Liposome formation of egg lecithin and its interaction with iodine

The sonicated dispersion of egg lecithin (phosphatidylcholine) in water forms 1:1 molecular complex with iodine, when its concentration is above 1.6 X 10(-5) M. The thermodynamic and spectrophotometric properties of this complex have been determined. The thermodynamic values are: K (25 degrees C) = 1.6 X 10(3) 1 X mol-1, delta G degrees = -18.4 KJ X mol-1, delta H degrees = -27.4 KJ X mol-1 and delta S degrees = -30.0 J X mol-1 X deg-1. The complex shows two absorption bands: one at 293 nm, which is the charge transfer band and the other at 370 nm, which is the blue shifted visible iodine band at 460 nm in water.     

Microbial electron uptake in microbial electrosynthesis: a mini-review

Journal of Industrial Microbiology & Biotechnology - Microbial electron uptake (EU) is the biological capacity of microbes to accept electrons from electroconductive solid materials. EU has...     

Coastal sand mining of heavy mineral sands: Contestations,resistance, and ecological distribution conflicts at HMS extraction frontiers across the world

Coastal sand mining for metals involves extraction of heavy mineral sands (HMS), which are sedimentary deposits of dense minerals that accumulate in coastal environments. HMS are localized concentrations of ores such as ilmenite, rutile, leucoxene, and iron, which are sources of metals such as titanium, zircon, iron, sillimanite/kyanite, staurolite, monazite, and garnet. The applications of these metals range from everyday products such as ceramics, paint, and pigments, as well as technologically advanced applications in the airline, shipbuilding, medicine, and defense industries. HMS extraction implies strip mining of coastal areas, which are often unique biodiversity ecosystems, or fragile ecosystems built up on sandy soils or dunes. The loss of such spaces has impacts such as loss of biodiversity and habitats, salt-water intrusion into agricultural lands and increased exposure to sea level rise. As a result of the serious ecological and socioeconomic transformations at such extraction frontiers, these operations cause resistance movements across the world. This article identifies and documents 24 cases of resistance against such operations. It presents the first comprehensive database and analysis of HMS related ecological distribution conflicts.     

Comparative Toxicities of Salts on Microbial Processes in Soil

Soil salinization is a growing threat to global agriculture and carbon sequestration, but to date it remains unclear how microbial processes will respond. We studied the acute response to salt exposure of a range of anabolic and catabolic microbial processes, including bacterial (leucine incorporation) and fungal (acetate incorporation into ergosterol) growth rates, respiration, and gross N mineralization and nitrification rates. To distinguish effects of specific ions from those of overall ionic strength, we compared the addition of four salts frequently associated with soil salinization (NaCl, KCl, Na₂SO₄, and K₂SO₄) to a nonsaline soil. To compare the tolerance of different microbial processes to salt and to interrelate the toxicity of different salts, concentration-response relationships were established. Growth-based measurements revealed that fungi were more resistant to salt exposure than bacteria. Effects by salt on C and N mineralization were indistinguishable, and in contrast to previous studies, nitrification was not found to be more sensitive to salt exposure than other microbial processes. The ion-specific toxicity of certain salts could be observed only for respiration, which was less inhibited by salts containing SO₄²⁻ than Cl⁻ salts, in contrast to the microbial growth assessments. This suggested that the inhibition of microbial growth was explained solely by total ionic strength, while ion-specific toxicity also should be considered for effects on microbial decomposition. This difference resulted in an apparent reduction of microbial growth efficiency in response to exposure to SO₄²⁻ salts but not to Cl⁻ salts; no evidence was found to distinguish K⁺ and Na⁺ salts.     

A Combined Spectroscopic and Theoretical Analysis of Plasmonic Silver Nanoparticle Sensor Towards Detailed Microscopic Understanding of Heavy Metal Detection

Plasmonic nanoparticles are of great importance owing to their highly responsive ‘localized surface plasmon resonance’ (LSPR) behaviour to self-agglomeration/aggregation leading to the development of various nanosensors. Herein, we demonstrated the definite self-assembly of citrate functionalized silver nanoparticles (AgNPs) into a one-dimensional linear chain in presence of charged lead ions (Pb²⁺), one of the most toxic heavy metal pollutants. We have explored detail mechanism using a variety of spectroscopic tools and electron microscopy. The self-aggregation of AgNPs leads to the generation of new LSPR modes due to coupling of nearby existing modes. The conclusion of our experimental findings is duly supported by our developed numerical modelling based on the quasi-static approximation that the generated new LSPR modes are solely due to formation of chain-like aggregation of AgNPs. We have also monitored the LSPR spectra in the presence of other metal ions; however, only Pb²⁺ found to give such unique self-assembled geometry may due to its high interaction affinity with citrate. These findings play a key role for citrate functionalised AgNPs to be used as a low cost highly selective and sensitive lead ion sensor for potential application in industrial lead pollution monitoring. We have further varied several sensor parameters such as AgNPs size, concentration, and the allowed reaction time for it to be practically implemented as an efficient lead sensor meeting the Environmental Protection Agency recommendations.

Graphical abstract

The possible sensing mechanism of citrate-functionalized silver nanoparticles towards Pb2?+?followed by unique chain-like aggregation for potential atmospheric and industrial lead pollution monitoring.

     

Venom-Derived Bioactive Compounds as Potential Anticancer Agents: A Review

International Journal of Peptide Research and Therapeutics - Biologically active compounds with potential anticancer activity have been isolated from various animal sources. Recent research is...     

Twin‐based heritability of actimetry traits

There is a critical need for phenotypes with substantial heritability that can be used as endophenotypes in behavioral genetic studies. Activity monitoring, called actimetry, has potential as a means of assessing sleep and circadian rhythm traits that could serve as endophenotypes relevant to a range of psychopathologies. This study examined a range of actimetry traits for heritability using a classic twin design. The sample consisted of 195 subjects from 45 monozygotic (MZ) and 50 dizygotic (DZ) twin pairs aged 16‐40 years. Subjects wore both a research‐grade actimeter (GENEActiv) and a consumer‐oriented device (FitBit) for 2 weeks. Sleep and circadian traits were extracted from GENEActiv data using PennZzz and ChronoSapiens software programs. Sleep statistics for a limited number of FitBit‐collected traits were generated by its accompanying mobile app. Broad sense heritability was computed on a set of 33 MZ and 38 DZ twin pairs with complete data using both OpenMX and SOLAR software. These analyses yielded a large number of actimetry‐derived traits, 20 of which showed high heritability (h² > 0.6), seven of which remain significant after Bonferroni correction. These results indicate that actimetry enables assessing a range of phenotypes with substantial heritability that may be useful as endophenotypes for genetic studies.     

Iron-Induced Apoptotic Cell Death and Autophagy Dysfunction in Human Neuroblastoma Cell Line SH-SY5Y

Biological Trace Element Research - Iron accumulation plays a major role in neuronal cell death which has severe effects on mental health like neurodegenerative disorders. The present work aims to...