Development of Microemulsion Containing Alpinia galanga Oil and Its Major Compounds: Enhancement of Antimicrobial Activities

Abstract

The aim of the present study was to develop a microemulsion (ME) containing Alpinia galanga oil (AGO), 1,8-cineole (C), or methyl eugenol (M) as an active pharmaceutical ingredient (API) for enhancing their antimicrobial activities. Agar diffusion, broth microdilution, and killing kinetics were used for antimicrobial evaluations. The ME composed of 30% API, 33.4% Tween 80, 16.6% ethanol, and 20% water appeared as translucent systems with droplet size and polydispersity index of 101.1 ± 1.3 nm and 0.3 ± 0.1, 80.9 ± 1.1 nm and 0.4 ± 0.1, and 96.6 ± 2.0 nm and 0.2 ± 0.1 for ME-AGO, ME-C, and ME-M, respectively. These ME formulations showed minimum bacterial concentrations of 3.91–31.25 µg/mL and 50% fungal inhibition concentrations of 1.83 ± 0.27–0.46 ± 0.13 µg/mL, 2–4 times stronger, and faster kinetic killing rate than their respective API alone. Keeping the ME formulations at 4 C, 25 C, and 40 C for 12 weeks did not affect their activities against fungi and Gram-negative bacteria, but the high temperature of 40 C decreased their activities against Gram-positive bacteria. It is concluded that ME is a promising delivery system for AGO and its major compounds to enhance their water miscibility and antimicrobial activities.

Development of Antimicrobial Edible Film Enriched with Double Emulsion of Cinnamon (Cinnamomum burmannii) Essential Oil

“…The yield (% w/w) of cinnamon essential oil obtained through the distillation process was 0.79±0.05% which was higher than several other research 0.45-0.86% (Khumpirapang et al, 2021;Lixandru et al, 2010;Tarek et al, 2014). The difference in yield of the cinnamon essential oil was due to some factors, one of them being the distillation condition which includes pressure, temperature, and contact time.…”

A review of the antimicrobial activity of thermodynamically stable microemulsions

“…Microemulsions have also been used as antiviral therapeutics and delivery systems (Franklyne et al 2021). The enhancement of the natural antimicrobial activity of the Asian ginger spice, galangal (Alpinia galanga) has been achieved by microencapsulation in a microemulsion system as shown by Khumpirapang et al (2021). In addition, the antimicrobial activity of essential oils has been enhanced through their entrapment within microemulsions (Almasi et al 2021b;Thakur et al 2021).…”

Natural product‐based nanomedicine applied to fungal infection treatment: A review of the last 4 years

“…Khumpirapang et al (2021) evaluated the antimicrobial activity of ME composed of Tween 80, ethanol, Alpinia galanga oil, 1,8‐cineole or methyl eugenol used as one compartment, surfactant mixture (Smix), and water. The IC 50 of A .…”