Oregano and lavender essential oils as antioxidant and antimicrobialadditives of biogenic gelatin films

MARTUCCI JF; GENDE LB; NEIRA LM; RUSECKAITE R

Industrial Crops and Products

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2015 vol. 71 p. 205 - 213

0926-6690

tThe chemical composition of the essential oils obtained by hydrodistillation from fully-formed, driedoregano leaves (Origanum vulgareOriganum vulgare) and lavender leaves and flowers (Lavandula offic-inalis) were analyzed by GC/MS. The effectiveness of oregano (OEO) and lavender (LEO) essentialoils and a mixture LEO:OEO (50:50) in inhibiting Escherichia coli and Staphylococcus aureus growthwere determined. Both essential oils inhibited the growth of the microorganisms tested, being moresensitive to gram-positive bacteria. OEO yielded the lowest values of minimum inhibitory con-centration (MICOEO= 1600?1800 ppm vs. MICLEO= 2000 ppm against E. coli; MICOEO= 800?900 ppm vs.MICLEO= 1000?1200 ppm against S. aureus), due to the higher content of phenolic compound, which alsoprovides antioxidant capacity (IC50OEO= 297 ± 89 ppm vs. IC50LEO» 6000 ppm). Mixture results indicatedan antagonist antimicrobial effect between OEO and LEO. Gelatin-based films added with OEO or LEO,were prepared by casting (2000?6000 ppm). Mechanical, optical and water vapor barrier properties weredetermined to observe film functionality. OEO effect on the functional properties of gelatin films was notsignificant. LEO, in the highest concentration analyzed, promotes a slight change in water vapor perme-ability of Ge-based films (1.46 × 10−13to 6.8 × 10−14Kg.m/Pa.s.m2), due to its high hydrophobic nature.Oregano containing gelatin films exhibited the highest antimicrobial and antioxidant properties.