Open Access Review Article
Raja et al., Pharm Anal Acta 2015, 6:5
DOI: 10.4172/2153-2435.1000367
Volume 6 • Issue 5 • 1000367
Pharm Anal Acta
ISSN: 2153-2435 PAA, an open access journal
*Corresponding author: Santanu Kar Mahapatra, Assistant Professor Research,
Medicinal Chemistry and Immunology Lab, ASK-II,Department of Biotechnology,
School of Chemical and Biotechnology, SASTRA University, Thanjavur–613401,
Tamilnadu, India, Tel: +91–4362–264101; E-mail: santanu@scbt.sastra.edu
Received April 15, 2015; Accepted April 29, 2015; Published May 06, 2015
Citation: Raja MRC, Srinivasan V, Selvaraj S, Mahapatra SK (2015) Versatile
and Synergistic Potential of Eugenol: A Review. Pharm Anal Acta 6: 367.
doi:10.4172/21532435.1000367
Copyright: © 2015 Raja MRC, et al. This is an open-access article distributed
under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the
original author and source are credited.
Abstract
Eugenol (1-allyl-4-hydroxy-3-methoxybenzene) is the phenolic component of essential oil and the main
constituent of Eugenia caryophyllata, Ocimmum gratissimum and several others medicinal plant. In view of its non-
mutagenic and non-carcinogenic properties, eugenol is generally regarded as safe by the Food and Agricultural
Organization of the United Nations. Eugenol has been recently shown to be effective for antimicrobials and treatment
of different life threatening diseases including sepsis, leishmaniasis, and cancer. However overall, activity of eugenol
is not discussed elsewhere. In this review, we discuss the current understanding of the mechanisms involved the
antioxidant, antimicrobial, anticancer and anti-infammatory potential of eugenol.
Versatile and Synergistic Potential of Eugenol: A Review
Mamilla R Charan Raja, Varsha Srinivasan, Sharmila Selvaraj and Santanu Kar Mahapatra*
Medicinal Chemistry and Immunology Lab, ASK-II, School of Chemical and Biotechnology, SASTRA University, Thanjavur 613401, Tamil Nadu, India
Keywords: Eugenol; Antioxidant; Antimicrobials; Anticancer; Anti-
infammatory potential
Introduction
Eugenol, a phenolic photochemical extracted from certain
essential oils especially from clove oil, nutmeg, cinnamon, basil and
bay leaf; possess a range of antimicrobials to anticancer activity. As it
is extracted from the buds and leaves of Eugenia caryophyllata (clove)
for the frst time mainly, it’s named as eugenol. Now a day, eugenol
can also be synthesized in laboratory scale and industrial scale by
allylation of guaiacol with allyl chloride having the similar kind of
functional property [1]. Being a major component in the extracts of
various medicinal herbs it got much attention by the researchers and
opened up a wide area of research in applying it as a medicine to cure
various diseases. Eugenol is known to have several pharmacological
properties i.e, anaesthetic, antioxidant, antimicrobial, antihelmintic,
anti-infammatory, anticarcinogenic, antifumigant, and antirepellent
properties. It has been in use as a traditional remedy for toothache and
also for culinary purposes. Tis versatile molecule is a key ingredient in
perfumes, cosmetics, favorings agents.
Both the Food and Agriculture Organization (FAO) and World
Health Organization (WHO) have allowed an acceptable daily intake
of eugenol of 2.5 mg/kg body weight for humans [2]. Moreover, the
U.S. Food and Drug Administration (FDA) have proclaimed eugenol
as safe and it is considered non-carcinogenic and non-mutagenic. In
recent years, eugenol has fascinated the attention of researchers due
to its anti-infammatory and chemopreventive activity, as well as its
superior anti-oxidant activity [3-6]. As a result of its broad range of
pharmacological and biological activities, studies on eugenol and clove
products still remains a research priority. It is therefore of signifcant
value to rationally unite some of the most worth mentioning research
fndings related to eugenol to highlight its importance in human health
as well as to elucidate its mechanisms of action where possible.
Physical and chemical properties of Eugenol
Eugenol belongs to a class of phenylpropanoids (C
10
H
12
O
2
). Te
IUPAC name of the compound is 4-Allyl-2-methoxyphenol (Figure 1),
having molecular mass 164.2g/mol with pKa=10.19 at 25°C. Eugenol
and isoeugenol are the two isoform of it. It is also known as caryophyllic
acid, allylguaiacol, 2-methoxy-4-(2-propenyl) phenol, 4-allylcatechol-
2-methyl ether. Te phenolic group confers the antioxidant property
of it. It is partially soluble in water and its solubility increases with
organic solvents. Te colour of the compound ranges from clear to pale
yellow [1,7]. Eugenol absorbed via small intestine when administered
orally and rapidly distributed in all organ when administered
intraperitoneally. According to Tompson et al. (1991), metabolism of
eugenol resulted in the formation of conjugates with sulfate, glucuronic
acid (major) and glutathione studied in vitro with 1mM concentration
(lethal dose). Eugenol is eliminated and excreted as expired CO
2
and
through urine studied in rabbit model (WHO, Food additive series 17
Eugenol, 1980).
Plant sources of Eugenol
Eugenol is extracted from several aromatic plants. Beside the
Eugenia caryophyllata, it is also isolated from Myristica fragrans,
Cinnamomum tamala, Zygium aromaticum, Ocimum basilicum,
Ocimum grattisimum, Ocimum tenuiforum, Pimenta racemosa etc.
However, the principal source is clove oil which contains 45–90%
eugenol of its constituent (Table 1) [1,8-10].
Isolation of Eugenol from plant
Eugenol was frst isolated in 1929 and commercial production
Figure 1: Chemical Structure of Eugenol.
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ISSN: 2153-2435
Pharmaceutica Analytica Acta