Anti-oxidant studies and anti-microbial effect of Origanum vulgare Linn in combination with standard antibiotics

BACKGROUND: Origanum is one of the over 200 genera in the Lamiaceae (mint family), and this genus includes culinary, fragrant, and medicinal properties. The plant is reported to contain anti-microbial properties, but it lacks combination studies with that of synthetic antibiotics. AIM: To investigate the anti-oxidant and anti-microbial interaction studies of Origanum vulgare with standard drugs against Bacillus species of bacteria and Aspergillus niger. MATERIALS AND METHODS: The anti-oxidant properties of phenolic, non-phenolic fractions of chloroform extract and volatile oil were evaluated by free radical-scavenging, hydrogen peroxide radical-scavenging assay, reducing power, and metal chelating assays. RESULTS: The minimum inhibitory concentration and fractional inhibitory concentration index were determined which demonstrates the behavior of volatile oil, phenolic, and non-phenolic fractions of volatile oil with that of ciprofloxacin and fluconazole. The IC(50) value for volatile oil was found to be 15, 30, and 30 μg/ml and that of phenolic fraction was 60, 120, and 120 μg/ml for free radical-scavenging, hydrogen peroxide-scavenging, and metal chelating assays respectively. Non-phenolic fraction was found to act antagonistically along with ciprofloxacin against B. cereus and B. subtilis, while the phenolic fraction exhibited indifferent activity along with ciprofloxacin against both the bacterial strains. CONCLUSION: This combination of drug therapy will not only prove effective in antibiotic resistance, but these natural constituents will also help in preventing body from harmful radicals which lead to fatal diseases.