Determination of Bacterial Concrete Strength Using Bacillus Subtilis and Lightweight Expandable Clay Aggregate

This study examines the impact of bacterial concrete on strength and self-healing. Bacterial concrete has better compressive strength, permeability, corrosion resistance, chemical precursors, alkalinity resistance, and mechanical stress. Bacillus subtilis calcium lactate and spore powder effects are explored in this study, and the influence of this bacterial form on strength and self-healing capacity to crack repair. The Bacillus subtilis concentration 105 cells/mL is used in concrete with calcium lactate 0.3% of cement. In another trial, calcium lactates 0.3% and spore powder 0.5% of cement with Bacillus subtilis concentration of 105 cells/mL and lightweight expandable clay aggregate (LECA) is 30% replaced to the coarse aggregate used in concrete respectively. The conventional concrete and bacterial concrete cubes were molded with dimensions of 150 mm x 150 mm x 150 mm, cylinders with dimensions of 100 mm x 200 mm, and a beam with dimensions of 100 mm x 100 mm x 500 mm. These specimens were evaluated after 7 and 28 days of cure. The compressive, split tensile, and flexural strength of bacterial concrete was raised by 23%, 8%, and 7%, respectively when compared to conventional concrete. Thus, the experimental findings reveal that Bacillus subtilis at 105 cells/ml cells with 0.3% calcium lactate has a substantial impact on the strength and self-healing of bacterial concrete.

Number of T- and B-lymphocytes and their functional activity in the blood of common carps affected by Aeromonosis, and in the treatment of probiotic Enteronormin

Fish bacterial infectious diseases are a significant problem for aquaculture, often leading to massive fish deaths and significant economic losses. For fish treatment often used antibacterial drugs: nitrofuran, antibiotics, feed antibiotics, as well as dyes. Finding effective drugs and studying their effects on the body of fish are relevant. Nowadays, different groups of substances, including probiotics, are offered as an alternative to increase the growth of animals and to combat pathogens. Here are the results of studies of the influence of the probiotic drug "Enteronormin" on the indicators that characterize the status of T- and B-cell immunity of carp affected by bacterial Aeromonosis. Enteronormin is a probiotic supplement , wich contains a bacteria complex - Enterococcus spp, Bacillus subtilis spp, Lactobacillus spp; and excipients - chitosan, peptone enzymatic and ground sugar (RP № BB-00427-02-12 dated 13.04.2012). The research was conducted under the conditions of aquariums at the Lviv Research Station of the Institute of Fisheries of NAAS. The control group, which consisted of clinically healthy fish, received only 3% starch suspension, the first experimental group (D1) - Aeromonosis affected carps who were given only 3% starch suspension, the second experimental group (D2), which consisted of carps affected Aeromonosis, through the probe within 7 days was administered the drug "Enteronormin", at the rate of 2 mg per 1 kg of fish weight, in the composition of 3% starch suspension. Before feeding for the carp drug was activated for 14-16 hours water enriched with Iodine and Selenium ions in the Jodis + Se form (TU U 15.7-30631018-011: 2011). It is established that the disease of carp on Aeromonosis leads to changes in the number and functional activity of immunocompetent blood cells. The inhibition of lymphocytogenesis and functional activity of immunocompetent cells in carp blood in a disease associated with the bacterial form of aeromonosis was ascertained. The use in the experimental carps group in the composition of 3% starch suspension of the drug "Enteronormin" had a normalizing effect on the state of T-cell specific protection, but did not significantly affect the amount of EAC-RUL and their functional activity. Key words: fish, carp, aeromonosis, probiotics, Enteronormin, T-lymphocytes, B-lymphocytes.

Effect of Four Essential Oils on Cells Release Membrane and Biofilm Formation of Clinical Bacterial Isolated From Oral Infection

Background: Bacterial biofilms forming are current resistant bacterial form to the treatment of oral diseases that colonizes in the gingival and sub-gingival regions of the mouth. The present study aims to screen the anti-biofilm potential and evaluate the effect of four essential oils on cells release membrane. Methods: Seven type isolate bacteria obtained during previous work were screen to select those who had ability to form biofilm using Congo Red Agar method, tube method and crystal violet method. The inhibitory parameter of biofilm forming was determine using microtiter plate method. The effect of essential oil on cell membrane release of each selected bacterial was put in evidence by measuring cellular material that absorb at 260 nm and 280 nm after 0 min, 30 min and 60 min of exposure and confirm by measuring DNA, RNA and proteins release by treated cells on extracellular medium using Nanodrop 1000 spectrophotometer. Results: The crystal violet method shows twelve (12) strong, five (05) moderate and five (05) weak biofilm forming bacteria. The anti-biofilm activity against the oral bacteria who shown that most of essentials oils have activity on different biofilm formation and the MICs ranged from 0.31 mg/mL to 1.25 mg/mL. Concentration of intracellular material released in extracellular medium ranged from 186,56 ± 2,35 ng/µL to 766,6 ± 2,84 ng/µL for DNA, 158,06 ± 1,87 ng/µL to 628,53 ± 2,05 ng/µL for RNA and 695,9 ± 2,11ng/µL to 1125,23 ± 2,15 ng/µL for proteins. Conclusion: This study demonstrates that the selected EOs have a significant anti-biofilm activity, acting on the cell surface and causing the disruption of the bacterial membrane. These EOs are interesting alternative to conventional antimicrobials for the control of oral microorganisms. Keywords: Anti-biofilm activity, Biofilm, oral diseases

BIOLOGICAL ACNIVITY OF L-FORM OF MYCOBACTERIA TUDERCULOSIS OF CATTLE TRANSFORMED UNDER THE INFLUENCE OF ANTIBACTERIAL PREPARATIONS

The sensitivity of Mycobacterium bovis, strain Vallee, №8 to the action of L-transformation of penicillin, lisozimum and their combinations was shown resulting in reduced pathogenic and sensibilizogenic properties of L-form of Mycobacterium bovis, strain Vallee in comparison with the bacterial form. Thus, the appearance of the hypersensitivity of delayed type with lower intensity as well as slow course of infectious process with limited specific injury of laboratory animals viscera were observed.

Comparison of quantitative and qualitative antibody-producing cell responses to lipopolysaccharide in cell walls of the bacterial form and in membranes of the protoplast L-form of Proteus mirabilis

Membranes of the stable protoplast L-form of Proteus mirabilis strain VI were highly immunogenic carriers of lipopolysaccharide when compared with the immune responses to lipopolysaccharide contained in cell walls of the bacterial form of this organism.

Bacterial and Bacteroid Properties of Mutants of Rhizobium Trifolii Strain T1 Uncoupled in Oxidative Phosphorylation

Using the neomycin-resistance selection technique, mutants uncoupled in oxidative phosphorylation were isolated in R. tri/olii strain Tl. These mutants had no detectable ATP-synthesizing activity and between 8 and 20% of the ATP-degrading activity of their parent strain in the bacterial form. The mutants formed nitrogen-fixing nodules on red, white, and subterranean clovers, and bacteroids isolated from white clover nodules had a high level of ATPase activity of about 70% of that found in bacteroids of their parental strain. The possibility that a new ATPase complex is synthesized when the bacteria differentiate to form bacteroids within the nodule is discussed.

Survival and reversion of a stable L form in soil

The stable L form of Agromyces ramosus reverted to a bacterial form when incubated in sterilized soil. The cellular and colonial morphology of this bacterial form resembled that of the original parent bacterial form. The two forms differed, however, in that the revertant maintained its bacterial form when transferred onto a low-salt (NaCl) medium but was virtually completely induced into the L-form state on a high-salt medium. The original parent bacterial form was not sensitive to salt. The possibility is discussed that an L-form ↔ bacterial-form cycle for this bacterium might occur naturally in soil. This cycle would be mediated by fluctuations in local salt concentrations in the soil.