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Oxyfunctionalization of plant oils such as olive oil and soybean oil into C9 carboxylic acids (e.g., n-nonanoic acid and 9-hydroxynonanoic acid) was investigated. The biotransformation was composed of hydrolysis of plant oils by the Thermomyces lanuginosus lipase (TLL) and C9–C10 double-bond cleavage in unsaturated fatty acids by a serial reaction of a fatty acid double bond-hydratase of Stenotrophomonas maltophilia, an alcohol dehydrogenase of Micrococcus luteus, and a Baeyer–Villiger monooxygenase (BVMO) of Pseudomonas putida KT2440 expressed in Escherichia coli. The newly cloned oleate hydratase allowed one to produce 10-hydroxyoctadecanoic acid and 10-hydroxyoctadec-12-enoic acid at a high rate from oleic acid and linoleic acid, respectively, which are major fatty acid constituents of many plant oils. Furthermore, overexpression of a long chain fatty acid transporter FadL in the recombinant E. coli led to a significant increase of whole-cell biotransformation rates of oleic acid and linoleic acid into...

Whole-cell biotransformation of fatty acids can be influenced by the activities of catalytic enzymes and by the efficiency of substrate transport into host cells. Here, we improved fatty acid hydration activity of the recombinant Escherichia coli expressing an oleate hydratase of Stenotrophomonas maltophilia by targeting the catalytic enzyme into the periplasm instead of the cytoplasm. Recombinant E. coli producing OhyA in the periplasm under guidance of the PelB signal sequence (E. coli OhyA_PP) exhibited significantly greater hydration activity with oleic acid and linoleic acid compared to a recombinant E. coli producing OhyA in the cytoplasm (E. coli OhyA_CS). For example, the oleate double bond hydration rate of E. coli OhyA_PP was >400 μmol/g dry cells/min (400 U/g dry cells), which is >10-fold higher than that of E. coli OhyA_CS. As the specific activities of the enzymes targeted into the cytoplasm and periplasm were comparable, we assumed that targeting OhyA into the periplasm could accelerate fatty acid transport to the catalytic enzymes by skipping the major mass transport barrier of the cytoplasmic membrane. Our results will contribute to the development of whole-cell biocatalysts for fatty acid biotransformation.

Hydroxy fatty acids are used as starting materials for the production of secondary metabolites and signalling molecules as well as in the manufacture of industrial fine chemicals. However, these compounds are usually difficult to produce from renewable biomass by chemical means. In this study, linoleate double bond hydratases of Lactobacillus acidophilus NBRC 13951 were cloned for the first time. These enzymes were highly specific for the hydration of the C-9 or the C-12 double bond of unsaturated fatty acids (e.g., linoleic acid). Thereby, the enzymes allowed the selective production of hydroxy fatty acids such as 13-hydroxy-cis-9-octadecenoic acid and 10-hydroxy-cis-12-octadecenoic acid from linoleic acid. In addition, the hydroxy fatty acids were further converted into industrially relevant carboxylic acids (e.g., 12-hydroxy-cis-9-dodecenoic acid, α,ω-tridec-9-enedioic acid) and lactones (i.e., δ-decalactone, γ-dodecelactone) via whole-cell biocatalysis using an enzyme cascade. This study thus contributes to the preparation of hydroxy fatty acids, unsaturated carboxylic acids, and lactones from renewable unsaturated fatty acids.

Oils and fatty acids are important renewable resources provided by nature. Therefore, biotransformation of renewable oils and fatty acids into industrially relevant C9 chemicals was investigated in this study. Olive oil, soybean oil, yeast derived oil, and microalgae fatty acid methyl esters were converted into n-nonanoic acid, 9-hydroxynonanoic acid, and 1,9-nonanedioic acid by a lipase and a recombinant Escherichia coli expressing oleate hydratase, long chain secondary alcohol dehydrogenase, Baeyer-Villiger monooxygenase, long chain primary alcohol dehydrogenase, and aldehyde dehydrogenase. It was found that n-nonanoic acid and azelaic acid could be produced to a concentration of 4.3 mM from 3 g/L olive oil with a specific product formation rate of 3.1 U/g dry cells. Biotransformation rates were influenced by compositions of fatty acids and purity of the starting material. This study may contribute to the production of industrially relevant C9 chemicals from renewable oils and fatty acids by simultaneous enzyme/whole-cell biotransformation.

Backgrounds The association of dietary vitamin C (vit C) on periodontitis requires more valid evidence from large representative samples to enable sufficient adjustments. This study aimed to evaluate the association between dietary vit C intake and periodontitis after controlling for various confounders in the representative Korean adult population Method A total of 10,930 Korean adults (≥19 years) from the fourth Korean National Health and Nutrition Examination Survey data set were included in this cross-sectional study. Periodontitis was defined as community periodontal index score of 3 or 4. Dietary vit C intake was estimated from a 24-hour dietary record, and categorized into adequate and inadequate according to the Korean Estimated Average Requirement value. Potential confounders included age, sex, income, frequency of tooth brushing, use of floss, dental visit, drinking, smoking, diabetes, hypercholesterolemia, hypertension, and obesity. A multivariable logistic regression analysis and stratified analysis were applied. Results Those with inadequate dietary vit C intake were more likely by 1.16 times to have periodontitis than those with adequate dietary vit C intake (adjusted odds ratio [aOR] = 1.16, 95% confidence interval = 1.04–1.29). Lowest and middle-low quartile of dietary vit C intake, compared to highest quartile of dietary vit C intake, showed significant association (aOR = 1.28 and 1.22 respectively), which was in a biological-gradient relationship (trend-p

Biotransformation of long-chain fatty acids into medium-chain α,ω-dicarboxylic acids or ω-aminocarboxylic acids could be achieved with biocatalysts. This study presents the production of α,ω-dicarboxylic acids (e.g., C9, C11, C12, C13) and ω-aminocarboxylic acids (e.g., C11, C12, C13) directly from fatty acids (e.g., oleic acid, ricinoleic acid, lesquerolic acid) using recombinant Escherichia coli-based biocatalysts. ω-Hydroxycarboxylic acids, which were produced from oxidative cleavage of fatty acids via enzymatic reactions involving a fatty acid double bond hydratase, an alcohol dehydrogenase, a Baeyer–Villiger monooxygenase and an esterase, were then oxidized to α,ω-dicarboxylic acids by alcohol dehydrogenase (ADH, AlkJ) from Pseudomonas putida GPo1 or converted into ω-aminocarboxylic acids by a serial combination of ADH from P. putida GPo1 and an ω-transaminase of Silicibacter pomeroyi. The double bonds present in the fatty acids such as ricinoleic acid and lesquerolic acid were reduced by E. coli-native enzymes during the biotransformations. This study demonstrates that the industrially relevant building blocks (C9 to C13 saturated α,ω-dicarboxylic acids and ω-aminocarboxylic acids) can be produced from renewable fatty acids using biocatalysis.

The generation of staurolite from the mixed-phase muscovite and the metamorphic environment of shales in the Baekunsa formation, Hongsan, Buyeo, were studied using electron probe micro analysis (EPMA). The average chemical composition of mica-type mineral is , and shows a characteristics of the so-called illite with a low content of interlayer cations and Fe, Mg in octahedral sites. The mica-type mineral shows a typical chemical composition of the mixed-phase among muscovite, pyrophyllite, and chlorite (mixed-phase muscovite, ). The staurolite, in general, occurs with the mixed-phase muscovites, pyrophyllites, and aluminosilicates in the rock. We consider that staurolite can be formed by a reaction involving pyrophyllite such as pyrophyllite+chloritoid. The chloritoid is formed by a reaction between pyrophyllite and chlorite and is supposed to be used up in the process of staurolite formation. As a result, the mixed-phase muscovite, formed during the transition of illite to muscovite, plays an important role for the generation of the staurolite. Considering that the reaction occurs at the temperature higher than and pyrophyllites transform into aluminosilicates at , the shale in the Baekunsa formation can be considered to have been experienced a metamorphic temperature between .

Microbial hydroxylation of long chain fatty acids has been extensively investigated. However, biotransformation productivity remains below ca. 1.0 g/g cell dry weight (CDW)/h under process conditions. In the present study, a highly efficient microbial hydroxylation process to convert oleic acid into 10-hydroxystearic acid was developed. A recombinant Escherichia coli expressing ohyA, the gene encoding oleate hydratase of Stenotrophomonas maltophilia, was used as the biocatalyst. Investigation of the ohyA expression and biotransformation conditions (e.g., inducer concentration, gene expression period before initiating biotransformation, mixing condition of reaction medium) enabled 10-hydroxystearic acid to accumulate to a final concentration of approximately 46 g/L in the culture medium. The specific product formation rate and product yield reached approximately 2.0 g/g CDW/h (i.e., 110 U/g CDW) and 91%, respectively. The specific product formation rate was more than 3-fold higher than those of a bioprocess using wild type Stenotrophomonas sp. cells. Additionally, the product of the whole-cell biotransformation was recovered at a yield of 70.9% and a purity of 99.7% via solvent fraction crystallization at low temperature. These results will contribute to developing a biological process for hydroxylation of oleic acid.

Structural and compositional properties of ferritin cores were studied by transmission electron microscopy (TEM) and inductively coupled plasma (ICP) spectrometry. The native tadpole ferritin (TdF) contains 880 Fe atoms per molecule of protein and considerable amounts of phosphate (Fe:Pi=5.2). The core size of TdF is 6.75 (±0.72) nm. In the ferritin reconstituted with 1170 Fe atoms per molecule of protein, the core size is 8.31 (±0.97) nm. Electron diffraction patterns of both native and reconstituted tadpole ferritins show poor crystallinity, giving diffuse diffraction lines. Both ferritin cores were identified as ferrihydrite. Reconstituted iron cores of recombinant tadpole H-chain ferritin produced in Escherichia coli contain 1280 Fe atoms and show similar crystallinity with the size of 8.08 (±0.90) nm.

A highly robust gap-fill process technology of spin-on glass (SOG) was developed for the interlayer dielectric (ILD) in sub-30nm devices. We revealed that the filling behavior of SOG within gaps during spin-coating is mainly dependent on the capillary effect. The highly wettable surface treatment prior to SOG coating was found to enhance the gap-fill performance remarkably. This technique plays a key role in maximizing capillary effect by raising surface wettability. The filling capability was also improved by optimization of baking temperature to minimize the viscosity of SOG. It was finally found that the defects of contact bridges due to poor filling of SOG were reduced to be almost free by those unique process refinements.

Incorporation of metal nanoparticles in Polyaniline composites could effectively improve its optical, thermal and electrical properties and making it an ideal for the use in semiconductor industry. In this study Ag nanoparticles were uniformly dispersed ultrasonically in the solution of polyaniline emeraldine base (PANIEB) and isopropyl alcohol. PANIEB used in this experiment were doped with polymer of methacrylic acid ester and vinyl verstate. The results about the morphological, optical and electrical properties of Ag-PANIEB with IPA colloid as a function of different concentration of Ag nanoparticles (Such as 25%, 50%, 100% by weight) were presented and discussed.

Treatment ofsmectite with laurylamine hydrochloride was verified to cause expansion of d(001) which may be retained and observed in ion-milled samples by transmission electron microscopy. The spacings between layers as observed in lattice fringe images, however, are variable and may be as small as 10 A. The method therefore produces ambiguities in differentiating between some smectites and illites, similar to those that have been found for untreated samples; e.g., on this basis, expanded layers may be inferred to be smectite, but layers with d-values approaching 10  may be either illite or smectite. Expansion also destroys the original rock texture, which, therefore, must be observed using only untreated samples.

Diffusion of K during analytical electron microscopy (AEM) results in anomalously low count rates for this element. As the analysis area and specimen thickness decrease, count rates become dispro- portionally lower. Adularia and muscovite show different diffusion profiles during AEM; for muscovite a strong dependence of diffusion on crystallographic orientation has been observed. Conditions giving rise to reliable chemical data by AEM are the use of a wide scanning area (>800 x 800 A) and/or large beam size to reduce the effect of diffusion of alkali elements, a specimen thickness greater than about 1000 ~, constant instrument operating conditions, and the use of a homogeneous, well-characterized standard sample. The optimum thickness range was obtained by determining the element intensity ratio vs. thickness curve for given operating conditions. The standard and unknown should have a similar crystal structure and, especially for strongly anisotropic minerals such as phyllosilicates, a similar crys- tallographic orientation with respect to the electron beam.

Phyllosilicates in rocks which are transitional from mudstone to slate from Lehigh Gap, Pa., have been studied by a variety of techniques, including high resolution Transmission Electron Microscopy and Analytical Electron Microscopy. The principal minerals are “white mica” which is transitional from illite in mudstone to ordered twolayer mica in slate, and chlorite. 7A berthierine occurs more rarely. Dioctahedral and trioctahedral layers are shown to be interleaved in individual crystals at all scales between the following two end members: (1) both random and regular 1∶1 interlayering at the scale of individual layers, as shown, in part, by lattice fringe images. (2) packets of trioctahedral and dioctahedral layers up to a few thousand Angstroms or microns in thickness, detectable with ordinary optical techniques. The complete range of intermediate structures is represented in samples which are in transition to slate. Bulk analytical (EMPA), X-ray diffraction or other measurements are shown to result in averages over both kinds of layers when TEM techniques are not used.

Phyllosilicates that occur in shales and slates show complex features as generally detected by methods such as X-ray diffraction. Diffraction patterns commonly display features such as broadened and asymmetric peaks which in many cases have been shown to reflect random interlayering of more than one kind of phyllosilicate1; for example, illite–smectite and vermiculite–chlorite. Ordered interlayering of more than one phase has also been frequently observed. However, powder diffraction data generally provide insight only into the differences between units of many layers and then they only yield average values. The possibility of variations within individual layers can be investigated using transmission electron microscopy (TEM) and analytical electron microscopy (AEM). We report here on the occurrence of transitions within individual phyllosilicate layers from one trioctahedral structure to another (ferroan lizardite to chlorite) and from trioctahedral to dioctahedral (illite) layers. These variations in structure introduce a new range of complexities into those non-equilibrium phyllosilicate structures which occur in low-temperature sedimentary environments.