Antibacterial and antioxidant lemongrass essential oil Pickering emulsion stabilized by cellulose nanocrystals

Abstract

An effective antibacterial system was developed by using cellulose nanocrystals (CNC) to stabilize lemongrass essential oil Pickering emulsion (PE-LEO) through ultrasonication technology. The factors affecting the formation and stability of PE-LEO were studied, such as ultrasonication times, CNC concentrations, lemongrass essential oil (LEO) concentrations. By size and zeta index, the most suitable sample was 8 ultrasonication times, 0.8% CNC, 15% LEO. The antibacterial and anti-fungal performance of PE-LEO was investigated by determining the minimal inhibitory concentrations (MIC). The results showed that for gram-positive bacteria (E.faecalis, S.aureus, MRSA), the MIC of PE-LEO was much higher than LEO, the opposite was true for gram-negative bacteria (E. coli) and fungi. Based on the concentrations of LEO, with IC50 of PE-LEO is 0.30% vLEO/v, which is significantly lower than that of LEO (0.99%). The CNC-stabilized PE-LEO exhibited higher antioxidation activity at equivalent LEO concentrations. The fabricated CNC based Pickering emulsions provide a promising alternative for the delivery of antimicrobial essential oils in the food industries.