Surface characterization and metal ion adsorption properties of Spirulina sp. and Spirulina maxima were verified by various instrumental techniques. FTIR spectroscopy and potentiometric titration were used for qualitative and quantitative determination of metal ion-binding groups. Comparative FTIR spectra of natural and Cu(II)-treated biomass proved involvement of both phosphoryl and sulfone gr...

Background: The removal of toxic metals from sewage and wastewaters is one of the most important concerns in the twenty first century. The removal of poisonous Cr(VI) from aqueous solution by different low-cost available nanoporous adsorbents was investigated in the present study.  Methods: Fumed silica, bentonite (BN), hydrotalcite (HT), MCM-41, Na-Y, mordenite (MOR) and SAPO-34 were ...

Voltage-gated Na⁺-channels are transmembrane proteins that are responsible for the fast depolarizing phase of the action potential in nerve and muscular cells. Selective permeability of Na⁺ over Ca²⁺ or K⁺ ions is essential for the biological function of Na⁺-channels. After the emergence of the first high-resolution structure of a Na⁺-channel, an anionic coordination site was proposed to confer...

Positively charged lipid bilayer systems are a promising class of nonviral vectors for safe and efficient gene and drug delivery. Detailed understanding of these systems is therefore not only of fundamental but also of practical biomedical interest. Here, we study bilayers comprising a binary mixture of cationic dimyristoyltrimethylammoniumpropane (DMTAP) and zwitterionic (neutral) dimyristoylp...

In the duck red blood cell, Na-K-2Cl cotransport exhibits two modes of ion movement: net cotransport and obligate cation exchange. In high-K cells, the predominant exchange is K/K (or K/Rb). In high-Na cells, it becomes Na/Na (or Na/Li). Both represent partial reactions in which a fully loaded carrier releases part of its cargo, rebinds fresh ions, and returns back across the membrane fully loa...

The kinetics of Na+ activation of brush border sucrase (sucrose D-glucosidase E.C. 3.2.1.48) has been studied in mice intestine. At pH 5.0, 50 mM Na+ ions stimulated sucrase activity by 84%. At pH 7.2, enzyme stimulation was reduced to 16%, whereas, atpH 8.5, 10-100 mMNa+ ions produced 18-45% inhibition of enzyme activity. Kinetic studies revealed that at pH 5.0, the enzyme activation by Na+ io...

2/3 of the reservoir surface area was approximately covered with dense populations of Myriophyllum, Ceratophyllum and Potamogeton species. The headwaters of the reservoir were considered as hard water and had both carbonatic and non-carbonatic hardness. When they were exposed to lentic condition of the reservoir and its intensive photosynthetic activities of macrophyte communities, the bicarbon...

Based on the following observations we propose that the cytoplasmic loop between trans-membrane segments M6 and M7 (L6/7) of the a subunit of Na,KATPase acts as an entrance port for Na and K ions. 1) In defined conditions chymotrypsin specifically cleaves L6/7 in the M5/M6 fragment of 19-kDa membranes, produced by extensive proteolysis of Na,K-ATPase, and in parallel inactivates Rb occlusion. 2...

matricaria chamomilla is a medicinal plant that is widely cultivated in salt affected soils. this investigation was undertaken to study the effect of nacl concentration on germination, and the physiological, biochemical and growth characteristics of chamomile. seed germination and growth were studied at five nacl concentration levels (0, 40, 80, 120 and 190 mm nacl concentration). increasing th...