Enzyme‐assisted extraction of essential oils from Syzygium aromaticum

Abstract

The essential oil of clove ( Syzygium aromaticum) holds an important positionamongst widely used essential oils. A typical steam distillation processfor the extraction of clove oil provides a 10.1% yield. Recent studies involvedthe use of enzymes such as pectinase, amylase, lignocellulase, and cellulaseon the powder of clove buds, prior to extraction. The traditional methods ofphysical and chemical extraction are effective but may affect the structure,quality and yield of the phytochemicals extracted. In the current study,hence, enzymes specific for action on the cell wall have been used in the pretreatment prior to extraction, to enhance the quality and yield of the phytochemicalsextracted. The results indicated that all the enzymes, gave morethan 50% higher yield than control in terms of weight of extracted essentialoil. A mixture of the enzymes gave the highest yield of 17.82%. Gas chromatographyresults indicated that the essential oil extracted using amylase hada maximum eugenol content of 70%, in comparison with the eugenol content(62–68%) in the essential oils extracted using the rest of the enzymes.Antibacterial activity of all the extracts was studied on methicillin â€resistantStaphylococcus aureus  (MRSA). The essential oil extracted by using amylaseinhibitedMRSA, showed a zone size of 40 mm, whereas the essential oil extractedby using lignocellulase showed a zone size of 45 mm. The gas chromatogramindicated the maximum number of peaks in this extract, whichcould be producing a combined antibacterial effect on the organism. Thespecific gravity values of the essential oil extracted using lignocellulase andamylase was 1.051 and 1.062, respectively, whereas the control had a specificgravity of 1.015.