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Biosorption of Heavy Metals: A Review
-- Ashok Kumar, B S Bisht and V D Joshi
Metallic species mobilized and released into the environment by the technological activities of human tend to persist indefinitely, circulating and eventually accumulating throughout the food chain, thus posing a serious threat to the environment, animals and humans. It is essential to realize that the metal is only removed from solution when it is appropriately immobilized. Apart from slow natural process of metal mineralization, ultimate removal is attained only when the metal becomes concentrated to the point that it can be either returned to the process or resold. The metallic pollutants can be sorbed by biosorbant material. The mechanism of biosorption is complex, mainly ion exchange, chelation, adsorption by physical forces, entrapment in inter and intrafibrilliar capillaries and spaces of the structural polysaccharide network as a result of the concentration gradient and diffusion through cell walls and membranes. Due to the extensive research and significant economic benefits of biosorption, some new biosorbant resources are poised for commercial exploitation. © 2011 IUP. All Rights Reserved.
MicroRNA-Mediated Regulation in Plants
-- B Karpaga Raja Sundari and Modhumita Ghosh Dasgupta
MicroRNAs (miRNAs) are a class of 22 nucleotide non-coding regulatory RNAs which are universal in eukaryotes. They act as negative regulators of gene expression either by targeting mRNAs for cleavage or by translational repression serving as guides in silencing complexes. They participate in regulation of gene expression associated with plant developmental processes like organ morphogenesis and signal transduction pathway. There are more than 872 miRNAs, belonging to 42 families, reported from 71 plant species identified by genetic screening, direct cloning, computational strategy and EST analysis. The paper reviews the present status of miRNA-mediated regulation in plant developmental processes. © 2011 IUP. All Rights Reserved.
Evaluation of Genetic Distances for Cultivar Protection:
A Case Study Comparing Molecular and Morphological
Data in Carnation
-- Tejaswini, Madhavilatha Pagadala, Anuradha Sane,
M V Dhananjaya and Shubha R Rao
The present-day Plant Variety Protection (PVP) is dependent on morphological characters that are used for Distinctness, Uniformity, Stability (DUS) testing. The objective of this study is to asses the utility of Simple Sequence Repeats (SSR) in distinguishing varieties and variants as opposed to clones and species. In this study, we used 16 SSRs for fingerprinting 48 carnation genotypes. As expected in a polyploidy, the number of alleles per locus ranged from single to four. Clustering based on morphological characters could clearly distinguish varieties, variants, species and interspecific hybrids, whereas the clones remained identical. Clustering based on SSR alleles could separate the species and interspecific hybrids with similarity ranging from 0.53 to 0.9. A genetic distance of 0.05 could be noticed between clones.
© 2011 IUP. All Rights Reserved.
Biotyping of Various Strains of Lactobacillus acidophilus
Based on Their Probiotic Properties
-- Bhatia Aruna and Kaur Parvinder
Probiotic bacteria seem to hold great promise as a biotherapeutic agent because of their role in prevention of infectious illness, reinforcing the barrier function of the intestinal flora or strengthening the immune system. Different probiotic species and even different strains exhibit distinctive properties that can markedly affect their survival in foods, fermentation characteristics and other probiotic properties. Acid and bile tolerance of Lactobacillus acidophilus strains make it capable of surviving in the gut. Cholesterol removal property is one of the greatest applications of probiotics exploited. Antimicrobial and antibiotic property explores them further as probiotic. As the bioactivities of probiotics are strain-dependent, biotyping of probiotics is of great importance, especially for the quality control application of approved strains—to avoid health risks and for the description of new species. In the present study, 11 strains of Lactobacillus acidophilus were tested for their acid and bile tolerance, cholesterol removal ability, antimicrobial and antibiotic probiotic properties. The results showed considerable variation among cultures in their growth viability in the presence of acid, bile and removal of cholesterol from the culture medium, antimicrobial and antibiotic properties in vitro. LA 5, strain R showed the best results which indicate that these strains may be promising candidates for use as a dietary adjunct. © 2011 IUP. All Rights Reserved.
Protective Effect of Cyathula prostrata Extract
on Alloxan Induced Diabetes Mellitus in Rats
-- Ajay Kumar
The present study was made to evaluate the antidiabetic effect of Cyathula prostrata extract in alloxan monohydrate induced diabetic rats. Changes in biochemical parameters like aspartate transaminase (AST), alanine transaminase (ALT), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP) in liver, glucose and cholesterol in serum were studied and found to be increased in alloxan induced diabetic rats. This condition was reversed by the oral administration of Methanolic Extract of Cyathula Prostrata (MECP) in Group 3 rats. Our results suggest that the extract possesses a potent medicinal agent for the treatment of diabetes mellitus. © 2011 IUP. All Rights Reserved.
Molecular Dynamics Simulation of Hydrogenase Isoenzyme
Formation Protein HypC
-- Debjani Chakraborty, Uttam Kumar Mondal, Arnab Sen
and Asim K Bothra
Escherichia coli HypC plays an important role in the maturation process of the large subunit of (Ni-Fe) hydrogenase. It is a metal-free enzyme and consists of 90 amino acid residues. To determine the motional properties and mode of action of HypC, molecular dynamics simulation of E. coli HypC in aqueous environment was carried out with GROMACS software. By analyzing the time evolution of Root Mean Square Deviation (RMSD), Radius of Gyration (Rg), Root Mean Square Fluctuation (RMSF), it is clear that the protein is not much flexible. Among the secondary structures, two helices, H1 & H2 and b2 & b4 strands are very much flexible. So they can be used in the protein-protein interaction. A loop L34 (Leu30 to Gln46) is also quite flexible in nature. Principal Component Analysis (PCA) was also performed for a better understanding of the motional properties in reduced dimension. It also suggests that the protein HypC, as a whole, is of rigid nature. © 2011 IUP. All Rights Reserved.
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