4-[3,5-Bis(ethoxy­carbon­yl)-2,6-dimethyl-4-pyrid­yl]pyridinium nitrate

In the title mol­ecular salt, C18H21N2O4 +·NO3 −, the dihedral angle between the two pyridine rings is 61.24 (8)°. In the crystal, the cation and anion are linked by inter­molecular N—H⋯O hydrogen bonds

Diethyl 2,6-dimethyl-4-(4-pyrid­yl)-1,4-dihydro­pyridine-3,5-dicarboxyl­ate

In the title compound, C18H22N2O4, the dihedral angle between the two rings is 87.90 (6)°. The mean devation of the atoms in the dihydropyridine plane is 0.082 (3) Å. In the crystal, mol­ecules are linked by inter­molecular N—H⋯N hydrogen bonds, generating chains

Detection of Microcystin-Producing Cyanobacteria in a Reservoir by Whole Cell Quantitative PCR

AbstractCyanobacterial blooms are of increasing concern due to their negative impacts on environment and cyanobacteria-producing cyanotoxins, which create serious threats to animal and human health. Early detection of the harmful cyanotoxin-producing cyanobacteria is vital for the water management. In this study, we compared the amplification specificity for microcystin-producing cyanobacteria with primers targeting 16S rRNA genes, phycocyanin operon, and regions of mcy gene clusters. To detect presence of microcystin-producing cyanobacteria in a drinking water sourced reservoir, whole cell PCR assay was performed to amplify partial mcyA, mcyE, and the results were compared with that of direct microscopic counts based on morphologic identification. The positive liner correlation of the Microcystis colony by microscopic counts with mcyA containing cell, which was quantified by whole cell quantitative RT-PCR assay, was further confirmed. The results indicated that the microcystin-producer in the reservoir was mainly Microcystis. Therefore, we provided a simple, rapid, sensitive and applicable method for early detection of toxic cyanobacteria

Metal adsorption by quasi cellulose xanthogenates derived from aquatic and terrestrial plant materials

The FTIR spectra, SEM-EDXA and copper adsorption capacities of the raw plant materials, alkali treated straws and cellulose xanthogenate derivatives of Eichhornia crassipes shoot, rape straw and corn stalk were investigated. FTIR spectra indicated that of the three plant materials, the aquatic biomass of Eichhornia crassipes shoot contained more O-H and C=O groups which accounted for the higher Cu²⁺ adsorption capacities of the raw and alkali treated plant material. SEM-EDXA indicated the incorporation of sulphur and magnesium in the cellulose xanthogenate. The Cu²⁺ adsorption capacities of the xanthogenates increased with their magnesium and sulphur contents. However more copper was adsorbed than that can be explained by exchange of copper with magnesium. Precipitation may contribute to the enhanced uptake of copper by the cellulose xanthogenate