Speaker
Mrs
Maria Selivanova
(Siberian federal university)
Description
Increase of radioactive contamination in the environment makes the effects of radiation on living organisms very important. Detailed investigations of irradiation of living organisms were conducted using simple assay systems. All biological assay systems are nonspecific and integral. These principal properties account for the field of application of bioassays. The use of microorganisms, of marine luminous bacteria in particular, is currently favoured. The tested parameter is luminescent intensity of bacteria, which can be easily measured instrumentally.
Chronic effect of Tritium, beta-emitting nuclide, on luminous bacteria Photobacterium phosphoreum was studied. Tritium is a widespread radionuclide, its content increases in environment now; evaluation of Tritium effect on living organism is of great importance. Purpose of this work was to study chronic effect of Tritium (0.01–100 MBq/L) on physiological characteristics of bacteria.
It was shown that the presence of Tritium up to 0.1 MBq/L of activities in nutrient media increases bacterial growth and the presence of Tritium of activities exceeded 0.1 MBq/L suppresses it. Sample of exponential stage of growth (6 hours) revealed the absence of distinct effect of Tritium on BL. Sample of stationary stage of growth (22 hours) demonstrated bioluminescence (BL) activation (Irel > 1) up to 8 times. After 95 hours, inhibition of BL intensity (Irel < 1) was observed.
Luminol chemiluminescence method used to evaluate amount of peroxides in Tritium solutions. It was shown, that the presence of Tritium of different activities doesn’t change peroxide content in solutions. Activation can be caused by processes of media ionization, but not peroxide effects. Activation of bacterial growth and BL intensity can be a result of intensification of electron transfer followed by the increase of rates of biochemical processes.
Primary author
Mrs
Maria Selivanova
(Siberian federal university)
Co-author
Dr
Nadezhda Kudryasheva
(Institute of Biophysics SB RAS)
