Comparative Determination of Total Phenolic Content and Flavonoid Content of Hanopol (Poikilospermum suaveolens) Using Water and Aqueous Ethanol as Extracting Solvents

Abstract

Phenolic compounds which are ubiquitous in plants have been shown to exhibit
antioxidant activity. Consequently, these compounds may reduce the risk of
degenerative diseases including certain types of cancer and heart diseases. Since the
phenolic contents of Hanopol (Poikilospermum suaveolens) have not been widely
explored, this study was conducted to compare to the total phenolic content (TPC)
and total flavonoid content (TFC) of water and aqueous ethanol crude extracts of the
dried leaves and vines of Hanopol using Folin-Ciocalteau and Aluminum chloride
colorimetric assays, respectively. The leaves and vines extracted with aqueous
ethanol as solvent showed TPC values of 485.4 and 148.0 mg gallic acid equivalent,
respectively, higher than extracted with water only with 63.9 mg and 56.2 mg gallic
acid equivalent, respectively. Total flavonoid content in the leaves and vines
extracted with aqueous ethanol were 152.3 and 24.9 mg catechin equivalent,
respectively while leaves and vines extracted with water only showed significantly
lower TFC (p <0.001, Tukey’s post-hoc test). Results of this study showed that the
enhanced polarity of aqueous ethanol exhibited better extracting capacity than water
only towards phenolic compounds. The use of liquid chromatographic technique to
separate individual phenolics compounds and identification of molecular structure
using mass spectrometry are warranted for future studies.