Main Organic Components Research Articles

Characterization and sources assignation of PM2.5 organic aerosol in a rural area of Spain

The results from a year-long study of the organic composition of PM2.5 aerosol collected in a rural area influenced by a highway of Spain are reported. The lack of prior information related to the organic composition of PM2.5 aerosol in Spain, concretely in rural areas, led definition of the goals of this study. As a result, this work has been able to characterize the main organic components of atmospheric aerosols, including several compounds of SOA, and has conducted a multivariate analysis in order to assign sources of particulate matter. A total of 89 samples were taken between April 2004 and April 2005 using a high-volume sampler. Features and abundance of n-alkanes, polycyclic aromatic hydrocarbons (PAHs), alcohols and acids were separately determined using gas chromatography/mass spectrometry and high performance liquid chromatography analysis. The Σ n-alkane and ΣPAHs ranged from 3 to 81 ng m −3 and 0.1 to 6 ng m −3 respectively, with higher concentrations during colder months. Ambient concentrations of Σalcohols and Σacids ranged from 21 to 184 ng m −3 and 39 to 733 ng m −3, respectively. Also, several components of secondary organic aerosol have been quantified, confirming the biogenic contribution to ambient aerosol. In addition, factor analysis was used to reveal origin of organic compounds associated to particulate matter. Eight factors were extracted accounting more than 83% of the variability in the original data. These factors were assigned to a typical high pollution episode by anthropogenic particles, crustal material, plant waxes, fossil fuel combustion, temperature, microbiological emissions, SOA and dispersion of pollutants by wind action. Finally, a cluster analysis was used to compare the organic composition between the four seasons.

CEC for Studying the Retention and Separation of Pesticides on a Humic Acid Stationary Phase

A humic acid stationary phase is evaluated for studying by capillary electrochromatography (CEC) the binding of four pesticides with humic acid (HA), the main organic component in soil. It was demonstrated that the humic acid capillary was stable in terms of efficiency and retention during a long period of time. It appeared that HA has a lower affinity for neutral than for charged pesticides. The influence of the mobile phase constitution on the pesticide retention was also investigated in order to provide valuable information about the binding mechanism. The results suggest that the interactions of the pesticides during CEC are solely based on chromatographic mechanisms and that electrophoresis only plays a minor role. As well, it was shown that the HA stationary phase was able to separate these pesticides by CEC with a low analysis time. This HA capillary column could soon become attractive to determining the risk assessment of pesticides.

Assessing the efficiency of urban waste biocomposting by analytical pyrolysis (Py–GC/MS)

Analytical pyrolysis (Py–GC/MS) was used to study complex composting processes. The technique was first validated for reproducibility and finally applied to assess the efficiency of a microbial bio-accelerator product (CBB) in composting organic residues with different composition. Fresh lignocellulosic and urban wastes were treated with CBB and the composting kinetics studied to investigate the transformations undergone in the course of biocomposting. Our findings demonstrate that these changes, as well as the efficiency of CBB, can be monitored through the molecular characterization of the released pyrolysis products. The CBB bacterial product effectively seems to favour composting accelerating the process and shorten composting time. Analytical pyrolysis was informative in assessing to which extent compost transformation reached an acceptable stabilization point. The technique could be also developed into a semi-quantitative tool to monitor changes of main organic matter components (polysaccharides, proteins, lignin, lipids, etc.) as composting proceeds.

Biochemical composition and condition in anchovy larvae Engraulis encrasicolus during growth

Growth and condition of larval Engraulis encrasicolus larvae in the Bay of Biscay were analysed relative to their biochemical composition. Protein, carbohydrate, lipid, DNA and RNA contents of larvae were quantified during larval ontogeny to analyse changes associated with growth. Proteins were the main organic component of E. encrasicolus at every larval stage, followed by lipids and carbohydrates. The increase in relative protein content in terms of protein percentage (P%) and the decrease in lipid relative content (L%) of the total organic matter (OM) with size observed are consistent with the definition of Type 1 larvae. Protein relative content increased until the P% in larvae reached ~71%, whereas L% and carbohydrate relative content (CH%) declined, exhibiting minimum values of ~20, and ~6%, respectively. In general terms, the feeding condition of larvae, as defined by their RNA/DNA ratio, was good. Food did not seem to be a major factor limiting larval growth in the study area throughout late spring and early summer. The RNA/DNA ratio was size-related and increased during larval growth up to an asymptotic optimal value of ~3.6 in postflex- ion larvae in relative protein content, in terms of protein percentage (P%). The 'actual' RNA/DNA ratios found in a given larval population when compared with the 'starving' RNA/DNA ratio, and using an 'absolutely optimal' value as complementary information, could be used to determine the overall status of the population. Parental effect of low egg quality is a possible explanation of delayed ontogenetical development of larvae from July 2000.

Treatment of bromoamine acid wastewater using combined process of micro-electrolysis and biological aerobic filter

The wastewater originated from the production of bromoamine acid was treated in a sequential system of micro-electrolysis (ME) and biological aerobic filter (BAF). Decolorization and COD Cr removal rate of the proposed system was investigated with full consideration of the influence of two major controlling factors such as organic loading rate (OLR) and hydraulic retention time (HRT). The removal rate of COD Cr was 81.2% and that of chrominance could be up to 96.6% at an OLR of 0.56 kg m −3 d −1 when the total HRT was 43.4 h. Most of the chrominance was removed by the ME treatment, however, the BAF process was more effective for COD Cr removal. The GC–MS and HPLC–MS analysis of the contaminants revealed that 1-aminoanthraquinone, bromoamine acid and mono-sulfonated 1,2-dichlorobenzene were the main organic components in the wastewater. The reductive transformation of the anthraquinone derivatives in the ME reactor improved the biodegradability of the wastewater, and rendered the decolorization. After long-term of operation, it was observed that the predominant microorganisms immobilized on the BAF carriers were rod-shaped and globular. Four bacterial strains with apparent 16S rDNA fragments in the Denaturing Gradient Gel Electrophoresis (DGGE) profiles of BAF samples were identified as Variovorax sp., Sphingomonas sp., Mycobacterium sp., and Microbacterium sp.

Induction of (Z)-8-heptadecene in marine green alga Bryopsis maxima by mechanical wounding

After mechanical wounding of the marine green alga Bryopsis maxima in a phosphate buffer, one main organic component was released to the solution. The organic compound was characterized by a molecular ion at 238 m/z by gas chromatography-mass spectrometry (GC-MS) and was deduced as 8-heptadecene by the fragment pattern. To identify the stereochemistry of 8-heptadecene, synthetic (Z/E)-8-heptadecene was coinjected to the solution of wounded B. maxima. Comparing retention times and mass spectra with the synthetic sample, the target hydrocarbon obtained from wounded B. maxima was coincident with (Z)-8-heptadecene.

Development of Bone-Like Composite Material and its Properties

Many kinds of materials are currently used as artificial bone substitutes. Hydroxyapatite (HA), the same as the main inorganic component of bone, is one of commonly used bio-ceramics and has excellent bioactivity and biocompatibility with hard tissues. However, it has problems as the bone filler or bone tissue-engineering scaffold due to low fracture toughness and low degradation rate. Recently, biodegradable materials for bone tissue have been developed to respond the requirement. Collagen, the same as the main organic component of bone, is biocompatible, biodegradable and promotes cell adhesion. A composites associated with HA is expected to have early osteoconduction and bone replacement ability. The present study was to fabricate bone-like composites consist of HA and collagen. Besides the ossiferous ability of the material in vivo is evaluated by using rabbits. Bone-like composites were successfully fabricated in this study, associating the collagen with HA. And the composites presented good osteoconductive and bone replacement potential.

Fibrils of different collagen types containing immobilised proteoglycans (PGs) as coatings: Characterisation and influence on osteoblast behaviour

Collagen, the main organic component of bone, is used as a coating on titanium implants and as a scaffold material in bone tissue engineering. Surface modifications of titanium which promote osteoblast adhesion, proliferation and synthesis of collagen by osteoblasts are desirable. One biomimetic approach is the coating of titanium with collagen in fibrillar form. Other organic components of bone may be bound to fibrils and exert additional effects. In this study, the collagen types I–III were compared regarding their ability to bind the proteoglycans decorin and biglycan, which are found in bone. More collagen was bound to collagen II fibrils than to those of types I and III. Therefore, titanium surfaces were coated with fibrils of collagen type II containing biglycan or decorin or neither to investigate the effect of the proteoglycans on human primary osteoblast behaviour. In addition, the growth factor TGF-β1 was adsorbed onto surfaces coated with fibrils of collagen type II containing biglycan or decorin or neither to investigate the influence of decorin and biglycan on the effect of TGF-β1 on osteoblasts. Fibril-bound biglycan and decorin influence primary osteoblast behaviour by themselves. The presence of substrate-bound biglycan or decorin influences the effect of TGF-β1. These results may be important when designing collagen-based coatings or scaffolds for tissue engineering, including those loaded with growth factors.

Analyses of Soft Tissue from Tyrannosaurus rex Suggest the Presence of Protein

We performed multiple analyses of Tyrannosaurus rex (specimen MOR 1125) fibrous cortical and medullary tissues remaining after demineralization. The results indicate that collagen I, the main organic component of bone, has been preserved in low concentrations in these tissues. The findings were independently confirmed by mass spectrometry. We propose a possible chemical pathway that may contribute to this preservation. The presence of endogenous protein in dinosaur bone may validate hypotheses about evolutionary relationships, rates, and patterns of molecular change and degradation, as well as the chemical stability of molecules over time.

Cosima – High Resolution Time-of-Flight Secondary Ion Mass Spectrometer for the Analysis of Cometary Dust Particles onboard Rosetta

The ESA mission Rosetta, launched on March 2nd, 2004, carries an instrument suite to the comet 67P/Churyumov-Gerasimenko. The COmetary Secondary Ion Mass Anaylzer – COSIMA – is one of three cometary dust analyzing instruments onboard Rosetta. COSIMA is based on the analytic measurement method of secondary ion mass spectrometry (SIMS). The experiment’s goal is in-situ analysis of the elemental composition (and isotopic composition of key elements) of cometary grains. The chemical characterization will include the main organic components, present homologous and functional groups, as well as the mineralogical and petrographical classification of the inorganic phases. All this analysis is closely related to the chemistry and history of the early solar system. COSIMA covers a mass range from 1 to 3500 amu with a mass resolution m/Δm @ 50% of 2000 at mass 100 amu. Cometary dust is collected on special, metal covered, targets, which are handled by a target manipulation unit. Once exposed to the cometary dust environment, the collected dust grains are located on the target by a microscopic camera. A pulsed primary indium ion beam (among other entities) releases secondary ions from the dust grains. These ions, either positive or negative, are selected and accelerated by electrical fields and travel a well-defined distance through a drift tube and an ion reflector. A microsphere plate with dedicated amplifier is used to detect the ions. The arrival times of the ions are digitized, and the mass spectra of the secondary ions are calculated from these time-of-flight spectra. Through the instrument commissioning, COSIMA took the very first SIMS spectra of the targets in space. COSIMA will be the first instrument applying the SIMS technique in-situ to cometary grain analysis as Rosetta approaches the comet 67P/Churyumov-Gerasimenko, after a long journey of 10 years, in 2014.

Identification and quantification of the main organic components of vinegars by high resolution 1H NMR spectroscopy

A detailed analysis of the proton high-field NMR spectra of vinegars (in particular of Italian balsamic vinegars) is reported. A large number of organic substances belonging to different classes, such as carbohydrates, alcohols, organic acids, volatile compounds and amino acids, were assigned. The possibility of quantification of the substances identified in the whole vinegar sample, without extraction or pre-concentration steps, was also tested. The data validity was demonstrated in terms of precision, accuracy, repeatability and inter-day reproducibility. The effects of the most critical experimental parameters (sample concentration, water suppression and relaxation time) on the analysis response were also discussed. 1H NMR results were compared with those obtained by traditional techniques (GC–MS, titrations), and good correlations were obtained. The results showed that 1H NMR with water suppression allows a rapid, simultaneous determination of carbohydrates (glucose and fructose), organic acids (acetic, formic, lactic, malic, citric, succinic and tartaric acids), alcohols and polyols (ethanol, acetoin, 2,3-butanediol, hydroxymethylfurfural), and volatile substances (ethyl acetate) in vinegar samples. On the contrary, the amino acid determination without sample pre-concentration was critical. The 1H NMR method proposed was applied to different samples of vinegars, allowing, in particular, the discrimination of vinegars and balsamic vinegars.

FABRICATION OF BONE LIKE COMPOSITES MATERIAL AND EVALUATION OF ITS OSSIFEROUS ABILITY

Many kinds of materials are currently used as artificial bone substitutes. Hydroxyapatite (HA), the same as the main inorganic component of bone, is one of commonly used bio-ceramics and has excellent bioactivity and biocompatibility with hard tissues. However, it has problems as the bone filler or bone tissue-engineering scaffold due to low fracture toughness and low degradation rate. Recently, biodegradable materials for bone tissue have been developed to respond the requirement. Collagen, the same as the main organic component of bone, is biocompatible, biodegradable and promotes cell adhesion. A composites associated with HA is expected to have early osteoconduction and bone replacement ability. The present study was to fabricate bone-like composites consist of HA and collagen. Besides the ossiferous ability of the material in vivo is evaluated by using rabbits. Bone-like composites were successfully fabricated in this study, associating the collagen with HA. And the composites presented good osteoconductive and bone replacement potential.

DETERMINATION OF NINE COMPONENTS IN BAYER LIQUORS BY HIGH PERFORMANCE ION CHROMATOGRAPHY WITH CONDUCTIVITY DETECTOR

DETERMINATION OF NINE COMPONENTS IN BAYER LIQUORS BY HIGH PERFORMANCE ION CHROMATOGRAPHY WITH CONDUCTIVITY DETECTOR

In vivo aging of gutta‐percha dental cone

AbstractGutta‐percha cone is the most widely used material for root canal filling. The in vivo aging of this cone focus on the degradation of its main organic component, trans‐1,4‐polyisoprene, was studied. Aged cones (25 samples) from 2 to 30 years of root canal filling were extracted from different patients in the occasion of retreatment by mechanical way. The information about the aging time was given by the patients. Gel‐permeation chromatography (GPC) and infrared spectroscopy (FTIR) were the analytical techniques used. Polyisoprene degrades with time of aging, but in a slow process. Decrease in polymer molar mass from 5.7 × 105 to 1.7 × 105 g/mol was observed in polyisoprene from cone after 30 years of root canal filling and inside a noninfected tooth. In tooth with caries and periodontal infection, the decrease in molar mass is higher (4.6 × 104 g/mol in cone with 10 years of aging). The production of carbonyl and hydroxyl groups in the aged material indicates that the process is oxidative, even in closed teeth. In these cases, the oxygen could be provided from tissue fluid. The degradation mechanism is complex and depends on many factors, besides time of root canal filling. The dental problem caused by the aging could be the production and migration of cytotoxic substances to periodontal ligament and the reduction on the canal sealing property due to the polymer weight loss. Both of them could contribute to the root canal treatment failure. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:4082–4088, 2006

A Stepwise Stoichiometric Representation To Confirm the Dependence of Pesticide/Humic Acid Interactions on Salt Concentration and To Test the Performance of a Silica Bonded Humic Acid Column

In a previous paper (André et al., in press), a novel chromatographic column was developed in our laboratory for studying the binding of pesticides with humic acid (HA), the main organic component in soil. It was demonstrated that this column supported a low fraction of organic modifier in the aqueous mobile phase (<0.25 (v/v)). To overcome this limitation for a practical use, a column in which the stationary phase was based on silica gel with chemically bonded humic acid was created. It was shown that this novel HA column supported a higher methanol fraction (<0.55 (v/v)). As well, the dependence of pesticide/humic acid interactions on salt (sodium chloride) concentration has been expressed in terms of a stepwise stoichiometric representation, which leads to a specific equation for the partition of the added salt between the pesticide molecule, the HA, and the pesticide/HA complex. Based on this novel equation, the dependence of the pesticide/humic acid association on the salt concentration can be formulated via a relation similar to the one of Tanford. In addition, for the first time, the calculation of the affinity energy distribution for different values of the salt concentration in the mobile phase confirmed the existence of several types of binding sites on the HA macromolecule.

Inactivation of NADPH oxidase organizer 1 Results in Severe Imbalance

Otoconia are biominerals of the vestibular system that are indispensable for the perception of gravity. Despite their importance, the process of otoconia genesis is largely unknown. Reactive oxygen species (ROS) have been recognized for their toxic effects in antimicrobial host defense as well as in aging and carcinogenesis. Enzymes evolved for ROS production belong to the recently discovered NADPH oxidase (Nox) enzyme family . Here we show that the inactivation of a regulatory subunit, NADPH oxidase organizer 1 (Noxo1), resulted in the severe balance deficit seen in the spontaneous mutant "head slant" (hslt) mice whose phenotype was rescued by Noxo1 transgenes. Wild-type Noxo1 was expressed in the vestibular and cochlear epithelia and was required for ROS production by an oxidase complex. In contrast, the hslt mutation of Noxo1 was biochemically inactive and led to an arrest of otoconia genesis, characterized by a complete lack of calcium carbonate mineralization and an accumulation of otoconial protein, otoconin-90/95 (OC-90/95). These results suggest that ROS generated by a Noxo1-dependent vestibular oxidase are critical for otoconia formation and may be required for interactions among otoconial components. Noxo1 mutants implicate a constructive developmental role for ROS, in contrast to their previously described toxic effects.

Characterization of haloacetic acid precursors in source water

Raw water from the Bangkok (Thailand) main municipal water supply canal was examined for its natural organic composition by fractionation with adsorption resins. DAX-8 resin was the first resin employed to fractionate the hydrophobic fractions. Fractionation at neutral pH resulted in the separation of the hydrophobic neutral components; at a high pH level (approx. 10) separation of the hydrophobic base components occurred; and at a low pH level (approx. 2) the hydrophobic acid components were separated. AG-MP-50 cationic resin was then used to separate the hydrophilic base components, and WA-10, a weak anionic resin, was applied finally to fractionate the hydrophilic acid and neutral components. Subsequently, each fraction was tested for its chlorine disinfection by-product (DBP) formation potential. The HAA formation tests demonstrated that the various organic fractions had different reactivity levels for the formation of haloacetic acids (HAAs). For this source water, the hydrophilic neutral fraction dominated over the other five fractions in being the main organic component and the most significant precursor of HAAs formation. On the other hand, in terms of specific HAA formation potential (FP), the hydrophobic and hydrophilic base fractions were the most reactive precursors to the formation of HAAs. In all cases, the quantity of HAAs formed depended linearly upon the amount of organic constituents in the water sample.

Kinetics of Trihalomethane Formation From Organic Contaminants in Raw Water From the Bangkhen Water Treatment Plant*

The fractionation of raw water from Bangkhen water treatment plant, Bangkok, Thailand revealed that the mass distribution sequence of the six organic fractions from high to low was hydrophilic neutral (HPIN), hydrophobic acid (HPOA), hydrophilic acid, hydrophobic neutral, hydrophilic base, and hydrophobic base. The main organic matter components in raw water were HPIN and HPOA, which were also the two most important contributors of trihalomethane formation potential (THMFP). Linear dependencies between the level of each organic fraction and the formation potential of THM species were observed, which suggested the reactions between the organic fraction and chlorine during the chlorination were first order. The fractionation led to a deviation of bromide concentration in each organic fraction from the original concentration, and this affected the formation of brominated THM species. However, this effect was demonstrated to be within an acceptable range. The chlorination of an individual organic fraction resulted in a higher level of THMFP than that of the raw water and mixed fractions, indicating an inhibitory effect between the organic species. *Presented at “The 2nd Asian International Conference on Ecotoxicology and Environmental Safety” (SECOTOX 2004), Songkla, Thailand, 26–29 September 2004.

Intraneuronal investigations of organic components and trace elements with the use of synchrotron radiation

AbstractThree techniques based on synchrotron radiation microbeam analysis were applied to biochemical investigations of human central nervous system (CNS) tissue. Thin tissue slices representing Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and control cases were studied. Synchrotron radiation microbeam x‐ray fluorescence (micro‐SRXRF) was applied to the analysis of the elemental distribution inside single nerve cells. Investigation of copper oxidation state was performed with the use of micro x‐ray absorption near‐edge structure spectroscopy (micro‐XANES). Moreover, the organic components of the tissues were analyzed by means of synchrotron radiation Fourier transform infrared microspectroscopy (SR‐FTIRM). Topographic differences in elemental composition were observed for the nerve cell body. Higher levels of Fe, Zn and Ca were found for the neurons of PD cases in comparison with the control group. The IR spectra measured in neurons of PD, ALS and control cases showed differences in absorption bands associated with characteristic groups of selected biological molecules. Additionally, results of SR‐FTIRM measurements indicated inhomogeneous accumulation of the main organic components in PD nerve cells, in contrast to the control cases. Copyright © 2005 John Wiley &amp; Sons, Ltd.

Design of functionally graded dental implant in the presence of cancellous bone

In a previous work by the author [Hedia HS, Mahmoud NA. Biomed Mater Eng 2004;14(2):133--143], a functionally graded material (FGM) dental implant was designed without cancellous bone in the model. In this investigation, the effect of the presence of cancellous bone as a thin layer around the dental implant was investigated. It is well known that the main inorganic component of natural bone is hydroxyapatite (HAP) and that the main organic component is collagen (Col). HAP implants are not bioabsorbable, and because induction of bone into and around the artificially made HAP is not always satisfactory, loosening or breakage of HAP implants might occur after implantation in the clinical application. The development of a new material that is bioabsorbable and that has osteo-conductive activity is needed. Therefore, the aim of the current investigation was to design an implant, in the presence of cancellous bone as a thin layer around it, from FGM. In this study, a novel biomaterial, Col/HAP, as a FGM, was developed using the finite element and optimization techniques that are available in the ANSYS package. These materials have a self-organized character similar to that of natural bone. The investigations have shown that the maximum stress in the cortical bone and cancellous bone for the Col/HAP functionally graded implant has been reduced by about 40% and 19%, respectively, compared with currently used titanium dental implants.