Retrieval of High Added Value Natural Bioactive Coumarins from Mandarin Juice-Making Industrial Byproduct.

Eleni D Myrtsi,Serkos A Haroutounian,Apostolis Angelis,Sofia Mitakou,Sofia D Koulocheri

doi:10.3390/molecules26247527

Abstract

Cold pressed essential oil (CPEO) of mandarin (Citrus reticulata Blanco), a by-product of the juice-making industrial process known to contain large amounts of polymethoxyflavones, was exploited for its content in high added value natural coumarins. The study herein afforded a method referring to the evaporation of CPEO volatile fraction under mild conditions (reduced pressure and temperature below 35 °C) as azeotrope with isopropanol. This allowed the isolation of high added value coumarins from the non-volatile fragment using preparative High Performance Liquid Chromatography (HPLC). Pilot-scale application of this procedure afforded for each kg of CPEO processed the following natural bioactive coumarins in chemically pure forms: heraclenol (38–55 mg), 8-gerayloxypsoralen (35–51 mg), auraptene (22–33 mg), and bergamottin (14–19 mg). The structures of coumarins were verified by Nuclear Magnetic Resonance (NMR) spectroscopy and HPLC co-injection with authentic standards. Thus, the low market value mandarin CPEO with current value of 17 to 22 EUR/kg can be valorized through the production of four highly bioactive natural compounds worth 3479 to 5057 EUR/kg, indicating the great potentials of this methodology in the terms of the circular economy.

Highlights

Coumarins belong to plant-derived secondary metabolites that structurally are classified into benzopyrone derivatives
Many medicinal and aromatic-edible plants belonging to widely distributed plant families, such as Rutaceae, Moraceae, Apiaceae, and Fabaceae, have been determined as plant sources for the isolation of natural coumarins [22,23,24,25]
Citrus crops are included among the richest sources of natural compounds, including coumarins and furanocoumarins [39]

Summary

Introduction

Coumarins belong to plant-derived secondary metabolites that structurally are classified into benzopyrone derivatives They are known as molecules exhibiting a broad spectrum of bioactivities, including anticancer [1], anti-HIV [2], antioxidant [3,4,5,6], anticoagulant [7], antiviral [8,9,10], antimicrobial [11,12], anti-inflammatory [13] and Central. Vigorous research activity has been initiated towards the discovery of bioactive molecules containing the coumarin structural backbone either from natural resources [18] and/or synthetic pathways [19,20,21]. A broad diversity of novel synthetic derivatives and analogs of coumarins has been prepared [13,20,26,27] providing leads for utilization in photochemotherapy, in antitumor and anti-HIV therapies, as anti-coagulant, anti-inflammatory, and anti-bacterial agents and as CNS stimulants [1,2,3,8,9,20,28,29]

Methods

Findings

Discussion

Conclusion