Feasibility study of a pilot-scale sewage treatment system combining an up-flow anaerobic sludge blanket (UASB) and an aerated fixed bed (AFB) reactor at ambient temperature

A feasibility test of a 17 m3-pilot-scale sewage treatment system was carried out by continuous feeding of raw municipal sewage under ambient temperature conditions. The system consisted of a UASB and an aerated fixed bed reactor. Some of the effluent from the fixed bed reactor was returned to the UASB influent in order to provide a sulfate source. The total BOD of 148-162 mg l(-1) in the influent was reduced to a more desirable 11-25 mg l(-1) in the final effluent. The levels of methane-producing activity from acetate and H2/CO2 gas at 10 degrees C were only 2% and 0% of those at 35 degrees C, respectively. On the other hand, the sulfate-reducing activity levels of the UASB sludge were relatively high at 10 degrees C, for example, 18% for acetate and 9% for H2/CO2 gas, compared to the activity levels at 35 degrees C. Therefore, BOD oxidization by sulfate reduction in the UASB was greater than that by methane production under low temperature conditions. This sulfate-reducing activity tended to be proportional to the copy number of adenosine-5'-phosphosulfate (APS) reductase genes in DNA extracted from the sludge.     

Cyclodextrin-linked alginate beads as supporting materials for Sphingomonas cloacae, a nonylphenol degrading bacteria

Calcium alginate beads covalently linked with alpha-cyclodextrin (alpha-CD-alginate beads) were prepared and examined for their ability to serve as a supporting matrix for bacterial degradation of nonylphenol, an endocrine disruptor. Column chromatographic experiment using alpha-CD-alginate beads with diameter of 657+/-82 microm and with degree of CD substitution of 0.16 showed a strong affinity for nonylphenol adsorption. Although addition of alpha-CD (2.7-27 mM) to the culture broth of Sphingomonas cloacae retarded nonylphenol degradation, the immobilized bacteria on the CD-alginate beads were effective for the degradation. Batch degradation tests using the immobilized bacteria on alpha-CD-alginate-beads showed 46% nonylphenol recovery after 10-day incubation at 25+/-2 degrees C, and the recovery reached to about 17% when wide and shallow incubation tubes were used to facilitate uptake of the viscous liquid of nonylphenol on the surface of the medium. Scanning electron microscopic photographs revealed that multiplicated bacteria was present both on the surface and inside the beads and the matrix of CD-alginate was stable and suitable during 10-day incubation.     

Immunohistochemical detection of hypoxia in mouse liver tissues treated with pimonidazole using “in vivo cryotechnique”

To evaluate hypoxic cells in live mouse liver tissues, immunohistochemistry for protein adducts of reductively activated pimonidazole (PARaPi) was performed using the “in vivo cryotechnique (IVCT)” followed by freeze-substitution fixation. This method was used because cryotechniques have some merits for examining biological events in living animal organs with improved time-resolution compared to conventional perfusion and/or immersion chemical fixation. Pimonidazole was intraperitoneally injected into living mice, and then after various times of hypoxia, their livers were quickly frozen by IVCT. The frozen liver tissues were freeze-substituted in acetone containing 2% paraformaldehyde, and routinely embedded in paraffin wax. De-paraffinized sections were immunostained for PARaPi. In liver tissues of mice without hypoxia, almost no immunostained cells were detected. However, in liver tissues with 30 s of hypoxia, some hepatocytes in the pericentral zones were strongly immunostained. After 60 s of hypoxia, many hepatocytes were immunostained with various degrees of staining intensity in all lobular zones, indicating different reactivities of pimonidazole in the hepatocytes to hypoxia. At this time, the general immunoreactivity also appeared to be stronger around the central veins than other portal areas. Although many hepatocytes were immunostained for PARaPi in the liver tissues with perfusion fixation via heart, those with perfusion via portal vein were not immunostained. Thus, IVCT is useful to detect time-dependent hypoxic states with pimonidazole treatment in living animal organs.     

In situ observation of spherical DNA assembly in water and the controlled release of bound dyes

Three strands of 30-mer oligodeoxyribonucleotides (ODNs) were designed to form three-way junctions that possess self-complementary sticky ends. The morphology of self-assembled ODNs in water was observed in situ by confocal laser scanning fluorescence microscopy. The three-way junctions self-assembled into spherical assemblies, in accordance with transmission and scanning electron microscopy. The size of nucleospheres was in the range of several tens of nanometers to micrometers, which varied depending on the concentration of ODNs and added salts. Fluorescence images of spherical ODN assemblies suggested that the nucleospheres possess multiwalled structures. The fluorescence of sodium 1-anilinonaphthalene-8-sulfonate in the presence of nucleospheres revealed that the interior of nucleospheres possesses polarity corresponding to that between methanol and ethanol. A dye-inclusion experiment showed that cationic and even anionic dyes were adsorbed to the interior of the nucleospheres. The dye-included nucleospheres released dyes by thermal dissociation or digestion of the constituent ODNs.     

Simultaneous Enantioseparation of Aldohexoses and Aldopentoses Derivatized With L‐Tryptophanamide by Reversed Phase HPLC Using Butylboronic Acid as a Complexation Reagent of Monosaccharides

Three aldohexoses, glucose, galactose, and mannose, and three aldopentoses, arabinose, xylose, and ribose, were derivatized with L‐tryptophanamide (L‐TrpNH₂) under alkaline conditions. Using a basic mobile phase (pH 9.2), the three aldohexoses or the three aldopentoses were simultaneously enantioseparated, respectively, but all the six monosaccharides could not be simultaneously enantioseparated. A large amount of nonreacted L‐TrpNH₂ was detected after the derivatized monosaccharides. In order to widen the separation window, a large portion of nonreacted L‐TrpNH₂ could be eliminated by liquid–liquid extraction with ethylacetate, and elution order of the derivatized monosaccharides and nonreacted L‐TrpNH₂ was found to be reversed using a neutral mobile phase. All of the six monosaccharides were simultaneously enantioseparated by reversed phase high‐performance liquid chromatography (HPLC) using InertSustainSwift C18 column (4.6 mm i.d. × 150 mm) and a mobile phase containing 180 mM phosphate buffer (pH 7.6), 1.5 mM butylboronic acid, and 5% acetonitrile at 40 °C. Nomenclature of D and L for monosaccharides is based on the configurations of the asymmetric C4 center for aldopentoses and C5 center for aldohexoses. It was found that the enantiomer elution order of these six monosaccharides and fucose in the proposed method conformed to be the absolute configuration of the C2 center. Chirality 27:417–421, 2015. © 2015 Wiley Periodicals, Inc.     

New silica monolith bonded chiral (R)‐γ butyrolactone for enantioselective micro high‐performance liquid chromatography

A single low‐molecular mass chiral selector namely (R)‐acryloyloxy‐β‐β‐dimethyl‐γ‐butyrolactone has been bonded to a modified silica‐based monolith to form a new brush‐type chiral stationary phase for micro‐high performance liquid chromatography (HPLC) separation. © 2011 Wiley‐Liss, Inc.     

Melanin biosynthesis inhibitors from Tarragon Artemisia dracunculus

The EtOH extract of tarragon Artemisia dracunculus, a perennial herb in the family Asteraceae, was found to potently inhibit α-melanocyte-stimulating hormone (α-MSH) induced melanin production in B16 mouse melanoma cells. Bioassay-guided fractionation led to the isolation of two alkamide compounds, isobutyl (1) and piperidiyl (2) amides of undeca-2E,4E-dien-8,10-dynoic acid. The respective EC(50) values for melanin biosynthesis inhibition were 1.8 and 2.3 μg/mL for 1 and 2.     

5a-Carba-β-D-glucopyranose derivatives as novel sodium-dependent glucose cotransporter 2 (SGLT2) inhibitors for the treatment of type 2 diabetes

5a-Carba-β-D-glucopyranose derivatives were synthesized and identified as novel SGLT2-selective inhibitors. These inhibitors exhibited potent SGLT2 inhibition with high selectivity over SGLT1. Among the tested compounds, 6f indicated the most potent hSGLT2 inhibition and the highest selectivity over hSGLT1. Moreover, the pharmacokinetics data also showed that 6h, which had the same aglycon structure as sergliflozin-active (3-active), had a threefold longer half-life time (T(1/2)) than sergliflozin (3) with a high distribution volume in db/db mice. Subsequently, 6h lowered blood glucose levels as much as 3 and showed longer hypoglycemic action than 3 in db/db mice.