Effect of harvesting time on phytochemical profile and antioxidant activity of essential oil from Citrus medica leaves
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Date
2017
Journal Title
Journal ISSN
Volume Title
Publisher
College of Natural Sciences, Al-Hikmah University, Ilorin
Abstract
Leaves (500 g) of Citrus medica L. harvested at interval of three hours from 7.00 am to 7.00 pm on a day during dry season were separately hydrodistilled for three hours. Oil yields from the leaves ranged from 0.22 - 0.34%. GC and GC-MS analyses revealed the predominant of monoterpenoids (50.5 - 70.3%) in theoils. The percentage composition of sesquiterpenoids was in the range of 29.7 - 29.5%. The principal constituents of the oils were; ocimene (4.1 - 5.6%), D-limonene (13.5 - 19.8%), terpinene (10.8 - 17.9%), linalool (3.8 - 4.0%), citronellal (2.7 - 7.5%), terpinen-4-ol (1.2 - 8.7%), citronelol (10.1 - 13.7%), linalyanthranilate (2.5 - 9.3%), elemene (3.0 - 6.4%), bergamotene (4.1 - 6.6%), humulene (1.2 - 2.8%), caryophyllene (7.9 - 16.5%), bisabolene (3.6 - 5.2%). The oils were of D-limonene and terpinene chemotypes. Antioxidant activity assay on the oils revealed that they were biochemically active against DPPH radicals. The activity was concentration dependent with the oil from 7am harvest having the highest activity and lowest EC50. Hence, the plant may be used as an alternative to synthetic antioxidants.
Description
Keywords
D-limonene, Terpinene, chemotypes, antioxidants, Citrus medica
Citation
Usman, L.A., Ologunja, S.O., Ismaeel, R.O., Akolade, J.O. & Olanipekun, B.E. (2017). Effect of harvesting time on phytochemical profile and antioxidant activity of essential oil from Citrus medica leaves