Location: Natural Products Utilization ResearchTitle: Chemical composition and bioactivity studies of Alpinia nigra essential oils Author
|Rehman, Junaid Ur|
Submitted to: Industrial Crops and Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/16/2013
Publication Date: 2/5/2014
Citation: Ghosh, S., Ozek, T., Tabana, N., Aabas, A., Rehman, J., Khan, I.A., Rangan, L. 2014. Chemical composition and bioactivity studies of Alpinia nigra essential oils. Industrial Crops and Products. 53:111-119. Interpretive Summary: Alpinia nigra is reported for its uses as a vegetable diet and also most popular uses as food flavoring agents by tribal people from different parts of North East India. In the presenta study, seeds, flowers, leaves and rhizomes of A. nigra essential oils was conducted to investigate the effectiveness of against the food borne and other pathogenic bacteria and further explored these oils for larvicidal and biting deterrent activity against Aedes aegypti L. All the essential oils showed strong free radical scavenging activity and oils also showed bactericidal effect against human pathogens. The seed essential oil was found most effective in biting deterrent activity than other oils against female Ae. aegypti and only flower essential oil showed larvicidal activity 1 day old Ae. aegypti larvae.
Technical Abstract: Free radical scavenging, bactericidal and bitting deterrent properties of Alpinia nigra essential oils (EOs) were investigated in the present study. Chemical composition of the EOs were analyzed using GC-MS/GC-FID which revealed the presence of 63 constituents including ß-caryophyllene as major component. All the EOs were found to possess notable antioxidant activities as determined using methods for scavenging of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical. Rhizome essential oil (REO) exhibited best effective free radical scavenging activities among other EOs compared to the standard antioxidant, butylated hydroxyl toluene. The efficacy of A. nigra EOs were tested against three gram positive and four gram negative bacteria. Flow cytometry, field emission scanning electron microscopy and transmission electron microscopy studies revealed the bacterial cell membrane damage and disintegration when they are treated with REO. Further, all EOs showed weak biting deterrent and larvicidal activity against the blood-feeding female adults and 1 day old Ae. aegypti larvae except flower essential oil which was inactive at 125 ppm. Current investigation highlights the deatiled chemical composition and bioactive potential of A. nigra EOs for the first time.