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 & Dielectric. 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.

Formulation and Evaluation of Solid Lipid Nanoparticles of a Water Soluble Drug: Zidovudine

Abstract: The present investigation was undertaken to develop solid lipid nanoparticles (SLN) of a hydrophilic drug Zidovudine (an anti-human immunodeficiency viral agent) and improve the entrapment efficiency of the drug in SLN. The SLN were prepared with stearic acid by process of w/o/w double-emulsion solvent-evaporation method using 3(2) factorial design. Different triglycerides alone and in different combinations, with/without stearic acid were used to prepare SLN using similar procedure. Two operating variables, polyvinyl alcohol concentration and amount of lipid were found to have significant effect on the particle size and entrapment efficiency (EE) of the SLN. The maximum EE was found to be ca. 27% with particle size of 621 nm which was significantly higher than that reported earlier. The optimized batch was also analyzed for its morphological, physiochemical and drug release properties. EE of batches with triglycerides were significantly less than that achieved with stearic acid alone. This work indicates the possible advantage of fatty acids over triglycerides in the entrapment of hydrophilic drugs in SLN.

Defense potential of secondary metabolites in medicinal plants under UV-B stress

Abstract: Ultraviolet-B (UV-B) radiation has, for many decades now, been widely studied with respect to its consequences on plant and animal health. Though according to NASA, the ozone hole is on its way to recovery, it will still be a considerable time before UV-B levels reach pre-industrial limits. Thus, for the present, excessive UV-B reaching the Earth is a cause for concern, and UV-B related human ailments are on the rise. Plants produce various secondary metabolites as one of the defense strategies under UV-B. They provide photoprotection via their UV-B screening effects and by quenching the reactive oxygen- and nitrogen species produced under UV-B influence. These properties of plant secondary metabolites (PSMs) are being increasingly recognized and made use of in sunscreens and cosmetics, and pharma- and nutraceuticals are gradually becoming a part of the regular diet. Secondary metabolites derived from medicinal plants (alkaloids, terpenoids, and phenolics) are a source of pharmaceuticals, nutraceuticals, as well as more rigorously tested and regulated drugs. These metabolites have been implicated in providing protection not only to plants under the influence of UV-B, but also to animals/animal cell lines, when the innate defenses in the latter are not adequate under UV-B-induced damage. The present review focuses on the defense potential of secondary metabolites derived from medicinal plants in both plants and animals. In plants, the concentrations of the alkaloids, terpenes/terpenoids, and phenolics have been discussed under UV-B irradiation as well as the fate of the genes and enzymes involved in their biosynthetic pathways. Their role in providing protection to animal models subjected to UV-B has been subsequently elucidated. Finally, we discuss the possible futuristic scenarios and implications for plant, animal, and human health pertaining to the defense potential of these secondary metabolites under UV-B radiation-mediated damages.

Isolation and characterization of bacterial endophytes of Curcuma longa L.

Abstract: Fourteen endophytic bacterial isolates were isolated from the rhizome of Curcuma longa L. were characterized on the basis of morphology, biochemical characteristics and 16S rRNA gene sequence analysis. The isolates were identified to six strains namely Bacillus cereus (ECL1), Bacillus thuringiensis (ECL2), Bacillus sp. (ECL3), Bacillus pumilis (ECL4), Pseudomonas putida (ECL5), and Clavibacter michiganensis (ECL6). All the strains produced IAA and solubilized phosphate and only two strains produced siderophore (ECL3 and ECL5) during plant growth promoting trait analysis. All the endophytic strains utilized glucose, sucrose and yeast extract as a carbon source where as glycine, alanine, cystine and glutamine as nitrogen source. The strains were mostly sensitive to antibiotic chloramphenicol followed by erythromycin while resistant to polymixin B. The endophytic strains effectively inhibit the growth of Escherichia coli, Klebsiella pneumoniae and some of the fungal strain like Fusarium solani and Alterneria alternata. The strain ECL2 and ECL4 tolerated maximum 8 % of NaCl concentration where as strains ECL5 and ECL6 6 % in salinity tolerance.

Sensitivity enhancement of surface plasmon resonance sensor based on graphene-MoS 2 hybrid structure with TiO 2 -SiO 2 composite layer

Abstract: In this paper, surface plasmon resonance (SPR) sensor based on graphene–MoS2 hybrid structure with composite layer of TiO2–SiO2 is presented. The angular interrogation method is used for the analysis of reflected light from the sensor. For the calculation of the sensitivity, first of all the thicknesses of TiO2, SiO2 and gold layers are optimized for the monolayer graphene and MoS2. Thereafter, at these optimum thicknesses the reflectance curves are plotted for different sensor structure and comparison of change in resonance angle is made among these structures. It is observed that the sensitivity of the graphene–MoS2-based sensor is enhanced by 9.24 % with respect conventional SPR sensor. The sensitivity is further enhanced by including TiO2–SiO2 composite layer between prism base and metal layer and observed that the enhanced sensitivity for this sensor is 12.82 % with respect to conventional SPR sensor and 3.28 % with respect to graphene–MoS2-based SPR sensor. At the end of this paper, the variation of the sensitivity and minimum reflectance is plotted with respect to sensing layer refractive index at the optimum thickness of all the layers and optimum number of MoS2 and graphene layers. It is also observed that four layers of MoS2 and monolayer graphene are best selection for the maximum enhancement of the sensitivity.