Ethanol extraction

A certain amount of hydrolysis of the original acetamide to acid and ammonia always occurs, and the final amine always contains traces of ammonia. This is separated by extracting the mixed anhydrous hydrochlorides with absolute ethanol, which dissolves the amine hydrochloride but not the ammonium chloride filtration of the hot ethanolic extract removes the ammonium chloride, whilst the amine hydrochloride crystallises readily from the filtrate on cooling. 

The aqueous solution is then concentrated to dryness at an outside temperature of 40° to 45°C and at low pressure. The residue, obtained by drying in a vacuum at 40° to 45°C is triturated in a mortar with ethyl ether and, after filtration, is extracted with 3,400 ml boiling absolute ethanol. The ethanol extract is separated from the undissolved part by filtration, cooled and the product which crystallizes by cooling is filtered and dried at 40°C in a vacuum. In that manner the disodium (4,4 -disulfoxy-diphenyl)-(2-pyridyl)-methane bi-hydrate is obtained, which takes the form of a white solid, according to U.S. Patent 3,528,986. 

Isolation from ethanolic extracts of fruits of UmbelliferaA/n/wi visnaga. 

A major metabolite was detected in the ethanol extract of 2,7-dichlo-rodioxin-treated soils. The metabolite was less mobile than DCDD in benzene-acetonitrile on TLC. The metabolite was eluted from the silica gel and methylated with diazomethane. The methylated metabolite was rechromatographed in benzene and migrated to the solvent front, suggesting a polar group on the non-methylated metabolite. 

Choi et al., 2001 Murine osteoblastic MC3T3 cells Soybean ethanol extract (0.05 g/1) stimulated osteoblastic function (DNA synthesis, collagen synthesis). 

Bergeron, C. et al.. Comparison of the chemical composition of extracts from Scutellaria lateriflora using accelerated solvent extraction and supercritical fluid extraction versus standard hot water or 70% ethanol extraction, J. Agric. Food Chem., 53, 3076, 2005. 

Watanabe, T. et al., Separation and determination of yellow and red Safflower pigments in food by capillary electrophoresis, Biosci. Biotech. Biochem., 61, 1179, 1997. Fekrat, H., The application of crocin and saffron ethanol-extractable components in formulation of health care and beauty care products. Proceedings of International Symposium on Saffron Biology and Biotechnology, Fernandez, J.A. and Abdullaev, R, Eds., Albacete, Spain, 2004, p. 650. 

Influence of Ethanol Extracts of Soil and Fescue Plants... 

Table III. Length of shoots and roots of rape and birdsfoot trefoil seedlings grown in nutrient solutions containing ethanol extracts ...

Table II shows data obtained by sequential n-hexane and ethanol extractions. The amount of extractables was below 10% in most cases indicating satisfactory MA-PIB-MA incorporation into the PDMAAm backbone.

Table II shows data obtained by sequential hexanes and ethanol extractions of the desilylated networks. Attempts to extract the networks prior to desilylation failed because the samples swelled to such a great degree that they lost their mechanical integrity and disintegrated. The amount of hexanes extractable material is less than 3% in all cases which indicates high copolymerization yields. Ethanol extractables were not determined because the presence of the byproducts of the desilylation, which are in the ethanol, would have given artificially high readings.

Hydroalcoholic extracts are made when the active constituents are insoluble in water or when a concentrated dosage form is desired. Hydro alcoholic extracts use concentrated alcohol in varying proportions with water as a solvent. Hydroalcoholic extracts are categorized as tinctures or fluid extracts, depending on the amount of alcohol used. Some patients who simply do not like the taste of alcohol may be counseled to put the dosage of tincture drops into a cup of hot liquid and let it stand for a few minutes to evaporate off most of the alcohol before ingestion. An example of an ethanolic extract is echinacea [5,6]. 

Unfortunately, many clinical studies evaluating the efficacy of dietary supplements are flawed. Some of the flaws in the studies include non-randomization, being unblinded, lack of standardized products, small sample sizes, short treatment durations, and poorly defined inclusion and exclusion criteria. Many studies do not give detailed information about the dietary supplement used. When an herb is studied, the following information should be described plant species, part(s) used, product form (e.g., powdered crude herb, aqueous extract, ethanol extract, or aqueous alcohol extract) with stated proportions of water to alcohol, specifically extracted fractions, and quantities or concentrations used [48]. 

Stephadiamine (16) was isolated as a minor component from the ethanolic extract of the whole plant of Stephania japonica collected in Taiwan (6). The IR spectrum of stephadiamine (16) exhibited bands at 3375 (NH2) and 1720 cm 1 (5-lactone), and the H-NMR spectrum (Table II) showed the presence of one JV-methyl and two methoxyl groups. Its mass spectrum revealed a base ion peak at m/z 243 of stephamiersine-type cleavage (Table V) (6). 

Many explosions have been experienced dining the gravimetric determination of either perchlorates or potassium as potassium perchlorate by a standard method involving an ethanol extraction. During subsequent heating, formation and explosion of ethyl perchlorate is very probable. 

Results of experiments with water and ethanol extracts from sesquiterpene-enriched plants Achillea millefolium and Gaillardia pulchella are given in Table 2. The inhibitory effects are dependent on the solvents and the concentration of plant material. Strongest effects were observed mainly, for leaves and flowers. 

Table 2 The effects of water and ethanol extracts from allelopathically active plant species on the germination of Equisetum arvense microspores (amount of red-fluorescing microspores, % of control)... 

Plant species Organ Water extract (1 10 w/v) The ethanol extracts 1 1000 1 100 ... 

Original ethanolic extracts (1 10 w/v), were mixed with water to get final concentration. The ethanol concentration was not more 1/100 or 1/1000 and had no effect on the studied reaction. 

Chua M-T, Tung Y-T and Chang S-T. 2008. Antioxidant activities of ethanolic extracts from the twigs of Cinnamomum osmophloeum. Bioresource Technol 99(6) 1918-1925. 

In the PO-CL system, the compounds showing native fluorescence or that fluoresce after chemical derivatization can be detected. As examples of the PO-CL detection of native fluorescence compounds, dipyridamole and benzydamine in rat plasma [57] and fluphenazine [58] have been reported in the former method, the detection limits of dipyridamole and benzydamine were 345 pM and 147 nM in plasma, respectively. Diamino- and aminopyrenes were sensitively determined using TCPO and their detection limits were in the sub-fmol range [59], Carcinogenic compounds such as 1- nitropyrene and its metabolites, can also be determined by the HPLC-PO-CL system. Nonfluorescent nitropyrenes were converted into the corresponding fluorescent aminopyrenes by online reduction on a Zn column followed by detection 2-50-fmol detection limits were achieved in the determination of ethanol extracts from airborne particulates (Fig. 13) [60],... 

A shorter method of hydrolysis which may work as well follows dissolve 20 g alkaloid in 300 ml methanol and 300 ml 40% KOH and reflux two hours under N2 (if possible). Cool, saturate with C02 and evaporate in vacuum. Extract the residue with hot ethanol three times and dry, evaporate in vacuum the combined ethanol extracts to get (I). 

Nitropropanoyl esters of glucose from the roots of Lotus pendunculatus Cav. were determined by analysis of nitrate released on alkaline hydrolysis. This method was validated for quantitation of both total nitro compounds in ethanolic extracts and for individual components from TLC separations557. 

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