title: Evaluation of antioxidant activity of vetiver (Vetiveria zizanioides L.) oil and identification of its antioxidant constituents.
abstract: Antioxidant capacities of vetiver (Vetiveria zizanioides) oil were evaluated by two different in vitro assays: the DPPH* free radical scavenging assay and the Fe2+-metal chelating assay. Results showed that the vetiver oil (VO) possessed a strong free radical scavenging activity when compared to standard antioxidants such as butylated hydroxytoluene (BHT) and alpha-tocopherol. However, its metal chelating capacity was relatively weak. VO (10 microL/mL) dissolved in methanol exhibited approximately 93% free radical scavenging activity in the DPPH* assay and approximately 34% Fe2+ chelating activity in the metal chelating assay. By contrast, 10 mM BHT and 0.1 mM alpha-tocopherol exhibited 93 and 89% free radical scavenging activities in the DPPH* assay, respectively, and 1 mM EDTA exhibited approximately 97% activity in the metal chelating assay. Among the complex constituents in the crude VO, beta-vetivenene, beta-vetivone, and alpha-vetivone, which had shown strong antioxidant activities, were isolated and identified using various chromatographic techniques including silica gel open column chromatography, silica HPLC, and GC-MS. These results show that VO and some of its inherent components can be potential alternative natural antioxidants.
authors.affiliation: Department of Food Science and Human Nutrition, Clemson University, Clemson, South Carolina 29634, USA.
authors.forename: Hyun-Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.forename: Xi
authors.initials: X
authors.lastname: Wang
authors.forename: Hau Yin
authors.initials: HY
authors.lastname: Chung
authors.forename: Zhengyu
authors.initials: Z
authors.lastname: Jin
mesh_terms: D000975:Antioxidants / Q000032:analysis* / Q000302:isolation & purification / Q000494:pharmacology; D001713:Biphenyl Compounds; D002084:Butylated Hydroxytoluene / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D005296:Ferrous Compounds / Q000737:chemistry; D016166:Free Radical Scavengers / Q000494:pharmacology; D007502:Iron Chelating Agents / Q000737:chemistry; D010851:Picrates; D010938:Plant Oils / Q000737:chemistry*; D006109:Poaceae / Q000737:chemistry*; D024502:alpha-Tocopherol / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D005296:Ferrous Compounds; D016166:Free Radical Scavengers; D007502:Iron Chelating Agents; D010851:Picrates; D010938:Plant Oils; D002084:Butylated Hydroxytoluene; D004492:Edetic Acid; C004931:1,1-diphenyl-2-picrylhydrazyl; D024502:alpha-Tocopherol