The effect of intramuscularly administered immunomodulator, adenylate deaminase (E.C. 3.5.4.6), f... more The effect of intramuscularly administered immunomodulator, adenylate deaminase (E.C. 3.5.4.6), from Penicillium lanoso-viride on the clinical score of acute experimental autoimmune encephalomyelitis (EAE), a T cell-mediated autoimmune disease, was examined by inoculation of guinea pigs with rabbit brain and spinal cord homogenate (encephalitogen) and complete Freund's adjuvant. Adenylate deaminase (ADA) was effective in delaying the onset of clinical disease. ADA inhibited the severity of EAE. There was a significant decrease in clinical signs. A decrease in the number of morbid and dead animals was observed. Of ADA treated animals, 50-80% developed no clinical manifestations of EAE. The optimal version of treatment was a single preventive injection of ADA 1 day before the sensitization and then every second day after immunization for 20 days. ADA treatment of immunized animals diminished the activity of 2', 3'-cyclic nucleotide 3'-phosphodiesterase in the cerebrospinal fluid, as well the amount of complement fixing antiencephalitogenic antibodies in the blood serum. The mechanism of ADA cerebroprotective action is discussed. Significant skin-allergic cross-reaction of delayed-type hypersensitivity between ADA and encephalitogen was observed.
Bacterial infections are a prevalent complication after primary viral respiratory infections and ... more Bacterial infections are a prevalent complication after primary viral respiratory infections and are associated with high morbidity and mortality. Antibiotics are widely used against bacterial respiratory pathogens; however, the rise in antibiotic-resistant strains urges us to search for new antimicrobial compounds, including ones that act synergistically with antibiotics. In this study, the minimal inhibitory (MIC) and minimal bactericidal (MBC) concentrations of a polyphenol-rich complex of green propolis, Tabebuia avellanedae bark, and Olea europaea leaf extracts against Staphylococcus aureus, Haemophilus influenzae, and Klebsiella pneumoniae were determined, followed by an analysis of the synergistic effect with clarithromycin, azithromycin, and amoxiclav (875/125 mg amoxicillin/clavulanic acid). A combination of extracts showed activity against all three bacterial strains, with MIC values ranging from 0.78 to 12.5 mg/mL and MBC values from 1.56 to 12.5 mg/mL. The extracts showe...
Ceramic carriers for immobilization of microorganisms are widely used in wastewater treatment, ai... more Ceramic carriers for immobilization of microorganisms are widely used in wastewater treatment, air biofiltration technologies, etc. The aim of this study was to compare seven different types of ceramic beads fabricated from two types of Devonian clay, in terms of their appropriateness for bacteria cell attachment and further use for soil/air cleaning technologies. The effect of different ceramic beads on the microbial growth and biofilm formation was studied for pure culture Pseudomonas putida MSCL 650 and for bacteria consortium MDK.EKO-7. The highest CFU number recovered from the bead surfaces after 72h cultivation, was in the sets No. 4, 6, and 7, corresponding to one Liepa red and two Planci clay samples, respectively. Besides, a fluoresceine diacetate (FDA) hydrolysis activity of the attached bacteria served as a criterion of biofilm formation. Statistically significant differences of FDA hydrolysis were shown for both, ceramic beads with biomass and without it. Among ceramic beads without biomass, half-spheres of Liepa red clay beads and Planci clay beads significantly differed from other tested samples. These data could point to the notable differences between physical-chemical properties of these beads, which stimulated abiotic FDA hydrolysis. Among ceramic beads with biomass, FDA hydrolysis activity on the half-sphere beads was significantly (p<0.05) higher than that on the surface of the whole sphere beads fabricated from Liepa red clay. SEM micrographs of the bead surface showed uneven distribution of bacteria on the surface. The craters (pores) of ceramic bead seem to be the most appropriate sites for bacteria attachment. Experiments on dehydration of the attached P. putida at 22 °C showed a decrease of cell viability down to zero in 16 days. It was concluded that Liepa red clay and Planci clay are appropriate for carrier fabrication. The quality of ceramic carrier is dependent on the technological process of ceramic production, bead composition and conditions for biofilm formation
Darbā pētītas sešu dažādu RTU Silikātu materiālu institūtā pagatavotu šūnainās keramikas granulu ... more Darbā pētītas sešu dažādu RTU Silikātu materiālu institūtā pagatavotu šūnainās keramikas granulu veidu izmantošanas iespējas biotehnoloģijā. Noskaidrots, ka baktēriju adhēzija notiek uz visām pētītajām granulām, kas iegūtas no Liepas, Lodes un Prometeja atradņu māliem, tomēr tikai Lodes granulas ir piemērotas dzīvu šūnu imobilizācijai. Prometeja mālu granulām ūdens vidē piemīt baktericīda iedarbība. Tā ir mazāk izteikta Liepas granulām, bet nepiemīt Lodes granulām. Darbā skaidroti baktericīdās iedarbības iespējamie mehānismi. Rezultāti liecina, ka no Latvijas māliem iegūtie keramikas materiāli ir daudzveidīgi, un tādēļ tiem ir plašas pielietošanas iespējas biotehnoloģijā
Purpose The manipulation of soil microbiota can involve changes in microbial diversity and microb... more Purpose The manipulation of soil microbiota can involve changes in microbial diversity and microbial activities, and it is carried out for practical purposes. The microbial diversity can be modified by the inoculation of beneficial microorganisms into soil or by agricultural management practices. This study provides information on the influence of introducing beneficial soil microorganisms on soil indigenous microbiota. The aim of this study was to determine how biocontrol and plant growth promoting agents Trichoderma asperellum and Bacillus subtilis and their consortium affect indigenous soil microbiota without placing emphasis on the plant as a determinant of change. Methods Experimental soil samples were treated with B. subtilis and T. asperellum and their consortium. The shift of number of bacterial and fungal CFUs in soil was determined. Biolog EcoPlate assay demonstrated the metabolic activity of microorganisms in soil. The concentration of Trichoderma genus, Firmicutes, Gamma...
The aim of this study was to characterize the digestate from an activated sludge biogas reactor (... more The aim of this study was to characterize the digestate from an activated sludge biogas reactor (IDARS) as an inoculum for enzymatic hydrolysis and biogas production from organic wastes. Aerobic and anaerobic bacteria are represented in IDARS with
Rhizobium leguminosarum biovar viciae is a bacterium, which can establish nodules on roots of leg... more Rhizobium leguminosarum biovar viciae is a bacterium, which can establish nodules on roots of legumes. Rhizobial inoculants are used in agriculture as bio-fertilizers. Peat, clay powder and three kinds of expanded clay were tested for the immobilization of bacteria. The results showed that carrier material influences the success of immobilization and that storage temperature influences the survival. The best results were achieved with maintenance of bacteria in a suspension and immobilization on peat. We recommend storage of rhizobial products at a temperature of −18 °C or 4 °C.
The effect of intramuscularly administered immunomodulator, adenylate deaminase (E.C. 3.5.4.6), f... more The effect of intramuscularly administered immunomodulator, adenylate deaminase (E.C. 3.5.4.6), from Penicillium lanoso-viride on the clinical score of acute experimental autoimmune encephalomyelitis (EAE), a T cell-mediated autoimmune disease, was examined by inoculation of guinea pigs with rabbit brain and spinal cord homogenate (encephalitogen) and complete Freund&amp;amp;#39;s adjuvant. Adenylate deaminase (ADA) was effective in delaying the onset of clinical disease. ADA inhibited the severity of EAE. There was a significant decrease in clinical signs. A decrease in the number of morbid and dead animals was observed. Of ADA treated animals, 50-80% developed no clinical manifestations of EAE. The optimal version of treatment was a single preventive injection of ADA 1 day before the sensitization and then every second day after immunization for 20 days. ADA treatment of immunized animals diminished the activity of 2&amp;amp;#39;, 3&amp;amp;#39;-cyclic nucleotide 3&amp;amp;#39;-phosphodiesterase in the cerebrospinal fluid, as well the amount of complement fixing antiencephalitogenic antibodies in the blood serum. The mechanism of ADA cerebroprotective action is discussed. Significant skin-allergic cross-reaction of delayed-type hypersensitivity between ADA and encephalitogen was observed.
Bacterial infections are a prevalent complication after primary viral respiratory infections and ... more Bacterial infections are a prevalent complication after primary viral respiratory infections and are associated with high morbidity and mortality. Antibiotics are widely used against bacterial respiratory pathogens; however, the rise in antibiotic-resistant strains urges us to search for new antimicrobial compounds, including ones that act synergistically with antibiotics. In this study, the minimal inhibitory (MIC) and minimal bactericidal (MBC) concentrations of a polyphenol-rich complex of green propolis, Tabebuia avellanedae bark, and Olea europaea leaf extracts against Staphylococcus aureus, Haemophilus influenzae, and Klebsiella pneumoniae were determined, followed by an analysis of the synergistic effect with clarithromycin, azithromycin, and amoxiclav (875/125 mg amoxicillin/clavulanic acid). A combination of extracts showed activity against all three bacterial strains, with MIC values ranging from 0.78 to 12.5 mg/mL and MBC values from 1.56 to 12.5 mg/mL. The extracts showe...
Ceramic carriers for immobilization of microorganisms are widely used in wastewater treatment, ai... more Ceramic carriers for immobilization of microorganisms are widely used in wastewater treatment, air biofiltration technologies, etc. The aim of this study was to compare seven different types of ceramic beads fabricated from two types of Devonian clay, in terms of their appropriateness for bacteria cell attachment and further use for soil/air cleaning technologies. The effect of different ceramic beads on the microbial growth and biofilm formation was studied for pure culture Pseudomonas putida MSCL 650 and for bacteria consortium MDK.EKO-7. The highest CFU number recovered from the bead surfaces after 72h cultivation, was in the sets No. 4, 6, and 7, corresponding to one Liepa red and two Planci clay samples, respectively. Besides, a fluoresceine diacetate (FDA) hydrolysis activity of the attached bacteria served as a criterion of biofilm formation. Statistically significant differences of FDA hydrolysis were shown for both, ceramic beads with biomass and without it. Among ceramic beads without biomass, half-spheres of Liepa red clay beads and Planci clay beads significantly differed from other tested samples. These data could point to the notable differences between physical-chemical properties of these beads, which stimulated abiotic FDA hydrolysis. Among ceramic beads with biomass, FDA hydrolysis activity on the half-sphere beads was significantly (p<0.05) higher than that on the surface of the whole sphere beads fabricated from Liepa red clay. SEM micrographs of the bead surface showed uneven distribution of bacteria on the surface. The craters (pores) of ceramic bead seem to be the most appropriate sites for bacteria attachment. Experiments on dehydration of the attached P. putida at 22 °C showed a decrease of cell viability down to zero in 16 days. It was concluded that Liepa red clay and Planci clay are appropriate for carrier fabrication. The quality of ceramic carrier is dependent on the technological process of ceramic production, bead composition and conditions for biofilm formation
Darbā pētītas sešu dažādu RTU Silikātu materiālu institūtā pagatavotu šūnainās keramikas granulu ... more Darbā pētītas sešu dažādu RTU Silikātu materiālu institūtā pagatavotu šūnainās keramikas granulu veidu izmantošanas iespējas biotehnoloģijā. Noskaidrots, ka baktēriju adhēzija notiek uz visām pētītajām granulām, kas iegūtas no Liepas, Lodes un Prometeja atradņu māliem, tomēr tikai Lodes granulas ir piemērotas dzīvu šūnu imobilizācijai. Prometeja mālu granulām ūdens vidē piemīt baktericīda iedarbība. Tā ir mazāk izteikta Liepas granulām, bet nepiemīt Lodes granulām. Darbā skaidroti baktericīdās iedarbības iespējamie mehānismi. Rezultāti liecina, ka no Latvijas māliem iegūtie keramikas materiāli ir daudzveidīgi, un tādēļ tiem ir plašas pielietošanas iespējas biotehnoloģijā
Purpose The manipulation of soil microbiota can involve changes in microbial diversity and microb... more Purpose The manipulation of soil microbiota can involve changes in microbial diversity and microbial activities, and it is carried out for practical purposes. The microbial diversity can be modified by the inoculation of beneficial microorganisms into soil or by agricultural management practices. This study provides information on the influence of introducing beneficial soil microorganisms on soil indigenous microbiota. The aim of this study was to determine how biocontrol and plant growth promoting agents Trichoderma asperellum and Bacillus subtilis and their consortium affect indigenous soil microbiota without placing emphasis on the plant as a determinant of change. Methods Experimental soil samples were treated with B. subtilis and T. asperellum and their consortium. The shift of number of bacterial and fungal CFUs in soil was determined. Biolog EcoPlate assay demonstrated the metabolic activity of microorganisms in soil. The concentration of Trichoderma genus, Firmicutes, Gamma...
The aim of this study was to characterize the digestate from an activated sludge biogas reactor (... more The aim of this study was to characterize the digestate from an activated sludge biogas reactor (IDARS) as an inoculum for enzymatic hydrolysis and biogas production from organic wastes. Aerobic and anaerobic bacteria are represented in IDARS with
Rhizobium leguminosarum biovar viciae is a bacterium, which can establish nodules on roots of leg... more Rhizobium leguminosarum biovar viciae is a bacterium, which can establish nodules on roots of legumes. Rhizobial inoculants are used in agriculture as bio-fertilizers. Peat, clay powder and three kinds of expanded clay were tested for the immobilization of bacteria. The results showed that carrier material influences the success of immobilization and that storage temperature influences the survival. The best results were achieved with maintenance of bacteria in a suspension and immobilization on peat. We recommend storage of rhizobial products at a temperature of −18 °C or 4 °C.
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