Cent Aqueous Ethanol Research Articles

Ultrasonic extraction and HPLC determination of anthraquinones, aloe‐emodine, emodine, rheine, chrysophanol and physcione, in roots of Polygoni multiflori

Polygoni multiflori, one of traditional Chinese herbal medicines for the treatment of various diseases commonly associated with aging, is known to contain active anthraquinone ingredients. However, the content of the anthraquinones varies among P. multiflori samples with collection season and sites. Thus, simple, reliable and accurate analytical methods for determining of anthraquinones in P. multiflori products are needed for the quality control and pharmacological studies. To develop an HPLC method for the simultaneous determination of five anthraquinones, aloe-emodine, rheine, emodine, chrysophanol and physcione, in the roots of P. multiflori. Anthraquinones were extracted from the roots of P. multiflori using aqueous alcohol solutions or hot water under ultrasonication. Separation and quantitation of anthraquinones was accomplished using a reversed-phase C18 column with the mobile phase of methanol-water-phosphoric acid (600:400:1), and the detection wavelength of 254 nm. Seventy per cent aqueous ethanol showed the highest extraction efficiency for anthraquinones from roots of P. multiflori when compared with four other extraction solvents tested. All calibration curves were linear over the concentration range tested with the square of correlation coefficients >0.999. The detection limits (S/N = 3) were 0.89, 1.1, 1.6, 1.7 and 2.0 ng for chrysophanol, aloe-emodine, rheine, emodine and physcione, respectively. Emodine and physcione were found in the samples tested at concentrations of 0.341 and 0.197 mg/g, respectively. The described HPLC methods are simple, accurate and selective techniques for separation and quantification of anthraquinones in roots of P. multiflori and other plant samples.

High‐temperature migration of antioxidants from polyolefins

Migration rates of radiolabelled antioxidants, Irganox-1010 (I-1010) and Irganox-1076 (I-1076), were measured from low- and high-density polyethylenes (LDPE, HDPE) and polypropylene (PP) at temperatures up to 135 degrees C. Water, 8 and 95 per cent aqueous ethanol and corn oil were employed as food simulating liquids (FSL). The experiments were conducted in a high-pressure cell in a manner that allowed contact between the polyolefin plaque and the FSL only during the test period and not while being heated. The migrations of the antioxidants varied with the square root of time, and the Fickian diffusion coefficients could be correlated with temperature in an Arrhenius fashion. Under comparable test conditions, antioxidant migrations were largest from PP for aqueous simulants, but for non-aqueous simulants the highest losses were from LDPE. In both instances lowest losses were from HDPE. In most instances there was little difference between the migration behaviour of I-1010 and I-1076. A few tests were conducted to measure the antioxidant migrations to foods. The losses were usually larger than those to water but below those to corn oil.

The Sapogenins Of The Seeds Of Four Lupin Species

The saponin fractions of defatted lupinseed meals can be extracted by means of 20 per cent aqueous ethanol. Acid hydrolysis of the extract affords, from each species, a characteristic range of sapo...

The interactions of chloranil in aqueous solvents—I The absorption spectrum of chloranil in 50 per cent aqueous ethanol

A study has been made of the visible and ultra violet absorption spectra of a solution of chloranil in 50 per cent aqueous ethanol when buffered at different pH values. The changes in the spectra with time have also been studied. It is shown that the characteristic purple colour of an aqueous solution of chloranil is not due to chloranilic acid. Spectral details are also given for trichlorohydroxyquinone in 50 per cent aqueous ethanol.

Photodecomposition of N-alkyl-N-nitrosourethanes.

IN the course of investigations of the carcinogenic action of N-methyl-N-nitroso-urethane (NMU)1 it was observed that dilute solutions of this compound in aqueous ethanol, when left in direct sunshine, became decolorized and deposited colourless crystals. Solutions kept in the dark remained yellowish and free from crystalline deposit. This observation was confirmed by exposing 1 per cent solutions of NMU in 10 per cent aqueous ethanol to direct sunshine, or to the light from a mercury-vapour lamp. The solutions became decolorized in the course of several hours or days with deposition of colourless crystals. Red, green, yellow or orange filters, but not blue ones, protected the NMU solutions from this type of decomposition, indicating that the effect is due to the light near the ultra-violet range.

Carbohydrate absorption in cestodes from elasmobranch fishes

Eight species of cestodes from elasmobranch fishes absorbed glucose and galactose. Lacistorhynchus tenuis and Phyllobothrium foliatum absorbed maltose readily, and the latter took up this disaccharide much more rapidly than glucose. Several glycosides and otherphenolic derivatives exerted a predominantly inhibitory effect on the carbohydrate consumption by the worms. However, naringenin, phlorizin, and rutin accelerated the rate of glucose uptake by Onchobothrium pseudo-uncinatum, and a similar result was obtained by exposing Calliobothrium verticillatum to a medium containing p-(2,4-dihydroxyphenylazo)benzene sulfonic acid. Quercetin, diethylstilbesterol, p, p′-biphenol, and bis( p-hydroxyphenyl) methane did not block glucose consumption by C. verticillatum and L. tenuis. The worms contained at least three carbohydrate fractions, two of which were stable to alkaline digestion. One of the alkali-stable fractions precipitated in 50 per cent aqueous ethanol, whereas the other did not do so. Inermiphyllidium pulvinatum, L. tenuis, and O. pseudo-unicinatum synthesized a net increase in polysaccharide during four hours' incubation in the presence of glucose. A substance that was presumably lactic acid was excreted by all eight species of cestodes.

I-(Indole-3-acetyl)-beta-D-glucose, a new compound in the metabolism of indole-3-acetic acid in plants.

STUDYING the fate of exogenously applied indole-3-acetic acid (IAA) in pea epicotyls, we observed, besides indoleacetylaspartic acid1 (IAAsp), a trace amount of a compound which showed definitely indole reactive properties and which was split on alkaline hydrolysis into IAA. The amount of this metabolite proved too small for identification, therefore we carried out a rough survey on one species from 20 plant families using 2-14CIAA in the hope of finding an accumulation of this metabolite. This unknown compound was found in the leaves of the monocotyledonous plant Colchicum neapolitanum Ten. to about 65 per cent of the total amount of IAA taken up, the rest being unchanged IAA (20 per cent) and minor components (Fig. 1, top). IAAsp was detected, if at all, only in very small quantities. In order to isolate a larger amount of this compound, 70 gm. of mature Colchicum leaves were cut into pieces and incubated with 1 litre of a 4 × 10−4 M solution of IAA for 24 hr. with good aeration. The compound was extracted from the leaves with boiling 80 per cent aqueous ethanol; the extract was then concentrated to a small volume and made up to a powder with ‘Hyflo supercel’ and then extracted in a Soxhlet-type extractor for 6 hr. with ether. The ether containing only the IAA was discarded, and extraction continued with ethyl acetate for another 6 hr. This solution was taken to dryness and the residue containing the compound chromatographed as streaks on Whatman No. 3 paper in n-butanol / glacial acetic acid / water (5 : 1 : 2.2, R F 0.56) and in isopropanol / benzine / water (55 : 30 : 11, R F 0.39). By elution and rechromatography between the two solvents, the derivative could be purified and resulted finally in 6.05 mgm. of a highly purified, non-crystalline material. The compound was located on the paper by spraying with p-dimethylaminobenzaldehyde.

A new spraying agent for paper chromatography of carbohydrates and polyols.

WHILE investigating the chromatographic separation of sugars upon filter paper impregnated with sodium borate buffer (0.05 N borax, pH 9.18) it was found that the carbohydrates showed up prominently on spraying with 80 per cent aqueous ethanol containing either 1 mgm./ml. of phenolphthalein or phenol red just made alkaline with sodium hydroxide. Phenolphthalein gave rise to white spots on a purple background and was rather more effective than phenol red, which gave yellow spots on a purple background.

Adrenal cortical hormones in human placenta.

11-Dehydro-17-hydroxycorticosterone (cortisone) and a number of other adrenal cortical hormones and their metabolites have been found in human placentas. The ethyl acetate extract of a finely minced placenta, freed from blood so far as possible, was evaporated to small volume, washed with 0.2 M sodium carbonate, 0.2 N hydrochloric acid and 0.1 M sodium acetate and evaporated to dryness. The residue was taken up in petroleum ether and extracted with 70 per cent aqueous ethanol. The united lower layers were evaporated to dryness, and the residue was taken up in benzene which was extracted ten times with equal volumes of water. The united aqueous layers were extracted with chloroform, and the extract dried and evaporated to dryness. The residue was examined by paper chromatography at 37° using a benzene–50 per cent methanol system1. Several α,β-unsaturated ketonic substances were present. That present in largest amount reduced triphenyl tetrazolium chloride, had the same RF value as cortisone and gave a blue colour with iodine. Elution with 90 per cent ethanol was followed by evaporation to dryness and acetylation with acetic anhydride in pyridine. The resulting acetate was examined by paper chromatography at 37° using a benzene–petroleum ether (1 : 1): 80 per cent methanol system, and was found to have the same RF value as cortisone acetate. Rough estimation of the fluorescence in ultra-violet light after treatment with methanolic caustic soda indicated a yield of approximately 100 µgm. cortisone per placenta. Traces of 17-hydroxycorticosterone are also present, and at least three other α,β-unsaturated 3-ketosteroids which are at present unidentified.