Luminescent Silver-Purine Double Helicate: Synthesis, Self-Assembly and Antibacterial Action.

Invited for this month's cover is the group of Prof. Sandeep Verma from the Indian Institute of Technology Kanpur, India. The cover picture shows the release of silver ions from silver-purine double helicate assembly that exhibits antibacterial activity against Gram-negative bacteria, E. coli. Read the full text of the article at 10.1002/cplu.201600293.

Luminescent Silver-Purine Double Helicate: Synthesis, Self-Assembly and Antibacterial Action.

The synthesis, self-assembly and antibacterial activity of a luminescent silver-purine double helicate is reported. The structure of the newly synthesized silver-supported helicate [C36 H24 N16 O4 Cl5 Ag1 ] was unambiguously characterized by single-crystal X-ray crystallography. It exhibited a bright bluish-green emission (λmax =460 nm), when excited with 380 nm light. Microscopic investigations showed that the complex has a propensity to self-assemble into nanospheres. The antibacterial activity of this silver-containing helicate was studied against both Gram-positive and Gram-negative bacteria. MIC (minimal inhibitory concentration) values showed that the complex is very active against Gram-negative bacteria. Further internalization of the silver complex into E. coli bacteria was mapped with the help of microscopic techniques. These results are significant as silver was recently found to enhance antibiotic action against Gram-negative bacteria, raising hope in countering severe bacterial infections.

Production of cellulase enzyme by Trichoderma reesei Cefl9 and its application in the production of bio-ethanol.

The present study aimed at the production of cellulase enzyme from the cellulolytic fungi Trichoderma reesei CEF19 and subsequent application of the cellulase for the fermentation of ethanol. For the same, the cellulolytic fungi, Trichoderma reesei CEF19 was isolated and was allowed to produce cellulase enzyme using optimized conditions. The cellulase enzyme was extracted and purified with the help of ammonium sulphate precipitation, dialysis followed by ion exchange chromatography with DEAE-Sephadex column. The purified cellulase enzyme was characterized using SDS-PAGE analysis. The saccharification of the cellulosic substrates was done using the cellulase enzyme. The fermentation of saccharified cellulosic substrates into ethanol was carried out using Saccharomyces cerevisiae. From the results obtained, rice straw was found to be the better source for the ethanol production when compared to the other substrates.