Supercritical fluid extraction of Citronella oil from Cymbopogon nardus and its optimization

Citronella essential oil from leaves of Cymbopogon nardus has received much attention nowadays due to its special properties for pharmaceuticals, cosmetics and perfumery applications. To the best of our knowledge, reported work on extraction of Citronella oil using advance technique is very limited. In this study, the oil was extracted using supercritical fluid extraction (SFE) at temperature range 40 to 80°C and pressure o from 100 to 250 bar. The SFE condition was optimized by using response surface methodologies (RSM) while the major compounds of Citronella oil was determine using gas chromatography-mass spectrometry (GC-MS). Result showed that oil yield was increased with increasing the pressure and decreasing the temperature. The highest oil yield (2.785%) was obtained at 200 bar and 40°C whereas the highest composition of Citronellal compound (11.537%) was at 250 bar at the same temperature. The optimum extraction parameter estimated from RSM was 241 bar and 41°C, where 1.674% of oil yielded. An oil yield obtained from Soxhlet was four times higher (11.774 %) than SFE. However, still, the SFE is considered more effective method due to its clean and green properties and capability to produce high purity of oil compare to the conventional method which has retain a residue of organic solvent.