Nonlinear changes in the activity of the oxygen-dependent demethylase system in Rhodococcus erythropolis cells in the presence of low and very low doses of formaldehyde

The effect of exogenous, highly diluted formaldehyde on the rate of demethylation/re-methylation of veratric acid by the bacteria Rhodococcus erythropolis was studied using electrophoretic and microscopic techniques. The activity of 4-O-demethylase, responsible for accumulation of vanillic acid, and the levels of veratric and vanillic acids were determined using capillary electrophoresis. Formaldehyde was serially diluted at 1:100 ratios, and the total number of iterations was 20. After incubation of the successive dilutions of formaldehyde with the bacteria, demethylase activity oscillated in a sinusoidal manner. It was established using capillary electrophoresis that methylation of vanillic acid to veratric acid occurred at a double rate, as shown by the doubled fluctuation in the concentration of veratrate. There were also changes in the NADH oxidase activity, which is associated with methylation processes. Microscopic observations revealed the presence of numerous enlarged vacuoles in bacterial cells during the accumulation of large amounts of vanillic acid, and their disappearance together with a decrease in 4-O-demethylase activity. The presented results give evidence for the ability of living cells to detect the presence of submolecular concentrations of biological effectors in their environment and provide a basis for a scientific explanation of the law of hormesis and the therapeutic effect of homeopathic dilutions

Non-linearity of Plant Resistance to Pathogens Induced by N-methylated Compounds

The N-methylated resistance inducers act within two concentration ranges characterized by suppression of infection rates. Between these active ranges there is always an inactive range (5-7 decimal dilutions) characterized in general by a high rate of infection. This unique phenomenon is called the double immune response, which means a non-linear effect. If the time interval between pre-treatment and inoculation increases the active concentration values for the double immune response shift towards original higher dose values because of the continuous metabolism of methylated inducer in the host plant. The inactive range between the two active dose values remains the same. The multiple pre-treatment of plants with the inducer gives contrasting results: the active dose ranges shifted towards the original lower values. It seems that the two active concentrations of the inducer are always the same. Methylated inducers are potential formaldehyde (HCHO) generators. HCHO generates a time- and dose-dependent immunostimulating activity. HCHO (mainly in bound form) and H2O2 can interact and the singlet oxygen and excited HCHO can be formed. The singlet oxygen may participate in the oxidation of water molecules and in biological systems previously unknown oxidants including dihydrogen trioxide and ozone, can be generated. It seems that these reactive molecules-from HCHO to O3- form the biochemical basis of the double immune response of plants to pathogens

Effect of Low and Very Low Doses of Simple Phenolics on Plant Peroxidase Activity

Changes in the activity of horseradish peroxidase resulting from an addition of ethanol water dilutions of 19 phenolic compounds were observed. For each compound, the enzyme activity was plotted against the degree of dilution expressed as n = –log100 (mol/L) in the range 0 ≤ n ≥ 20. All the curves showed sinusoidal activity, more or less regular, with two to four peaks on average. Each analyzed compound had a characteristic sinusoidal shape, which was constant for samples of peroxidase from various commercial firms. This was clearly visible after function fitting to experimental results based on the Marquadt–Levenberg algorithm using the least-squares method. Among the 19 phenolics, the highest amplitudes were observed for phenol and iso- and vanillate acids and aldehydes. The specific character of each of the analyzed curves offers a possibility of choosing proper dilutions of phenolic compound for activating or inhibiting of peroxidase activity