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[Identification of genotoxic compounds used in leather processing industry].

The release of mutagens from 7 carbon black-based leather dyes and from leather samples at various stages of finishing was determined. After vigorous treatment with toluene, 4 commercial dyes yelded mutagenic extracts on Salmonella typhimurium in the presence of microsomal enzymes. Only in one case were the responsible chemicals identified as polycyclic aromatic hydrocarbons. The low bioavailability of mutagens contained in carbon black and their low mutagenic activity suggest that the risk associated with the use of these dyes is probably negligible. Soxhlet extracts with ethanol from finished leather were mutagenic on strain TA98 of Salmonella typhimurium in the absence of S9 mix. Analysis of extracts of leather samples at various intermediate stages of processing showed that mutagenic activity was detectable after the colouring process. The responsible compound was identified as a nitroazo dye (Colour Index: Acid Brown 83), with a mutagenic potential of about 4 revertant/micrograms. Eighteen commercial tannins containing mainly Cr(III) sulphates were assessed for genotoxicity. Most were contaminated with Cr(VI), a known mutagenic and carcinogenic agent, at levels sufficient to induce an increased frequency of SCE (sister chromatid exchanges) in mammalian cells (CHO, chinese hamster ovary) tested in vitro.

Animals↗
PubMed2005

Biocatalytic preparation of natural flavours and fragrances.

During the past years biocatalytic production of fine chemicals has been expanding rapidly. Flavours and fragrances belong to many different structural classes and therefore represent a challenging target for academic and industrial research. Here, we present a condensed overview of the potential offered by biocatalysis for the synthesis of natural and natural-identical odorants, highlighting relevant biotransformations using microorganisms and isolated enzymes. The industrial processes based on biocatalytic methods are discussed in terms of their advantages over classical chemical synthesis and extraction from natural sources. Recent applications of the biocatalytic approach to the preparation of the most important fine odorants are comprehensively covered.

Biotechnology↗
PubMed2004

[Study on optimizing the extraction process of total free organic acids in Pinellia ternate Breit].

OBJECTIVE: To optimize the extraction process of total free organic acids in Pinellia ternate Breit. METHOD: The optimum extraction was investigated by total free organic acids determined by direct potential titration. The concentration of ethanol, amount of ethanol, extraction time and extraction times were the four factors in the experiment. RESULTS: The optimum extraction process was adding 10 times amount of 75% ethanol, refluxing for 2 times, 1 h each time. CONCLUSION: This extraction process shows higher yield of total free organic acids in Pinellia ternate Breit and is available for industrial production.

Acids↗
PubMed2005

Greenhouse gas emissions from Canadian peat extraction, 1990-2000: a life-cycle analysis.

This study uses life-cycle analysis to examine the net greenhouse gas (GHG) emissions from the Canadian peat industry for the period 1990-2000. GHG exchange is estimated for land-use change, peat extraction and processing, transport to market, and the in situ decomposition of extracted peat. The estimates, based on an additive GHG accounting model, show that the peat extraction life cycle emitted 0.54 x 10(6) t of GHG in 1990, increasing to 0.89 x 10(6) t in 2000 (expressed as CO2 equivalents using a 100-y time horizon). Peat decomposition associated with end use was the largest source of GHGs, comprising 71% of total emissions during this 11-y period. Land use change resulted in a switch of the peatlands from a GHG sink to a source and contributed an additional 15%. Peat transportation was responsible for 10% of total GHG emissions, and extraction and processing contributed 4%. It would take approximately 2000 y to restore the carbon pool to its original size if peatland restoration is successful and the cutover peatland once again becomes a net carbon sink.

Air Pollutants↗
PubMed2004

Organic aerosols and the development of allergic disorders.

The aim of this study was to investigate skin reactivity to organic dust extracts and total serum IgE and their relation to the prevalence of respiratory symptoms and ventilatory capacity in workers occupationally exposed to organic aerosols. It included workers employed in processing coffee, tea, dried fruits, spices, animal food, soy, hemp, cotton, swine farmers, and control groups of workers non-exposed to organic dust. All underwent a skin prick test (SPT) with water extracts of organic dust 1:10 w/v, Dermatophagoides pteronyssinus, mixed moulds, bacteria, histamin solution (1 mg/ml) and buffer solution. SPT was considered positive if the diameter of the observed wheal was 3 mm greater than that of buffer solution. The total IgE was measured by the PRIST method (Pharmacia Diagnostics AB, Upsala) and the values > 125 kU/L were considered increased. Data on respiratory symptoms were collected by standardized questionnaire. Ventilatory capacity was measured by recording MEFV curve. Airborne industrial dust were measured as total and respirable fraction. The exposed workers had a greater prevalence of positive SPT to organic dust extracts, except in soy processing. Increased IgE was found in workers processing coffee, tea, hemp, cotton and animal food, compared to non-exposed workers (P<0.05). Workers with positive SPT had a significantly higher total IgE. As there was no correlation between acute and chronic changes in ventilatory function, positive SPT, and level of total IgE, our findings could not predict objective respiratory impairment.

Adult↗
PubMed2000

Simulated dynamics and control of an extractive alcoholic fermentation.

In this study, we investigated the dynamics of a computer simulation of a continuous alcoholic fermentation process combined with a flash column under vacuum. The alcohol was partially extracted in order to maintain its concentration at about 40 kg/m3 in the fermentor. The mathematical model of the fermentation was developed for industrial conditions and considers the effect of the temperature on the kinetic parameters. The performance of the dynamic matrix control algorithm, single input single output and multiple input multiple output, for the control of the extractive process was studied. The concepts of factorial design were used in a simulation study to determine the best control structures for the process.

Biomass↗
PubMed2003

Practical applications approach to design, development and implementation of an integrated management system.

The introduction of quality, risk, safety, health and environmental management philosophies has significantly changed industry's view of company organization and controlling processes. Quality, risk, safety, health and environmental programs and systems, such as ISO 9000, ISO 14000, process safety, and risk management are impacting the way industry will meet the challenges of safety and environmental risks and the needs of the customer in the future.A wealth of knowledge has been extracted from practical application case studies, which would otherwise be unobtainable without years of experience related to management systems design, development, implementation and control. This paper discusses a practical applications approach to design, develop and implement an integrated management system encompassing quality (ISO 9000), process safety management (CFR 29 1910.119), risk management programs (CFR 40 part 68), environmental management (ISO 14000), and safety and health. This paper includes a discussion of management systems integration and an overview of management systems standards that apply to the petrochemical and chemical manufacturers industries. The paper also provides an overview on integrating management systems, including issues related to the following topics: Establishing a management system team and objectives. Assessing and knowing your organization. Designing the management system to meet site objectives. Developing system documentation. Implementing effective management systems. Measuring program performance. Continuous improvement.

Carcinogens↗
PubMed2003

Effects of bacterial treatments on wood extractives.

Bacterial strains were isolated from spruce wood chips and their ability to reduce the content of wood extractives was studied. Strains were screened by cultivation on liquid media containing wood extractives as the major nutrient. Some bacterial species could decrease remarkably the amount of extractives in the liquid media and reduced the amount of triglycerides, steryl esters and total extractives by 100, 20 and 39%, respectively. Spruce wood chips were treated in controlled conditions with selected bacteria to test their effects on the chips. All the bacteria grew well on wood chips. The effect of bacterial metabolism on wood extractives was significant. Bacterial treatments reduced the amount of lipophilic extractives by 16-38% in 1 week of treatment and up to 67% in 2 weeks. The most efficient strain removed 90, 66 and 50% of triglycerides, steryl esters and resin acids, respectively, in 2 weeks. These results indicate that bacteria may be promising agents for the removal of extractives for improved pulping and papermaking processes.

Bacteria↗
PubMed2003

Separation and recovery of radioactive and non-radioactive toxic trace elements from aqueous industrial effluents.

An update is presented on liquid membrane-based processes as viable and relevant alternatives to conventional approaches such as precipitation, solvent extraction, ion exchange processes and electrochemical techniques for the removal and recovery of some toxic and/or valuable trace metal ions including some actinides and fission products e.g. U, Am, Y etc and As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Zn etc from radioactive as well as non-radioactive aqueous waste solutions respectively. In particular, results of experiments aimed at developing supported liquid membrane(SLM)-based process using commercially available porous membranes and indigenously prepared track--etch membranes (TEMs) have been critically examined in laboratory studies to generate basic data needed to evaluate their utility for continuous operation without regeneration. These include effect of pore size, porosity, optimum pore size and their reusability. It is clearly demonstrated that indigenously prepared 10 microm thick TEMs with a porosity in the range of 2-5% give comparable transport rates for metal ions-matching with that of commercial membranes of much higher thickness (160 microm) and higher porosity of 60-85%. The smaller thickness of TEMs more than compensates for their lower porosity. It is shown that because of their well defined pore characteristics TEMs could serve as model supports in SLM studies. By comparing the values of permeability coefficient (P) for TEM and polytetraflouroethylene (PTFE) supports for the transport of Pb2+ chosen as a typical divalent metal ion, and using di-2 ethyl hexyl phosphoric acid (D2EHPA) as the carrier, it is unambiguously proved that diffusion of the metal complex across the membrane is the rate controlling step in metal ion transport in SLM-based processes. An overview of the experimental findings along with future outlook and suggestions for further work are presented in this paper.

Actinoid Series Elements↗
PubMed2006

Dense gas processing of micron-sized drug formulations incorporating hydroxypropylated and methylated beta-cyclodextrin.

PURPOSE: Because of their importance in pharmaceutical applications, hydroxypropyl-beta-cyclodextrin and methyl-beta-cyclodextrin have been selected to study the formation of micronized complexes incorporating active pharmaceutical ingredients (APIs) and cyclodextrins (CDs) by dense gas (DG) processing. METHODS: A single-step DG technique was used as an alternative to conventional methods for the manufacturing of API/CD complexes. The DG technology is highly attractive in the pharmaceutical industry because of its potential to generate micronized particles with controlled particle size distributions at moderate operating conditions. The effect of the aerosol solvent extraction system (ASES) processing on the dissolution performance of naproxen (NPX) was examined. RESULTS: The CDs were produced as microspheres smaller than 3 microm. The coprecipitation of each CD with NPX resulted in the production of microparticles with enhanced dissolution rates. CONCLUSIONS: The ASES was operated under mild conditions and generated micron-sized spherical particles that could be of particular interest in formulations for pulmonary delivery. Particular advantages of the technique are that (1) nontoxic solvents are used, and (2) it is suitable for the processing of thermally labile compounds. The proposed process can create opportunities to improve current administration routes and exploit novel delivery systems for drug formulations incorporating CDs.

2-Hydroxypropyl-beta-cyclodextrin↗
PubMed1999

Recovery of hesperidin from orange peel by concentration of extracts on styrene-divinylbenzene resin.

This paper describes a new procedure for obtaining hesperidin from the waste orange peel of the citrus industry. It is based on the adsorption of dilute extracts of hesperidin on a styrene-divinylbenzene (SDVB) resin and the desorption in much more reduced volumes by means of alkaline eluents. Hesperidin immediately precipitates with good yield and high purity after acidification of the concentrated solutions, thus overcoming disadvantages due to the high dilution. Different experiments were carried out to examine operating conditions in each phase of the process. Hesperidin was extracted from peel with an aqueous saturated Ca(OH)(2) solution, allowing precipitation of calcium pectates from colloidal pectins that can interfere in the subsequent phases of adsorption and separation of hesperidin. The clear extracts were neutralized to optimize adsorption on resin. The most effective eluent was 0.5 N NaOH solution containing 10% ethanol. Recycling of the crystallization liquor improved the yield and purity of the product and reduced the acid amount required for neutralizing fresh alkaline extracts. Resin must be washed after each adsorption-desorption cycle and regenerated after five cycles. Results can constitute a useful starting point for an industrial application. A flow scheme of the process is also reported.

Adsorption↗
PubMed1996

Partitioning and purification of monoclonal antibodies in aqueous two-phase systems.

The partition behaviour of pure IgG in aqueous two-phase systems was examined in order to investigate the effects of changes in phase properties on the partition coefficient, K. Factors such as molecular weight (M.W.) of PEG, pH, and concentration of NaCl and other salts were all found to influence K. Due to the high level of interaction between the phase components, optimal conditions were found using a factorial design. Using this methodology it was possible to find conditions which gave extremely high values of K for the IgGs (> 100). Partition behaviour of some potential contaminants, BSA and transferrin, were also studied. All the components were characterized for hydrophobicity, pI and M.W. Conditions were chosen under which the partition coefficients of the contaminants was low (pH 6, 15% PEG 1450, 14% Phosphate and 12% NaCl). Precipitation of IgG was also minimized. These conditions were chosen for the extraction of IgG from the contaminants in a crude concentrated supernatant. The presence of culture media contaminants had a strong effect in the systems and hence on the partition of IgG which was lower than for pure IgG. The ratio of KIgG/Kcont was > 25. The conditions chosen for the first forward extraction into the PEG rich phase were 15% PEG 1450, 14% phosphate 12% NaCl and pH 5.5. Virtually all IgG partitioned to the top phase and the contaminants to the bottom phase. Optimal conditions for the back extraction of the IgGs into a bottom salt phase were also found (addition of 14% phosphate with no NaCl). An industrial serum free, crude, concentrated culture supernatant of hybridoma produced murine IgG, with a relatively low level of protein contaminants (14% IgG purity) was processed in this system. After the back extraction the contaminants were reduced 18 fold giving IgG with 80% purity. A 5.9 fold purification was obtained out of a 7.3 maximum possible (at 100% pure IgG). All of the IgG was recovered.

Antibodies, Monoclonal↗
PubMed2005

Environmental effects of interstate power trading on electricity consumption mixes.

Although many studies of electricity generation use national or state average generation mix assumptions, in reality a great deal of electricity is transferred between states with very different mixes of fossil and renewable fuels, and using the average numbers could result in incorrect conclusions in these studies. We create electricity consumption profiles for each state and for key industry sectors in the U.S. based on existing state generation profiles, net state power imports, industry presence by state, and an optimization model to estimate interstate electricity trading. Using these "consumption mixes" can provide a more accurate assessment of electricity use in life-cycle analyses. We conclude that the published generation mixes for states that import power are misleading, since the power consumed in-state has a different makeup than the power that was generated. And, while most industry sectors have consumption mixes similar to the U.S. average, some of the most critical sectors of the economy--such as resource extraction and material processing sectors--are very different. This result does validate the average mix assumption made in many environmental assessments, but it is important to accurately quantify the generation methods for electricity used when doing life-cycle analyses.

Electricity↗
PubMed2002

High-throughput method for the production and analysis of large natural product libraries for drug discovery.

High-throughput methods were applied to the production, analysis, and characterization of libraries of natural products in order to accelerate the drug discovery process for high-throughput screening in the pharmaceutical and biotechnology industries. Library production integrates automated flash chromatography, solid-phase extraction, filtration, and high-throughput parallel four-channel preparative high-performance liquid chromatography to obtain the libraries in 96- or 384-well plates. Libraries consist of purified fractions with approximately one to five compounds per well. Libraries are analyzed prior to biological screening by a high-throughput parallel eight-channel liquid chromatography-evaporative light scattering detection-mass spectrometry system to determine the molecular weight, number, and quantity of compounds in a fraction. After biological screening, active fractions are rapidly purified at the microgram level and individual compounds are rescreened for confirmation of activity. Structures of active compounds are elucidated by NMR spectroscopy and mass spectrometry. Utilization of a novel microcoil probe allows NMR data to be gathered on 50 microg. As a demonstration, a library was made from the stem bark of Taxus brevifolia. Biological screening in the National Cancer Institute's in vitro panel of three cancer cell lines demonstrates that the process enables the discovery of active anticancer compounds not detected in the flash fractions from which the library originates.

Biological Factors↗
PubMed2006

A direct electrochemical route from ilmenite to hydrogen-storage ferrotitanium alloys.

An unrecognised but predictable need for a hydrogen-supported society is tens or even hundreds of million tonnes of hydrogen-storage materials, and thus challenges existing technologies in terms of resource and economical realities. Ilmenite is an abundant mineral, and ferrotitanium alloys are among the earliest known hydrogen-storage materials. At present, industrial production of ferrotitanium alloys goes through separate extraction of individual metals, followed by a multistep arc-melting process. In particular, the extraction of titanium from ilmenite is highly energy intensive and tedious, accounting for titanium's high market price and restricted uses. This article reports the electrochemical synthesis of various ferrotitanium alloy powders directly from solid ilmenite in molten calcium chloride. More importantly, it demonstrates, for the first time, that such produced alloy powders can be used without further treatment for hydrogen storage and perform comparably with or better than similar products by means of other methods, but cost just a fraction.

Journal Article↗
PubMed2005

Quantification of the carbapenem antibiotic ertapenem in human plasma by a validated liquid chromatography-mass spectrometry method.

BACKGROUND: Ertapenem (Invanz) is a newly developed carbapenem beta-lactam antibiotic. LC-MS is the method of choice for therapeutic drug monitoring (TDM) of a variety of drugs including antibiotics. No validated LC-MS method for ertapenem quantification is described in the literature so far. METHODS: A rapid and robust LC-MS quantification method for ertapenem was developed and validated for clinical routine application in plasma samples. After immediate stabilisation with MES buffer (pH 6.5), samples were prepared for LC-MS analysis using simple protein precipitation. LC-MS coupling was realised by the use of a Phenomenex Synergi 4micro Polar-RP A80 Mercury LC column (10 x 2.0 mm) in combination with a Single-MS (Agilent 1100 LC-MSD SL) operating in negative selected ion monitoring (SIM) detection mode with ceftazidime as internal standard for adequate selective and sensitive analysis. RESULTS: LC-MS method validation by means of determination of limit of detection (LOD 0.1 microg mL-1), lower limit of quantification (LLOQ 1 microg mL-1), linearity (0.1-50 microg mL-1), recovery (> 90%), intra- and inter-day precision (RSD < 10%), accuracy (> 90%), inter-subject variability (< 10% at LLOQ), drug stability in plasma (> 3 months) and in post-extracted samples (> 99% for 24 h), and matrix effects (process efficiency > 90%) showed excellent performance parameters considering Guidance for Industry - Bioanalytical Method Validation. CONCLUSION: This method is perfectly appropriate for routine quantification of ertapenem and possibly other polar carbapenem beta-lactam antibiotics.

Calibration↗
PubMed1982

Ginger--chemistry, technology, and quality evaluation: part 1.

Ginger is used in more ways than any other spice. This monograph, published in two parts, comprehensively reviews production, trade, processing, chemistry, and evaluation of quality. Botany, world varieties, agronomy, crop improvement and potential are reviewed briefly with emphasis on the yield of functional components. Processing for the market, international trade patterns, and factors influencing them are discussed. Derived products such as ginger powder, syruped ginger, volatile oil, and oleoresin are discussed in greater detail. The increasing world demand for quality products of added value such as the oleoresin and volatile oil show prospects for their production in the growing countries. The chemistry of the components which contribute aroma and pungency that characterize ginger is critically reviewed. The second part deals with evaluation of quality. The physico-chemical parameters prescribed as a measure of quality for ginger and its products in the existing standards can assure only hygienic quality and purity, and possibly the source, when new parameters such as GC-fingerprints are included. The importance of sensorily evaluating flavor quality is emphasized to understand the variation in flavor quality required by the industrial and retail markets. Related areas, such as problems in sensory evaluation of intense flavored substances, objective flavor profile analysis, and correlation of instrumental and sensory data, are discussed and our recent work in this area is summarized. Areas where more research are needed are indicated. Other areas briefly discussed are functional, physiological, and toxicological properties in use of ginger; biosynthetic aspects of the components stimulating flavor; and structure and pungency and chemistry of spices from allied species and genera. A comprehensive bibliography is provided to aid in further study and research.

Chemical Phenomena↗