Comparative Study of Microwave-assisted Extraction and Hydro-distillation Methods for Extracting Essential Oil from Melaleuca cajuputi in Southern Vietnam: Yield, Composition, and Efficiency Analysis

Abstract

Aims: This study aimed to the extraction of Melaleuca cajuputi essential oils by microwave-assisted extraction method. The comparison for productivity of microwave-assisted extraction method and traditional hydro-distillation method was also established to figure out the optimum condition for the isolation process.
 Methodology: Microwave-assisted extraction method was employed for the isolation of Melaleuca cajuputi essential oils. The components contained in Melaleuca cajuputi essential oils were analyzed by gas chromatography-mass spectrometry. Standard methods were applied to investigate the characteristics of extracted essential oils, including density, acid index, saponification index and ester index.
 Results: The major components in the product included caryophyllene (21.45%), γ-terpinene (6.14%), α-terpinolen (7.12%), 1R-α-pinene (3%), α-caryophyllene (10.75%), α-terpineol (0.64%), 4-terpinenol (1.34%), eucalyptol (0.86%) and α-terpinen (0.77%). The highest yield of 0.42% (w/w) was obtained at optimum condition, which was water to raw material ratio of 3.5 mL/g, and extraction time of 210 minutes.
 Conclusion: The comparison of extraction process performed by microwave-assisted extraction and traditional hydro-distillation method proved that microwave-assisted extraction was effective for essential oil extraction in both quality and quantity.