PHYTOCHEMICAL SCREENING, PHENOLICS AND FLAVONOIDS QUANTIFICATION, AND FREE RADICAL SCAVENGING POTENTIAL OF EMILIA PRAETERMISSA MILNE-REDHEAD (ASTERACEAE) LEAF
Keywords:
Emilia praetermissa, Antioxidant, Total Phenolic Content, Total Flavonoid Content.Abstract
Introduction: Phytochemicals have been linked to the activities exhibited by extracts and fractions
from plant in in-vivo and in-vitro experiments. Phenols and flavonoids, two important
phytochemicals are implicated in the treatment of different illnesses. They contain at least an
aromatic ring and hydroxyl group in their molecules, which are relevant moiety in their in-vitro
quantification. Emilia praetermissa, an annual herb, use in traditional medicine for the treatment
of varieties of ailments which are oxidative stress related.
Aims: This study aims to evaluate qualitatively phytochemicals in the extract and fractions, limit
the quantitative determination of the phytochemicals to total flavonoids and phenolic contents, and
evaluate their 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity.
Methods: The methanol extract and fractions obtained from liquid-liquid partitioning of the
extract with n-hexane, dichloromethane and ethylacetate were screened for phytochemicals by
using preliminary established screening methods. While the level of flavonoids and phenolic
compounds were determined spectroscopically using 10 % aluminum chloride and 10 % Folin
Ciocalteu reagents. Antioxidant potential was evaluated by the ability of the extract and fractions
to scavenge for free radicals from DPPH.
Results: Flavonoids and phenolic compounds were identified in the extract and fractions, and
quantitatively dichloromethane fraction showed the highest level for phenols 60.94±0.22 mg
GAE/g and flavonoids 19.43±0.06 mg QE/g. Radical scavenging potential of the n-hexane fraction
compared favorably with the standard, methanol extract and dichloromethane fraction (p < 0.05),
and IC50 of 30.00 µg/mL was recorded for dichloromethane fraction.
Conclusion: This study shows that Emilia praetermissa leaf contains varying classes of
phytochemicals especially flavonoids and phenols that can scavenge for free radicals.