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PubMed2001

Improved determination of tributyl phosphate degradation products (mono- and dibutyl phosphates) by ion chromatography.

Tributyl phosphate (TBP) is a very important compound in the nuclear industry, particularly in the area of nuclear fuel reprocessing. This compound is used in the PUREX (plutonium and uranium refining extraction) process which consists of the extraction of uranium and plutonium from an aqueous nitric acid phase, for the purpose of recycling. But TBP may be degraded to dibutyl phosphate (DBP) and monobutyl phosphate (MBP) by dealkylation of one or two butoxy groups, respectively. We have compared and evaluated the capacity of two resins manufactured by Dionex (AS11 and AS5A) in the separation and measurement of these two degradation products. AS11 generates two interferences: nitrite/DBP and carbonate/MBP. The first one is the most serious. So, we have developed a method for oxidising nitrite ions to nitrate ions which have no trouble over the measurement. The second resin tested, AS5A, allows a very efficient separation between DBP and NO2- ions and a good separation between MBP and CO3(2-) in comparison with the AS11. The detection limits for the AS5A column are 0.13 microM for MBP and 0.71 microM for DBP (injection loop=50 microl).

Calibration↗
PubMed2000

Albumin purification from human placenta.

Albumin is the human protein used mainly for therapeutic purposes. Besides the traditionally used plasma, blood from placenta is an alternative source for albumin purification. We describe here an industrial process for purification of albumin from human placenta. The proposed albumin-purification process, for 50 kg of placentas, comprises: (i) extraction of haemolysed blood with saline and solid/liquid separation by basket centrifugation; (ii) selective precipitation of haemoglobin by ethanol/chloroform and precipitate removal by filtration in a press filter; (iii) concentration/diafiltration of the filtrate in a 30 kDa cross-flow ultrafiltration (CFUF) membrane; (iv) thermo-coagulation at 70 degrees C with sodium octanoate/EDTA; (v) treatment with activated charcoal at pH 3; (vi) concentration/diafiltration of the filtrate in a 30 kDa CFUF membrane; (vii) anion-exchange chromatography Q-Sepharose; (viii) hydrophobic-interaction chromatography with phenyl-Sepharose; and (ix) conditioning and pasteurization. The process yields an average of 4.5 g of albumin/kg of placenta with a purity of 97.1% and A(403) of 0.05 (1% protein). The final product passes pyrogen and toxicity tests in vivo and it does not contain polymers or aggregates, even after the accelerated stability test, as judged by gel filtration, as required by the Brazilian Pharmacopoeia.

Biotechnology↗
PubMed1995

Cardiac frequency throughout a working shift in coal miners.

Despite the ever-increasing mechanization of industrial activities, coal mining still remains a physically demanding occupation as it is not always possible to extensively mechanize the extraction process. To estimate the physical effort necessary to sustain coal mining activities in a poorly-mechanized mine, cardiac frequency (fc) was measured throughout the working shift with a Sport-Tester PE3000 (Polar Electro OY, Finland) in a representative sample of 73 Asturian miners engaged in a full spectrum of underground work. The mean +/- SD of the overall fc values measured in miners working at the coal face (Group 1, 33 subjects, mean age 32.7 years, age range 21-48 years) was 106.5 +/- 18.2 beats.min-1. In other miners (Group 2, 40 subjects, mean age 34.6 years, age range 23-48 years) corresponding figures were 103.1 +/- 17.7 beats.min-1 (p < 0.05). Subjects' average working shift fc (beats.min-1) was not related to age, measured (treadmill) VO2 max nor VO2 max.kg body weight-1, while average working-shift fc (%fc max) was weakly related to age (r = 0.396, p < 0.05), VO2 max (r = -0.295, p < 0.05) and VO2 max.kg body weight-1 (r = -0.352, p < 0.05). Working-shift peak fc (beats.min-1) was negatively related to age (r = -0.334, p < 0.05). Our study has provided the distribution of the overall fc values likely to be found in subjects working in these poorly-mechanized mines. However, average working-shift fc differs considerably from subject to subject and is largely unpredictable.

Adult↗
PubMedDate not supplied

Effects of coffees before and after special treatment procedure on cell membrane potentials in stomach cells.

Coffee, one of the most excessively used beverages worldwide, commences the risk of gastroesophageal reflux (GER), which may lead to gastric ulcers and increase the risk of gastric cancer. Many attempts have been made by the coffee industry to diminish the irritating effect on mucosa by means of altering the extraction methods concerning gerbic acids and the roasting processes. This paper describes the effect of differently produced coffees involving two brands of Darboven and two brands of other coffee roasters. The aim of this study was to prove the results of gastric potential measurements we found in literature by using human AGS gastric epithelial cells (human adenocarcinoma). All four coffee extracts tested differentially affected the membrane resting potential of AGS cells. Coffees no. 1 and no. 2 depolarized the cells, presumably by increasing the cation entry into the cytosol. In marked contrast, coffee no. 4 hyperpolarizes the cells, possibly by H(+) extrusion and/or Cl(-) influx, suggesting that this coffee might increase acidity in the stomach, which might negatively affect the stomach, especially in people with gastroesophageal reflux symptoms. Overall, our data suggest that different roasting methods of coffees affect the membrane potentials of AGS stomach cells, resulting in increased influx of H+ possibly resulting in decreased stomach acidity and thus reducing GER. These results are in good accordance with clinical pharmacological results from potential difference measurements in healthy volunteers we found in the literature.

Adenocarcinoma↗
PubMed2003

Extraction of essential oil and pigments from Curcuma longa [L] by steam distillation and extraction with volatile solvents.

Curcuma longa [Linn] (turmeric), of the Zingiberaceae family, has a great importance in the food, textile, and pharmaceutical industries. The aim of this work was to identify the best processing conditions to maximize the yields of essential oil and pigments, as well as their content of ar-turmerone, (alpha and beta)-turmerone, and the curcuminoids, respectively. Autoclave pressure and distillation time were the variables studied for the steam distillation process. The highest yields of essential oil (0.46 wt %) and pigment (0.16 wt %)-expressed as curcumin, demethoxycurcumin, and bisdemethoxycurcumin-were obtained at a pressure of 1.0 x 10(5) Pa and a time of 2 h. On the other hand, with extraction by volatile solvents, the best yield of essential oil (5.49 wt %) was obtained when using 0.175, 0.124, 0.088 mm particles (Foust, A. S.; Wenzel, L. A.; Clump, C. W.; Maus, L.; Andersen, L. B. Princípios das Operações Unitárias; Editora Guanabara Dois S.A.: Rio de Janeiro, Brazil, 1982), at 40 degrees C, and 6 h of extraction. However, the best yield of pigment (7.98 wt %) was obtained under the same conditions, except for the temperature (30 degrees C).

Curcuma↗
PubMedDate not supplied

Use of supercritical fluid extraction as a method of cleaning anterior cruciate ligament prostheses: in vitro and in vivo validation.

The process of supercritical fluid extraction (SFE) using carbon dioxide as the mobile phase is finding increasing numbers of applications in a wide variety of industries for the extraction, separation, and cleaning of materials. This study assessed the usefulness of this approach in removing surface contaminants from a knitted polyester anterior cruciate ligament (ACL) prosthesis before packaging and sterilizing the product during manufacture. The physical, dimensional, and chemical properties of SFE treated compared with commercially scoured control samples were characterized using a number of textile test methods: electron spectroscopy for chemical analysis, Fourier transform infrared spectroscopy, differential scanning calorimetry, and solvent extraction analysis. The biocompatibility of the samples was measured in terms of their ability to generate CD18 integrin expression on activated human polymorphonuclear cells, and their inflammatory response when implanted for up to 30 days in the knee joint of rats. SFE treatment was successful in removing most of the nonpolar contaminants from the ACL prosthesis and reducing the amount of residuals to a commercially acceptable level. However, some nitrogen containing compounds and polar salts were not removed by the SFE process. The results from the biocompatibility tests demonstrated that the cleaner SFE treated prosthesis induced significantly lower CD18 expression than the scoured control fabric, and was also associated with a milder inflammatory response and a more rapid rate of healing during the 30 day animal trial. Another effect of SFE processing was to cause the polyester device to shrink and lose porosity because of yarn contraction and modification of the polymer's microcrystalline structure.

Animals↗
PubMed2004

Toxicological characterization of the new water cleaning product and its waste by-product.

Water extracts genotoxicity of the coagulant produced from industrial waste (red mud and waste base) and its waste mud remained after waste water treatment by the coagulation/flocculation process were studied. Tests were conducted in order to confirm nontoxicity of this new product prior to commercial production and usage and also to recommend a safe way for a handling and disposal of the remaining waste material. The toxicity investigation included (i) determining frequency of the cell survival, (ii) the Ames assays, (iii) micronucleus assay, and (iv) cell proliferation kinetics (expressed as mitotic index). These techniques were also employed in toxicity testing of the different concentrations of metal salts, zinc chloride, and lead nitrate in this case since these two elements were present in high concentrations in the waste water intended for the purification with the new coagulant. Mixture of metal salts in the concentrations that represent maximum allowed values for water extracts of technological waste was also tested. Two strains of Salmonella typhimurium, TA98, and TA100 were used for determining cytotoxicity and for the Ames test, while the cytogenetic investigations were performed on human peripheral blood lymphocytes. Water extracts of the coagulant and its waste mud did not induce a significant increase of the micronuclei in human peripheral blood lymphocytes. They also did not disturb lymphocyte proliferation kinetics in vitro. As regards lead nitrate it proved not to be cytotoxic on bacterial strains in the tested concentration range (1-100 mg/L), whereas zinc chloride showed cytotoxic effect for the concentrations above 25 mg/L. The Ames test results for the noncytotoxic concentrations of these metals were negative. Comparing to the negative control a significantly higher number of the micronuclei was determined after the treatment of the whole blood with 100 mg/L of zinc chloride, as well as with 10 and 100 mg/L of lead nitrate. A linear, dose dependent increase was obtained for both salts. Similar results were obtained on the basis of the mitotic index.

Cell Division↗
PubMed2002

[BSE--consequences for slaughtering, cutting and employer's protection].

The conventional slaughtering of cattle includes some critical process stages where a carry over of BSE-risk material (brain, spinal cord) on the meat can occur. These processes are captive bolt stunning, cut off the head and first of all sawing the spine lengthways. Alternative stunning methods like electrical stunning or concussion stunning are under investigation, nevertheless they are in the moment no useful alternatives for most of the slaughter houses. The most promising methods available at present for minimising the risk appear to be in manual cattle slaughtering boning the entire carcass, either still warm or refrigerated and in industrial beef cattle slaughtering extraction of the spinal cord by vacuum from the whole carcass followed by conventional sawing or completely sawing out the spine including spinal ganglia. Working processes, including the cutting or exposure of risk material, are a risk for the employer's too. Special protective measures must be taken.

Abattoirs↗
PubMed2004

Effect of a novel oil extraction method on avocado (Persea americana Mill) pulp microstructure.

Avocado (Persea americana Mill) is an oil-rich fruit, the pulp containing up to 33% of the oil. It is rich in monounsaturated fatty acids, and has nutritional properties similar to olive oil. However, there is no widespread commercial method for oil recovery from avocado pulp. The aim of this study is to contribute to the limited knowledge about the micro- and ultrastructure of avocado. It presents a micro- and ultrastructural study of avocado pulp before and after three different oil recovery methods, in order to relate the quality and yielding of the oil to the cellular changes in the pulp. This study was made using light, scanning electron, and electron transmission microscopy. The microwave-squeezing method yielded 67% of the oil, preserved the shape of the cell by causing only a slight modification, and gave the best quality oil. Hexane extraction yielded 59%, causing the idioblastic oil cells to become irregularly shaped and rough-surfaced. Acetone extraction yielded 12%, and deformed the cellular wall while the oil remained inside, giving a poor quality oil. On the basis of these results, the microwave-squeezing method is suggested as a new option for oil recovery from avocadopulp. This method could be adapted for industrial processing.

Chemical Phenomena↗
PubMed2006

The role of interparticle forces in colloidal aggregates: local investigations and modelling of restructuring during filtration.

Industrial solid-liquid separation processes, such as pressure filtration or membrane processes, involve the application of pressure to suspensions. In response, some water is extracted, the suspension volume is reduced, and the dispersed aggregates start to form a network. In recent works, we aimed to make a prediction for the response of aggregates to stress which occurs during a filtration. We chose model systems made of aggregated silica nanoparticles. Some of these systems offer a strong resistance to applied stresses, and retain their permeability; others yield and collapse. We used small angle neutron scattering by which we can locally quantify the particle distribution withi the network to determine the processes by which particles reorganise during collapse: we found that reordering processes at the scale of 1 to 10 particle diameters control the course of collapse and the loss of permeability. Finally we constructed a numerical model for describing the processes by which colloidal aggregates are compressed. This model predicts that the response of such networks to pressure follows some scaling laws, which depend only on the elastic vs. dissipative nature of interparticle bonds.

Aluminum↗
PubMed2005

Influence of origin and extraction method on argan oil physico-chemical characteristics and composition.

Twenty one samples of argan oil of different geographical origin (Tidzi, Tamanar, Benaiznassen, Ait mzal, Ait Baha, Ighrem, Aoulouz) and/or prepared following a different process (traditional, mechanical, or industrial) were collected and their physico-chemical properties analyzed. Sample acidity was found between 0.14 and 1.40%, unsaponifiable matter between 0.34 and 0.79%, saponification value between 180.0 and 199.6, highest peroxide index was 5.72 meq/kg, refractive index (20 degrees C) between 1.4644 and 1.4705, and UV absorption at 270 nm between 0.228 and 0.605. This study, carried out on randomly selected samples, clearly demonstrates that press extraction does not alter either the chemical composition of argan oil or its physico-chemical characteristics. It also demonstrates that press extraction respects the critical factors reported for traditionally prepared oils and necessary to obtain a beneficial effect on human health (a specific fatty acid balance and high tocopherol and sterol levels). In addition, this study should be useful for the establishment of a national quality standard.

Chemical Phenomena↗
PubMedDate not supplied

Feature extraction from light-scatter patterns of Listeria colonies for identification and classification.

Bacterial contamination by Listeria monocytogenes not only puts the public at risk, but also is costly for the food-processing industry. Traditional biochemical methods for pathogen identification require complicated sample preparation for reliable results. Optical scattering technology has been used for identification of bacterial cells in suspension, but with only limited success. Therefore, to improve the efficacy of the identification process using our novel imaging approach, we analyze bacterial colonies grown on solid surfaces. The work presented here demonstrates an application of computer-vision and pattern-recognition techniques to classify scatter patterns formed by Listeria colonies. Bacterial colonies are analyzed with a laser scatterometer. Features of circular scatter patterns formed by bacterial colonies illuminated by laser light are characterized using Zernike moment invariants. Principal component analysis and hierarchical clustering are performed on the results of feature extraction. Classification using linear discriminant analysis, partial least squares, and neural networks is capable of separating different strains of Listeria with a low error rate. The demonstrated system is also able to determine automatically the pathogenicity of bacteria on the basis of colony scatter patterns. We conclude that the obtained results are encouraging, and strongly suggest the feasibility of image-based biodetection systems.

Algorithms↗
PubMed1984

Aflatoxin distribution in edible oil-extracting plants and in poultry feedmills.

The occurrence and distribution of aflatoxins B1, B2, G1 and G2 in the raw materials and products of three plants for extracting edible oils and in two poultry feedmills in which by-products of the oil extraction were used for feed formulation were investigated. While levels of aflatoxins were high in the products and by-products from the three extraction plants, the levels in the poultry feeds produced in the feedmills were found to be relatively low. The latter finding may reflect the proportion of pellets included in the feedstock formulation, while the climatic differences in the areas in which the extraction plants were situated were a possible factor in the differing levels of aflatoxin found in the samples from the three extraction plants.

Aflatoxins↗
PubMed1995

Identification of important allergenic proteins in extracts of the granary weevil (Sitophilus granarius).

This paper describes the identification of important allergens from the granary weevil (Sitophilus granarius) (Sg). Sera from Danish bakers whose skin prick tests were positive to extracts of Sg were screened for IgE against Sg extracts. We found that 54% (n = 66) had elevated levels of IgE (RAST classes 1-3, by luminescent immunoassay) against whole-body extracts of Sg. The specificity of patient IgE was investigated in an inhibition-dot immunoblotting assay. IgE binding was inhibited in all sera but two, thus indicating that the patients' IgE was indeed specific for the Sg extract. In crossed immunoelectrophoresis, 23 different proteins were identified. All RAST-positive sera were investigated in crossed radioimmuno-electrophoresis. At least 11 proteins in the Sg extract were capable of binding IgE. All individual sera reacted with at least four different proteins. The two most prominent allergens bound IgE from 88% and 100%, respectively, of the patients. These two are considered to be the most important allergens from Sg, and will be useful as markers in environmental immunochemical assays to detect allergens in samples from bakeries, grain stores, etc.

Adolescent↗
PubMed2004

Quantification and Purification of Mulberry Anthocyanins with Macroporous Resins.

Total anthocyanins in different cultivars of mulberry were measured and a process for the industrial preparation of mulberry anthocyanins as a natural food colorant was studied. In 31 cultivars of mulberry, the total anthocyanins, calculated as cyanidin 3-glucoside, ranged from $147.68$ to $2725.46$ mg/L juice. Extracting and purifying with macroporous resins was found to be an efficient potential method for the industrial production of mulberry anthocyanins as a food colorant. Of six resins tested, X-5 demonstrated the best adsorbent capability for mulberry anthocyanins (91 mg/mL resin). The adsorption capacity of resins increased with the surface area and the pore radius. Residual mulberry fruit juice after extraction of pigment retained most of its nutrients, except for anthocyanins, and may provide a substrate for further processing.

Journal Article↗