Screening for antibiofilm and antioxidant potential of turmeric (Curcuma longa) extracts

The antibiofilm and antioxidant activities associated with turmeric were the main focus of the study. Antibacterial activity was explored against bacteria isolated from dental plaques and dental unit water lines exhibiting resistance against antibiotics and biocides respectively. This study provides a comparison of the natural plant extract against synthetic mouthwash, chemicals and commonly prescribed antibiotics. Methanol extract was more effective as compared to other extracts. Minimum inhibitory concentrations (MIC) ranged from 2.5-10mg/ml. Time based killing kinetic assay showed a significant reduction of bacterial load with increasing concentration of turmeric. Micro titer plate assay indicated significant inhibition of biofilm formation in cells treated with turmeric extract. Phytochemical screening of plant extracts showed the presence of vital secondary metabolites. Flavonoid content and total phenolic content varied among extracts, phenolic content for methanolic extract was 61.669 mg GAE/ gm dry extract and flavonoid content was 3.119mg quercitin/gm dry extract. The values of ferric reducing power were in the range of 5.55- 15.55 mmol of FeSO4 equivalent/ liter of the extract. Antioxidant activities and total phenolic content of the turmeric extracts had significant positive correlation. On the basis of these results turmeric may confidently be recommended as natural antibiofilm and antioxidant agent.