No abstract

In the preceding paper (Mahadevan, Seshadri Sastry & Ganguly, 1963) experiments with living animals have shown that vitamin A esters are hydrolysed and resynthesized during absorption. In this paper, where experiments conducted in vitro with everted intestinal sacs of rats are described, further evidence is produced to show that prior hydrolysis of vitamin A esters is essential for the

No abstract

Over the past century, unrestricted mining, extensive industrialization, modern agricultural practices and faulty waste disposal methods have resulted in the release of unprecedented levels of toxic heavy metals like Cd, Hg, Ag, Sn, Pb, Cu, Co, Mn, Zn, etc into the environment. Many metals are essential for microbial growth in less concentration, yet are toxic in higher concentrations. Biosorption is an attractive alternative approach which involves the binding or adsorption of heavy metals to living or dead cells. Many microbes have the ability to selectively accumulate metals.The present study is intended to analyze the uptake systems of Bacillus and E. coli against different conc. of heavy metals like Zn, Cu, Cd, and Hg in their salt form incorporated into nutrient broth medium observed over a regular interval of time. Analysis was based on how much of the metal from the original conc. Used was left behind in the media after the rest being up taken by the organism. This was done using AAS which was indirectly the representation of percent uptake of heavy metal by the respective organism.The study showed that Gram -ve organisms like E. coli exhibited more resistance to metals like Zn, Cu and Hg in relative comparison with Gram +ve organisms like Bacillus. Bacillus sps was less sensitive to effect of Cd than in E. coli.