Evaluation of Natural Plant Powders with Potential Use in Antimicrobial Packaging Applications.

摘要

This study investigates the antimicrobial effects of vanillin, turmeric and curcumin in packaging coating application. Reagent alcohol and DMSO were introduced as two solutions for the three antimicrobial agents. The coating solutions involving these three antimicrobial agents are: vanillin/ Reagent alcohol (10, 5, 2.5 and 1.25% (w/w)), vanillin/DMSO (10, 5, 2.5, 1.25, 0.625 and 0.3125% (w/w)), turmeric/ Reagent alcohol (10, 5, 2.5 and 1.25% (w/w)), turmeric/DMSO (10, 5, 2.5, 1.25, 0.625 and 0.3125% (w/w)), curcumin/ Reagent alcohol (10, 5, 2.5 and 1.25 (w/w)) and curcumin/DMSO (10, 5, 2.5, 1.25, 0.625 and 0.3125% (w/w)). The antimicrobial activity effects of the aforementioned coating solutions were investigated for five types of common pathogens and food spoilage bacteria: Staphylococcus aureus and Listeria monocytogenes representing gram-positive bacteria; Shigella sonnei, Salmonella typhimurium as well as E.coli O157:H7 representing gram- negative bacteria. Significant antimicrobial effects for gram-positive bacteria were observed for curcumin and turmeric in their Reagent alcohol and DMSO solutions. It is also noticed that E.coli O157:H7 was more sensitive over vanillin/ Reagent alcohol solution, however, Listeria monocytogenes was more sensitive over vanillin/ DMSO solutions. The factors that influence the solution's antimicrobial activity were studied. Turmeric is chosen as the antimicrobial agent to be incorporated into polymers. In order to study the antimicrobial effect as packaging application, two types of the polymer based turmeric products were evaluated. They are LDPE based turmeric pellets produced by a single screw extruder, and turmeric coated BOPP films.