Isotopic Resonance Hypothesis: Experimental Verification by Escherichia coli Growth Measurements

Isotopic composition of reactants affects the rates of chemical and biochemical reactions. As a rule, enrichment of heavy stable isotopes leads to progressively slower reactions. But the recent isotopic resonance hypothesis suggests that the dependence of the reaction rate upon the enrichment degree is not monotonous. Instead, at some “resonance” isotopic compositions, the kinetics increases, while at “off-resonance” compositions the same reactions progress slower. To test the predictions of this hypothesis for the elements C, H, N and O, we designed a precise (standard error ±0.05%) experiment that measures the parameters of bacterial growth in minimal media with varying isotopic composition. A number of predicted resonance conditions were tested, with significant enhancements in kinetics discovered at these conditions. The combined statistics extremely strongly supports the validity of the isotopic resonance phenomenon (p ≪ 10(−15)). This phenomenon has numerous implications for the origin of life studies and astrobiology, and possible applications in agriculture, biotechnology, medicine, chemistry and other areas

Production of sulfur from gypsum as an industrial by-product.

[en] Biological sulfate reduction was investigated at the bench and pilot scales in order to determine optimum culture conditions. Efficient strains of sulfate-reducing bacteria (SRB) were selected by classical microbiological methods and by mutagenesis. Improvement factors, including stripping, scale-up, sulfate,and organic substrate concentrations, have been studied in batch bioreactors. Two types of pilot-scale bioreactors have been adopted, the first being completely mixed with free cells and the second having two stages with immobilized cells on a fixed bed. An overall bioconversion capacity of 11 kg/m(3) .d of gypsum and 1.2 kg/m(3) .d of dissolved organic carbon has been achieved in the two-stage bioreactor.info:eu-repo/semantics/publishe