Physicochemical Profiling and Nanoencapsulation of Essential Oil Extracted from Acid Lime (Citrus aurantifolia) Peel Powder

Abstract

Objective: Extraction and characterization of essential oil from acid lime (Citrus aurantifolia) peel powder using green technology and nanoencapsulation of the extract in polyethylene glycol 4000 (PEG 4000). Methodology: The Citrus aurantifolia peels were dried using two different methods, solar drying and tray drying, and optimization was carried out based on the phytochemical composition. The optimized powder was subjected to hydro-distillation and its chemical composition was analyzed by FTIR. The lime peel essential oil was subjected to nanoencapsulation by the melt dispersion technique, by encapsulating the essential oil in molten PEG 4000. The mixture is subsequently cooled to 4°C and pulverized in a chilled mortar to obtain nanoparticles. The antimicrobial activity of nanoparticles against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa was tested. Results and Conclusions: Among the powder samples, the tray-dried sample at 50℃ displayed higher total phenolic, total flavonoid, radical scavenging activity, and ascorbic acid content of 73.41±0.15 mg GAE/g, 45.52±0.21 mg QE/g, 84.91±0.09 %, and 136.54±0.27 mg/100g, respectively. An essential oil yield of 1.3% v/v and an encapsulation efficiency of 51.1±1.19% were obtained from this sample. Moreover, the lime essential oil nanoparticles showed potential antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, with zone of inhibition of 11.1mm, 10.3mm, and 14.4mm, respectively. Therefore, the essential oil nanoparticles are a potential source for developing natural preservatives, functional foods, and nutraceutical formulations.