Balance of glucosinolates content under Cd stress in two Brassica species.

We designed a pot experiment to study the changes of growth parameters, accumulation of Cd in cabbage and kale, during a prolonged exposure period with two harvests (after 45 and 75 days of plant growth). Simultaneously, we monitored changes of total S and GSL contents in different plant organs. Both Brassica species showed tolerance to Cd, since no obvious symptoms of metal toxicity were displayed and no significantly reduced plant biomass were recorded. Moreover, a trend of root biomass enhancement was noticed. In general, the Cd concentration in roots was higher than in other organs. Data indicate that the transport system from roots to shoots was already saturated after the first growing period, while root continued to accumulate Cd during the second growing period. Regardless of differences in the GSL content between cabbage and kale, both Brassica species had a similar response to Cd exposure, indicating that the Brassicacea plant family could have unique features for the regulation of GSL content in order to balance the roles of GSLs as defence compounds and as S reservoirs. During the first growing period, GSLs in leaves and root could be more involved in ameliorating S deficiency rather than plant defence. After long-term Cd exposure, we found differences between GSL patterns in leaves and root. Furthermore, we found increased total GSL levels in the stem during whole experiment which indicates that stem could serve as a GSLs storage organ under Cd stress. This paper provides new insight into the possible roles of GSL in Cd stress.

Cytotoxic effects of imidazolium ionic liquids on fish and human cell lines.

Ionic liquids bring a promise of a wide range of "green" applications that could replace conventional volatile solvents. However, before these applications become large-scale, their toxicity needs to be investigated in order to predict the impact on human health and environment. In this study we assessed the cytotoxicity of imidazolium ionic liquids (in the concentrations between 0.1 mmol L-1 and 10 mmol L-1) in the ovarian fish cell line CCO and the human tumour cell line HeLa using the MTT cell viability assay. Our results showed that the most cytotoxic ionic liquid was 1-n-butyl-3-methylimidazolium bis(trifluoro methylsulphonyl)imide, [BMIM][Tf2N], followed by 1-n-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4], 1-n-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6], and 1,3-dimethylimidazolium hexafluorophosphate [MMIM][PF6]. Generally, the effects were concentration-dependent. They also depended on the type of anion and the n-alkyl chain length. The comparison between the fish CCO and human HeLa cell lines suggests that CCO cells provide a good biological system for initial toxicity testing of ionic liquids that could replace in vivo bioassays.

N-(o-chlorophenyl)-2,5-dimethylpyrrole-3-carbaldehyde.

Crystal structure analysis of the title compound, C(13)H(12)ClNO, reveals three crystallographically independent molecules in the asymmetric unit. The main conformational difference between these molecules is the orientation of the phenyl rings with respect to the pyrrole rings. The coplanar arrangement of the aldehyde groups attached to the pyrrole rings influences the pyrrole-ring geometry. The C2-C3 and N1-C5 bonds are noticeably longer than the C4-C5 and N1-C2 bonds. Two independent molecules of the title compound form dimers via intermolecular C-H.O hydrogen bonds [D.A = 3.400 (3) A and D-H.A = 157 degrees ]. The perpendicular orientation of the phenyl and pyrrole rings of one independent molecule and its symmetry-related molecule allows C-H.pi interactions, with an H.centroid distance of 2.85 A and a C-H.pi angle of 155 degrees. The distances between the H atom and the pyrrole-ring atoms indicate that the C-H bond points towards one of the bonds in the pyrrole ring.