Preparation of Extract

Powdered drug (0.5g) is extracted for 5min on a water batli with 5ml methanol. General method, 

The filtrate is used for TLC 5pi (Aloe) and 20pl (Rheurn, Frarsgiiia, Cascara), meihanolic extract 

Setmae foliunt or fructus are extracted with 50% methanol 20pl is used for TIC. Senna 

Powdered drug (0.5 g) and 25 ml 7.5% hydrochloric acid are heated under reflux for Hydrolysis of 15 min. After cooling, the mixture is extracted by shaking with 20 ml ether. The ether anthraquinoiie phase is concentrated to about 1 ml, and 10 d is used lor TLC (e.g. Rhei radix). glycosides 

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This section summarizes the coals used for the project, some of their charactenstics, the preparation of extract and pitch materials, as well as the... 

Batch solvent extraction methods (e.g., by separatory funnel) for the preparation of extracts for biological analysis have a number of major problems. A large volume of solvent must be evaporated after the extraction step in order to obtain a sample sufficiently concentrated to be useful for biological testing. Artifacts can occur from solvent impurities, and reactions can occur during the evaporation process. 

The preparation of extracts of plant tissue containing active DPOs can be fraught with problems. In the intact plant tissue, both enzyme and substrate are present but are thought to be compartmentalized, with the enzyme bound to membranes and the native substrate ) present in the vacuole. As soon as the tissue is disrupted, these can react together with the very real risk of a suicidal inactivation of the enzyme by its own reaction products. As a result, most isolation procedures for DPOs include additions of ascorbate and/or cysteine to prevent the formation of the reactive quinones. Assuming that the enzyme is... 

Isolation of embryos and preparation of extract were carried out as reported previously (11). The main aim is to remove contaminating endosperms from embryos by washing (steps 5 and 6). 

The bark was air dried and then put through a hammermill using a 1/16-inch screen. The entire product was used in the preparation of extractives. 

PLATE 8.1 Spices and herbs used in the preparation of extract (Source Abrol, 2009). 

Preparation of Extracts for Chromatography. The dried ethanolic extract was dissolved in 2 ml. of 10% (v./v.) 2-propanol, shaken with an equal volume of chloroform, and centrifuged. The chloroform layer was discarded. The trichloroacetic acid extract was taken up in 2 ml. of water and extracted four times with an equal volume of ether to remove trichloroacetic acid and lipides. The ether extract was discarded. 

Wey AB, Zhang C-X, Thormann W. Head-column field-amplified sample stacking in binary system capillary electrophoresis. Preparation of extract for determination of opioids in microliter amounts of body fluids. J Chromatogr A 1999 853 95. 

Smith, H., Keppie, J., Stanley, J.L. (1953). The chemical basis of the virulence of Bacillus anthracis. I Properties of bacteria grown in vivo and preparation of extracts. Br. J. Exp. Pathol. 34 477-85. 

Gegenheimer, P. (1990). Preparation of extracts from plants. Meth. Enzymol. 182, 174-193. 

Aldehydes can be obtained by the use of the general reaction, which in many cases serves as a method of preparation, of extracting two hydrogen atoms from a primary alcohol by oxidation. 

Preparation of Extracts. Leffler (L2) and others have previously used isopropanol as a lipid solvent for determining cholesterol. Connerty et al. (C6) and Lofland (L4) also showed that triglycerides and phospholipids are extracted quantitatively. Under our extraction conditions, complete recovery of these lipid fractions is obtained at a serum-to-solvent ratio of 1 10 through 1 25. We routinely use 1 20 dilution (0.5 ml of sera+ 9.5 ml of isopropanol). We find that the addition of Lloyd s reagent removes bilirubin and other chromogenic material present in serum, as well as approximately 80% of the phospholipids present. 

At present all automated techniques for the determination of phospholipids require the manual preparation of extracts. Some investigators carry out the destruction of organic material manually others have automated this step. The colorimetric analysis for phosphorus is performed on an automated basis. 

Preparation of Extracts. Screw-capped culture tubes (16 X 150 mm) with Teflon-lined caps are used for carrying out the extractions. For sera or blank, use tubes containing 9.5 ml of isopropanol. While mixing the contents of the tubes on a Vortex mixer, add 0.5 ml of serum or 0.5 ml of 0.9% NaCl. Cap tubes, centrifuge, and transfer to a clean tube if extracts are to be stored, or sample directly if digestions are to be done at once. 

PREPARATION OF EXTRACTS FOR GAS CHROMATOGRAPHIC ANALYSTS AND GAS CHROMATOGRAPHIC ANALYTICAL CONDITIONS... 

PREPARATION OF EXTRACTS FOR GASCHROMATOGRAPHIC/MASS SPECTROHETRTC ANALYSTS... 

This procedure describes the preparation of nuclear and cytoplasmic extracts from cells grown in suspension (2-201) and is essentially as described by Dignam et al.1 and modified by Jamison and Garcia-Bianco.2 A procedure for small-scale preparation of extracts from HeLa cells grown as monolayer has been described by Lee and Green.3 The latter procedure is recommended when the cell material is scarce, if radioactively labelled extracts are made, if several extracts from parallel cultures, or if expensive growth conditions are necessary for cell propagation. 

Preparation of extracts 15 g of Crataegus herb were percolated with 250 ml 70 % aqueous acetone (column dimensions. 0 2 x 25 cm). Acetone was evaporated below 30 °C and the aqueous layer was extracted four times with 50 ml iso-oclane and four times with 50 ml ethyl acetate (both solvents presaturated with water). Combined organic phases were evaporated below 30 QC, dissolved in 3,0 ml 50 % aqueous methanol, filtered over a 0.45 pm filter and analyzed by HPLC. The water phases were lyophilized, dissolved in 10.0 ml 50 % aqueous methanol, filtered over a 0.45 pi filler and analyzed by HPLC. 

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