Antioxidant activity of an anatolian herbal tea—Origanum minutiflorum: isolation and characterization of its secondary metabolites

Mahfuz Elmastas,Süleyman Muhammed Celik,Nusret Genc,Hüseyin Aksit,Ramazan Erenler,İlhami Gulcin

doi:10.1080/10942912.2017.1416399

Abstract

ABSTRACTOriganum species are significant aromatic and medicinal plants used in food and pharmaceutical industries. Isolation of bioactive compounds was executed on n-butanol extract to yield the compounds responsible for the activities. Tricosan-1-ol (1), (8E,16E)-tetracosa-8,16-diene-1,24-diol (2), azepan-2-one (3), 3,4-dihydroxybenzoic acid (4), apigenin (5), eriodictyol (6), globoidnan-A (7), luteolin (8), rosmarinic acid (9), apigenin-7-O-glucuronide (10), and vicenin-2 (11) were isolated by chromatographic methods (column chromatography and semi-preparative High Performance Liquid Chromatography (HPLC) and structures were elucidated on the basis of spectroscopic techniques including 1D/2D nuclear magnetic resonance (NMR) and Liquid chromatography/Time-of-flight/Mass spectrometry (LC-TOF/MS). The isolated compounds and extracts were applied for antioxidant assays including 1,1-diphenyl-2-picrylhydrazyl (DPPH•) scavenging, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS•+) scavenging, reducing power, and cuprac techniques. 3,4-Dihydroxy benzoic acid (4), eriodictyol (6), luteolin (8), and rosmarinic acid (9) revealed the considerable antioxidant activities.

Highlights

Oxygen is the final electron acceptor in the electron flow system that produces energy in the form of adenosine triphosphate (ATP) lipid peroxidation and thereby stabilizing fat-containing food-stuffs.[1,2]. It constitutes most of the mass of living organisms, because water is their major constituent. It is very important for the continuity of vital functions and has unpaired two electrons and tends to form oxygencentered free radicals, known as reactive oxygen species (ROS).[3,4]
The oxidative deterioration of fats and oils in foods is responsible for rancid odors and flavors, with a consequent decrease in nutritional quality and safety caused by the formation of secondary, potentially toxic compounds.[8,9]
Antioxidants have been widely used as food additives to protect food quality mainly by the prevention of oxidative deterioration of lipid constituents

Summary

Introduction

Oxygen is the final electron acceptor in the electron flow system that produces energy in the form of adenosine triphosphate (ATP) lipid peroxidation and thereby stabilizing fat-containing food-stuffs.[1,2] It constitutes most of the mass of living organisms, because water is their major constituent. This genus has gained the great importance in pharmaceutical and medicinal industries due to their high amount of essential oil concentration as well as including bioactive secondary metabolites.[30] Origanum species exhibit high antioxidant activities; they can be potentially replaced with existing synthetic antioxidant.[31] Some species of these plants are well known in Anatolian folk medicine and widely used as spices and herbal tea.[32] The effectiveness is attributed to the specific composition of essential oils,[33] flavonoids,[34] phenolic acids,[35] and other chemical constituents of Origanum. Antioxidant activities of isolated compounds were investigated.

Results

Conclusion