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PubMedDate not supplied

Determination of crude protein in animal feed, forage, grain, and oilseeds by using block digestion with a copper catalyst and steam distillation into boric acid: collaborative study.

A collaborative study was conducted to evaluate the repeatability and reproducibility of an extension of AOAC Official Method 991.20, Nitrogen (Crude) in Milk, to animal feed, forage (plant tissue), grain, and oilseed materials. Test portions are digested in an aluminum block at 420 degrees C in sulfuric acid with potassium sulfate and a copper catalyst. Digests are cooled and diluted, and concentrated sodium hydroxide is added to neutralize the acid and make the digest basic; the liberated ammonia is distilled by using steam distillation. The liberated ammonia is trapped in a weak boric acid solution and titrated with a stronger standardized acid, hydrochloric acid; colorimetric endpoint detection is used. Fourteen blind samples were sent to 13 collaborators in the United States, Denmark, Sweden, Germany, and the United Kingdom. Recoveries of nitrogen from lysine, tryptophan, and acetanilide were 86.8, 98.8, and 100.1%, respectively. The within-laboratory relative standard deviation (RSDr, repeatability) ranged from 0.40 to 2.38% for crude protein. The among-laboratories (including within-) relative standard deviation (RSD(R), reproducibility) ranged from 0.44 to 2.38%. It is recommended that the method be adopted First Action by AOAC INTERNATIONAL. A lower concentration (1% H3BO3) of trapping solution was compared with the concentration specified in the original protocol (4% H3BO3) and was found comparable for use in an automatic titration system in which titration begins automatically as soon as distillation starts. The Study Directors recommend that 1% H3BO3 as an optional alternative to 4% boric acid trapping solution be allowed for automatic titrators that titrate throughout the distillation.

Animal Feed↗

PubMed2002

Reducing bacterial counts in dental unit waterlines: tap water versus distilled water.

BACKGROUND: The maximum recommended level of microbial contamination of water from dental unit waterlines (DUWL) is 200 colony-forming units per milliliter (CFU/mL). This article addresses the importance of water selection in achieving that standard. METHODS: Microbial contamination in water samples from 75 new dental units, with a closed-circuit water system, were compared using combinations of tap water and sterile distilled water with and without two chemical disinfectants (bleach and 0.12% chlorhexidine gluconate, Bio2000) over a six-week period. Baseline tap water samples were collected and tested initially. RESULTS: The microbial plate counts of seven tap water specimens (controls) ranged from 4 to 95 CFU/mL. These results were well below both the 500 CFU/mL standard for public drinking water and the 200 CFU/mL goal for dental treatment water. However, when passed through dental units, no significant bacterial reduction was achieved for samples of tap water (Group 1), tap water treated with bleach (Group 2), or tap water treated with Bio2000 (Group 4). Only water samples from dental units using Bio2000 alone (Group 3) or a combination of sterile, distilled water with Bio2000 (Group 5) met or exceeded the 200 CFU/mL standard. CONCLUSIONS: Using tap water alone or tap water with bleach did not improve water quality. However, the American Dental Association (ADA) standard for reduced microbial contamination of dental unit waterlines was met using Bio2000 and distilled water treated with Bio2000. CLINICAL SIGNIFICANCE: The ADA standard of 200 CFU/mL was achieved using a closed water system and distilled water treated with Bio2000. Using 100% Bio2000 is also effective, but more costly.

Analysis of Variance↗

PubMed1992

Effect of inhaled beclomethasone and nedocromil sodium on bronchial hyperresponsiveness to histamine and distilled water.

In a randomized, cross-over study we compared the effects of inhaled nedocromil sodium, 4 mg q.i.d., with inhaled beclomethasone dipropionate, 200 micrograms q.i.d. in 23 atopic asthmatic patients. After a 3 week single-blind placebo period, regarded as the baseline, and after 4 and 8 weeks of active treatment, drug effects were assessed with regard to bronchial hyperresponsiveness to histamine and distilled water, lung function and beta 2-agonist use. After 4 and 8 weeks of treatment, nedocromil sodium reduced the histamine responsiveness (p < 0.005 and p < 0.0005), but not the distilled water responsiveness, and did not improve lung function and peakflow measurements compared to baseline. After 4 and 8 weeks of treatment, beclomethasone caused a significant increase in lung function (p < 0.005) and decrease in bronchial hyperresponsiveness to histamine (p < 0.0005) and distilled water (p < 0.0005) as compared to baseline. beta 2-agonist use was significantly diminished after an 8 week treatment with beclomethasone, whereas nedocromil sodium had no effect. Treatment with beclomethasone was superior to treatment with nedocromil sodium with regard to bronchial hyperresponsiveness to histamine and distilled water (p < 0.0005 and p < 0.005), lung function (p = 0.003), peakflow measurements (p < 0.05) and beta 2-agonist use (p < 0.005).

Administration, Inhalation↗

PubMed2003

[Comparative assessment of the human cell viability ex vivo in Hanks solutions in distilled and Penta water].

Assessment of human colon and lung mucosa cell viability was performed in Hanks salt media prepared separately with distilled and patented Penta water. The cell viability in the suspension was estimated by fluorescence intensity of propidium iodide, a DNA specific dye, that is an indicator of DNA structure intactness or damage. The experiments were conducted with the flow cytometry technique. The histogram analysis showed that 2-hour incubation of the cells in Hanks salt medium prepared with distilled water resulted in an increase of the number of the apoptotic cells with a respective decrease of the number of the intact cells (approximately 2- and 4-fold in the suspensions of the colon and lung mucosa cells respectively). A similar experiment with Hanks salt medium prepared with Penta water resulted in a less marked increase of the viability of the apoptotic cells that did not exceed 20 and 50% for the colon and lung mucosa cells respectively. The findings showed that viability of the cells ex vivo was significantly higher when Penta water was used as a solvent for preparing Hanks salt media as compared to distilled water. The result is important for ex vivo experiments since maximum preservation of the DNA structure minimizes the number of possible experimental inaccurate and consequently erroneous conclusions. Furthermore, the fact of pathologic process inhibition in cells isolated from various human tissues in Penta-based salt media is in favour of using Penta water as a solvent for nutritional ingredients in ex vivo maintenance of human tissues for transplantation as compared to distilled water.

Cell Survival↗

PubMed2004

Aromatic content in medium range distillate products--Part I: an examination of various liquids.

Classification of ignitable liquids in accordance with voluntary consensus-based standards published by ASTM International has become increasingly specific, relying upon both the chemical composition and the boiling point range of submitted ignitable liquids. This classification system includes among others, specific classes for distillates and dearomatized distillates. In this study, a variety of medium-range ignitable liquids were analyzed by gas chromatography-mass spectrometry. Several methods of data analysis were utilized to examine the relative aliphatic and aromatic contents in these liquids. Results show that commercially available products in the medium range exhibit a broad range of compositions with respect to the relative proportion of aliphatic and aromatic compounds and that some liquids may not be easily classified. This study demonstrates the importance of examining the proportion of aliphatics:aromatics for classifying such liquids and suggests guidelines for differentiating medium range distillates, dearomatized distillates, and blended products.

Journal Article↗

PubMed2004

[Distilled water pleurodesis for two breast cancer patients suffering from carcinomatous pleurisy].

Pleural effusion of carcinomatous pleurisy is relatively common and a significant problem in recurrent breast cancer patients. It's very important to control it to keep a good quality of life for those patients. Two recurrent breast cancer patients, suffering from carcinomatous pleurisy and dyspnea due to pleural effusion, were treated with distilled water. As they have been treated with many kinds of hormonal therapy or chemotherapy for their several distant metastases, the performance status of these therapies has not been good. After one or two distilled water pleurodesis, pleural effusion was well controlled and dyspnea had disappeared. No adverse events, such as high fever and chest pain concerning this distilled water therapy were experienced. Taking its efficacy and a rarity of adverse events, distilled water plerodesis is a useful treatment for pleural effusion of carcinomatous pleurisy.

Breast Neoplasms↗

PubMed2004

[Study on purification technology of patchouly oil with molecular distillation].

OBJECTIVE: To establish an advanced purification techniques of the essential oils obtained from Pogostemon cablin. METHOD: Molecular distillation (MD) was applied. RESULT: Four distillates were obtained, chemical constituents of which were analyzed with GC-MS. Compared with those in original oils, the contents of active compounds (patchouli alcohol and pogostone) rose by 27%-47% in the distillates II and III. CONCLUSION: Molecular distillation (MD) effectively raises the contents of patchouli alcohol and pogostone. The work is of great economic and scientific significance for the industrialization of P. cablin and the discovery of new drugs.

Gas Chromatography-Mass Spectrometry↗

PubMed2005

Effect of an aqueous distillate of Origanum onites L. on isolated rat fundus, duodenum and ileum: evidence for the role of oxygenated monoterpenes.

The aqueous distillate of Origanum onites L. (Labiatae) was reported to have various ethnomedical uses including effects on the gastrointestinal tract. The effects of three different doses (0.1, 0.2 and 0.4 mL) of the aqueous distillate of Origanum onites on isolated rat fundus, duodenum and ileum against acetylcholine induced contractions were investigated in this study. The aqueous distillate inhibited contractions in a dose dependent manner. Inhibitions were lowest on fundus. Carvacrol, being the major compound of the test substance, did not inhibit acetylcholine induced contractions of the isolated rat fundus, indicating the presence of other active principles including menthane diols. As being one of the first pharmacological studies on aqueous distillates, a possible pharmacological activity of cis-p-menth-4-ene-1,2-diol and 3,7-dimethyl-1-octen-3,7-diol is proposed in this study.

Acetylcholine↗

PubMed2006

Optimization of distilled monoglycerides production.

Monoglycerides (MG) are emulsifiers widely used in food and pharmaceutical industries. Current industrial processes for MG production consist of the interesterification of triglycerides with glycerol (GL), in the presence of inorganic catalysts at high temperatures (> 200 degrees C). This reaction is known as glycerolysis and produces a mixture of approx 50% of MG. This level of concentration is suitable for many applications, although, for some specific uses like margarine, shortening, icing, and cream filling, require distilled MGs, which are purified MG (min. 90%) obtained by the molecular distillation process. Therefore, in this work, a 23 factorial design was employed to evaluate the effects of reaction parameters in the MG content after the interesterification reaction of refined soybean oil with GL in the presence of sodium hydroxide as catalyst. After that, the MG content in the reaction product was enhanced through the molecular distillation process in order to obtain distilled MG.

Bioreactors↗

PubMed1988

The dangers of distilled water in contact lens maintenance.

The reports of serious corneal infection associated with hydrogel lens wear prompted us to explore the level of sterility of the distilled water used by lens wearers in our practice. Fifty patients supplied samples of their partially-used distilled water for testing. Of the samples, 12% were found to be contaminated. Five samples of previously unopened distilled water were tested and no growth was found. We recommend that patients do not use distilled water for the care of hydrogel contact lenses. Rather, sterile unit dose or multi-dose (aerosol) nonpreserved, or preserved salines can be used.

Bacteria↗

PubMed1986

Legionnaires' disease caused by Legionella dumoffii in distilled water.

Five cases of Legionnaires' disease caused by Legionella dumoffii were identified within an 11-month period in a hospital in the Quebec City area. In four cases bacterial isolates were obtained from clinical specimens, and in one case seroconversion was demonstrated. All the patients had been admitted to hospital within 10 days before diagnosis. Two of the patients were immunosuppressed children. Only 1 of the 40 hot water samples from the hospital yielded L. dumoffii; however, 6 of 11 distilled water samples contained the bacterium. All the patients had been exposed to distilled water, four through respiratory therapy equipment and one through a room humidifier. Following the use of sterile distilled water in the apparatus, no further cases were identified. This is the first reported outbreak of Legionnaires' disease caused by L. dumoffii, and it is the first time that nosocomial legionellosis has been linked to contaminated distilled water in Canada.

Adult↗

PubMedDate not supplied

Determination of several halogenated fumigants in cereal products by steam distillation and capillary gas chromatography with electron capture detection.

A steam distillation procedure is described for the determination of ethylene dibromide (EDB), ethylene dichloride (EDC), and carbon tetrachloride (CT) in flour, flour-based mixes, baked cakes, breakfast cereals, and citrus fruits. A representative sample is steam distilled using a modified Garman steam distillation apparatus, the steam and volatile components are condensed, and the condensate is partitioned with hexane (EDB) or pentane (EDC and CT). The solvent extract is then injected on-column and analyzed by using a 15 m X 0.32 mm 1.0 micron DB-1701 fused-silica capillary column at 50 degrees C for EDB or a 30 m X 0.25 mm 1.0 micron DB-5 column at 35 degrees C for EDC and CT. For routine EDB determinations as low as 10 ppb, 2 g flour, flour-based mix, or breakfast cereal is distilled and partitioned into 10 mL hexane. For enhanced sensitivity, up to 10 g dry sample can be concentrated into 1 mL hexane, for detection as low as 0.1 ppb (10% FSD, 2.0 pg). Recoveries from flour spiked with 100, 5, and 0.5 ppb EDB were 98.9, 95.1, and 117%, respectively. Coefficients of variation for marketplace flour samples found to contain EDB at 122, 6.0, and 1.2 ppb were 4.6, 6.9, and 3.6%, respectively, and for baby cereal at 0.22 ppb, 4.5%. Recoveries for EDC and CT from flour spiked at 46, 94, and 140 ppb were 61, 73, and 72%, and 96, 95, and 87%, respectively. Coefficients of variation were 10.0, 7.8, and 4.8, and 8.0, 3.2, and 8.4%, respectively.

Chromatography, Gas↗

PubMed1983

Change in Bmax and Kd for [3H]flunitrazepam observed in the course washing rat brain tissue with distilled water.

A method for the removal of an endogenous inhibitor(s) of benzodiazepine receptor binding (extraction in distilled water at 20 degrees) was used to evaluate the possible influence of this inhibitor(s) on the affinity of the benzodiazepine receptor in vivo. The results indicate that the presence of an inhibitor(s) in the concentration which exists in the rat brain leads to a 30-fold increase in the Kd value as compared with the results obtained in vitro. The endogenous inhibitor(s) appeared to be a thermostable, proteinase K-resistant substance(s) with Mr between 500 and 10,000 daltons. Repeated washings of the brain tissue with distilled water were accompanied by a decrease in the Bmax for [3H]flunitrazepam. The [3H]flunitrazepam binding sites with Kd = 1.7 nM and Bmax = 61 fmoles/mg of protein were found in the supernatant collected after the second and third washings in distilled water. The presence of diazepam and the benzodiazepine antagonist Ro 15-1788 prevented in a dose-dependent manner the decrease in the Bmax value for [3H]flunitrazepam during the tissue washing with distilled water.

Animals↗

PubMed1984

[Distillation of used liquid scintillation cocktail and the possibility of re-utilization of the recovered solvent].

Liquid(toluene and dioxane)scintillation cocktail containing [methyl-3H]thymidine as a radioactive material was distilled by a rotary evaporator after storage for 0 to 12 months. The solvent obtained by distillation was then purified by several treatments, and the 3H-concentration in the solvent after each treatment was determined accurately. The 3H-concentration in the rotary evaporator-distillate of the cocktails reached about 0.2% of that of the original scintillation cocktails when they were stored for 12 months. But these radioactive materials could be removed completely from each solvent by several refining treatments: washing with water followed by dehydration with molecular sieves in case of toluene scintillation cocktail, and desiccation by adding excess amount of KOH in case of dioxane scintillation cocktail. It was concluded that the distillation followed by several simple refining treatments was useful to regenerate the refined solvent available for the preparation of liquid scintillation cocktail and also as a preliminary step to dispose of the waste scintillation cocktail.

Radioactive Waste↗

PubMed1995

Induction of short-term biomarkers of tumor promotion in skin of CD-1 mice by petroleum middle distillates: preliminary observations.

The induction of sustained epidermal hyperplasia in mouse skin has been shown to be a reliable predictor of tumor promoting activity for chemicals as diverse as phorbol esters, anthralins, n-dodecane and organic peroxides (DiGiovanni, 1992). The results contained herein demonstrate that API 81-07 and API 81-10, petroleum middle distillates that exhibit tumor promoting activity in mouse skin, induce epidermal hyperplasia and ODC activity. Other petroleum middle distillates (odorless light petroleum hydrocarbons, a light vacuum distillate, and a mineral seal oil) were also shown to share these activities. It should be emphasized that the relevance of these observations to human skin remains unresolved; however, the availability of these short-term biomarkers offers the opportunity to address the issue by performing comparative investigations on the effects of petroleum middle distillates on human skin xenografted to athymic (nude) mice. Such studies are being initiated.

Alkanes↗

PubMed2004

Tocopherol composition of deodorization distillates and their antioxidative activity.

During the last stage of plant oil refining, deodorization distillates containing very important biological substances such as tocopherols, sterols, terpenoids or hydrocarbons are formed as a by-products. This study aimed at evaluating the content and antioxidant capacity of tocopherol concentrates from deodorization distillates obtained after the refining of rapeseed, soybean and sunflower oil. The majority of the matrix substances were eliminated from deodorization distillates by freezing with an acetone solution at -70 degrees C. The tocopherol concentrates obtained in this way contained approximately fivefold more tocopherols than the quantity in condensates after deodorization. Antioxidant activity was investigated by observing the peroxide value at 25 degrees C and using the Oxidograph test. The test medium was lard enriched with the tocopherol concentrates of the three plant oils versus single, synthetic alpha-, gamma- and delta-tocopherols (-T), which served for comparison. In these model systems, all investigated tocopherol concentrates exhibited antioxidant capacity. Their antioxidant effect was significantly lower than that of single delta-T and gamma-T, but significantly higher than alpha-T. The results prove that natural tocopherol concentrates obtained from plant oils are valuable food antioxidants and they also increase the biological and nutritional value of food especially when administered to animal fats or food of animal origin. Tocopherol concentrates can fully replace synthetic antioxidants that have been used thus far.

Antioxidants↗

PubMed2003

Isolation of volatile oil from thyme (Thymbra spicata) by steam distillation.

The effects of steam flow rate (1.03 and 0.64 L/h), distillation time, and particle size (0.50, 1.00, 2.05 mm) of Thymbra spicata on essential oil yield and sequence of extraction of compounds were studied. A logarithmic model fitted well to experimental data. The composition of the essential oil obtained by steam distillation was investigated for whole leaves only since the grinding had an adverse effect on yield. The oil obtained was very rich with respect to its carvacrol content. For both steam flow rates, oxygenated monoterpenes were recovered the most rapidly. Using whole leaves (2.05 mm) and a higher steam flow rate (1.03 L/h) for 75 min of distillation was chosen as the optimum which gives the lowest amount of monoterpene hydrocarbons, the complete recovery of oxygenated compounds, and the highest yield in a shorter time. Yield was 1.57% at this optimum condition. The oil was composed of 53.1% oxygenated compounds, 25.7% monoterpene hydrocarbons, 4.4% sesquiterpenes, and 14.1% p-cymene.

Chromatography, Gas↗

PubMed1984

Mutagenicity and chemical characterization of two petroleum distillates.

To investigate if the Salmonella/microsome assay could reliably screen complex petroleum samples for their carcinogenic potential, two high boiling (700-1070 degrees F) petroleum distillates with known activity in a dermal carcinogenesis bioassay were fully characterized with respect to their hydrocarbon composition and polynuclear aromatic hydrocarbon (PNA) content and assayed for mutagenic activity. Mutagenicity assays were also carried out on the aromatic hydrocarbon aggregates separated from these oils by adsorption chromatography. The composition of the distillates differed substantially, and reflected the fact that they were derived from crude oils that were extremely divergent in hydrocarbon character. Both the distillate and aromatic samples consistently induced a very slight increase in revertant TA98 and TA100 colonies; however, an increase of 2-4-fold over background was observed when the S-9 concentration was increased 5-10 times that of the standard assay. The maximal response was less than that expected from the samples' known PNA content and observed potency in the dermal carcinogenesis bioassay. In the Salmonella/microsome assay, all samples inhibited the mutagenic activity of added benzo[a]pyrene. Discordance between the magnitude of the samples' mutagenic activity and their known PNA content may be related to direct or indirect inhibition of sample PNAs by other components of the complex petroleum fractions. Observed inhibitory effects support the use of elevated S-9 concentration in the in vitro assays assessing the carcinogenic potential of petroleum-derived materials.

Animals↗