Antioxidant and antimicrobial activities of rosemary extracts linked to their polyphenol composition.
Rosmarinus officinalis extracts were investigated by a combination of bioassays and biochemical analysis to identify bioactive compounds. The 2,2-diphenyl-2-picrylhydracyl hydrate (DPPH) radical scavenging method, Folin-Ciocaulteau method and HPLC chromatography were used to study the distribution and levels of antioxidants (AOXs). Antimicrobial activity analysis was carried out using the disk diffusion and broth dilution techniques. A good correlation between the AOX activities and total phenol content in the extracts was found. Although all rosemary extracts showed a high radical scavenging activity, a different efficacy as antimicrobial agent was observed. Methanol extract containing 30% of carnosic acid, 16% of carnosol and 5% of rosmarinic acid was the most effective antimicrobial against Gram positive bacteria (minimal inhibition concentration, MIC, between 2 and 15 mug/ml), Gram negative bacteria (MIC between 2 and 60 mug/ml) and yeast (MIC of 4 mug/ml). By contrast, water extract containing only 15% of rosmarinic acid showed a narrow activity. MIC value of the methanol and water extracts is in a good correlation with the values obtained with pure carnosic acid and rosmarinic acid, respectively. Therefore, our results suggested that the antimicrobial rosemary extracts efficacy was associated with their specific phenolic composition. Carnosic acid and rosmarinic acid may be the main bioactive antimicrobial compounds present in rosemary extracts. From a practical point of view, rosemary extract may be a good candidate for functional foods as well as for pharmaceutical plant-based products.
Moreno
Silvia
S
Instituto de Investigaciones Bioquímicas, Buenos Aires I.I.B.B.A.-CONICET, Universidad de Buenos Aires, Fundación Instituto Leloir, Facultad de Ciencias Exactas y Naturales, Patricias Argentinas 435, Buenos Aires, 1405, Argentina. smoreno@leloir.org.ar
Scheyer
Tamara
T
Romano
Catalina S
CS
Vojnov
Adrián A
AA
D045784:Abietanes / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D001713:Biphenyl Compounds; D002851:Chromatography, High Pressure Liquid; D002934:Cinnamates / Q000494:pharmacology; D053630:Depsides; D005419:Flavonoids / Q000494:pharmacology*; D005609:Free Radicals; D007202:Indicators and Reagents; D010616:Phenanthrenes / Q000494:pharmacology; D010636:Phenols / Q000494:pharmacology*; D010851:Picrates; D010936:Plant Extracts / Q000494:pharmacology*; D059808:Polyphenols; D027542:Rosmarinus / Q000737:chemistry*; D012441:Saccharomyces cerevisiae / Q000187:drug effects; D000097123:Rosmarinic Acid
D045784:Abietanes; D000890:Anti-Infective Agents; D000975:Antioxidants; D001713:Biphenyl Compounds; D002934:Cinnamates; D053630:Depsides; D005419:Flavonoids; D005609:Free Radicals; D007202:Indicators and Reagents; D010616:Phenanthrenes; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; D059808:Polyphenols; D000097123:Rosmarinic Acid; C068623:carnosol; C004931:1,1-diphenyl-2-picrylhydrazyl; C018381:salvin