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PubMed2000

[Technology for the whole utilization of brewer's yeast in food industry].

A flexible scheme for the fractionation of brewer's yeast was developed. The procedure allows the production of different products such as: dry yeast flakes, dry yeast pills, yeast-extract based table sauce, yeast protein concentrates and soy-like sauce. The investment required for the processing of one ton per day is below 2 million dollars with an overall profitability higher than 53%. Investment is recovered in 0.75 years. The production of food ingredients from yeast upgrades its biomass about 25 fold. Present procedure is compared with other biomass fractionation processes taking into account the utilization of all technological streams where the process becomes environmentally friendly since effluent production significantly lower than similar technologies.

Analysis of Variance↗
PubMed2006

A functional-based segmentation of human body scans in arbitrary postures.

This paper presents a general framework that aims to address the task of segmenting three-dimensional (3-D) scan data representing the human form into subsets which correspond to functional human body parts. Such a task is challenging due to the articulated and deformable nature of the human body. A salient feature of this framework is that it is able to cope with various body postures and is in addition robust to noise, holes, irregular sampling and rigid transformations. Although whole human body scanners are now capable of routinely capturing the shape of the whole body in machine readable format, they have not yet realized their potential to provide automatic extraction of key body measurements. Automated production of anthropometric databases is a prerequisite to satisfying the needs of certain industrial sectors (e.g., the clothing industry). This implies that in order to extract specific measurements of interest, whole body 3-D scan data must be segmented by machine into subsets corresponding to functional human body parts. However, previously reported attempts at automating the segmentation process suffer from various limitations, such as being restricted to a standard specific posture and being vulnerable to scan data artifacts. Our human body segmentation algorithm advances the state of the art to overcome the above limitations and we present experimental results obtained using both real and synthetic data that confirm the validity, effectiveness, and robustness of our approach.

Algorithms↗
PubMed1999

Selective cloning of peanut allergens, including profilin and 2S albumins, by phage display technology.

BACKGROUND: Peanut kernels contain many allergens able to elicit IgE-mediated type 1 allergic reactions in sensitized individuals. Sera from sensitized patients recognize variable patterns of IgE-binding proteins. The identification of the IgE-binding proteins of peanut extract would faciliate improvement of diagnostic and immunotherapeutic approaches as well as development of sensitive test systems for the detection of hidden peanut allergens present as additives in various industrial food products and the investigation of their stability during processing of food products. METHODS: We applied the pJuFo cloning system based on the phage surface display of functional cDNA expression products to clone cDNAs encoding peanut allergens. Sera (n = 40) of peanut-allergic individuals were selected according to case history, radioallergosorbent test and immunoblot analysis to demonstrate IgE binding towards the newly identified recombinant allergens. RESULTS: In addition to the known allergens Ara h 1 and Ara h 2 we were able to identify four allergens with estimated molecular weights of 36, 16, 14.5 and 14 kDa. Three of them formally termed Ara h 4, Ara h6 and Ara h 7 show significant sequence similarities to the family of seed storage proteins and the fourth (Ara h 5) corresponds to the well-known plant allergen profilin. Immunoblotting of the six expressed recombinant allergens with 40 patients sera shows 14 individual recognition patterns and the following frequency of specific IgE binding: Ara h 1 was recognized by 65%, Ara h 2 by 85%, Ara h 4 by 53%, Ara h 5 by 13%, Ara h 6 by 38% and Ara h 7 by 43% of the selected sera. CONCLUSIONS: All of the selected peanut-positive sera can detect at least one of the six identified recombinant allergens which can be used to establish individual patients' reactivity profiles. A comparison of these profiles with the clinical data will possibly allow a further insight into the relationship between clinical severity of the symptoms and specific IgE levels towards the six peanut allergens.

2S Albumins, Plant↗
PubMed1983

Carcinogenicity of airborne combustion products observed in subcutaneous tissue and lungs of laboratory rodents.

Most air pollution in West Germany is caused by combustion products. Particulate organic matter released by incomplete combustion is suspected to contribute to the "urban factor" of lung cancer frequency in urban-industrial centers. The carcinogenic potential of single components, groups of compounds and total source emissions of combustion processes was investigated in laboratory animals by subcutaneous injection, intratracheal instillation or inhalation. Tests by subcutaneous injection of condensates of automobile exhaust, extracts of coal furnace emissions and of airborne particles and different fractions of these extracts showed that the polycyclic aromatic hydrocarbons (PAH) with four to six benzene rings have the strongest experimental carcinogenicity. However, polar compounds (heterocyclic nitrogen-containing PAH, phenols, and others) also show remarkable carcinogenic potency. There were large differences between the dose-response relationships of several PAHs. In the subcutaneous tissue, benzo(a)pyrene and dibenz(a,h)anthracene are the most carcinogenic of the tested airborne PAHs. Furthermore, they can induce high tumor rates in the lung after subcutaneous injection in newborn mice and after intratracheal instillation of mice or hamsters. The tumor rate of benzo(a)pyrene did not further increase after simultaneous instillation of carbon black, but lead chloride may have a promoting effect. Far more than 100 PAHs are found in the urban atmosphere. However, because of the remarkable similarity of the PAH profiles in the examined samples, it may be sufficient to measure just a few stable PAHs in the urban air in order to facilitate an assessment of the carcinogenic potency of the PAH content in the atmosphere. To examine the carcinogenic or cocarcinogenic effects of gas and vapor emissions, studies with a two-phase model were carried out: phase 1 relates to the induction of a basic tumor rate in the lung by a well known carcinogen, while phase 2 is characterized by an inhalation of the substance under investigation. In an experiment with mice, the inhalation of a mixture of SO2 and NO2 seemed to increase the basic tumor rate induced by dibenz(a,h)anthracene. In a similar two-phase experiment conducted with hamsters, the inhalation of diesel exhaust (total exhaust as well as exhaust without particles) increased a basic tumor rate induced by diethyl nitrosamine. These experiments deserve confirmation before a detailed interpretation is attempted.

Air Pollutants↗
PubMedDate not supplied

[Accumulation of uranium, plutonium and americium by granulated microbial biosorbent].

A possibility of efficient extraction of 238U, 239Pu and 241Am by microorganisms from solutions with activity 520-3200 Bq/l has been shown on the example of microbial biosorbent (MBS). MBS presents water-resistant granules consisting of living microorganisms and nutrient substances. The ratio MBS:solution being equal to 1:100 and 1:20, microorganisms extracts 98.9 and 99.8% of 238U; 99.1 and 99.8% of 239Pu, 241Am, respectively. The worked out MBC granules may be utilized by burning with the 4-8 decrease of the volume. It is foreseen to use MBS in industrial processes of treatment of liquid radioactive waste (LRW) for uranium and transuranium elements.

Absorption↗
PubMed2001

Removal and recovery of heavy metals from wastewaters by supported liquid membranes.

The removal and recovery of Cu, Cr and Zn from plating rinse wastewater using supported liquid membranes (SLM) are investigated. SLMs with specific organic extractants as the liquid membrane carriers in series are able to remove and concentrate heavy metals with very high purity, which is very promising for recycling of heavy metals in the electroplating industry. A technical comparison between the membrane process and the conventional chemical precipitation process was made.

Conservation of Natural Resources↗
PubMed1999

Quantification of re-evaporated mass from loaded fibre-mist eliminators.

Airborne lubricant emissions are a serious health hazard for employees in the metal working industry. The basic components of lubricants are oils and additives for adapting the properties to achieve the process demands. The oils used in lubricants are either mineral, synthetic or of biological origin. The lubricants are used as water-emulsions and also as straight oils. Extreme process conditions cause considerable amounts of aerosol and vapour emissions of lubricants into the working environment. Fibre filters are used in industrial demisters for pollution control and also for sampling purposes. Re-evaporation of separated lubricants from loaded fibre filters causes increased vapour emissions. Quantification of lubricant vapour emission was the subject of this research. An apparatus and an appropriate procedure for measuring the dynamic behaviour of evaporative losses from fibre filters were developed. The test piece of a loaded fibre filter was fixed in a sampling probe according to VDI 2066. The vapour concentration of organic compounds in downstream air was measured in real-time by using a photo-ionisation detector (PID). The PID was checked by sampling the vapour on an oleophilic adsorbent resin, solvent extraction and quantitative IR analysis and also gravimetrically. The two basic processes of filtering volatile aerosols are, on the one hand, collecting droplets on the fibres and, on the other hand, the evaporation of collected liquid. These two processes had to be separated in order to measure the increase of the vapour concentration caused by the tested fibre filter. The experiments were carried out using pure dodecane and hexadecane in order to avoid difficulties due to the unknown chemical composition of lubricant vapour. The variation of the air flow and the initial liquid mass on the filter covered the relevant range for industrial fibre demisters and for sampling methods based on collecting aerosols on fibre filters. It was found that the downstream air was saturated with lubricant vapour for a wide range of filter loads and filtration velocities. From the results obtained it can be concluded that loaded industrial filter systems emit air with saturation vapour concentration throughout their operation. Hence, vapour emissions can be estimated easily if the saturation vapour pressure and the mean relative molecular mass are known. Moreover, results obtained from measurements of filters with low loads confirm that the phase transition from liquid to vapour is influenced by the identified process parameters. This is relevant for measurement methods using fibre filters for sampling volatile aerosols. A semi-empirical model to estimate the evaporative losses for low loadings is proposed. However, further research is necessary to determine the full range of parameters that are relevant for evaporative losses from filters loaded with low masses of aerosols.

Air Pollution, Indoor↗
PubMed1976

Cottonseed colour fixed pigments. Part II. Role of hexane isomers on oil quality.

Colour fixed pigments can be detected in refined and bleached oils rather than in crude oils, since in the latter their absorption is masked up by the gossypol pigments. Isohexane is the most desirable hexane isomer. Though it produces darker crude oils, yet refinability and bleachability increases as the percentage of isohexane in normal hexan increases. It has also the advantage of extracting oils with lowest refining loss and with the highest gossypol content. Recovery of gossypol, which is alkali refinable, with the oil results in a superior quality of meal. Benzene, on the other hand, is the least desirable constituent in commercial hexane. Its presence with n-hexane results in darker coloured crude, refined and bleached oil colours, indicating the selectivity of benzene to colour fixed pigments. Highest refining loss were found in oils extracted with benzene or benzene-hexane solvent mixtures. Cyclohexane presence with n-hexane (35% to 60%) and methycyclopentane (6.0% to 12.0%) do not increase the degree of extraction of colour fixed pigments, however increase the refining loss of the extracted oils.

Alkanes↗
PubMed2006

A hydrogen peroxide/ microwave advanced oxidation process for sewage sludge treatment.

This study focused on the efficacy of the microwave/hydrogen peroxide advanced oxidation process (MW/H2O2-AOP) on the secondary sludge treatment. The results indicated that at temperatures of 80 degrees C and above, essentially all of the chemical oxygen demand (COD) was solubilized by the combined MW/H2O2-AOP. This process also solubilized nutrients (nitrogen, phosphorus and metals) from sludge which can be extracted for other purposes, such as struvite crystallization. Based on a stoichiometric molar ratio of 1:1:1 for Mg:NH3:PO4, ammonia was found to be the limiting nutrient without any H2O2 addition in the process at all temperatures. With the addition of H2O2, ortho-phosphate became the limiting nutrient. In all treatments, magnesium was non-limiting, thus magnesium addition is not required for subsequent struvite crystallization. The MW/H2O2-AOP also enhanced the pasteurization or sterilization of sludge. The MW/H2O2-AOP provides novel sludge management options for the wastewater industry, not only in solubilization of carbon for further methane production, but also in nutrients extraction for crystallization for use as fertilizer.

Aerobiosis↗
PubMed2006

Hydrogen peroxide synthesis: an outlook beyond the anthraquinone process.

Hydrogen peroxide (H2O2) is widely used in almost all industrial areas, particularly in the chemical industry and environmental protection. The only degradation product of its use is water, and thus it has played a large role in environmentally friendly methods in the chemical industry. Hydrogen peroxide is produced on an industrial scale by the anthraquinone oxidation (AO) process. However, this process can hardly be considered a green method. It involves the sequential hydrogenation and oxidation of an alkylanthraquinone precursor dissolved in a mixture of organic solvents followed by liquid-liquid extraction to recover H2O2. The AO process is a multistep method that requires significant energy input and generates waste, which has a negative effect on its sustainability and production costs. The transport, storage, and handling of bulk H2O2 involve hazards and escalating expenses. Thus, novel, cleaner methods for the production of H2O2 are being explored. The direct synthesis of H2O2 from O2 and H2 using a variety of catalysts, and the factors influencing the formation and decomposition of H2O2 are examined in detail in this Review.

Journal Article↗
PubMed1990

Fibroblast behavior on gels of type I, III, and IV human placental collagens.

Various collagens were extracted and purified from human placenta after partial pepsin digestion. We prepared type III + I (57:43), enriched type I, type III, and type IV collagens on an industrial level, and studied their biological properties with MRC5 fibroblast cells. Using the process of contraction of a hydrated collagen lattice described by Bell, we found tha the contraction rate was dependent on collagen type composition. The contraction was faster and more pronounced with pepsinized type I collagen than with pepsinized type III + I (57:43) collagen; the lowest rate was obtained with the pepsinized type III collagen. Using a new technique of collagen cross-linking, a gel was made with type IV collagen. This cross-linking procedure, based on partial oxidation of sugar residues and hydroxylysine by periodic acid, followed by neutralization, resulted in an increased number of natural cross-link bridges between oxidized and nonoxidized collagen molecules, without internal toxic residues. The fibroblasts were unable to contract type IV/IVox collagen gels. The type IV/IVox collagen gel was transparent and its amorphous ultrastructure lacked any visible striated fibrils. Fibroblast cells exhibited atypical behavior in these type IV/IVox collagen gels as evidenced by optical and electron microscopy. The penetration of fibroblasts could be measured. Fibroblasts penetrated faster in type IV/IVox collagen gels than in untreated type III + I collagen gels. The lowest rate of penetration was obtained with cross-linked type III + I gels. Fibroblast proliferation was similar on untreated or cross-linked type III + I collagen gels and slightly increased on type IV/IVox collagen gels, suggesting that this cross-linking procedure was not toxic.

Cell Division↗
PubMed2002

Partitioning of olive oil antioxidants between oil and water phases.

The partition coefficient (K(p)) of the natural phenolic antioxidant compounds in the olive fruit between aqueous and olive oil phases was determined. The antioxidants of olive oil are either present in the olive fruit or formed during the olive oil extraction process. The antioxidants impart stability to and determine properties of the oil and are valuable from the nutritional point of view. The olive oil antioxidants are amphiphilic in nature and are more soluble in the water than in the oil phase. Consequently, a large amount of the antioxidants is lost with the wastewater during processing. The determination of antioxidants was performed using HPLC, and the K(p) was estimated to be from as low as 0.0006 for oleuropein to a maximum of 1.5 for 3,4-DHPEA-EA (di-hydroxy-phenyl-ethanol-elenolic acid, oleuropein aglycon). Henry's law fitted very well to the experimental data. The partition coefficients were also estimated by applying the activity coefficients of the antioxidants in the two phases using a predictive group contribution method, the UNIFAC equation. The K(p) values estimated with UNIFAC method were of the same order of magnitude but varied from the experimental values. Nevertheless, this method may be a rough predictive tool for process optimization or design. Because the K(p) values were very low, some changes in the process are recommended in order to achieve a higher concentration of antioxidants in the oil. A temperature increase may lead to increasing the partition coefficient. Also, limiting the quantity of water during oil extraction could be a basis for designing alternative processes for increasing the antioxidant concentration in the olive oil.

Antioxidants↗
PubMed2001

[The fate of dioxins during green tea manufacture].

Dioxin concentrations and homologue profiles were examined in plucked new shoots, crude tea and its hot water extracts, soils and atmosphere in tea orchards. The rate of dry provisions in crude tea has increased 4 times as that of the plucked new shoots. However, dioxin concentrations except O8CDD in crude tea have increased only 2 to 3 times as those of the plucked new shoots. O8CDD concentration increased remarkably during processing. Little dioxins were detected in hot water extracts of crude tea leaves.

Dioxins↗
PubMedDate not supplied

Barley, a potential species for initial reclamation of saline composite tailings of oil sands.

The oil sands industry in Alberta (Canada) has developed the composite tailings (CT) process to reduce the fluid fine tails resulting from the processing of oil sands. This process uses a chemical coagulant (gypsum or alum) to produce aggregated fines (clay), so they are retained with the coarse sand fraction of the extraction tailings to form CT, from which fines-free water is released relatively quickly compared with untreated tailings. The resulting CT and CT waters are saline-sodic, with Na+, SO4(2-), and Cl- being the dominant ions. When freshly deposited, the CT deposits are too soft for access by reclamation equipment, and the time required for these deposits to remove the water sufficiently to support traffic is uncertain. A greenhouse study was designed to determine the suitability of barley (Hordeum vulgare L.) for reclamation of fresh CT deposits and to evaluate benefits of peat amendments. This study assessed germination, early plant growth, chlorophyll content, and survival of barley growing in alum- and gypsum-treated CT, with and without peat amendment. Ion and trace metal accumulation in the root and shoot tissues of barley was determined. Amendment of CT with peat improved germination, survival, and growth of barley, but did not prevent leaf injury (probably due to Na and Cl- and possibly multiple nutrient deficiency). Field studies will be undertaken to validate our greenhouse results suggesting that barley could be used to improve dewatering of the freshly deposited substrates, reduce soil erosion, and facilitate leaching of ions by root penetration into the substrate.

Biodegradation, Environmental↗
PubMed2005

Metabolic engineering of Escherichia coli for industrial production of glucosamine and N-acetylglucosamine.

Glucosamine and N-acetylglucosamine are currently produced by extraction and acid hydrolysis of chitin from shellfish waste. Production could be limited by the amount of raw material available and the product potentially carries the risk of shellfish protein contamination. Escherichia coli was modified by metabolic engineering to develop a fermentation process. Over-expression of glucosamine synthase (GlmS) and inactivation of catabolic genes increased glucosamine production by 15 fold, reaching 60 mg l(-1). Since GlmS is strongly inhibited by glucosamine-6-P, GlmS variants were generated via error-prone PCR and screened. Over-expression of an improved enzyme led to a glucosamine titer of 17 g l(-1). Rapid degradation of glucosamine and inhibitory effects of glucosamine and its degradation products on host cells limited further improvement. An alternative fermentation product, N-acetylglucosamine, is stable, non-inhibitory to the host and readily hydrolyzed to glucosamine under acidic conditions. Therefore, the glucosamine pathway was extended to N-acetylglucosamine by over-expressing a heterologous glucosamine-6-P N-acetyltransferase. Using a simple and low-cost fermentation process developed for this strain, over 110 g l(-1) of N-acetylglucosamine was produced.

Acetylglucosamine↗
PubMed2000

Anaerobic-aerobic process for microbial degradation of tetrabromobisphenol A.

Tetrabromobisphenol A (TBBPA) is a flame retardant that is used as an additive during manufacturing of plastic polymers and electronic circuit boards. Little is known about the fate of this compound in the environment. In the current study we investigated biodegradation of TBBPA, as well as 2,4,6-tribromophenol (TBP), in slurry of anaerobic sediment from a wet ephemeral desert stream bed contaminated with chemical industry waste. Anaerobic incubation of the sediment with TBBPA and peptone-tryptone-glucose-yeast extract medium resulted in a 80% decrease in the TBBPA concentration and accumulation of a single metabolite. This metabolite was identified by gas chromatography-mass spectrometry (GC-MS) as nonbrominated bisphenol A (BPA). On the other hand, TBP was reductively dehalogenated to phenol, which was further metabolized under anaerobic conditions. BPA persisted in the anaerobic slurry but was degraded aerobically. A gram-negative bacterium (strain WH1) was isolated from the contaminated soil, and under aerobic conditions this organism could use BPA as a sole carbon and energy source. During degradation of BPA two metabolites were detected in the culture medium, and these metabolites were identified by GC-MS and high-performance liquid chromatography as 4-hydroxybenzoic acid and 4-hydroxyacetophenone. Both of those compounds were utilized by WH1 as carbon and energy sources. Our findings demonstrate that it may be possible to use a sequential anaerobic-aerobic process to completely degrade TBBPA in contaminated soils.

Aerobiosis↗
PubMed2000

Biosilicification: the role of the organic matrix in structure control.

Silicon (although never in the elemental form) is present in all living organisms and is required for the production of structural materials in single-celled organisms through to higher plants and animals. Hydrated amorphous silica is a mineral of infinite functionality and yet it is formed into structures with microscopic and macroscopic form. Research into the mechanisms controlling the process have highlighted proteins and proteoglycans as possible control molecules. Such molecules are suggested to play a critical role in the catalysis of silica polycondensation reactions and in structure direction. This article reviews information on silica form and function, silica condensation chemistry, the role of macromolecules in structure control and in vitro studies of silica formation using biomolecules extracted from biological silicas. An understanding of the mechanisms by which biological organisms regulate mineral formation will assist in our understanding of the essentiality of silicon to life processes and in the generation of new materials with specific form and function for industrial application in the 21st century.

Animals↗