Isolation and purification of lipase from Bacillus subtilis in oil mill.

In this study, the lipolytic Bacillus subtilis was isolated from the oil mill waste by Enrichment technique.The isolated colonies were screened on Tributyrin agar medium, colonies which produce the maximum clear zone of the particular organisms was used for further optimization studies. Among the 3 isolates Bacillus subtilis a single isolate was the subjected to solid state fermentation medium and the enzyme characteristics were studied with respect to pH, temperature and incubation period.The production and lipase activity were found maximum 0.45U/mL at pH, 0.45U/mL at temperature 37°C and 0.41U/mL at incubation period 48 hours. The lipase purification steps involved, 60% ammonium sulphate saturation and ion exchange chromatography with DEAE cellulose. To apparent homogeneity as evident by a single band of 62.2kDa on sodium dodecyl sulphate polyacrylamide gel electrophoresis. From the study it was concluded that the commercially important enzyme can be produced by submerged fermentation techniques using frequently available edible oil sources it can be used for the biodegradation of oil effluents.

Radioprotective effect of whole-body hyperthermia on mice exposed to lethal doses of total-body gamma irradiation.

The whole-body hyperthermia (40 degrees C, 1 hr) 20-48 hr prior to total-body irradiation (TBI) with 9 Gy gamma rays gave 80% protection as assessed by survival of the animals. However this was reduced to 50% when mice were irradiated 7 or 15 days after hyperthermia. The local hyperthermia (42 degrees C, 1 hr) given prior to irradiation, on the other hand, did not show any protective effect. The whole-body or local hyperthermia given after TBI had no protective effect on survival of animals.

A sensitive assay for Staphylococcus aureus nucleases.

A sensitive assay for staphylococcal nuclease involving incubation of the enzyme sample with heat-denatured [3H]thymidine labelled DNA from E. coli, precipitation with trichloroacetic acid and measurement of the radioactivity of acid-soluble nucleotides released has been developed. The assay is sensitive enough to be used for comparing the levels of nucleases elaborated by different strains of S. aureus as well as for determining the extent of contamination of S. aureus in food and water samples even at levels at which the conventional spectrophotometric and toluidine blue-DNA methods are totally inadequate.