Optimization of Pressurized Liquid Extraction of Essential Oil from Citrus Sinesis Peels.

Abstract

Optimization of extraction of essential oil from Citrus sinesis (sweet orange) peels by Pressurized Liquid Extraction (PLE) was performed using response surface methodology (RSM). In order to obtain the maximum yield of essential oil, a two-factor Central Composite Design (CCD) experiments were conducted using extraction variables; temperature 46 - 70 ^ᵒC and static extraction cycles time 30 - 60 min. Subsequently the total phenolic content and antioxidant property using DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) of essential oil was evaluated. The Response Surface analysis gave 70 ^°C and 60 min static extraction cycle time as the optimal condition to achieve the maximum yield of essential oil, while moderate yield was at 46 ^ᵒ C and 45 min of static extraction cycles. The extraction yield and antioxidant property using ABTS radical scavenging abilityunder the above conditions were 49.3 and 22.1%; and 11.56 and 11.53 mg trolox/g. The low temperature of moderate yield was preferred which may prevent loss of some thermosensitive compounds in the essential oil.