In-vitro antibacterial activities of rifampicin and cinnamon on methicillin resistant staphylococcus aureus [MRSA]

The present study aimed to investigate antibacterial activity of cinnamon and rifampicin alone and in combination against 45 Methecillin Resistant Staphylococcus aureus isolates [MRSA]. The present study deals with determination of minimal inhibitory concentration [MICs], killing curve and synergism assay of cinnamon extracts and rifampicin for MRSA isolates. The results indicate that MICs of cinnamon aqueous extract mixed with rifampicin for all tested MRSA ranged between 0.2 micro g/ml of rifampicin plus 1.5mg/ml of cinnamon aqueous extract and 16 micro g/ml of rifampicin plus 2mg/ml of cinnamon aqueous extract, that was compared with MICs of rifampicin cinnamon methanol extract, MICs of rifampicin and cinnamon hexane extract combination, rifampicin MIC and cinnamon different extracts MICs. Time-killing curve of rifampicin in combination with cinnamon aqueous extract exhibit zero CFU/ml after 10 hrs incubation period at 37°C that was compared with time-killing curve of rifampicin in combination with cinnamon methanol extract, time-killing curve of rifampicin in combination with cinnamon hexane extract, time-killing curve of rifampicin and time-killing curve of cinnamon different extracts. From our data, we conclude that, cinnamon aqueous extract combined with rifampicin is the best combination to be used as anti-staphylococcal agent

Synthesis of new 4[3H]-quinazolinone derivatives of potential antimicrobial activity

A new series of quinazoline-4[3H]-one derivatives containing hydrazone, thiosemicarbazide, pyrazole moiety and 1,2,4-triazolo[4,3-a]quinazolin-5-[4H]-one derivatives, were prepared in order to study the effect of such combinations on the expected antimicrobial activity. Synthesis of target compounds [3-8] has been achieved through an interaction of the starting 2a or 2b with different alkyl or aryl isothiocyanate. Condensation of 2a or 2b with various aromatic aldehydes or ketones afforded the corresponding hydrazones 9-12. 1- [4-Pyridinyl]-l,2-dihydro-4-phenyl [allyl]-l, 2,4-triazolo [4t 3-a] quinazolin-5- [4H]-one derivatives 13, 14 have been synthesized through reflux of compound 9 or 10 in glacial acetic acid. On the other hand, 1-[3-substituted-3,4-dihydro-4-quinazolinon-2-yl]-3-[4-chlorophenyl] pyrazole-4-car-baldehyde 15 or 16 has also been synthesized through interaction of compounds 11 or 12 with Vilsmeier-Haack reagent. The structures of the new compounds were assigned by spectral and elemental methods of analysis. The synthesized compounds were tested for their in vitro antibacterial and antifungal activities. The tested compounds showed moderate antibacterial activity and weak or no antifungal activity