The non-contact effect of substances containing benzene rings and heterocycles on biological systems

It was found that some substances containing benzolic rings and heterocyclic structures have a noncontact effect on biosystems. Some results of experiments dealing with the noncontact effect on enzyme molecules, cells, and uni- and multicellular organisms are presented. Factors influencing the efficiency of the noncontact effect were revealed.     

The effect of fire on soil humic substances

Summary High temperature effects on soil humic substances were investigated both in natural and laboratory conditions. Differential Thermal Analysis and pyrolysis show that only temperatures above 250°C produce changes in the humic acid fraction. The mean change is a loss of weight due to decarboxylation. Isotachophoretic studies also show that temperatures higher than 250°C produce alteration in the separation pattern of the different subfractions due to changes in the ‘core’ or/and in the amount of carboxyl and hydroxyl groups. Isotachophoregrams done on soil samples extracted from an area before and after fire show no differences. This result is taken as an indication that there was no direct effect of the temperature on the soil humic substances.     

The effect of humic substances on the respiration and growth of micro-organisms

Summary The main effects exerted by humic substances on plant and microbial metabolism are outlined. The effect of various humic fractions obtained from peat are examined using a yeast,Candida utilis as a test organism. Humic fractions exerted no effect on respiration or growth of the micro-organism. Various postulates are put forward to account for this no effect response.     

Kinetics of formation of humic substances in activated sludge systems and their effect on flocculation

Humic substances were isolated during batch aeration studies with activated sludge and a complex waste source, by using concentration and separation techniques that employ reverse osmosis, ultrafitration, and gel permeation chromatography. The study suggests that the formation of high molecular weight humic substances may occur after the removal of the readily available carbon source. The amount of refractory material finally present in the solution will depend on its adsorptive properties toward bacterial cells. The adsorptive characteristics may be determined by the magnitude of the carbohydrate fraction present in the humic substances. If the carbohydrate content decreases, adsorption onto the cells may decrease resulting in an impairment of both the floe formation and settleability of the sludge floes. Decreased adsorption will result in a higher total organic carbon content and an increase in color bearing materials in the effluent.     

The effect of pharmacologic substances on intraspecies aggression]

It is found, that aggression which occures in rats under inevitable painful stimulation is coursed as excessive excitation of the rats. This aggression may be used for revealing the sedative effect of drugs. The method of fighting for the stool which is caused by motivated fighting for the territory was worked out. This motivated aggression may be used for revealing the tranquillizing effect of drugs. Using these methods it is found that stelasine, haloperidol, amitriptyline, imipramine, chlordiazepoxide, diazepam and benactyzine in small doses have a tranquillizing effect, while pentobarbital and chlorpromazine have primarily a sedative effect.     

Evidence for the antimutagenicity and the mutagenicity of selenium

Evidence is summarized for the antimutagenicity as well as the mutagenicity of selenium. In general, antimutagenicity predominates at physiological levels, while mutagenicity occurs at 3 to 1000 times normal physiological levels.