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PubMed1994

[C14-aminopyrine breath test and enzymatic liver tests in workers employed by the coke tar distillation department].

A group of 400 subjects divided into three sub-groups was examined. Group I consisted of 130 persons employed at the coke tar distillation department. Group II (controls) consisted of 70 persons also employed at the coke plant but free from occupational exposure. Group III was composed of 200 workers employed at the Building Factory. C14-aminopyrine breath test (ABT) was performed in 30 subjects randomly assigned from each group. A standard enzymatic liver test was assessed in all subjects examined. The range of tests performed did not permit to indicate the toxic effect of occupational environment on the liver tissue. Abnormal enzymatic liver test found in all groups could results, among others, from alcohol abuse among those tested. However, it was revealed that aromatic hydrocarbons to which workers of the coke tar distillation department were exposed to, stimulated the activity of the liver microsomal oxygenase assessed by ABT.

Adult↗

PubMed1998

[Sensitivity of Pseudomonas sp. strain isolated from distilled water to disinfectants].

The aim of the study was to compare Pseudomonas sp. strain isolated from distilled water and grown on the sterile filtrate from this water with the referent strain of Pseudomonas aeruginosa NCTC 6749 grown under the standard conditions, with the respect to their sensitivity to eight common disinfectants. Partly modified EN 1040 method was applied. The reduction factor (RF) for at least five concentrations of each of the products were determined. The linear relationship between concentration of the disinfectants and RF was established in a graphic form. Sensitivity of the strains was compared at the RF = 4. The WS strain was found to be more sensitivity than the referent strain to the disinfectants. The ratio concentrations of the solutions that were effective during 15 minutes against both the strains were; 1.3 for ethyl alcohol; 2.1 for glutaraldehyde; 1.7 for formalin; 1.85 for phenol. In the case of chloramine-T, the sodium salt of dichloroisocyanuric acid, and peracetic acid the ratios of concentrations were 156.0; 96.5 and 21.5 respectively. They indicate much higher sensitivity of the strain isolated from distilled water to these chemicals.

Disinfectants↗

PubMed2005

[Comparison of supercritical fluid extraction and steam distillation methods for the extraction of essential oils from Schizonepeta tenuifolia Briq].

Essential oil was extracted from Schizonepeta tenuifolia Briq. by supercritical fluid extraction (SFE) and steam distillation (SD). The components extracted were determined by gas chromatography with area normalization method and identified by gas chromatography-mass spectrometry (GC-MS). The optimal chromatographic conditions were: capillary column, SE-54 (30 m x 0.25 mm i.d., 0.25 microm); column temperature, 50 degrees C (3 min) --> (5 degrees c/min) 180 degrees C (2 min --> (10 degrees C/ min) 260 degrees C 50 min); split injection, split ratio 1: 50; injector temperature, 280 degrees C. Fifty-four components were identified for the essential oils extracted by SFE, and its main components were found to be pulegone, menthone, linoleic acid chloride etc. Thirty-nine components were identified for the essential oil obtained by SD, and its main components were found to be pulegone, menthone, limonene etc. The SFE method is better than the SD method in reliability stability and reproducibility, and is thus well suitable for similar applications involving for extraction of other traditional Chinese herbal medicines.

Chromatography, Supercritical Fluid↗

PubMed1996

Morphological and kinetic changes of carp (Cyprinus carpio) spermatozoa after initiation of motility in distilled water.

Studies on the flagellar movement of carp spermatozoa induced by dilution in distilled water allowed us to describe a sequence of early, rapid morphological and kinetic changes which begin at the very tip of the flagellum. They cause the progressive folding of the axoneme which ends stuck to the head within 90-120 seconds after the initiation of motility. However, the axonemal machinery remains functional as the folding can be reversed after transfer back into a high osmolality medium and partially folded flagella were able to propagate efficient waves along the non-folded proximal portion of the axoneme. The data also revealed that the membrane area of the terminal piece exhibits strong sensitivity to hypotonicity. These results suggest that in the normal freshwater medium, the brief swimming period allowing fertilization of oocytes is limited by the osmotic stress induced coiling of the carp sperm tail and not by ATP stores.

Animals↗

PubMed1985

Human tumor cell destruction by distilled water. An in vitro evaluation.

A distilled water lavage is sometimes used during tumor surgery in an effort to kill tumor cells spilled into a cavity or wound. To test the efficacy of this technique, a model study utilized nine different human tumor cell lines, subjected in vitro to hypotonic exposure for 1 to 10 minutes. Only the carcinoid, multiple myeloma, leiomyosarcoma cell lines, and normal lymphocytes were destroyed by the treatment. Although breast, ovarian, gastric, bladder, and melanoma cell lines were damaged to varying degrees, viable cells persisted in all cases. These data suggest that hypotonic shock is not an effective method to kill human tumor cells.

Autoradiography↗

PubMedDate not supplied

Two-step simultaneous distillation and solvent extraction for isolation both free and bound aroma in tobacco.

In this investigation, a novel two-step simultaneous distillation and solvent extraction (two-step SDE) method was developed to isolate both free and bound aroma in tobacco. Firstly, free aroma were extracted into dichloromethane by SDE for 4 h with SDE sample solution at pH 5.5. Then the SDE sample solution was adjusted to pH 2.5, bound aroma were hydrolyzed, and released as free aroma extracted by fresh dichloromethane. Following, both the free and bound aroma were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The whole isolation procedure of both free and bound aroma was carried out in one SDE apparatus and using one same sample. Especially, the procedure of isolation of bound aroma was greatly simplified. To apply and validate the proposed two-step SDE method, a traditional method were also used to isolate the bound aroma. The total bound aroma obtained by the proposed two-step SDE method and the traditional method were 119.83 mg kg(-1) and 88.9 mg kg(-1), respectively. For isolation of bound aroma, the proposed two-step SDE method was of better extraction recovery, less labourious, solvent and time consuming than the traditional method.

Chromatography, Gas↗

PubMed1988

Identification by methane chemical ionization gas chromatography/mass spectrometry of the products obtained by steam distillation and aqueous acid extraction of commercial Piper methysticum.

Bornyl cinnamate has been identified as a constituent of kava resin and of the steam distillate of Piper methysticum. 5-Hydroxydihydrokawain was identified in commercial samples of P. methysticum originating from Vanuatu provided an initial aqueous extraction was employed. Commercial preparations, and fresh samples of the root of this plant from Fiji, lacked this compound. Two previously described N-cinnamoyl pyrrolidine alkaloids were also observed along with stigmasterol in kava resin from Fiji and Vanuatu. The products derived from aqueous 2 M hydrochloric acid extraction of P. methysticum were determined from methane chemical ionization gas chromatography/mass spectrometry analysis which identified a series of hydroxylated compounds (15a-d) derived from formal decarbonylation of the parent kava lactones. The products (13a-c) of dehydration of these compounds were also observed. The efficiency of kava resin extraction from plant material by water (the traditional method of preparation of the kava beverage) was typically 5-10% of that recovered by direct extraction with an organic solvent.

Fiji↗

PubMed2002

Nonlinearity in optical resolution via distillation applying mixtures of resolving agents.

During an optical resolution it is the resolving agent that has the strongest influence on the outcome of the process. Applying a mixture of resolving agents can result either in antagonism or in synergy. We found that using mixtures of tartaric acid and its derivatives chiral selectivity is at least the same, but in several cases markedly better (synergistic effect), than the sum of the effect of the individual resolving agents. Thus, the "Dutch method," reported for the crystallization method, also works for distillation. A calculation method is applied for measuring the synergistic effect. Interestingly, an individually inactive resolving agent can be a useful contributor to the mixture of the resolving agents.

Journal Article↗

PubMed2001

Solvent-free optical resolution of N-methylamphetamine by distillation after partial diastereoisomeric salt formation.

Solvent-free optical resolution of N-methylamphetamine was developed by distillation after partial diastereoisomeric salt formation. From the 18 chiral acids tested by this method, five provide by this method resolution: O,O'-dibenzoyltartaric acid, O,O'-di-p-toluoyltartaric acid, 6-methoxy-alpha-methyl-2-naphthaleneacetic acid (Naproxen), the cis-permetrinic acid, and the 2-phenoxypropionic acid. Among them the O,O'-dibenzoyltartaric acid in water-free form provided the more effective resolution. The efficiency of this resolution S = 0.74 is in the range of the industrial-scale resolutions and not worse than the efficiency achieved by optical resolution via fractional crystallization.

Journal Article↗

PubMed1993

Use of freeze-substitution and molecular distillation drying in the preparation of Dunaliella parva for ion localization studies by X-ray microanalysis.

The determination of ion concentrations within cells and sub-cellular compartments remains a difficult procedure, as the volumes to be analyzed are rather small. X-ray microanalysis is sufficiently sensitive, and has adequate resolution, to measure these concentrations. The major difficulties are related to the preparation of material for analysis. We have compared the measurement of sodium, potassium, and chloride contents in a salt tolerant unicellular alga, Dunaliella parva, following either freeze-substitution (using two different resins) or molecular distillation drying. All three procedures gave similar results: after freeze substitution, ion contents were marginally (but not significantly) higher following embedding in Nanoplast MUV 116 resin than in Spurr resin. Since the Nanoplast can be polymerised at low temperatures, it has advantages over the Spurr resin.

Chlorides↗

PubMed2005

Some advances in the knowledge of grape, wine and distillates chemistry as achieved by mass spectrometry.

Mass spectrometry plays a very important role in acquiring knowledge of the chemistry of grape and its derivative products. By liquid mass spectrometry, anthocyanins of grape were studied, and in hybrid grape extracts, delphinidin, cyanidin, petunidin and malvidin 3-O-(6-O-p-coumaroyl)-5-O-diglucosides were found. A semiquantitative procedure to estimate the amounts and percentages of monoglucoside and diglucoside anthocyanins without chromatography was developed. By gas chromatography mass spectrometry (GC/MS), aroma compounds of grape, wine and the distillate Italian grappa were studied, and molecular structures characterized. The representative aroma profile of Muscat grape was characterized by 23 terpenols, present in both free and bonded form, and direct correlation between aroma and genetic profile permitted to distinguish between different Muscat grape varieties. Aroma of Italian grappa resulted from and was characterized by several compounds linked to the grape variety, such as vitispiranes, terpenols, ethyl cinnamate, salicylic esters, benzaldehyde and farnesol. Synthesis of O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBOA) derivatives and GC/MS analysis resulted in a sensitive and selective method to study carbonyl compounds at the low levels occurring in wine.

Food Technology↗

PubMed1991

Equivalency of hydrochloric acid and distilled water extraction media for determining residual ethylene oxide in medical devices.

An alternate method for determining residual ethylene oxide (EtO) in medical devices was compared with the aqueous extraction method suggested by the Association for the Advancement of Medical Instrumentation (AAMI). Residual EtO was extracted from EtO-sterilized samples of acrylic polymer (XT250-301 glass-tinted formulation) in pellet form by immersion in 1 M HCl at 37 +/- 2 degrees C (alternate method) or immersion in distilled water (AAMI method). The EtO residuals in the extracts were determined using gas chromatography and were statistically compared using a two-sample t test. Results obtained using the alternative method agreed within 10% of those obtained using the AAMI method.

Chromatography, Gas↗

PubMed1993

Nedocromil sodium vs. sodium cromoglycate pressurized aerosol in the prevention of bronchoconstriction induced by ultrasonic nebulized distilled water in asthmatic children.

To compare the effectiveness of nedocromil sodium (NS) and sodium cromoglycate (SCG), administered by metered dose inhaler (MDI) with a 700 mL holding chamber (Fisonair Fisons UK) in preventing bronchoconstriction induced by inhalation of ultrasonically nebulized distilled water (UNDW), 12 asthmatic children were studied in a randomized, double-blind, placebo-controlled, intrapatient study. Following a baseline challenge with UNDW, the protective effect of NS, SCG, or placebo was evaluated in each subject. Cumulative doses of delivered nebulized water producing a 20% fall in forced expiratory volume in 1 sec (PD20 UNDW) was measured. Mean (+/- SD) PD20 UNDW was 4.83 (+/- 4.84), 10.16 (+/- 7.05), 1.58 (+/- 0.5), and 15.93 (+/- 0.23) respectively, for baseline, and placebo, SCG, and NS-treated groups. A significant (P < 0.05) protection from UNDW induced bronchoconstriction by NS was observed in comparison with placebo, while no such effect was evident when the children were treated with SCG.

Adolescent↗

PubMed2003

Essential oil composition and antifungal activity of Foeniculum vulgare Mill obtained by different distillation conditions.

The influence of different hydrodistillation conditions was evaluated from the standpoint of essential oil yield, chemical composition and antifungal activity from seeds of Foeniculum vulgare Mill. Three hydrodistillation conditions were considered. The main constituents of the oils were: (E)-anethole (72.27%-74.18%), fenchone (11.32%-16.35%) and methyl chavicol (3.78%-5.29%). The method of distillation significantly effected the essential oil yield and quantitative composition, although the antifungal activity of the oils against some fungi was only slightly altered.

Antifungal Agents↗

PubMed1995

Studies on the tumor initiation/promotion potential of six middle distillates (MDs) in mouse skin.

Six middle distillates (MDs) were tested for tumor initiating/promoting activity after application to the skin of 30 male CD-1 (ICR) BR mice per group. As the control, 7,12-dimethylbenz[a]-anthracene (DMBA) was used for initiation followed by 12-O-tetradecanoylphorbol-13-acetate (TPA) for promotion. For assessing the tumor-initiating activity, 50 microliters of neat MDs was administered for 5 days with subsequent TPA promotion. In the promotion bioassay, after DMBA initiation 50 microliters of the neat MDs was administered twice weekly until Week 28. For the examination of complete carcinogenic activity, one MD was given without DMBA initiation. Hyperkeratosis, hyperplasia, and dermal inflammation, occurring during the initiation with the MDs, were completely reversible during the 2-week treatment-free period after initiation. Similar skin findings were observed during promotion with the MDs. Regarding the number of affected animals and the severity of the response, TPA was more irritating than the MDs. The initiation study revealed skin tumors for the DMBA/TPA control (30/30), MD 57,389 (14/30), MD 57,396 (5/30), MD 57,383 (4/30) and MD 57,324 (2/30). The promotion study revealed tumor induction by MDs 57,389 (9/30), 57,324 (1/30), 57,393 (1/30), and 57,396 (1/30). Two of 30 animals treated with MD 57,389 developed tumors without DMBA initiation thus indicating that it also is a complete carcinogen. MD 57,399 caused neither initiating nor promoting effects. The tumors observed were diagnosed histopathologically predominantly as squamous cell papillomas.(ABSTRACT TRUNCATED AT 250 WORDS)

9,10-Dimethyl-1,2-benzanthracene↗

PubMed1996

Systemic and developmental toxicity of dermally applied distillate aromatic extract in rats.

Distillate aromatic extract (DAE) was evaluated for subchronic and developmental toxicity. In the subchronic study, undiluted DAE was applied on the shaved backs of male and female rats at dose levels of 0, 30, 125, 500, and 1250 mg/kg for 13 weeks, 5 days per week. Exposure sites were not covered. In the developmental toxicity study, DAE was similarly applied, but to pregnant rats at dose levels of 0, 8, 30, and 125 mg/kg on Gestation Days 0-19, 500 mg/kg on Gestation Days 0-16, and 1000 mg/kg on Gestation Days 10-12. Evidence of toxicity observed in the subchronic study included death, decreased body weights, aberrant serum chemistry and hematology values, altered organ weights, and histopathologic changes in a variety of organs. Regardless of the length of the exposure period, DAE was toxic to the developing conceptus. Evidence of developmental toxicity observed included increased resorptions and reduced fetal body weights. Cleft palate and ossification delays were observed in fetuses exposed in utero to DAE on Gestation Days 10-12, but not when exposure spanned all (Gestation Days 0-19) or most (Gestation Days 0-16) of gestation.

Animals↗

PubMed1994

The protective effects of ipratropium bromide and terbutaline on distilled water-induced bronchoconstriction.

In a randomized, double-blind, placebo-controlled study, we investigated the protective effects of ipratropium bromide 160 micrograms and 320 micrograms and terbutaline 500 micrograms on ultrasonically nebulized distilled water (UNDW)-induced bronchoconstriction in nine stable asthmatic patients. Both drugs caused a significant increase (P < 0.001) in baseline FEV1 with no significant differences between the drugs or both doses of ipratropium bromide. Pre-inhalation of ipratropium bromide 320 micrograms and terbutaline 500 micrograms inhibited UNDW-induced bronchoconstriction (P < 0.01), whereas ipratropium bromide 160 micrograms had no protective effect. The protective effects of ipratropium bromide showed a large interindividual variation. There was no correlation between the increase in baseline FEV1 and PD20 UNDW, indicating that the protective effect on UNDW-induced bronchoconstriction is not dependent on the bronchodilation induced by terbutaline and ipratropium bromide. It also appears that the UNDW-induced bronchoconstriction is at least partly vagally mediated.

Administration, Inhalation↗

PubMed1998

A comprehensive evaluation of the mechanism of skin tumorigenesis by straight-run and cracked petroleum middle distillates.

The role of skin irritation and other factors on the tumorigenic activity of petroleum middle distillates (PMDs) in mice was examined in a comprehensive research program. The program culminated in a 2-year dermal carcinogenicity study which compared the effects of equal weekly doses of irritating and nonirritating PMDs. Modified Ames mutagenicity studies and three- to seven-ring polycyclic aromatic compound (PAC) analyses indicated that the mutagenic activity of PMDs was correlated to PAC content. In subchronic and subacute studies, PMDs produced marked skin irritation which was ameliorated if the test samples were diluted in mineral oil. The reduction in irritation level was not a result of reduced dermal absorption. Straight-run kerosine (SRK), straight-run gas oil (SRGO), and catalytically cracked light cycle oil (LCO) were evaluated in the dermal carcinogenicity study. Test materials were applied either undiluted (2x/week) or as 28.5% (7x/week) or 50% (4x/week) concentrations in mineral oil for a total weekly dose of 100 microliters PMD per animal. All three materials produced moderate to marked skin irritation and increased tumor frequency when applied undiluted. When diluted, the irritant effects of SRK and SRGO, which contain low levels of PACs, were ameliorated, and there were no significant increases in tumors relative to controls. LCO, containing 8.7% three- to seven-ring PACs, increased tumor frequency when diluted, even when skin irritation was limited. These data indicate that the tumorigenic activity of straight-run MDs is likely a consequence of a nongenotoxic process, associated with frequent cell damage and repair. PMDs which contain low levels of three- to seven-ring PACs are unlikely to cause tumors in the absence of prolonged skin irritation. In addition, genotoxic mechanisms may also contribute to tumor formation for other PMDs containing higher levels of PACs, e.g., products blended with cracked stocks.

Animals↗