scholarly journals In Vitro and In Vivo Antibacterial Activities of TAK-083, an Agent for Treatment of Helicobacter pyloriInfection

2001 ◽  
Vol 45 (9) ◽  
pp. 2455-2459 ◽  
Author(s):  
Tsuneo Kanamaru ◽  
Yoshitaka Nakano ◽  
Yukio Toyoda ◽  
Ken-Ichiro Miyagawa ◽  
Mayumi Tada ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Anaerobic Bacteria ◽  
Antibacterial Activities ◽  
Mongolian Gerbils ◽  
Growth Inhibitory ◽  
Growth Inhibitory Activity ◽  
H Pylori ◽  
Aerobic And Anaerobic

ABSTRACT The antibacterial activity of TAK-083 was tested against 54 clinical isolates of Helicobacter pylori and was compared with those of amoxicillin, clarithromycin, and metronidazole. The growth-inhibitory activity of TAK-083 was more potent than that of amoxicillin, clarithromycin, or metronidazole (the MICs at which 90% of the strains are inhibited were 0.031, 0.125, 64, and 8 μg/ml, respectively). The antibacterial activity of TAK-083 was highly selective against H. pylori; there was a >30-fold difference between the concentration of TAK-083 required to inhibit the growth of H. pylori and that required to inhibit the growth of common aerobic and anaerobic bacteria. Exposure ofH. pylori strains to TAK-083 at the MIC or at a greater concentration resulted in an extensive loss of viability. When four H. pylori strains were successively subcultured in the medium containing subinhibitory concentrations of TAK-083, no significant change in the MICs of this compound was observed. TAK-083 strongly inhibited the formation of tryptophanyl-tRNA in H. pylori while exhibiting little effect on the same system in eukaryotes. TAK-083 was efficacious in the treatment of gastric infection caused by H. pylori in Mongolian gerbils. The results presented here indicate that TAK-083 is a promising candidate for the treatment of H. pylori infection.

scholarly journals In Vitro and In Vivo Antibacterial Activities of a Novel Glycylcycline, the 9-t-Butylglycylamido Derivative of Minocycline (GAR-936)

1999 ◽  
Vol 43 (4) ◽  
pp. 738-744 ◽  
Author(s):  
P. J. Petersen ◽  
N. V. Jacobus ◽  
W. J. Weiss ◽  
P. E. Sum ◽  
R. T. Testa
Keyword(s):  
Anaerobic Bacteria ◽  
Tetracycline Resistance ◽  
Protective Effects ◽  
Gram Negative ◽  
E Coli ◽  
Resistance Determinants ◽  
Aerobic And Anaerobic ◽  
Ribosomal Protection

ABSTRACT The 9-t-butylglycylamido derivative of minocycline (TBG-MINO) is a recently synthesized member of a novel group of antibiotics, the glycylcyclines. This new derivative, like the first glycylcyclines, theN,N-dimethylglycylamido derivative of minocycline and 6-demethyl-6-deoxytetracycline, possesses activity against bacterial isolates containing the two major determinants responsible for tetracycline resistance: ribosomal protection and active efflux. The in vitro activities of TBG-MINO and the comparative agents were evaluated against strains with characterized tetracycline resistance as well as a spectrum of recent clinical aerobic and anaerobic gram-positive and gram-negative bacteria. TBG-MINO, with an MIC range of 0.25 to 0.5 μg/ml, showed good activity against strains expressing tet(M) (ribosomal protection), tet(A), tet(B),tet(C), tet(D), and tet(K) (efflux resistance determinants). TBG-MINO exhibited similar activity against methicillin-resistant Staphylococcus aureus (MRSA), penicillin-resistant streptococci, and vancomycin-resistant enterococci (MICs at which 90% of strains are inhibited, ≤0.5 μg/ml). TBG-MINO exhibited activity against a wide diversity of gram-negative aerobic and anaerobic bacteria, most of which were less susceptible to tetracycline and minocycline. The in vivo protective effects of TBG-MINO were examined against acute lethal infections in mice caused by Escherichia coli, S. aureus, andStreptococcus pneumoniae isolates. TBG-MINO, administered intravenously, demonstrated efficacy against infections caused byS. aureus including MRSA strains and strains containingtet(K) or tet(M) resistance determinants (median effective doses [ED50s], 0.79 to 2.3 mg/kg of body weight). TBG-MINO demonstrated efficacy against infections caused by tetracycline-sensitive E. coli strains as well asE. coli strains containing either tet(M) or the efflux determinant tet(A), tet(B), ortet(C) (ED50s, 1.5 to 3.5 mg/kg). Overall, TBG-MINO shows antibacterial activity against a wide spectrum of gram-positive and gram-negative aerobic and anaerobic bacteria including strains resistant to other chemotherapeutic agents. The in vivo protective effects, especially against infections caused by resistant bacteria, corresponded with the in vitro activity of TBG-MINO.

scholarly journals In vitro antibacterial activity of omeprazole and its selectivity for Helicobacter spp. are dependent on incubation conditions.

1996 ◽  
Vol 40 (3) ◽  
pp. 621-626 ◽  
Author(s):  
J E Sjöström ◽  
J Fryklund ◽  
T Kühler ◽  
H Larsson
Keyword(s):  
Antibacterial Activity ◽  
Proton Pump Inhibitors ◽  
Proton Pump ◽  
Bactericidal Activity ◽  
Fetal Calf Serum ◽  
Calf Serum ◽  
Antibacterial Activities ◽  
In Vitro Antibacterial Activity ◽  
H Pylori

Factors affecting the in vitro antibacterial activity of omeprazole were studied. Our data show that 3H-labeled omeprazole covalently bound to Helicobacter pylori and to other gram-negative and gram-positive bacteria. The compound was found to bind to a broad range of proteins in H. pylori, and at pH 5, binding was enhanced 15-fold compared with binding at pH 7. The bactericidal activity correlated to the degree of binding, and at pH 5, a pH at which omeprazole readily converts to the active sulfenamide form, beta-mercaptoethanol, a known scavenger of sulfenamide, and fetal calf serum, to which noncovalent protein binding of omeprazole is known to occur, reduced the level of binding and almost entirely abolished the bactericidal activity. At pH 7 the killing activities of omeprazole and structural analogs (e.g., proton pump inhibitors) were dependent on the time-dependent conversion (half-life) to the corresponding sulfenamide. The bactericidal activity exerted by the sulfenamide form at pH 5 was not specific for the genus Helicobacter. However, in brucella broth at pH 7 with 10% fetal calf serum, only Helicobacter spp. were susceptible to omeprazole, with MBCs in the range of 32 to 64 micrograms/ml, and MBCs for more stable proton pump inhibitors were higher. Wild-type H. pylori and its isogenic urease-deficient mutant were equally susceptible to omeprazole. Thus, the urease is not a lethal target for omeprazole action in H. pylori. In conclusion, the antibacterial activities of omeprazole and analogs are dependent on pH and the composition of the medium used. Thus, at a low pH in buffer, these compounds have a nonselective action, whereas in broth at neutral pH, the mechanism of action is selective for Helicobacter spp.

scholarly journals IN VITRO ANTIBACTERIAL ACTIVITY OF ETHANOLIC EXTRACT OF SEEDPOD AND QUERCETIN OF NELUMBO NUCIFERA GAERTN

2019 ◽  
Vol 12 (1) ◽  
pp. 164
Author(s):  
Ruvanthika Pn ◽  
Manikandan S
Keyword(s):  
Antibacterial Activity ◽  
Ethanolic Extract ◽  
Antibacterial Activities ◽  
Nelumbo Nucifera ◽  
Diffusion Method ◽  
Dependent Manner ◽  
E Coli ◽  
In Vitro Antibacterial Activity

Objective: The objective of the study was to evaluate whether ethanolic extracts of Nelumbo nucifera (EENN) seedpod and quercetin (active component of NN) possess antibacterial proprieties against Gram (-) bacteria such as Escherichia coli and Pseudomonas aeruginosa and Gram (+) bacteria such as Staphylococcus aureus. Methods: Antibacterial activities of EENN seedpod and quercetin were investigated using disc diffusion method, minimum inhibitory concentration against E. coli and P. aeruginosa and Gram (+) bacteria such as S. aureus. Results: The antibacterial activity of both EENN seedpod and quercetin was found to be increased in dose-dependent manner. The maximum zone of inhibition was exhibited by both EENN seedpod and quercetin against E. coli (14 mm and 15 mm) and P. aeruginosa (13 mm and 15 mm). Gram-negative bacteria were more susceptible to the EENN seedpod extract and quercetin than Gram-positive bacteria.Conclusion: The results of the present study suggested that the effect of EENN seedpod and quercetin against the tested bacteria in vitro may contribute to the in vivo activities of the EENN seedpod and quercetin.

scholarly journals Design, Synthesis, and Biological Activity of Novel Myricetin Derivatives Containing Amide, Thioether, and 1,3,4-Thiadiazole Moieties

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3132 ◽  
Author(s):  
Xianghui Ruan ◽  
Cheng Zhang ◽  
Shichun Jiang ◽  
Tao Guo ◽  
Rongjiao Xia ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Pathogenic Bacteria ◽  
Antibacterial Activities ◽  
Xanthomonas Oryzae ◽  
Design Synthesis ◽  
Antiviral Activities ◽  
Potential Alternative ◽  
Better Than

A series of myricetin derivatives containing amide, thioether, and 1,3,4-thiadiazole moieties were designed and synthesized, and their antiviral and antibacterial activities were assessed. The bioassays showed that all the title compounds exhibited potent in vitro antibacterial activities against Xanthomonas citri (Xac), Ralstonia solanacearum (Rs), and Xanthomonas oryzae pv. Oryzae (Xoo). In particular, the compounds 5a, 5f, 5g, 5h, 5i, and 5l, with EC50 values of 11.5–27.3 μg/mL, showed potent antibacterial activity against Xac that was better than the commercial bactericides Bismerthiazol (34.7 μg/mL) and Thiodiazole copper (41.1% μg/mL). Moreover, the in vivo antiviral activities against tobacco mosaic virus (TMV) of the target compounds were also tested. Among these compounds, the curative, protection, and inactivation activities of 5g were 49.9, 52.9, and 73.3%, respectively, which were better than that of the commercial antiviral Ribavirin (40.6, 51.1, and 71.1%, respectively). This study demonstrates that myricetin derivatives bearing amide, thioether, and 1,3,4-thiadiazole moieties can serve as potential alternative templates for the development of novel, highly efficient inhibitors against plant pathogenic bacteria and viruses.

scholarly journals Effects of strontium ions with potential antibacterial activity on in vivo bone regeneration

2020 ◽  
Author(s):  
Nafiseh Baheiraei ◽  
Hossein Eyni ◽  
Bita bakhshi ◽  
Raziyeh Najafloo
Keyword(s):  
Antibacterial Activity ◽  
Bone Formation ◽  
Bone Regeneration ◽  
Bone Repair ◽  
Early Stage ◽  
Antibacterial Activities ◽  
Calvarial Bone ◽  
Alizarin Red

Abstract Background: Bioactive glasses (BGs) have attracted added attention in the structure of the scaffolds for bone repair applications. Different metal ions could be doped in BGs to induce specific biological responses. Among these ions, strontium (Sr) is considered as an effective and safe doping element with promising effects on bone formation and regeneration.Methods: In this experiment, we evaluated the antibacterial activities of the gelatin-BG (Gel-BG) and Gel-BG/Sr scaffolds in vitro. The osteogenic properties of the prepared scaffolds were also assessed in rabbit calvarial bone defects for 12 weeks. Alizarin Red, Hematoxylin & Eosin (H&E) and Masson’s Trichrome staining were performed to assess bone regeneration and the obtained results were compared with those without Sr. Also, histomorphometric data were obtained to evaluate the new bone, residual graft, and connective tissue.Results: Both scaffolds showed in vivo bone formation during 12 weeks with the newly formed bone area in Gel-BG/Sr scaffold was higher than that in Gel-BG scaffolds after the whole period. Based on the histological results, Gel-BG/Sr exhibited acceleration of early-stage bone formation in vivo. The results of antibacterial investigation showed that although both Gel-BG/Sr and Gel-BG effectively inhibited the growth of Escherichia coli (E. coli) but, only Gel-BG/Sr structure could lead to a 3 log reduction in Staphylococcus aureus (S. aureus). Conclusions: Our results confirmed that Sr doped BG is a favorable candidate for bone tissue engineering with superior antibacterial activity and bone regeneration capacity compared with similar counterparts having no Sr ion.

scholarly journals In Vitro and In Vivo Antibacterial Activity of Some Organic and Inorganic Salts Against Asiatic Citrus Canker Agent Xanthomonas Citri Subsp. Citri

2014 ◽  
Vol 2 (6) ◽  
pp. 296
Author(s):  
Vahideh Hasabi ◽  
Hossein Askari ◽  
Seyed Mehdi Alavi ◽  
Masood Soltani Najafabadi
Keyword(s):  
Antibacterial Activity ◽  
Citrus Canker ◽  
Inhibitory Effect ◽  
Inorganic Salts ◽  
Xanthomonas Citri ◽  
Canker Disease ◽  
Growth Inhibitory ◽  
Iron And Zinc

Asiatic citrus canker caused by Xanthomonas citri subsp. citri is becoming a disease of high economic impact, affecting all types of important citrus crops. In this study, the potential antibacterial activity of ten organic and inorganic salts on X. citri subsp. citri and on citrus canker disease development was evaluated. Among the salt compounds, copper, iron and zinc inorganic salts particularly zinc (with the highest diameter of inhibition, the lowest MIC and MBC values and the highest bacterial growth inhibitory effect) had direct antibacterial activity and strongly reduced the development of canker disease and bacterial population of lime plants.

scholarly journals Effects of strontium ions with potential antibacterial activity on in vivo bone regeneration

2020 ◽  
Author(s):  
Nafiseh Baheiraei ◽  
Hossein Eyni ◽  
Bita bakhshi ◽  
Raziyeh Najafloo
Keyword(s):  
Antibacterial Activity ◽  
Bone Formation ◽  
Bone Regeneration ◽  
Bone Repair ◽  
Early Stage ◽  
Antibacterial Activities ◽  
Calvarial Bone ◽  
Alizarin Red

Abstract Background Bioactive glasses (BGs) have attracted added attention in the structure of the scaffolds for bone repair applications. Different metal ions could be doped in BGs to induce specific biological responses. Among these ions, strontium (Sr) is considered as an effective and safe doping element with promising effects on bone formation and regeneration. Methods In this experiment, we evaluated the antibacterial activities of the gelatin-BG (Gel-BG) and Gel-BG/Sr scaffolds in vitro. The osteogenic properties of the prepared scaffolds were also assessed in rabbit calvarial bone defects for 12 weeks. Alizarin Red, Hematoxylin & Eosin (H&E) and Masson’s Trichrome staining were performed to assess bone regeneration and the obtained results were compared with those without Sr. Also, histomorphometric data were obtained to evaluate the new bone, residual graft, and connective tissue. Results Both scaffolds showed in vivo bone formation during 12 weeks with the newly formed bone area in Gel-BG/Sr scaffold was higher than that in Gel-BG scaffolds after the whole period. Based on the histological results, Gel-BG/Sr exhibited acceleration of early-stage bone formation in vivo. The results of antibacterial investigation showed that although both Gel-BG/Sr and Gel-BG effectively inhibited the growth of Escherichia coli (E. coli) but, only Gel-BG/Sr structure could lead to a 3 log reduction in Staphylococcus aureus (S. aureus). Conclusions: Our results confirmed that Sr doped BG is a favorable candidate for bone tissue engineering with superior antibacterial activity and bone regeneration capacity compared with similar counterparts having no Sr ion.

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