[STUDY OF COMPOSITION OF PLANT EXTRACTS, POSSESSING ANTIMICROBIAL EFFECT AGAINST VIBRIO CHOLERAE EL TOR, USING HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY].

AIM: Study the composition of plant extracts using high-performance liquid chromatography. (HPLC) and evaluation of their antimicrobial effect against Vibrio cholerae El Tor. MATERIALS AND METHODS: Qualitative and quantitative composition of plant extracts was studied using HPLC. Determination of sensitivity of microorganisms to plant extracts was carried out by diffusion into agar method and serial dilutions method. RESULTS: Antibacterial effect of water, water-alcohol and acetone extracts of roots of Limonium gmelinii L., Berberis vulgaris L. and Glycyrrhiza glabra L. was studied. The most effective methods of extraction of biologically active substances, possessing antimicrobial effect against various strains of V. cholerae El Tor, were determined. CONCLUSION: The use of HPLC allowed to establish the presence of catechines, alkaloids protoberberines and glycyrrhizic acid in xtracts, possessing antimicrobial effect against V. cholera El Tor strains.

[The development of polymer immunoglobulin preparations to identify different serovars legionella pneumophilia in reaction of slide-agglutination].

The article deals with the results of study targeted to develop polymer diagnostic preparation to identify epidemically significant serogroups Legionella pneumophilia. The preparation combines rate of record (1-5 min) of reaction of paragglutinining preparations with color visualization and demonstrative of reaction of volume agglomeration with polymer diagnosticums. The specially synthesized polymer microspheres were sensibilized with serums enriched with antibodies to lipopolysaccharide of corresponding serovar L. pneumophilia. The derived immunoglobulin diagnostic preparations detect agent of legionellesis in the reaction of slide-agglutination on glass during 1-5 min. The polymer diagnostic preparations provide positive reaction with culture of corresponding serovar and no reaction with other gomologic and geterologic agents of infectious diseases.

[Comparative study of the biological properties of various nutrient media used for the isolation of Legionella pneumophila].

Three diagnostic selective media used for the isolation of Legionella pneumophila were compared. These included BCYEAalpha (Oxoid, a reference medium), BCYEAalpha (Hi Media), and elective legionellosis medium (ELM) developed at the Rostov-on-Don Research Institute for Plague Control. The virulent L. pneumophila strain Philadelphia-1 (LD50 was 10(5) CFU for guinea-pigs) was used a test culture. The susceptibility of the media was determined, by culturing 10(-6) and 10(-7) dilutions of the suspension of the macerated Legionella-infected guinea-pig spleen, as well as the suspension of a culture of this strain (100 CFU) and 6 L. pneumophila cultures freshly isolated from water. The BCYEAalpha (Oxoid) and ELM media demonstrated the similar growth characteristics (chi2 < 0.7; p = 0.05) while the BCYEAalpha (Hi Media) medium showed a low susceptibility. The BCYEAalpha (Oxoid) and ELM media were first found to be successful in detecting Legionella in viable, but nonculturable state, induced by the following factors: 1) starvation in distilled water; 2) exposure to hydroquinone (oxidative shock, and 3) elevated temperature (56 degrees C). The BCYEAalpha (Oxoid) and EML media did not differ either in their ability to suppress extraneous microflora and to maintain stable initial pH under the conditions of incubation of culture plates, as well as in their Na+ concentration (15-19 mmol/l). However, the BCYEAalpha (Oxoid) medium exceeded the ELM one in the growth rate and diameter of Legionella colonies. Two L. pneumophila cultures were isolated in the BCYEAalpha (Oxoid) and EML media used in the field experiment studying 15 water samples from different hot water supply systems. Thus, the conclusion can be drawn that the EML medium is comparable with the reference BCYEAalpha (Oxoid) medium in its susceptibility and ability to detect Legionella in both vegetative and viable, but nonculturable states and is suitable for practical application.

[Study of Legionella pneumophila strains isolated from environmental objects].

The paper presents the results of studying the biological properties of Legionella pneumophila strains isolated from environmental objects. Elective legionellosis medium (ELM) has been found to be suitable for the isolation of the causative agent from the starting material and to be as sensitive as CYE (Oxoid company) containing growth and selective additives. Polymerase chain reaction (PCR) with a home-produced commercial test system used to detect L. pneumophila DNA enables identification of the causative agent, including its species. Hyperimmune sera against L. pneumophila 1-7 serogroups used in slide-agglutination and agglutination, as well as a series of co-agglutinating diagnosticums for legionellosis 1-7 serogroups make it possible to identify even the serogroups of L. pneumophilla. Comparative analysis of the virulence of L. pneumophila cultures in vivo and in vitro allows recommendation that practical laboratories should employ a simple NaCl resistance test, which can be used as a guide virulence test.

[Dimorphism in the fungus Coccidioides immitis Rixford et Gilchrist under the action of saprophytic bacilli]. / Dimorfizm griba Coccidioides immitis Rixford et Gilchrist pod vozdeistviem batsill-saprofitov.

It is shown that there are specific substances produced and secreted into the environment by saprotrophic bacilli. These inhibit the growth of the coccidioidal fungus in its mycelial form and some cells are converted into the yeast form, which leads to the destruction of the fungi (in natural environment) or, if the conditions allow, to their growth in the yeast form. This phenomenon, existence of a large amount of bacilli antagonistic to Coccidioides immitis, may be one of reasons why the latter has not been isolated so far from the soil in the territory of the USSR.

[The action of bacillary inhibitory substances on human-pathogenic, phytopathogenic and saprotrophic fungi]. / Deistvie batsilliarnykh ingibiruiushchikh veshchestv na patogennye dlia cheloveka, fitopatogennye i saprotrofnye griby.

The study has shown that the growth of many soil fungi is inhibited by the effect of substances which are produced into the environment by some bacilli-saprotrophs. Besides, these substances can bring about a dimorphism of the Trichoderma, Blastomyces, Emmonsia, Alternaria and Verticillium fungi from the mycelial form into the yeast form, which results in the death of the fungi. The existence of bacilli capable of producing the inhibitory substances, in the soil in the territory of the USSR may explain, to a certain extent, the absence of the coccidioidomycosis and North American blastomycosis agents pathogenic for people and many animals.

[Peptidase activity of Coccidioides immitis]. / Peptidaznaia aktivnost' Coccidioides immitis.

Glycyl-L-leucinehydrolase consisting of three molecular units was extracted from C. immitis solid cultural medium. During fractionation in polyacrylamide gel of the enzyme-containing extract a 50-fold purification of the enzyme isoform with molecular weight 12,800 is achieved. The enzyme is heat-stable, active in the narrow pH range and hydrolizes peptide bonds containing glycine. Its activity is not inhibited by none of the protease inhibitors tested.