Involvement of oxidative stress in bactericidal activity of 2-(2-nitrovinyl) furan against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus

Serum inhibitory and bactericidal titers were measured in nine healthy volunteers following single iv doses of ciprofloxacin 100, 150, and 200 mg. The median peak serum bactericidal titer (5 minutes following completion of a 30-minute infusion) against two highly susceptible strains of Escherichia coli ranged between 1:64 and 1:1024 and titers exceeded 1:8 for six hours for all dose levels. The bactericidal titers against two strains of Pseudomonas aeruginosa and a methicillin-resistant strain of Staphylococcus aureus were considerably lower, the median peak being 1:2 at all dose levels. Measured inhibitory and bactericidal titers at five minutes and one hour postinfusion were significantly greater than those predicted (measured serum ciprofloxacin concentration to minimum inhibitory concentration [MIC] or minimum bactericidal concentration [MBC]) for only one strain of E. coli. Intravenous doses of ciprofloxacin 100–200 mg produce high and sustained serum bactericidal titers against highly susceptible bacteria; considerably lower levels of activity are seen against bacteria having higher MICs and MBCs but still considered susceptible to the drug.

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Mode of action of ceftazidime: affinity for the penicillin-binding proteins of Escherichia coli K12, Pseudomonas aeruginosa and Staphylococcus aureus

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/12.2.119 ◽

1983 ◽

Vol 12 (2) ◽

pp. 119-126 ◽

Cited By ~ 49

Author(s):

Michael V. Hayes ◽

David C. Orr

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Mode Of Action ◽

Binding Proteins ◽

Penicillin Binding Proteins ◽

Escherichia Coli K12 ◽

And Staphylococcus Aureus

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PENGARUH PEMANASAN, TINGKAT KEASAMAN (pH) DAN KONSENTRASI GARAM TERHADAP STABILITAS ANTI BAKTERI EKSTRAK ETANOL KULIT KAYU AKWAY (Drimys piperita Hook f.)

Jurnal Tumbuhan Obat Indonesia ◽

10.22435/jtoi.v12i2.1842 ◽

2019 ◽

Vol 12 (2) ◽

Author(s):

Gino Nemesio Cepeda ◽

Meike Meilan Lisangan ◽

Isak Silamba ◽

Nitia Nilawati ◽

Eka Syartika

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Bacillus Cereus ◽

Inhibitory Concentration ◽

Heating Time ◽

Diffusion Method ◽

Ethanol Extracts ◽

And Staphylococcus Aureus ◽

Agar Well Diffusion Method

ABSTRACT Akway (Drimys piperita) is a woody, evergreen and aromatic plant that belongs to family winteraceae. This plant is used by Sougb tribe lived in Sururey village, District of Anggi, to enhance the vitality of body. The objectives of the research were to determine antimicrobial stability of akway bark extracts influenced by heating time of 100OC, levels of acidity (pH) and salt contents.. Antimicrobial assays were done by using agar well diffusion method against four species of bacteria, i.e. Escherichia coli ATCC25922, Bacillus cereus ATCC10876, Pseudomonas aeruginosa ATCC27853 and Staphylococcus aureus ATCC25923. The results showed that ethanolic extracts of akway bark only inhibited growth of B. cereus and S. aureus with minimum inhibitory concentration 0,99% and 0,89% . The levels of concentration and acidity of ethanol extracts influenced the antimicrobial capacity of extracts.. Whereas heating time on 100OC during 25 minutes and salt contents up to 5% of extract solution did not influence the antimicrobial stability of akway bark extracts. Key words : akway, extracts, antimicrobe, pH, Heating, salt ABSTRAK Akway (Drimys piperita) adalah tumbuhan berkayu, aromatik dan hijau sepanjang tahun dan tergolong dalam suku winteraceae. Tumbuhan ini digunakan oleh Suku Sougb yang bermukim di desa Sururey Distrik Anggi, untuk mengobati malaria dan meningkatkan vitalitas tubuh. Tujuan dari penelitian ini adalah untuk menentukan stabilitas antimikroba ekstrak kulit kayu akway pada waktu pemanasan ekstrak pada 100OC, tingkat keasaman (pH) dan kandungan garam. Pengujian antimikroba dilakukan dengan menggunakan metode difusi agar terhadap empat spesies bakteri yaitu Escherichia coli ATCC25922, Bacillus cereus ATCC10876, Pseudomonas aeruginosa ATCC27853 and Staphylococcus aureus ATCC25923. Hasil menunjukkan bahwa ekstrak etanol kulit kayu akway hanya dapat menghambat bakteri Bacillus cereus dan Staphylococcus aureus dengan konsentrasi hambat minimum masing-masing adalah 0,99% dan 0,89%. Tingkat konsentrasi dan keasaman (pH) mempengaruhi kapasitas antimikroba ekstrak etanol kulit kayu akway. Sedangkan perlakuan pemanasan pada suhu 100OC dengan lama pemanasan sampai dengan 25 menit dan penambahan garam NaCl sampai konsentrasi 5% tidak berpengaruh pada stabilitas antimikroba ekstrak etanol kulit kayu akway.

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