[Influence of cryopreservation and lyophilization on exopolysaccharide synthesis and viability of Xanthomonas campestris pv. campestris IMV B-7001].

It is shown, that the producer of exopolysaccharides Xantomonas campestris pv. campestris IMV B-7001 is more sensitive to freeze-drying, than to freezing-thawing and keeps stable morphological properties. Predicted preservation of viability is within the limits of 2-8 years at -70 degrees C and exceeds 30 years at -135 degrees C and freeze-drying. Results of the latter essentially depend on the medium composition and storage conditions. Synthesis of exopolysaccharides at preservation is kept, showing the tendency to temporal increase of productivity at regeneration from anabiosis. Such stimulating effect is more expressed at cryopreservation and depends on the cryoprotector and freezing temperature. The investigated cryoprotectors are arranged in a line according to their efficiency: 10% sucrose +1% gelatin > or = 10% glycerin > 5% dimethylsulfoxide > 4% ethylene glycol.

[The antagonistic properties of bacteria isolated from the digestive tract of female mink housed in the area of the Chernobyl Atomic Electric Power Station]. / Antagonisticheskie svoistva bakterii, vydelennykh iz pishchevaritel'nogo trakta samok norok, soderzhashchikhsia v zone ChAES.

Differences in species composition, number and level of antagonistic activity of bacteria isolated from the digestive tract of Chernobyl female minks of various age and with different immunological state have been established. Prevalence of anaerobes (bifidobacteria) and microaerophils (lactic acid bacteria) with the increase of microorganisms concentration along the channel: stomach, small and large intestine (10(7)-10(10)/g) was found in all the departments of digestive tract of minks. Among the identified lactic-acid bacteria Lactobacillus helveticus (10(7)-10(8)/g) prevailed in the stomach of the studied female minks, L. coryniformis (10(9)-10(10)/g) in the small intestine, L. casei (10(10)/g) in the large one. Antagonistic activity was most expressed in the strains of L. helveticus and L. casei, isolated from the younger (1.5 year-old) minks. Enterococcus faecalis isolated from the stomach of 1.5 year-old female minks was distinguished by the greatest antagonistic activity among identified enterococci. Strains of E. faecium isolated from the thin intestine of the young female minks (1.5 year-old) and from the large intestine of more nature animals (2.5 years) who received thymogen were characterized by the most expressed antibiosis among enterococci isolated bacteria a conclusion was made that the mechanisms of inhibitory effect of the studied microorganisms are underlied by not only their capacity to form organic acids but also by the capacity to produce antibiotic products.

[The antagonistic properties of microaerophilic bacteria isolated from the human and mink digestive tracts]. / Antagonisticheskie svoistva mikroaérofil'nykh bakterii, vydelennykh iz pishchevaritel'nogo trakta cheloveka i norok.

Study of antagonistic properties of microaerophilic bacteria isolated from human and mink gastroenteric tract have helped to establish differences in species composition, quantity and level of antagonistic activity of the studied microorganisms in respect to pathogenic microflora. It is shown that lactic acid bacteria identified as Lactobacillus fermentum and L. reuteri prevail among the strains isolated from the stomach and thin intestine of minks kept in the 30-km zone of Chernobyl NPP. Species composition of microaerophilic bacteria isolated from the digestive tract of the control minks is more variable. Antagonistically active bifidobacteria prevail in large intestine of experimental and control animals. Strains of lactic acid bacteria with the expressed antagonistic activity belonging to L. bavaricus, L. reuteri, L. coryniformis and L. maltaromicus have been found parallel with such known producers of antibiotic-like substances as L. fermentum. L. acidophilum. Streptococcus faecalis and bifidobacteria. L. maltaromicus most frequently occurred among antagonistically active strains revealed in feces of people which stayed in the zone of liquidation of the Chernobyl accident. Microaerophilic strains of bacteria (lactic acid, bifidobacteria and enterococci) manifest the expressed antagonistic activity connected with the capacity to not only acid formation but also to accumulation of antibiotic products of unknown nature. A strain of lactic acid bacteria L. fermentum 91 has been isolated from the contents of human gastroenteric tract. These bacteria are distinguished by most expressed and stable antagonism and characterized by the lack of pathogenicity in respect of albino mice that may be used to raise the microorganism resistance to gastric diseases.

[A microflora study of the gastrointestinal tract of mink housed within and outside of the area of the Chernobyl Atomic Electric Power Station]. / Issledovanie mikroflory zheludochno-kishechnogo trakta norok, soderzhashchikhsia v zone ChAES i vne ee.

Quantitative differences in the content of lactic acid bacteria isolated from the content of the stomach, small and large intestine have been established when studying microflora of the gastrointestinal tract of minks kept in the 30-kilometer zone of the Chernobyl NPP (experimental animals) and at the Cherkassy fur farm (control animals). Obligate heterofermentative species of lactic acid bacteria related to Lactobacillus fermentum and L. reuteri prevailed in the stomach of experimental minks. Species composition of lactic acid bacteria isolated from the stomach of the Cherkassy minks is characterized by the availability of both obligate and facultative heterofermentative species of bacteria--L. bavaricus, L. coryniformis, L. reuteri and of obligate homofermentative bacteria--L. salivarius and L. jensenii. In limiting dilutions (10(-9)-10(-10)) of the content of small intestine of the control minks one could find bacteria of L. coryniformis species and representatives of obligate heterofermentative bacteria--L. confusus and L. fermentum that is 1-2 orders higher then in the experimental minks. Both lactic acid bacteria and bifidobacteria (the latter up to 10(+9) cells/g of the content) were isolated from the lower departments of small and large intestine of the Chernobyl and Cherkassy minks. Among the species of lactic acid bacteria isolated from the experimental animals homofermentative species (L. acidophilus, L. sharpeae) and, heterofermentative (L. confusus, L. fermentum) in the control were found.(ABSTRACT TRUNCATED AT 250 WORDS)

[The intestinal microflora of persons subjected to a radiation lesion]. / Kishechnaia mikroflora liudei, podvergshikhsia radiatsionnomu porazheniiu.

The content of large intestine has been studied in persons exposed to radiation injury in consequence of the accident at the Chernobyl Atomic Power Plant. It is stated that bifidobacteria (10(7)-10(10) cells in 1 g of feces) prevailed (as in healthy people), Bifidobacterium indicum being a dominating species. Amount of lactic-acid bacteria in 1 g of defecations of examined patients was within the range of 10(6)-10(9) cells and in certain persons it reached 10(10) cells (primarily fecal Enterococci). A considerable amount of patients with acute radiation sickness of the 3d degree had in their intestine 10(9)/g of lactic-acid bacteria, Lactobacillus casei and L. plantarum prevailing there. The frequency of yeast isolation from defecations of patients constituted 83%, while the number of cells in 1 g of feces--from 10 to 10(4). Yeast of the Candida genus, mainly Candida parapsilosis, prevailed. The species composition of isolated microorganisms has no substantial differences from microcenosis of healthy people. The content of intestine of persons suffered from radiation is characterized only by greater amount of lactic-acid bacteria and enterococci as compared with healthy adults.