Cobalt recovery from Metallurgical Wastes of Zinc Industry

Cobalt is a metal of great strategic importance for super alloys which are used in aerospace. Cobalt is also extensively used in the manufacture of cemented carbide tools , magnetic alloys and even in ceramics as a colouring agent. During the hydro-metallurgical processfor extraction of zinc, valuable metals can also be recovered as by-products from the waste materials. Under the `Home Grown Technology Programme ' of TIFAC, a flow sheet has been developed and process optimised for cobalt recovery from metalli rgical wastes from the zinc industry. The work was done jointly by HZL & BARC and has not only resulted in increased yield of cobalt to mop e than 60% but also improved the product quality to achieve 99.8% pure cobalt. This paper briefly outlines the modified process flowsheet consisting of washing, roasting, three stage leaching , oxalate precipitation and solvent extraction. Results of the market survey for cobalt metal and powder carried out as a part of the study are also enclosed

Environment and Waste Management in Metallurgical Industries - Role of databases

Metallurgical industries are responsible for all kinds of pollutants, solid, liquid and gaseous. Due to various technology development efforts towards their abatement, significant quantum of wastes is now being re-cycled and pollutants contained within permissible norms. However, intelligent environment decisions require a comprehensive information base. This paper explains the complexity of setting up databases in environmental and waste management. It also mentions some of the prominent databases available world-wide and in India. Two major initiatives in India on environment databases i.e. ENVIS and TIFACLINE have been described. There is a good potential for India to become a global player in this area

ANTIOXIDANT AND ANTIINFLAMMATORY EFFECTS OF VITEX NEGUNDO ON FREUND'S COMPLETE ADJUVANT INDUCED ARTHRITIS

Objective: Vitex negundo, commonly known as nirgundi†is widely used in traditional as well as in folk medicines to cure many ailments such as fever, rheumatism, gum and skin diseases and liver disorders, etc. The present study evaluated the antioxidant potency of hydroethanolic extract of Vitex negundo leaves (VNE) in Freund's complete adjuvant (FCA) induced arthritis.Methods: Acute oral toxicity test of VNE at various increasing doses and its effect on biochemical markers of hepatotoxicity and renal toxicity along with histopathology were studied. The experimental arthritis was induced by subcutaneous injection of FCA at the right hind paw of male albino rats. Treatment with indomethacin (10 mg/kg body weight) and VNE (200 mg/kg body weight) was given to arthritic rats to study the effects on liver and erythrocytes malondialdehyde (MDA) and antioxidant status. Anti-inflammatory activities were studied by inhibition in paw edema.Results: The results showed that the use of VNE, up to the dose of 5 g/kg body weight was nontoxic. Oral administration of VNE significantly modulated antioxidant status and reduced MDA content. VNE also exhibited anti-inflammatory activity shown by inhibition in paw edema of arthritic rats.Conclusion: Vitex negundo leaves possess potent antioxidant and anti-inflammatory activity by modulating the oxidant/antioxidant in favor of reducing oxidative stress and thereby; the inflammation in FCA induced RA.Â

Completed sequence of aflatoxin pathway gene cluster in Aspergillus parasiticus11The nucleotide sequence data in A. parasiticus reported here are available in the NCBI GenBank database under the accession number AY371490.

AbstractAn 82-kb Aspergillus parasiticus genomic DNA region representing the completed sequence of the well-organized aflatoxin pathway gene cluster has been sequenced and annotated. In addition to the 19 reported and characterized aflatoxin pathway genes and the four sugar utilization genes in this cluster, we report here the identification of six newly identified genes which are putatively involved in aflatoxin formation. The function of these genes, the cluster organization and its significance in gene expression are discussed

ANTI-OXIDATIVE, ANTI-INFLAMMATORY AND ANTI-ATHEROSCLEROTIC EFFECT OF TAURINE ON HYPERCHOLESTEROLEMIA INDUCED ATHEROSCLEROTIC RATS

Objective: The present study evaluates the antioxidant, anti-inflammatory and anti-atherosclerotic potency of taurine (2-amino ethane sulfonic acid) when administered orally to hypercholesterolemia induced atherosclerotic rats.Methods: The experimental atherosclerosis was induced by feeding rats with an atherogenic diet comprising of the normal rat chow supplemented with 4 % cholesterol, 1 % cholic acid and 0.5 % thiouracil (CCT diet) for 20 d. Treatment with atorvastatin (10 mg/kg body weight) and taurine (2 % in drinking water) was given to atherosclerotic rats to study antioxidant enzymes (superoxide dismutase, catalase, glutathione-S-transferase), lipid peroxidation in liver, glutathione reductase and protein carbonyl content, extent of DNA damage using the alkaline comet assay, assaying pro-inflammatory cytokines and quantifying atherosclerotic lesions.Results: Oral supplementation of 2 % taurine to hypercholesterolemic rats modulated antioxidant status and significantly reduced malondialdehyde (MDA) content (P<0.05). The extent of DNA damage was also significantly reduced as observed by a reduction in the comet tail index (P<0.05). Taurine exhibited anti-inflammatory activity by significantly inhibiting TNF-α (tumor necrosis factor) and IL-1α (inter leukine) and also inhibited atherosclerotic lesions by clearing lipid deposits on the intimal surface of the rat aorta.Conclusion: Oral administration of taurine to rats showed antioxidant and anti-inflammatory activity by modulating oxidants in favor of reducing oxidative stress and also showed anti-atherosclerotic activity in hypercholesterolemia-induced atherosclerosis

Alu repeat analysis in the complete human genome: trends and variations with respect to genomic composition

Motivation: Transposon-derived Alu repeats are exclusively associated with primate genomes. They have gained considerable importance in the recent times with evidence of their involvement in various aspects of gene regulation, e.g. alternative splicing, nucleosome positioning, CpG methylation, binding sites for transcription factors and hormone receptors, etc. The objective of this study is to investigate the factors that influence the distribution of Alu repeat elements in the human genome. Such analysis is expected to yield insights into various aspects of gene regulation in primates. Results: Analysis of Alu repeat distribution for the human genome build 32 (released in January 2003) reveals that they occupy nearly one-tenth portion of the sequenced regions. Huge variations in Alu frequencies were seen across the genome with chromosome 19 being the most and chromosome Y being the least Alu dense chromosomes. The highlights of the analysis are as follows: (1) three-fourth of the total genes in the genome are associated with Alus. (2) Alu density is higher in genes as compared with intergenic regions in all the chromosomes except 19 and 22. (3) Alu density in human genome is highly correlated with GC content, gene density and intron density with GC content being major deterministic factor compared with other two. (4) Alu densities were correlated more with gene density than intron density indicating the insertion of Alus in untranslated regions of exons