minimum inhibitory concentration

Polyphenol oxidase(PPO) is a food enzyme which holds a very important place in the food industry mainly because of its impairing effects. This enzyme leads to the darkening of tissue when fruits are cut or any damage occurs which leads to the depreciation of nutritional value and food acceptability. It is not clear which roles this compound may have in cell metabolism. In plants, PPO contributes to defence mechanisms against pests and pathogens by producing toxic quinones that deter herbivory and inhibit microbial growth. In this report, the possible antifungal effects were examined. Analyses are carried out by properties of standard polyphenolic substances oxidized by PPO were assayed on Red delicious apple extract whose phenolics were previously isolated.

Curcuma longa is a widely used plant in folk medicine. In this study, we assessed the action of the ethanolic extract of C. longa on WHO strains of Salmonella enterica serotype Typhi and Salmonella enterica serotype Enteritidis. Curcumin is one of the most active ingredients of C. longa. In the presence of the ethanolic extract of C. longa, the bacterial count of both Salmonella was remarkably increased which was statistically highly significant. We also could not demonstrate MIC value even at 50 mg/ml concentration of the extract in Salmonella enterica serotype Typhi, while Salmonella enterica serotype Enteritidis only showed MIC value at a very high concentration of 6.25 mg/ml. However, two common bacteria E. coli and Staphylococcus aureus showed a MIC value of 0.39 and 3.125 mg/ml respectively. Thus, the use of C. longa in materials for public use should be done cautiously.