Comparative in-vitro biological activities of methyl eugenol rich Cymbopogon khasianus Hack., leaf essential oil with pure methyl eugenol compound.

BACKGROUND: A methyl eugenol rich essential oil of Cymbopogon khasianus Hack has been evaluated and compared its bioactivities with pure methyl eugenol. So far, the methyl eugenol rich essential oil of lemon grass was not studied for any biological activities, hence the present study was proposed.
OBJECTIVE: This study examined the chemical composition of Cymbopogon khasianus Hack., methyl eugenol rich essential oil and evaluated its antioxidant, anti-inflammatory, antimicrobial, herbicidal and genotoxicity of the essential oil which was compared with pure methyl eugenol compound.
MATERIAL AND METHODS: Methyl eugenol rich essential oil a variety of Cymbopogon khasianus Hack., with registration no. INGR18037 (c.v. Jor Lab L-9), collected from experimental farm CSIR-NEIST, Jorhat Assam (26.7378° N, 94.1570° E).The essential oil was obtained by hydro-distillation using Clevenger apparatus. Chemical composition of the essential oil was evaluated using GC/MS analysis. Essential oil sample was analyzed and compared its antioxidant (DPPH assay, reducing power assay), anti-inflammatory (Egg albumin denaturation assay), antimicrobial (Disc diffusion assay, MIC), genotoxicity (Allium cepa assay), and effect on seed germinations (seed germination effect) with pure methyl eugenol compound (ME) taken as a standard.
RESULTS: Major components detected in essential oil (EO) through Gas chromatography/mass spectroscopy analysis were methyl eugenol 73.17%, and β-myrcene 8.58%. A total of 35 components were detected with a total identified area percentage of 98.34%. DPPH, assay revealed considerable antioxidant activity of methyl eugenol rich lemon grass essential oil, IC50 = 2.263 µg/mL, which is lower than the standards, ascorbic acid IC50 2.58 µg/mL, and higher than standard methyl eugenol (ME) IC50 2.253 µg/mL. Methyl eugenol rich lemongrass EO possesses IC50 38.00 µg/mL, ME 36.44 µg/mL, and sodium diclofenac 22.76 µg/mL, in in-vitro anti-inflammatory test. Moderate genotoxicity in Allium cepa assay and antimicrobial activity towards the 8 tested microbes was shown by methyl eugenol rich lemon grass essential oil whose effectiveness against the microbes are less effective as compared to pure ME standard. Seed germination assay further revealed the herbicidal properties of methyl eugenol rich essential oil.
CONCLUSION: This paper provides GC/MS analysis, antioxidant, anti-inflammatory, antimicrobial, genotoxicity and herbicidal activities of methyl eugenol rich lemon grass which can be used as alternative of methyl eugenol pure compound. Hence this methyl eugenol rich variety of essential oil has the potential of developing cost effective, easily available antioxidative/antimicrobial drugs but uses of it should be under safety range of methyl eugenol and needs further more deep analysis in this aspect. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.