Gold Nanoparticles with Self-Assembled Cysteine Monolayer Coupled to Nitrate Reductase in Polypyrrole Matrix Enhanced Nitrate Biosensor

We have developed here a novel, highly sensitive and selective nitrate (NO– 3) biosensor by covalent immobilization of nitrate reductase (NaR) in self-assembled monolayer (SAM) of cysteine on gold nanoparticles (GNP)-polypyrrole (PPy) modified platinum electrode. Incorporation of GNP in highly microporous PPy matrix was confirmed by morphological scanning electron microscope (SEM) images. The electrochemical behavior of the NaR modified electrode exhibited the characteristic reversible redox peaks at the potential, –0.76 and –0.62 V versus Ag/AgCl. Further, the GNP-PPy nanocomposite enhanced the current response by 2-fold perhaps by enhancing the immobilization of NaR and also direct electron transfer between the deeply buried active site and the electrode surface. The common biological interferences like ascorbic acid, uric acid were not interfering with the NO– 3 measurement at low concentration levels. This biosensor showed a wide linear range of response over the concentration of NO– 3 from 1 μM to 1 mM, with higher sensitivity of 84.5 nA μM–1 and a detection limit of 0.5 μM. Moreover, the NO– 3 level present in the nitrate-rich beetroot juice and the NO– 3 release from the lipopolysaccharide treated human breast cancer cells were estimated

Genetic diversity analysis in the section Caulorrhizae (genus Arachis) using microsatellite markers

Diversity in 26 microsatellite loci from section Caulorrhizae germplasm was evaluated by using 33 accessions of A. pintoi Krapov. & W.C. Gregory and ten accessions of Arachis repens Handro. Twenty loci proved to be polymorphic and a total of 196 alleles were detected with an average of 9.8 alleles per locus. The variability found in those loci was greater than the variability found using morphological characters, seed storage proteins and RAPD markers previously used in this germplasm. The high potential of these markers to detect species-specific alleles and discriminate among accessions was demonstrated. The set of microsatellite primer pairs developed by our group for A. pintoi are useful molecular tools for evaluating Section Caulorrhizae germplasm, as well as that of species belonging to other Arachis sections

Chickpea

The narrow genetic base of cultivated chickpea warrants systematic collection, documentation and evaluation of chickpea germplasm and particularly wild Cicer species for effective and efficient use in chickpea breeding programmes. Limiting factors to crop production, possible solutions and ways to overcome them, importance of wild relatives and barriers to alien gene introgression and strategies to overcome them and traits for base broadening have been discussed. It has been clearly demonstrated that resistance to major biotic and abiotic stresses can be successfully introgressed from the primary gene pool comprising progenitor species. However, many desirable traits including high degree of resistance to multiple stresses that are present in the species belonging to secondary and tertiary gene pools can also be introgressed by using special techniques to overcome pre- and post-fertilization barriers. Besides resistance to various biotic and abiotic stresses, the yield QTLs have also been introgressed from wild Cicer species to cultivated varieties. Status and importance of molecular markers, genome mapping and genomic tools for chickpea improvement are elaborated. Because of major genes for various biotic and abiotic stresses, the transfer of agronomically important traits into elite cultivars has been made easy and practical through marker-assisted selection and marker-assisted backcross. The usefulness of molecular markers such as SSR and SNP for the construction of high-density genetic maps of chickpea and for the identification of genes/QTLs for stress resistance, quality and yield contributing traits has also been discussed

Cerium oxide nanoparticles promote neurogenesis and abrogate hypoxia-induced memory impairment through AMPK–PKC–CBP signaling cascade

Aditya Arya,1 Anamika Gangwar,1 Sushil Kumar Singh,2 Manas Roy,3,4 Mainak Das,3 Niroj Kumar Sethy,1 Kalpana Bhargava1 1Peptide and Proteomics Division, Defense Institute of Physiology and Allied Sciences, 2Functional Materials Division, Solid State Physics Laboratory, Defense Research and Development Organization, Timarpur, Delhi, 3Biological Science and Bioengineering, Indian Institute of Technology, Kanpur, 4Department of Chemistry, Indian Institute of Engineering Science and Technology, Howrah, India Abstract: Structural and functional integrity of the brain is adversely affected by reduced oxygen saturation, especially during chronic hypoxia exposure and often encountered by altitude travelers or dwellers. Hypoxia-induced generation of reactive nitrogen and oxygen species reportedly affects the cortex and hippocampus regions of the brain, promoting memory impairment and cognitive dysfunction. Cerium oxide nanoparticles (CNPs), also known as nanoceria, switch between +3 and +4 oxidation states and reportedly scavenge superoxide anions, hydrogen peroxide, and peroxynitrite in vivo. In the present study, we evaluated the neuroprotective as well as the cognition-enhancing activities of nanoceria during hypobaric hypoxia. Using polyethylene glycol-coated 3 nm nanoceria (PEG-CNPs), we have demonstrated efficient localization of PEG-CNPs in rodent brain. This resulted in significant reduction of oxidative stress and associated damage during hypoxia exposure. Morris water maze-based memory function tests revealed that PEG-CNPs ameliorated hypoxia-induced memory impairment. Using microscopic, flow cytometric, and histological studies, we also provide evidences that PEG-CNPs augmented hippocampus neuronal survival and promoted neurogenesis. Molecular studies revealed that PEG-CNPs promoted neurogenesis through the 5'-adenine monophosphate-activated protein kinase–protein kinase C–cyclic adenosine monophosphate response element-binding protein binding (AMPK-PKC-CBP) protein pathway. Our present study results suggest that nanoceria can be translated as promising therapeutic molecules for neurodegenerative diseases. Keywords: cerium oxide nanoparticles, oxidative stress, memory, hypoxia, neuroprotectio

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Not AvailableAccelerated soil erosion degrades soil quality and undermines ecosystem functions and services. It is important to assess the severity of erosion, demarcate tolerable limits for sustainable crop production, conservation planning for soil resources, and identify the alternative land uses. Irrespective of soil type, climate and vegetation cover, the tolerable level of soil erosion in India has traditionally been taken as 11.2 Mg ha−1 year−1. However, this is an excessive rate for most agro-ecosystems and land uses; hence, this study aims to establish credible soil loss tolerance (‘T’ values) for some soils of western India on the basis of critical soil parameters (i.e., bulk density, infiltration rate, total organic carbon and soil reaction). The condition of a soil or ‘soil state’ (S) is defined through a quantitative model involving different soil functions. The ‘T’ values for some soils of western India ranged between 2.5 and 12.5 Mg ha−1 year−1 compared to default ‘T’ value of 11.2 Mg ha−1 year−1. About 50% of the land area has ‘T’ value >10 Mg ha−1 year−1, and the remaining 50% has <7.5 Mg ha−1 year−1, of which 13.02 M ha is having only ‘T’ value of 2.5 Mg ha−1 year−1. Using the revised ‘T’ values for soil mapping units will help in planning of appropriate conservation measures for effective erosion control, sustainable crop production and improved watershed management in the Rajasthan State of western IndiaNot Availabl

Recent trends in electrochemical biosensors of superoxide dismutases

Superoxide dismutases (SODs), a family of ubiquitous enzymes, provide essential protection to biological systems against uncontrolled reactions with oxygen- and nitrogen- based radical species. We review first the role of SODs in oxidative stress and the other biological functions such as peroxidase, nitrite oxidase, thiol oxidase activities etc., implicating its role in neurodegenerative, cardiovascular diseases, and ageing. Also, this review focuses on the development of electrochemical label-free immunosensor for SOD1 and the recent advances in biosensing assay methods based on their catalytic and biological functions with various substrates including reactive oxygen species (superoxide anion radical, hydrogen peroxide), nitric oxide metabolites (nitrite, nitrate) and thiols using thiol oxidase activity. Furthermore, we emphasize the progress made in improving the detection performance through incorporation of the SOD into conducting polymers and nanocomposite matrices. In addition, we address the potential opportunities, challenges, advances in electrochemical-sensing platforms and development of portable analyzer for point-of-care applications

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Not AvailableA total of 48 surface (0-15 cm) and sub-surface (15-30 cm) samples were collected representing six different land use systems under table landscape of Chambal region. Soil properties were evaluated under six different land uses in Chambal region. Soils under perennial vegetation recorded highest organic carbon content (0.72- 0.85%), which was 2.0 to 2.4 times higher than the soils under cultivated rainfed cropped fields (0.36%). The soils under perennial vegetations and cultivated areas had higher clay content (37.80-42.0%) whereas, ravine lands recorded the lowest clay content (20.2-22.85%). The microaggregate (0.002- 0.2mm) distribution was higher under cultivated (irrigated cropping) land and the lowest was recorded in grassland. However, Grass land recorded greater proportion of larger aggregate (>5mm) in both surface and sub-surface soils compared to other land uses and lower per cent was recorded under irrigated cropping. The soils under continuous cultivation recorded higher micro-aggregate proportion than other land uses. It is evident from the study that soils under grasslands and perennial vegetation registered higher macroaggregate. The highest mean weight diameter (MWD) was recorded under grass land followed by irrigated and rainfed crops under both the soil depths. The cultivated fields recorded higher proportion of microaggregates, due to structural breakdown under these land use system. Therefore, proper soil conservation measures along with additions of organic manures help in reducing soil erosion and improvement of soil properties.Not Availabl