Phytochemical Analysis of Polyphenols in Leaf Extract from Vernonia amygdalina Delile Plant Growing in Uganda

Łukasz Kuźma,Anna K Kiss,Esther Katuura,Jadwiga Nowak,Charles Wambebe

doi:10.3390/app12020912

Abstract

Due to the presence of phytochemicals, plants have been known to be used in the treatment and management of various diseases. Vernonia amygdalina, belonging to the Asteraceae family, is a plant known for its many applications in traditional medicine for various purposes. Previous studies on the methanolic leaf extract of this plant have proved the antibacterial, cytotoxic, anticancer and antioxidant effects indicative of promising therapeutic potentials. In this work, chromatographic and spectroscopic techniques along with high-performance liquid chromatography quantitative analysis were adopted to isolate, identify and quantify polyphenolic compounds in V. amygdalina leaf extract. UHPLC-DAD-ESI-MS/MS and UHPLC-DAD methods were adopted for qualitative and quantitative analysis, respectively. In the case of polyphenol separation, some reference substances were isolated by preparative HPLC. Seven polyphenols were identified and quantified in this study: 5-O-caffeoylquinic acid, luteolin hexoside, 3,4-O-dicaffeoylquinic acid, 1,5-O-dicaffeoylquinic acid, 3,5-O-dicaffeoylquinic acid, 4,5-O-dicaffeoylquinic acid and luteolin dihexoside, with 3,5-O-dicaffeoylquinic acid being isolated in the highest quantity of 27.49 mg g−1 extract.

Highlights

Medicinal plants have been used to prevent and treat various health problems for many ages [1,2,3], and despite the great advancement in modern medicine, phytotherapy is still commonly used [3]
The body’s immune system ability to recognize and destroy cancer cells is enhanced by phenolics, and they appear to increase the efficacy of standard chemo- and radiotherapeutic regimens and avert resistance to these agents [8,9]
Colorimetric MTT assay measuring cell metabolic activity found that V. amygdalina leaf extract inhibits the proliferation and induces apoptosis of MCF-7 and MDAMB-231 human breast cancer cell lines in a time- and dose-dependent manner through both extrinsic and intrinsic pathways [12]

Summary

Introduction

Medicinal plants have been used to prevent and treat various health problems for many ages [1,2,3], and despite the great advancement in modern medicine, phytotherapy is still commonly used [3]. Various phytochemicals produced by plants may vary both qualitatively and quantitatively according to many factors such as weather, ecology, time and age of collection [4] Their active components, including phytosterols, essential oils and phenolics, have been investigated as potential therapeutic agents and towards isolation of novel compounds that can be later structurally modified for therapeutic purposes [5]. Both monophenolic and polyphenolic components from a large number of plants have been proven to delay or lessen the initiation, progression and spread of cancers in both in vitro and in vivo studies [6]. The same plant exhibited compatibility with doxorubicin, indicating that it can complement current chemotherapy [12]

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Discussion

Conclusion