were identified from whom an extract of Larrea tridentata in castor oil for... 

After 1 h add 1.0 ml 0.73% NaCl to the chloroform/methanol extracts. Vortex and centrifuge for 5 min at 1000 xg to separate the phases. Pipette the lower chloroform phase into a Pyrex tube. Extract the upper phase twice with 1 ml chloroform and add these chloroform lower phases to the first chloroform phase take the combined chloroform phases to dryness with nitrogen. 

In particular compound 40 was purified by Sephadex LH-20 column from the chloroform-methanol extract, while compounds 41-42 were obtained similarly by using Sephadex LH-20 column and Lobar Lichroprep RP 8 chromatography. 

Table 4. Effects of varions lipid fractions of chloroform methanol extract (1 1,v/t) (a), acetone- soluble and -insoluble fractions (b), and n-hexane-soluble and -insoluble fractions (c) on tumor volume at 20 d and tumor weight at 21 din sarcoma 180-bearing mice1...

P Meneses, JN Navarro, T Glonek. Algal phospholipids by 31P NMR comparing isopropanol pretreatment with simple chloroform/methanol extraction. Int J Biochem 25 903-910, 1993. 

Experimentally, it is possible to incubate a radiolabeled PAF sample, as described above, with phospholipase A2, and at the end of the desired time period the usual chloroform-methanol extraction can be performed. The chloroform-soluble fraction is applied to a silica gel G thin-layer plate, with appropriate standards in a separate lane, and the plate developed in a solvent system of chloroform-methanol-water (65 35 7, v/v). If the radioactivity is now located at an Rf value near 0.10, which would be comparable to... 

On the basis of the experience accrued so far, the extraction efficiency can be affected by both the nature of the sample under test and the As species actually present in the sample. The lipid content of the sample and the presence of As species with hydrophobic residues play a key role in this context. As a consequence, it may be useful to remove or partition lipids with an organic solvent prior to the methanol-water extraction in order to increase the extraction efficiency. This approach is also viable to prevent emulsification of methanol and lipids, which could otherwise significantly reduce the extraction efficiency [26]. Thus, sample preparation prior to As speciation usually starts with the chloroform-methanol extraction, followed by centrifugation of the sample solution to remove solid particles. Subsequently, after the addition of methanol and water, the supernatant is separated in a funnel. The amount of As remaining in the organic phase is usually quantified as total As by wet digestion after solvent evaporation. Obviously, this entails the loss of all speciation information related to the lipid-soluble As species [2]. Speciation analysis is finally carried out on the methanol-water phase, usually after solvent evaporation (see Table 19.2). 

Triacylglycerols (esp. triolein) Chloroform-methanol extraction, HPLC with detection at 208 nm GC of derivatized or free fatty acids. Bacterial lipase Veeraragavan (1990), Choi and Jeon (1993)... 

As an alternative to traditional solvent extraction methods, the extraction by supercritical (SC) fluids has been used in tocol analysis. This is an environmentally friendly technique as little or no solvents are used. Extraction parameters, e.g. temperature and fluid density, are easily optimized and managed, and as the extraction is fast it is thus suitable for routine work with many samples. SC carbon dioxide has been used to extract tocols from barley (Fratianni et al, 2002), dried bay leaves (Gomez-Coronado et al, 2004), and garden cress seeds (Diwakar et al, 2010). Extractions were carried out in single or multiple steps and with different fluid densities controlled by extraction pressures. Tocol yields from barley were 5% and 14% less than by Soxhlet and chloroform-methanol extractions (Fratianni et al, 2002), yields from garden cress seeds were 26% less than by Soxhlet extraction (Diwakar et al, 2010), and a- and y-tocopherol yields from dried bay leaves were 22% and 40% less than by acetone extraction (Gomez-Coronado et al, 2004). Despite lower recoveries of tocols, the SC carbon dioxide extraction methods were considered comparable to the classical extraction methods (Fratianni et al, 2002). 

Besides the unidentified compound with spacings of 3.1, 4.7, and 9.4 A reported by Garson et al. (1991), Bouwstra et al. (1992b) also found two other reflections, at 3.6 and 7.17 A, that could not be identified. The reflections were arc shaped and did not change upon heating between 20 and 120°C and are therefore most probably due to thermostable proteins because they were also observed in chloroform/methanol-extracted SC. 

Figure 6 Average CH2 symmetric stretching frequency of stratum comeum lipids, isolated by chloroform methanol extraction, plotted as a function of temperature (closed square, first heat open square, second heat) at constant hydration (95% RH). Error bars, SD. (From Ref. 40.)...

Examples of the resulting plots of the desorption rate vs. temperature are shown in Figure 12. Untreated corneum samples exhibit one maximum at about 80°C whereas ether extraction (90 min) produces a second lower temperature maximum in addition to the higher temperature peak. The low temperature peak perhaps indicates the presence of loosely bound water which can diffuse out of the corneum more easily than the primary sorbed water. The thermogram for the chloroform-methanol-extracted corneum reveals a single, broad peak indicative of a more general solvent damage to the corneum matrix. The thermal de-... 

Figure 24. Dynamic mechanical spectrum of dry human stratum corneum. Dashed line, control solid line, chloroform-methanol extracted (N2 atm, 1°C/...

Figure 29. Isometric contraction of human stratum comeum A, chloroform-methanol extracted B, control (7)...

The seeds of M. oleifera variety Mbololo yielded 26%, 31%, and 36% crude oil by cold-pressing, hexane extraction, and chloroform-methanol extraction (1 1, v/v), respectively (70). The seed oil was rich in total monounsaturated fatty acids and contained 74—75% oleic acid (Table 9). The total saturated fatty acids were... 

Even after cells were successively grown in BM, 10 to 30% of HD-1 dry cell weight was chloroform/methanol extractable lipophilic fraction with no addition of organic carbons to the media Electron microscopic observation of the cells showed that the cell surface was rather irregular, and many granules were accumulated inside the cell (Fig. 2). 

Fig. 8-98. Separation of inositol-1,4,5-triphosphate in a rat brain extract. — Separator column IonPac AS4A eluent 0.0264 mol/ Lp-cyanophenol flow rate 2 mL/min detection suppressed conductivity injection 50 pL of a chloroform/methanol extract (2 1 v/v) (taken from [89]).

Fig. 21.3 Typical positive ion MALDI-TOF mass spectra of a chloroform-methanol extract of LDL (a) and HDL (b). The insert emphasizes the most relevant mass range of the FIDL sample. The peak labeled with an asterisk is caused by the matrix. Reprinted with modification from Journal of Lipid Research 42 (2001) 1501-1508...

A reduction in chemically induced tumor incidence was observed in rats administered a chloroform-methanol extract of shatavari (Rao 1981). 

No mutagenic effects of ethyl acetate, methanol, or aqueous extracts of saffron were observed in the Salmonella/micro-some assay using S. typhimurium strains TA98 and TAIOO with or without metabolic activation (Yamamoto et al. 1982). No mutagenic effects of a 2 1 chloroform-methanol extract of saffron were observed in pig kidney cells or in trophoblastic placenta cells treated at concentrations of 100 mg/plate (Rockwell and Raw 1979). 

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