Juanita C. Mamaril | Estela T. Paner | Vilma T. Capuno | Lorele C. Trinidad
Five strains of Rhizobium sp isolated from the roots of Leucaena leu.cocephala (ipil-ipil) and one from Glycine max (soybean) weTe obseTVed to synthesize pTodigious amount of extracellular mucilaginous polysaccharides. These strains were tested to find out how effective they were in reducing the concentrations of heavy toxic metals, Hg, Cd and Pb from liquid media. The use of rhizobial polysaccharides as sequestering agents for heavy metals will provide a new technology for environmental management. The rhizobial strains were grown in yeast extract mannitol broth (YEMB) containing the heavy metal at two concentrations, 500 ug and 1,000 ug/L. These concentrations are 10 to 100 times higher than the WHO limits for these toxic metals. Concentrations of 10, 20, 30 and 100 ppm of the metals were also studied. The period of incubation ranged from 4 to 10 days, after which the cell culture was centrifuged and the supernatant analyzed for its heavy metal content by isotachophoretic methods of analysis. Results show a drastic reduction of heavy metal concentration in the supernatant to below WHO limits of 10 ug/L and 100 ug/L Pb. Transmission electron micr
ISSN 2719-1990 (Print)
Philippine E-Journals
