On the electrodeposition of reactive metals from ionic liquids

In this paper we show that ionic liquids can be used for the electrodeposition of highly reactive elements, which can not be obtained from aqueous solutions, such as aluminium, magnesium and lithium as well as of refractory metals such as tantalum and titanium. The development of ionic liquids, especially air and water stable ones, has opened the door for the electrodeposition of reactive elements which in the past were only accessible using high temperature molten salts or, in part, organic solvents. Due to their high stability, ionic liquids can be regarded as the missing link to high temperature molten salts. Currently, ionic liquids can not yet replace molten salts in the electrowinning of reactive and refractory metals. Nevertheless, they can be employed efficiently for the coating of other metals with thin layers of tantalum, aluminum and presumably many other ones at reasonable temperatures. From a practical point of view, molten salts are hardly suited for the coating of sensitive materials like NiTi shape memory alloy with other metals since the electrolysis process is performed usually at temperatures above 400 C. With ionic liquids a technical electroplating process might be performed at moderate or even at room temperature

Investigations on the glucosinolates of lepidium sativum growing in Egypt and their biological activity

Fractionation of the glucosinolate contents of both the seeds and fresh herb of Lepidium sativum growing in Egypt were carried out. The study of the glucosinolate contents of L. sativum seeds revealed the isolation and identification of glucotropaeolin and 2- Phenyl ethyl glucosinolate while the study of glucosinolate contents of the fresh herb revealed the presence of 2- ethyl butyl glucosinolate, methyl glucosinolate, butyl glucosinolate and glucotropaeolin. The identification of the isolated glucosinolates were substantiated through using different chemical methods [enzymatic hydrolysis] and spectroscopic determinations [UV, MS and GC-MS for the corresponding isothiocyanates]. Acute toxicity studies of pet ether and alcoholic extracts of aerial parts of the plant showed that the alcoholic extract is more safe than that of pet ether extract and both extracts have a hepatoprotective activity on liver at the same concentration [50 micro g/ml]. The different extracts of the seeds and herbs of Lepidium sativum showed a potent effect against the White fly [Bemisia tabaci]. The total glucosinolate and in particular glucotropaeolin showed significant activity against the pest, which gave a highest mortality percentage on the adult stage

Production and characterization of milk-clotting enzymes by Bacillus circulans NRC-3

The production of Milk-clotting enzyme was investigated using seven bacterial isolates. Bacillus circulans NRC-3 proved to be the most potent and produced a highly active milk-clotting enzyme with negligible proteolytic activity on wheat bran medium as a food byproduct. The milk- clotting enzyme activity was optimal at 50°C and CaC12 of final concentration of 0.3 mM. The enzyme was highly stable at elevated temperatures [70°C] and retained more than 60% of the original activity by heating for 5min.at 70°C. Partial purification of the enzyme was achieved by fractional precipitation with acetone or ethanol. The 40% acetone fraction was the most promising and possessed rennin properties with no proteolytic activity. It reached about 4.3-fold that of the culture filtrate. The partial purified B.circulans NRC-3 milk-coltting enzyme was applied on three buffalo fresh milk specimens, i.e. full- cream, half- cream and skimmed fresh. The enzyme exhibited the maximum relative activity [100%] with both half- cream and skimmed fresh milk specimens and dropped to 67.1% with the full- cream specimen