DOSE-DEPENDENT EFFECT OF ELECTRON ACCEPTOR AND DONOR ON DISSIMILATORY SULFATE REDUCTION BY BACTERIA DESUFOVIBRIO PIGER VIB-7 OF HUMAN INTESTINE

Abstract

Growth of Desulfovibrio piger Vib-7 bacteria of human intestine under the influence of the electron acceptor and donor in different concentrations and the parameters of dissimilatory sulfate reduction have been studied. An increased intensity of the bacterial growth and production of hydrogen sulfide by the D. piger Vib-7 bacteria was studied under influence of high concentrations of sulfate and lactate (17.4 and 35.6 mM, respectively). The largest quantity of hydrogen sulfide (6.06 mM) under influence of 10.5 mM of SO₄^2- was detected on the 72 hour of cultivation; while the bacteria D. piger Vib-7 used about 58% of sulfate ion. The largest quantity of acetate (21.1 mM) is detected on the 72 the hour of growth during cultivating the D. piger Vib-7 in the medium containing 53.4 mM of lactate. Based on the obtained experimental data surface models of sulfate reduction parameters by D. piger Vib-7 under the influence of electron acceptor and donor different concentrations were constructed. These surface models have provided an opportunity to confirm and establish optimum growing points by the studied bacteria, their sulfate consumption and sulfide production, the lactate consumption and acetate accumulation. The correlation coefficients (r) between parameters of the dissimilatory sulfate reduction by the D. piger Vib-7 were defined. Strong negative and positive correlations between these parameters have been observed.