Antioxidant Activity Influenced by Seasonal Variation of Essential Oil Constituents of <i>Ocimum gratissimum</i> L.
Rajesh K. Joshi
Abstract
In traditional medicine, the plant Ocimum gratissimum L. (Lamiaceae) is employed in neurological specialty and rheumatic affections, in seminal weakness, and aphthae of children. In homeopathy, the recent mature leaves are employed in constipation, cough, fever, nasal catarrh, and additionally in gonorrhea with troublesome urination. The essential oil is obtained by a Clevenger sort equipment from leaves of Ocimum gratissimum L. (Lamiaceae) acquired during one year. The chemical composition of the essential oil is examined by exploitation of gas chromatography fitted with a flame ionization detector (GC-FID) and gas chromatography connected with mass spectrometry (GC–MS). The antioxidant activity of oils and eugenol was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH·) colored persistent radical assay. The yield variation of oil was found to be within the purview of 0.17 to 1.07% (w/w). Thirty-four to 42 known constituents were delineated as 97.27 ± 0.27% of the entire oil. Eugenol was an associated significant compound in inconsistent amounts ranging from 65.65 ± 0.57 to 85.71 ± 0.55%, in accord with modest variations among different constituents. It was ascertained that no rain throughout January and February led to the monoterpene organic compound (Z)-β-ocimene being a rarity in high amounts and eugenol having low amounts. Essential oils of O. gratissimum collected throughout the study year showed antioxidant activity with IC50 values within the purview of 2.04 ± 0.04 to 3.02 ± 0.03 μg/mL. The essential oil gathered in June showed higher antioxidant activity with an IC50 value of 2.04 ± 0.04 μg/mL, and that gathered in February showed the lowest IC50 value of 3.02 ± 0.03 μg/mL. The months March to November were favorable for the synthesis of a high quantity of medicinally vital eugenol by O. gratissimum within the range of 81.71 ± 0.34 to 85.71 ± 0.55% with antioxidant activity less than 3.0 μg/mL.