Study on the antibiotic activity of microcapsule curcumin against foodborne pathogens

Curcumin as an edible natural pigment has several biological activities but its use as a food colorant and preservative is restricted due to low stability and insolubility in water. Stabilizing it with microencapsulation to obtain microcapsule curcumin can improve its stability and solubility. The microcapsule curcumin was studied for their antibacterial and antifungal activities against some foodborne pathogens and spoilage microbe such as Escherichia coli. Yersinia enterocolitica, Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Aspergillus niger, Penicllium notatum, and Saccharomyces cerevisiae. It exhibited broad spectrum inhibitory effect against all organisms by Oxford cup methods, and its minimum inhibitory concentrations (MIC) were determined by agar dilution method and ranged from 15.7 to 250 mu g/mL For the selected microorganisms, its antibacterial activity was more pronounced against Gram-positive bacteria than Gram-negative bacteria. Furthermore, its antifungal activity is much better than antibacterial activity. Microcapsule curcumin remains in antibacterial and antifungal activities after microencapsulation, which can be potential colorant and preservative in food industry. (C) 2009 Elsevier B.V. All rights reserved.