Analysis of effect of nicotine on microbial community structure in sediment using PCR-DGGE fingerprinting

AbstractSolid or liquid waste containing a high concentration of nicotine can pollute sediment in rivers and lakes, and may destroy the ecological balance if it is directly discharged into the environment without any treatment. In this study, the polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) method was used to analyze the variation of the microbial community structure in the control and nicotine-contaminated sediment samples with nicotine concentration and time of exposure. The results demonstrated that the growth of some bacterial species in the nicotine-contaminated sediment samples was inhibited during the exposure. Some bacteria decreased in species diversity and in quantity with the increase of nicotine concentration or time of exposure, while other bacteria were enriched under the effect of nicotine, and their DGGE bands changed from undertones to deep colors. The microbial community structure, however, showed a wide variation in the nicotine-contaminated sediment samples, especially in the sediment samples treated with high-concentration nicotine. The Jaccard index was only 35.1% between the initial sediment sample and the sediment sample with a nicotine concentration of 0.030 μg/g after 28 d of exposure. Diversity indices showed that the contaminated groups had a similar trend over time. The diversity indices of contaminated groups all decreased in the first 7 d after exposure, then increased until day 42. It has been found that nicotine decreased the diversity of the microbial community in the sediment

Poly[[diaqua­hexa-μ-cyanido-cerium(III)ferrate(III)] dihydrate]

In the structure of the title complex, {[CeFe(CN)6(H2O)2]·2H2O}n, the CeIII and FeIII atoms exhibit square anti­prismatic [CeN6(H2O)2] (site symmetry m2m) and octahedral [FeC6] (site symmetry 2/m) coordination geometries, respectively. The metal atoms are linked alternately through the cyanide groups, forming a three-dimensional framework in which the {Ce2Fe2(CN)4} puckered square unit is the basic building block. The crystal packing is enforced by O—H⋯O and O—H⋯N hydrogen bonds, including the uncoordinated water molecule which is located on a mirror plane

Tris(1,10-phenanthrolin-1-ium) hexa­cyanidoferrate(III) ethanol monosolvate trihydrate

The asymmetric unit of the title complex, (C12H9N2)3[Fe(CN)6]·C2H5OH·3H2O, consists of two half [Fe(CN)6]3− anions located on inversion centers, three 1,10-phenanthrolin-1-ium cations, [Hphen]+, an ethanol and three water solvent mol­ecules. The average Fe—C and C—N bond lengths are 1.942 (6) and 1.154 (3) Å, respectively, while the Fe—C—N angles deviate slightly from linearity with values ranging from 177.8 (2) to 179.7 (2)°. The FeIII atoms adopt a distorted octa­hedral geometry. All the species are linked through O—H⋯N, N—H⋯O and O—H⋯O hydrogen-bonding inter­actions, resulting in a three-dimensional supra­molecular network