TY - JOUR
T1 - Antimicrobial activity of antibiotics in combination with natural flavonoids against clinical extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae
AU - Lin, Rong Dih
AU - Chin, Yi Ping
AU - Lee, Mei Hsien
PY - 2005/7
Y1 - 2005/7
N2 - Extended-spectrum β-lactamases (ESBLs) are plasmid-mediated class A enzymes commonly found in the family Enterobacteriaceae, mainly in Klebsiella pneumoniae. Flavonoids have also been reported to possess antimicrobial activity. In this study, the in vitro activities of 18 antibiotics and 12 flavonoids against 20 ESBL-producing K. pneumoniae isolates were evaluated. All of these isolates were susceptible to imipenem and cefinetazole, but were resistant to ampicillin, ampicillin/sulbactam, aztreonam, cefazolin, cefoperazone, cefotaxime, ceftazidime, ceftriaxone, cefuroxime, piperacillin and ticarcillin. Susceptibilities to amikacin, amoxicillin/clavulanate, cefoxitin, ciprofloxacin and gentamicin were variable. Myricetin, a flavonol, inhibited ESBL-producing K. pneumoniae isolates at a high minimum inhibitory concentration (MIC) (MIC90 value 256 mg/mL), but exhibited significant synergic activity against ESBL-producing K. pneumoniae in separate combination with amoxicillin/clavulanate, ampicillin/sulbactam and cefoxitin. Because of the low-toxic nature of flavonoids, the combination of antibiotics and flavonoids is a potential new strategy for developing therapies for infections caused by ESBL-producing bacteria in the future.
AB - Extended-spectrum β-lactamases (ESBLs) are plasmid-mediated class A enzymes commonly found in the family Enterobacteriaceae, mainly in Klebsiella pneumoniae. Flavonoids have also been reported to possess antimicrobial activity. In this study, the in vitro activities of 18 antibiotics and 12 flavonoids against 20 ESBL-producing K. pneumoniae isolates were evaluated. All of these isolates were susceptible to imipenem and cefinetazole, but were resistant to ampicillin, ampicillin/sulbactam, aztreonam, cefazolin, cefoperazone, cefotaxime, ceftazidime, ceftriaxone, cefuroxime, piperacillin and ticarcillin. Susceptibilities to amikacin, amoxicillin/clavulanate, cefoxitin, ciprofloxacin and gentamicin were variable. Myricetin, a flavonol, inhibited ESBL-producing K. pneumoniae isolates at a high minimum inhibitory concentration (MIC) (MIC90 value 256 mg/mL), but exhibited significant synergic activity against ESBL-producing K. pneumoniae in separate combination with amoxicillin/clavulanate, ampicillin/sulbactam and cefoxitin. Because of the low-toxic nature of flavonoids, the combination of antibiotics and flavonoids is a potential new strategy for developing therapies for infections caused by ESBL-producing bacteria in the future.
KW - Amoxicillin/clavulanate
KW - Ampicillin/sulbactam
KW - Cefoxitin
KW - Myricetin
KW - Time-kill curves
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U2 - 10.1002/ptr.1695
DO - 10.1002/ptr.1695
M3 - Article
C2 - 16161024
AN - SCOPUS:25444486966
SN - 0951-418X
VL - 19
SP - 612
EP - 617
JO - Phytotherapy Research
JF - Phytotherapy Research
IS - 7
ER -