North Eastern Hill University

About: North Eastern Hill University is a education organization based out in Shillong, Meghalaya, India. It is known for research contribution in the topics: Population & Catalysis. The organization has 2318 authors who have published 4476 publications receiving 48894 citations.

Resequencing of global Tartary buckwheat accessions reveals multiple domestication events and key loci associated with agronomic traits

Abstract: Tartary buckwheat (Fagopyrum tataricum) is a nutritionally balanced and flavonoid-rich crop plant that has been in cultivation for 4000 years and is now grown globally. Despite its nutraceutical and agricultural value, the characterization of its genetics and its domestication history is limited. Here, we report a comprehensive database of Tartary buckwheat genomic variation based on whole-genome resequencing of 510 germplasms. Our analysis suggests that two independent domestication events occurred in southwestern and northern China, resulting in diverse characteristics of modern Tartary buckwheat varieties. Genome-wide association studies for important agricultural traits identify several candidate genes, including FtUFGT3 and FtAP2YT1 that significantly correlate with flavonoid accumulation and grain weight, respectively. We describe the domestication history of Tartary buckwheat and provide a detailed resource of genomic variation to allow for genomic-assisted breeding in the improvement of elite cultivars.

Kinetic parameters for nutrient enhanced crude oil biodegradation in intertidal marine sediments.

Abstract: Availability of inorganic nutrients, particularly N and P, is often a primary control on crude oil hydrocarbon degradation in marine systems. Nevertheless, there is a paucity of information on fundamental kinetic parameters for nutrient enhanced crude oil biodegradation that can be used to model the fate of crude oil in bioremediation programmes that use inorganic nutrient addition to stimulate oil biodegradation. Here we report fundamental kinetic parameters (Ks and qmax) for nitrate- and phosphate-stimulated crude oil biodegradation under nutrient limited conditions and with respect to crude oil, under conditions where N&P are not limiting. Crude oil degradation was limited by both N&P availability. When N was added alone maximum rates of CO2 production measured were 3.94±0.46 µmol CO2 /g wet sediment/day. However when the same levels of N were added in the presence of 0.5% P w/w of oil (1.6 μmol P/g wet sediment) maximum rates of measured CO2 production more than doubled (11.52±0.72 µmol CO2 /g wet sediment/day). Ks and qmax estimates for N (in the form of sodium nitrate) when P was not limiting were 1.57±0.56 µmol/g wet sediment and 10.57±0.63 µmol CO2 /g wet sediment/day respectively. The corresponding values for P were 80 nmol/g wet sediment and 8.76±1.15 µmol CO2 /g wet sediment/day. The qmax values with respect to N and P were not significantly different (P< 0.05). Analysis of bacterial 16S rRNA genes indicated that Alcanivorax spp. were selected in these marine sediments with increasing inorganic nutrient concentration, whereas Cycloclasticus spp. were more prevalent at lower inorganic nutrient concentrations. These data suggest that simple empirical estimates of the proportion of nutrients added relative to crude oil concentrations may not be sufficient to guarantee successful crude oil bioremediation in oxic beach sediments. The data we present also help define the maximum rates and hence timescales required for bioremediation of beach sediments.

Changes in Glutathione, Oxidative Stress and Mitochondrial Membrane Potential in Apoptosis Involving the Anticancer Activity of Cantharidin Isolated from Redheaded Blister Beetles, Epicauta hirticornis

Abstract: The present work describes the anticancer activity of cantharidin isolated from red-headed blister beetles, Epicauta hirticornis and its possible mode of action involving induction of apoptosis, oxidative stress and decrease in glutathione against murine ascites Dalton's lymphoma. The structure of isolated compound was confirmed as cantharidin by X-ray diffraction method. Cantharidin treatment showed potent anticancer activity with an increase in life span (~ 87%) of tumor-bearing mice. Cantharidin treatment induced apoptosis in Dalton's lymphoma cells and also caused an oxidative stress due to generation of reactive oxygen species (ROS) and an increase in lipid peroxidation. The observed canthardin-mediated decrease in glutathione and glutathione related enzymes activities in the tumor cells may weaken the cellular antioxidant system. Moreover, cantharidin treatment also caused a significant decrease in mitochondrial cytochrome c and simultaneous increase in cytosolic cytochrome c which ultimately facilitates activation of caspase 9 and 3 to augment mitochondrial apoptotic pathway causing cancer cell death. Based on the present findings, it may be suggested that cantharidin-mediated anticancer activity could be due to decrease in the protective ability of cancer cells by ROS and subsequent activation of effecter caspases leading to apoptotic cell death.

The influence of counter ion and ligand methyl substitution on the solid-state structures and photophysical properties of mercury(II) complexes with (E)-N-(pyridin-2-ylmethylidene)arylamines

Abstract: Ten neutral monomeric, dimeric and polymeric mercury(II) complexes of compositions HgX2L (3, 8), [HgX2L]2 (1, 2, 4–6 and 7), [Hg(NO3)2L]n (9) and {[Hg(N3)2L]2}n (10) where X = chloride, bromide, iodide, nitrate and azide, and L = (E)-N-(pyridin-2-ylmethylidene)arylamine, are described. Compounds 1–10 were characterized by elemental analyses, and IR and 1H NMR spectroscopic studies. The solution-state photophysical properties of the complexes are highly dependent on the anions as seen in the fluorescence emission features. Single-crystal X-ray crystallography showed that the molecular complexes can aggregate into larger entities depending upon the anion coordinated to the metal centre. Iodide gives discrete monomeric complexes, chloride and bromide generate binuclear complexes formed through Hg–X–Hg bridges, while nitrate and azide lead to 1D coordination polymers. The significant differences in the observed aggregation patterns of the compounds indicate that the anions exert a substantial influence on the formation of the compounds. A further influence upon supramolecular aggregation is the presence of methyl substituents in L3 and L4, which generally enhances the probability of forming supramolecular π⋯π interactions involving the five-membered C2N2Hg chelate rings in their crystal structures.