CHANGE IN SURFACE PROPERTIES OF LACTOBACILLUS REUTERI DSM 17938 AND SACCHAROMYCES BOULARDII UNDER METHYLPREDNISOLON TREATMENT
BOYANA ANGELOVA1, VIRJINIA DOLTCHINKOVA1*
1 Department of Biophysics and Radiobiology, Faculty of Biology, Sofia University “St. Kliment Ohridski”, Bulgaria
*Corresponding author: dolchinkova@biofac.uni-sofia.bg
Keywords: Lactobacillus reuteri, Saccharomyces boulardii, Zeta potential, Dynamic Light Scattering, laser Doppler velocimetry, methylprednisolon
Abstract: We undertake this study in the aim to give new insight about the surface properties of microorganism under Medrol® (methylprednisolon) treatment. The several properties of the cell surface of Lactobacillus reuteri was determined by a variety of physico-chemical methods. Saccharomyces boulardii yeasts as another control of probiotic to Medrol interaction with the cell membrane was used. The study was carried out by microelectrophoresis, dynamic light scattering and laser Doppler velocimetry. We discuss the importance of properly selecting the suspending medium of zeta potential of bacterial cells are to be determined.
Medrol altered the surface electrical charges and size of Lactobacillus reuteri DSM 17938 (L. reuteri Protectis®) membrane at doses of 0.5 μg Medrol/mL and at 0.3 – 0.8 mg Medrol/mL. We suggest that the negative charges on the surface of L. reuteri were increased by the alteration in specific conductivity. Medrol could penetrate the bacterial membrane and changed the permittivity of the L. reuteri membrane surface and changed the particle volume.
There was an enhancement of zeta potential (ζ) of S. boulardii yeasts and volume under the action of 0.2 and 0.4 μg Medrol/mL and significant reduction of ζ and volume upon 1 μg Medrol/mL or 5 μg Medrol/mL in distilled water media.
It is pointed out that the above methods form a unique set of techniques for studying microbial cell surfaces, in the sense that the results of the various methods allow an interpretation of the physicochemical properties of the cells in terms of their chemical composition.