Banaras Hindu University

About: Banaras Hindu University is a education organization based out in Varanasi, Uttar Pradesh, India. It is known for research contribution in the topics: Population & Catalysis. The organization has 11858 authors who have published 23917 publications receiving 464677 citations. The organization is also known as: Kashi Hindu Vishvavidyalay & Benares Hindu University.

Ultraviolet radiation and cyanobacteria.

Abstract: Cyanobacteria are the dominant photosynthetic prokaryotes from an ecological, economical, or evolutionary perspective, and depend on solar energy to conduct their normal life processes. However, the marked increase in solar ultraviolet radiation (UVR) caused by the continuous depletion of the stratospheric ozone shield has fueled serious concerns about the ecological consequences for all living organisms, including cyanobacteria. UV-B radiation can damage cellular DNA and several physiological and biochemical processes in cyanobacterial cells, either directly, through its interaction with certain biomolecules that absorb in the UV range, or indirectly, with the oxidative stress exerted by reactive oxygen species. However, cyanobacteria have a long history of survival on Earth, and they predate the existence of the present ozone shield. To withstand the detrimental effects of solar UVR, these prokaryotes have evolved several lines of defense and various tolerance mechanisms, including avoidance, antioxidant production, DNA repair, protein resynthesis, programmed cell death, and the synthesis of UV-absorbing/screening compounds, such as mycosporine-like amino acids (MAAs) and scytonemin. This study critically reviews the current information on the effects of UVR on several physiological and biochemical processes of cyanobacteria and the various tolerance mechanisms they have developed. Genomic insights into the biosynthesis of MAAs and scytonemin and recent advances in our understanding of the roles of exopolysaccharides and heat shock proteins in photoprotection are also discussed.

A highly sensitive and selective fluorescent sensor for Al3+ ions based on thiophene-2-carboxylic acid hydrazide Schiff base

Abstract: An efficient fluorescent receptor (E)-N-[(2-hydroxy-naphthalen-1-yl)methylene]thiophene-2-carbohydrazide (THN) for Al3+ ions was synthesized and characterized by physicochemical and spectroscopic tools along with single crystal X-ray crystallography. This is the first report showing the crystal structure of THN and its sensing property for Al3+ ions. THN selectively and sensitively detects Al3+ ions without any interference among various cations, Na+, K+, Ca2+, Cr3+, Mg2+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+ and Hg2+ by a strong fluorescent change in ethanol–water medium (EtOH–H2O, 1 : 4 v/v). The THN interacts with Al3+ in a tridentate mode to form a [AlCl2(THN)(H2O)]·H2O complex. The binding constant was determined to be 7.06 × 106 M−1 and the limit of detection (LOD) was calculated to be 1.35 × 10−9 M which is the second highest reported till date in the literature. The 1H NMR titration, ESI-MS and DFT studies have also been performed in support of the binding details of the THN–Al3+ complex.

Agrobacterium-mediated transformation of cauliflower: optimization of protocol and development of Bt-transgenic cauliflower.

Abstract: A number of factors that are known to influence genetic transformation were evaluated to optimizeAgrobacterium-mediated transformation of hypocotyl explants of cauliflower variety Pusa Snowball K-1. The binary vector p35SGUSINT mobilized intoAgrobacterium strain GV2260 was used for transformation and transient GUS expression was used as the basis for identifying the most appropriate conditions for transformation. Explant age, preculture period, bacterial strain and density were found to be critical determinants of transformation efficiency. Using the optimized protocol, the syntheticcryIA(b) gene was mobilized into cauliflower. Molecular analyses of transgenics established the integration and expression of the transgene. Insect bioassays indicated the effectiveness of the transgene against infestation by diamondback moth (Plutella xylostella) larvae.