Curcuma longa L.: drying and biological potentials

This study evaluated the drying of curcuma longa L. rhizomes by applying mathematical modeling, determined antimicrobial activity and essential oil (EO) toxicity obtained after the drying process applied. The collected plant material was submitted to a convective drying oven at 45 °C. Mathematical models were applied to represent the drying process and statistical analysis performed using statistic software 10. The EOs were obtained through hydrodistillation technique and antimicrobial activity by the Method of Disc Diffusion and Dilution in Broth against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella sp. For the toxicity test, the bioassay of Artemia salina was applied. Through the results obtained it was possible to determine that logarithm's mathematical model was the one that best fit the experimental data. The EO showed bactericidal activity against all microorganisms tested. The toxicity assay proved EO toxicity with a LC50 greater than 250 mg/L. The results obtained prove the potential necessary for the application of EO from the rhizomes of C. longa as antimicrobial, and are still non-toxic against non-target organisms.