Abstract
Essential oils from plants have been proven safe as natural antioxidants, and few are already marketed as digestive enhancers as well as in prevention of several degenerative diseases. This study evaluated the antioxidant capacity of seed and shell essential oils of Abrus precatorius (L), a herb used for ethno-medicinal practices in Nigeria. The essential oils were obtained by hydro-distillation. The ability of the oils to act as hydrogen/electrons donor or scavenger of radicals were determined by in-vitro antioxidant assays using 2,2-diphenyl-2-picryl-hydrazyl free radical (DPPH.) scavenging; 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging; lipid peroxide and nitric oxide radicals scavenging assays. The IC50 of the seed and shell oils (2.10 mg/mL and 1.20 mg/mL respectively) showed that antioxidant activity is higher than that for the standard drugs (3.20 mg/mL and 3.40 mg/mL) for the nitric oxide scavenging assay. The lipid peroxidation radical activity of the oils were similar to vitamin C, weak DPPH and ABTS radical scavenging activities were discovered in comparison to vitamin C and rutin. Generally, in the four antioxidant assays, a significant correlation existed between concentrations of the oils and percentage inhibition of free radicals and lipid peroxidation. The composition of A. precatorius essential oils reported earlier may account for their antioxidant capacity.
Highlights
There are increasing evidences that free radicals produced molecular alterations that are associated with various degenerative human diseases such as arteriosclerosis, cancers, Alzheimer’s disease, Parkinson’s disease, diabetes, asthma, arthritis, immune deficiency diseases and aging [1,2,3,4]
In the ABTS free radical assay, the method of Witayapan [23] was adopted with minor changes (ABTS stock solution diluted in methanol)
The mixture was allowed to react for 12 h in the dark at 25 °C. 1 mL of the resulting solution was diluted in 60 mL of methanol to obtain an absorbance of 0.706 ± 0.001 at 734 nm. 1 mL of the ABTS radical cation solution was added to the 0.025, 0.05, 0.10, 0.2 and 0.5 mg/mL of essential oil solutions and commercial antioxidants prepared in methanol and absorbance measured at 734 nm
Summary
There are increasing evidences that free radicals produced molecular alterations that are associated with various degenerative human diseases such as arteriosclerosis, cancers, Alzheimer’s disease, Parkinson’s disease, diabetes, asthma, arthritis, immune deficiency diseases and aging [1,2,3,4]. Plants contain antioxidant compounds that function as free radical scavengers, reducing agents and quenchers of singlet oxygen formation [7]. There have been increasing suggestions and demand for use of essential oils as natural antioxidant than any other plant extracts as potential substitute for the synthetic ones [8,9,10]. Studies have shown that these unique properties are due to volatile, lipophilic nature and chemical structure of essential oil compounds as well as their strong potency as free radical quenching agents [11]. There is dearth of information on the antioxidant capacity, and free radical scavenging activity of the essential oil of the plant.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
