Synergic interaction between pomegranate extract and antibiotics against Staphylococcus aureus

2005 ◽  
Vol 51 (7) ◽  
pp. 541-547 ◽  
Author(s):  
L C Braga ◽  
A A.M Leite ◽  
K G.S Xavier ◽  
J A Takahashi ◽  
M P Bemquerer ◽  
...  

We evaluated the interaction between Punica granatum (pomegranate) methanolic extract (PGME) and antibiotics against 30 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA). Susceptibility testing of the isolates to PGME and antibiotics was performed by the broth dilution method. Synergic activity was detected between PGME and the 5 antibiotics tested, chloramphenicol, gentamicin, ampicillin, tetracycline, and oxacillin, ranging from 38% to 73%. For some isolates, PGME did not interfere with the action of any of the antibiotics tested. The bactericidal activity of PGME (0.1 × MIC) in combination with ampicillin (0.5 × MIC) was assessed using chosen isolates by time-kill assays, and they confirmed the synergic activity. Using this combination, cell viability was reduced by 99.9% and 72.5% in MSSA and MRSA populations, respectively. PGME increased the post-antibiotic effect (PAE) of ampicillin from 3 to 7 h. In addition, PGME demonstrated the potential to either inhibit the efflux pump NorA or to enhance the influx of the drug. The detection of in vitro variant colonies of S. aureus resistant to PGME was low and they did not survive. In conclusion, PGME dramatically enhanced the activity of all antibiotics tested, and thus, offers an alternative for the extension of the useful lifetime of these antibiotics.Key words: Staphylococcus aureus, antibiotic-resistance, synergy, NorA, Punica granatum.

2021 ◽  
Vol 8 (1) ◽  
pp. 160-165
Author(s):  
Masaaki Minami ◽  
Takafumi Ando ◽  
Hidemi Goto ◽  
Michio Ohta

Mupirocin (MUP) is an effective antibiotic against MRSA. Its bactericidal effect is stable under acid condition. By validating its antibacterial effect of Helicobacter pylori, we try to clarify MUP effect on H. pylori. The present study was conducted to investigate the effect of MUP on clarithromycin (CLR) / metronidazole (MNZ) -resistant and -susceptible strains of H. pylori, the time-kill effect of MUP, and the post antibiotic effect (PAE). We investigated the minimal inhibitory concentration (MIC) and the minimal bactericidal effect (MBC) of MUP against 140 H. pylori, which include clinical strains, ATCC43504, 26695 and J99. Ten of them were CLR -resistant strains and 3 were MNZ-resistant strains. The MIC90 and MBC of MUP on all 140 strains is 0.064 μg / ml, and 0.1 μg / ml, respectively. There were no differences of MUP effect between susceptible and resistant strains either for CLR or MNZ. Time-kill curve test and PAE test of MUP on ATCC43504 were performed. By adding MUP, time-kill curve showed that bacterial quantities decreased in dose and time-dependent manner. No viable colony was found after 12-hour culture with 0.1 μg / ml MUP. The value of PAE is 12. MUP is a potential effective antibiotic for H. pylori even those for CLR / MNZ -resistant strains.


2003 ◽  
Vol 47 (4) ◽  
pp. 1262-1266 ◽  
Author(s):  
Matthew R. Moore ◽  
Françoise Perdreau-Remington ◽  
Henry F. Chambers

ABSTRACT Heterogeneous resistance to vancomycin is thought to precede emergence of intermediate susceptibility to vancomycin in Staphylococcus aureus, but the clinical significance of heterogeneous resistance is unknown. Paired S. aureus isolates from a patient with endocarditis who relapsed after vancomycin treatment were tested for heterogeneous resistance to vancomycin. The pretreatment and the relapse clinical isolates (strains SF1 and SF2, respectively) were genotyped by pulsed-field gel electrophoresis. Susceptibility to vancomycin was assessed by the broth dilution method, population analysis, and time-kill studies and in the rabbit model of endocarditis. Strains SF1 and SF2 had similar genotypes, and the vancomycin MICs for the strains were ≤2 μg/ml. SF2 exhibited heterogeneous resistance to vancomycin. Vancomycin eradicated SF1 in the rabbit model of endocarditis, while SF2 persisted at pretreatment levels. Vancomycin treatment failure in this patient with endocarditis was attributable to heterogeneous resistance to vancomycin.


Author(s):  
Ilham Boulhissa ◽  
Abdelouahab Chikhi ◽  
Abderrahmane Bensegueni ◽  
Mohammad Ahmad Ghattas ◽  
El Hassen Mokrani ◽  
...  

Background: View to its interesting role in the peptidoglycan biosynthesis pathway the enzyme UDP-N- acetylglucosamine enolpyruvyl transferase is an attractive target to develop new antibacterial agents, it catalyzes the first key step of this pathway and its inhibition leads to the bacterial cell death. Fosfomycin is known as the natural inhibitor of MurA. Objective: Call new inhibitors of MurA by virtual screening of different chemical compounds libraries, and test the best scored “virtual hits” against three pathogenic bacteria: Escherichia coli, Bacillus subtilis, and Staphylococcus aureus. Methods: A Virtual screening of the structural analogues of fosfomycin downloaded from PubChem database was performed on one side and of the French National Chemical Library as well as using ZINC database to identify new structures different from fosfomycin on the other, FlexX was the software used for this study. The antibacterial testing was divided into methods: disk diffusion and broth dilution. Results: A set of virtual hits was found with better energy score than that of fosfomycin, seven between them were tested in vitro. Therefore, disk diffusion method explored four compounds exhibited antibacterial activity: CID-21680357 (fosfomycin analogue), AB-00005001, ZINC04658565, and ZINC901335. The testing was continued by broth dilution method for both compounds CID-21680357 and ZINC901335 to determine their minimum inhibitory concentrations, and ZINC901335 had the best value with 457µg/ml against Staphylococcus aureus. Conclusion: Four compounds were found and proven in silico and in vitro to have antibacterial activity: CID-21680357, AB-00005001, ZINC04658565, and ZINC901335.


2021 ◽  
Vol 71 (5) ◽  
pp. 209-214
Author(s):  
Agus Syahrurachman ◽  
Atna Permana

Introduction: There is no susceptibility data of E. coli and K. aeromobilis in Indonesia, even data regarding minimal inhibitory concentration (MIC)-based susceptibility of E. coli and K. aeromobilis towards single antibiotic or combination of fosfomycin (FOS) and sulbactam-cepoferazone (SUL-CPZ) is very scarce, even though the data is required by clinicians. Methods: A descriptive observational study was carried out at the Microbiology Clinical Laboratory of the Faculty of Medicine, Universitas Indonesia. Thirty strains each of clinical isolates of E. coli and K. aeromobilis were subjected to MIC determination against FOS and SUL-CPZ. For susceptibility criteria, we adopted the Eucast guideline. The synergism of the combined antibiotics was determined by checkerboard titration. One strain of E. coli and K. aeromobilis showing a synergistic and independent effect against the combined antibiotics was subjected to a time-kill assay. The post-antibiotic effect (PAE) was determined on a strain of E. coli showing synergism against the combined antibiotics. Results: The MIC level of all strains decreased when the bacteria were exposed to the combined antibiotics. Synergism was observed in 53.3% of E. coli and 56.8% of K. aeromobilis. No antagonism was observed. Higher bacterial death during the first four hours occurred with the isolate, showing synergism compared to the isolate showing an independent effect. The PAE of E. coli was longer when exposed to combined antibiotics. Conclusion: In vitro synergism of FOS and SUL-CPZ was observed in the majority of isolates and could be used as the basis for further research on empirical treatment


2007 ◽  
Vol 56 (1) ◽  
pp. 71-76 ◽  
Author(s):  
Xin-Yi Yang ◽  
Cong-Ran Li ◽  
Ren-Hui Lou ◽  
Yue-Ming Wang ◽  
Wei-Xin Zhang ◽  
...  

Lysostaphin is a glycylglycine endopeptidase. It cleaves the pentaglycine cross-bridge structure unique to the staphylococcal cell wall and is considered to be a potential drug for Staphylococcus aureus. In the present study, the in vitro activity of recombinant lysostaphin was investigated in 257 S. aureus isolates collected from hospital patients in Beijing, China, by determination of MIC and minimum bactericidal concentration (MBC) and a time–kill curve test. An agar dilution method was used for MIC determination in all of the isolates and a macrobroth dilution method was employed to verify MIC values for a subset of the isolates. All of the S. aureus strains were sensitive to the recombinant lysostaphin with MICs ranging from 0.03 to 2 μg ml−1 in the agar dilution assay. The antibacterial activity of lysostaphin was greater than that of vancomycin and other reference agents. For most of the isolates, the MICs from the agar dilution method were higher than those from the broth dilution method. The MBCs of lysostaphin in the test isolates were between 1- and 8-fold higher than their MIC values. Bactericidal activity (>99.9 % reduction) was observed after 2 h exposure of the isolates to lysostaphin at concentrations of ⩾0.5 MIC. Lysostaphin showed a rapid bactericidal activity against the test strains of meticillin-susceptible S. aureus and meticillin-resistant S. aureus. Its activity at ⩾0.5 MIC was sustained for at least 6 h. These results will be informative for the clinical application and evaluation of lysostaphin.


2001 ◽  
Vol 45 (12) ◽  
pp. 3422-3426 ◽  
Author(s):  
Siddhartha Roychoudhury ◽  
Tracy L. Twinem ◽  
Kelly M. Makin ◽  
Mark A. Nienaber ◽  
Chuiying Li ◽  
...  

ABSTRACT The in vitro development of resistance to the new nonfluorinated quinolones (NFQs; PGE 9262932, PGE 4175997, and PGE 9509924) was investigated in Staphylococcus aureus. At concentrations two times the MIC, step 1 mutants were isolated more frequently with ciprofloxacin and trovafloxacin (9.1 × 10−8 and 5.7 × 10−9, respectively) than with the NFQs, gatifloxacin, or clinafloxacin (<5.7 × 10−10). Step 2 and step 3 mutants were selected via exposure of a step 1 mutant (selected with trovafloxacin) to four times the MICs of trovafloxacin and PGE 9262932. The step 1 mutant contained the known Ser80-Phe mutation in GrlA, and the step 2 and step 3 mutants contained the known Ser80-Phe and Ser84-Leu mutations in GrlA and GyrA, respectively. Compared to ciprofloxacin, the NFQs were 8-fold more potent against the parent and 16- to 128-fold more potent against the step 3 mutants. Mutants with high-level NFQ resistance (MIC, 32 μg/ml) were isolated by the spiral plater-based serial passage technique. DNA sequence analysis of three such mutants revealed the following mutations: (i) Ser84-Leu in GyrA and Glu84-Lys and His103-Tyr in GrlA; (ii) Ser-84Leu in GyrA, Ser52-Arg in GrlA, and Glu472-Val in GrlB; and (iii) Ser84-Leu in GyrA, Glu477-Val in GyrB, and Glu84-Lys and His103-Tyr in GrlA. Addition of the efflux pump inhibitor reserpine (10 μg/ml) resulted in 4- to 16-fold increases in the potencies of the NFQs against these mutants, whereas it resulted in 2-fold increases in the potencies of the NFQs against the parent.


2017 ◽  
Vol 10 (2) ◽  
pp. 152-157 ◽  
Author(s):  
Grazielle Millo ◽  
Apa Juntavee ◽  
Ariya Ratanathongkam ◽  
Natsajee Nualkaew ◽  
Peerapattana, Jomjai ◽  
...  

ABSTRACT Aim This study evaluated the in vitro antibacterial effects of the formulated Punica granatum (PG) gel against Streptococcus mutans, Streptococcus sanguinis, and Lactobacillus casei. Materials and methods The PG extract was dissolved in water at 500 mg/mL. High performance liquid chromatography (HPLC) was used for identification and quantification of chemical marker punicalagin. Minimum bactericidal concentration (MBC) and time-kill assay (TKA) were investigated. Antibacterial activities of the formulated PG gel, 2% chlorhexidine (CHX) gel and blank gel were tested by measuring the zones of inhibition through agar well diffusion method. Results The HPLC results showed presence of punicalagin at 2023.58 ± 25.29 μg/mL in the aqueous PG extract and at 0.234% (w/w) in the formulated PG gel. The MBC for S. mutans, S. Sanguinis, and L. casei were 250, 125, and 500 mg/mL respectively. The TKA of 500 mg/mL aqueous PG extract showed total inhibition of S. mutans, S. Sanguinis, and L. casei at 6, 1, and 24 hours contact time respectively. Agar well diffusion revealed that for S. mutans, CHX gel > PG gel > blank gel; for S. sanguinis, CHX gel = PG gel > blank gel; for L. casei, CHX gel > PG gel = blank gel. Comparison of the PG gel potency showed that S. sanguinis = S. mutans > L. casei. Conclusion The PG gel equivalent to 0.234% punicalagin (w/w) inhibited S. mutans and S. sanguinis but not L. casei within 24 hours incubation period and has the potential to be used for caries prevention. How to cite this article Millo G, Juntavee A, Ratanathongkam A, Nualkaew N, Peerapattana J, Chatchiwiwattana S. Antibacterial Inhibitory Effects of Punica Granatum Gel on Cariogenic Bacteria: An in vitro Study. Int J Clin Pediatr Dent 2017;10(2):152-157.


Sign in / Sign up

Export Citation Format

Share Document