Cinnamaldehyde and functional isomers: structure-activity analysis and antibacterial properties mediated through dihydropteroate synthase in Gram +/- bacteria.
Cinnamon oil has been used for thousands of years for medicinal purposes. More recently, it has been shown to have antidiabetic, antimicrobial, anti-inflammatory, and antibacterial properties. We have investigated the antibacterial properties of cinnamaldehyde, a component of cinnamon oil, against two gram-positive (Bacillus cereus and Bacillus megaterium) and two gram-negative bacteria (Escherichia coli and Serratia marcescens) which are facultative anaerobic. When compared to other functional isomers, the aldehyde group and length of the aryl chain are important factors in determining antibacterial activity. Further, additions to the aromatic ring show small differences while additions to the aryl chain significantly abolish the effects. Together, these results suggest a “lock and key”, leading us to hypothesize that the mechanism of action of cinnamaldehyde is an enzyme/receptor mediated event. To test this hypothesis, we established bacterial growth curves to show cinnamaldehyde is bacteriostatic rather than bactericidal. Additionally, in our pharmacological studies, we have shown for the first time that cinnamaldehyde acts as an inhibitor of dihydropteroate synthase, a key component of folate metabolism. Results show that cinnamaldehyde is in competition with known substrates. As dihydropteroate synthesis is only found in microorganisms, this enzyme represents an ideal target for the development of novel antibacterial/antimicrobial agents.
BIOL 496, Research
Colin Willis & Paul Allee
Bucher Room, 10 AM – Noon
W100, 1:30 – 2 PM