Content uploaded by Anbudhasan P
Author content
All content in this area was uploaded by Anbudhasan P on Jan 17, 2015
Content may be subject to copyright.
INTERNATIONAL JOURNAL OF FOOD
AND NUTRITIONAL SCIENCES
IMPACT FACTOR ~ 1.021
Official Journal of IIFANS
Volume 3, Issue 6, Oct-Dec 2014, www.ijfans.com e-ISSN: 2320-7876
INTERNATIONAL JOURNAL OF FOOD
AND NUTRITIONAL SCIENCES
The article can be downloaded from http:/www.ijfans.com/currentissue.html
225
e-ISSN 2320 –7876 www.ijfans.com
Vol.3, Iss.6, Oct-Dec 2014
© 2012 IJFANS. All Rights Reserved
Review Paper Open Access
NATURAL ANTIOXIDANTS AND ITS BENEFITS
P. Anbudhasan1*, A. Surendraraj2, S.Karkuzhali1 and S. Sathishkumaran1
1Department of Food Science and Technolgy, College of Food and Dairy Technology, Tamilnadu Veterinary and Animal
Science University, Chennai, Tamilnadu, India, 2Department of Fish Processing Technology, Tamilnadu Fisheries
University, Thootukudi, Tamilnadu, India.
*Corresponding Author: anbu4ps@gmail.com
Received on: 26th September, 2014 Accepted on: 17th December, 2014
Abstract
The consumer concern regarding the safety of using synthetic antioxidants in convenient food products has
forced and motivated the food processors to seek for natural alternatives. This leads to a situation where the
application of synthetic antioxidants started to decrease drastically in food products. Hence there has been a
increasing global trend towards the use of natural antioxidants present in fruits and green leafy vegetables. The
effects of these natural antioxidants in scavenging the free radicals are well discussed and reported in the earlier
studies. The factors that encourage the use of natural antioxidants are its low cost, compatibility with diet and less
harmful effect in the human body. The strong H-donating capacities of various phytochemicals make them as a
effective natural antioxidants. Phenols present in plant extracts acts as a potential antioxidant by inhibiting the free
radical formation and also prevent auto oxidation. Phenolic acids, flavonoids and volatile oils possess higher
antioxidant activity and also acts as the essential part of diet and this claims were supported by various scientific
evidence. The health promoting capacity of these natural antioxidants help in eradicating chronic diseases such as
cancer. Hence in this review the action of antioxidants on free radicals, occurrence, classification and potential health
effects of natural antioxidants was discussed.
Keywords: Natural foods; antioxidants; chronic diseases; cancer; phytochemical; phenols.
INTRODUCTION
It is unbelievable that oxygen, which is an
indispensable element for life, under certain situations
have severe deleterious effects on the human body. The
negative effects of oxygen are due to the formation and
activity of number of chemical compounds, known as
reactive oxygen species (ROS). Reactive oxygen species is
a collective term that includes all reactive forms of
oxygen, including both oxygen radicals and several non
radical oxidizing agents that participate in the initiation
and/or propagation of chain reaction (Shivkumar, 2011).
Many such reactive species are free radicals that represent
a class of highly reactive intermediate chemical entities
whose reactivity is derived from the presence of unpaired
electron in their structure. It is capable of independent
existence for very brief interval of time. It was found that a
wide variety of oxygen free radicals and other reactive
species are formed in the human body and food system
(Cui et.al., 2004). It was known that the quality of food
was attributed to various factors such taste, aroma, and
appearance. The convenient foods which meets this
attributes has led to the rapid growth in ready-to-eat
product category (Hofstrand, 2008). Many of such foods
contains ingredients that increases the nutritive value,
palatability and one of its kind was the polyunsaturated
fatty acids (PUFA) such as omega 3, omega 6 fatty acids
and the beneficial activity of which was well studied
(Simopoulos et.al., 1999; Ruxton et.al., 2004; Stephensen,
2004). Despite its higher nutritional value in foods, this
bioactive component is very much susceptible to quality
deterioration, especially under oxidative stress and
gradually forms free radicals. The action of free radicals
can, however, is blocked by antioxidant substances which
scavenge the free radicals and detoxify the organism. The
effort to reduce the free radical oxidation in food matrix
has increased by the addition of potential antioxidants,
below the consumable limit (Hillmann, 2010). The use of
plant extracts as natural antioxidants has received
increased interest due to the concerns on negative health
effects developed by the use of synthetic antioxidants
(Abramovic and Abram, 2006; Kowalski, 2007; Azizkhani
and Zandi, 2009). Synthetic antioxidants such as butylated
hydroxytoluene (BHT) and butylated hydroxyanisole
(BHA) are highly volatile and instable at elevated
temperature. The strict legislation on the use of synthetic
food additives, carcinogenic nature of some synthetic
antioxidants, and consumer preferences have shifted the
attention of manufacturers from synthetic to natural
antioxidants. Most of these natural antioxidants come from
fruits, vegetables, spices, grains, and herbs. Also, due to
NATURAL ANTIOXIDANTS AND ITS BENEFITS
P. Anbudhasan, A. Surendraraj, S.Karkuzhali and S. Sathishkumaran
The article can be downloaded from http:/www.ijfans.com/currentissue.html
226
toxicological concerns of synthetic antioxidants (Nakatani,
2000), phenolic compounds in plants were used to
minimize or retard lipid oxidation in lipid-based food
products. Fruits, vegetables and medicinal herbs are the
richest sources of antioxidant compounds such as Vitamin
A, C, E, betacarotene and important minerals (Sies et.al.,
1992). In addition, the call for sustainable source and also
the environmentally friendly production is forcing the food
industry to move in that direction (Berger, 2009).
OXIDATION
The utilization of oxygen to produce energy
through the metabolism of food nutrients acts as a
prerequisite for the survival of all living beings. While
oxygen is one of the most essential components for living,
it is also a highly reactive atom that is capable of becoming
part of potentially damaging molecules such as
hydroperoxyl radicals, superoxide anions, singlet oxygen,
hydrogen peroxide, organic peroxides, nitric oxide,
peroxynitrite and triplet oxygen. Oxygen uptake while
breathing causes free radical production and in addition to
that environmental factors such as pollutants, smoke and
certain chemicals also contribute to their formation (Fig-
1). In turn, these radicals can start chain reactions in cells
and it can cause damage or death to the cell (Srinivasan
et.al., 2008). This process also takes place in food matrix
that contain higher amount of lipids and affects its
stability. The components that have the antioxidant
property were intentionally added in lipid foods to
terminate the chain reactions by removing free radical
intermediates and inhibit other oxidation reaction.
Antioxidants normally neutralize the free radicals by being
oxidized themselves and act as reducing agents such
as thiols, ascorbic acid, or polyphenols. In the case of long
storage of foods such as ready to eat foods or processed
foods, additional antioxidant source must be added below
the consumable limit of human consumption to restrict the
formation of free radicals and keep the food safe.
Figure 1- Sources of free radicals and its consequences
in human body
FREE RADICAL
A free radical can be defined as, "any molecular
species capable of independent existence that contains an
unpaired electron in an atomic orbital and capture
electrons from other substances in order to neutralize
themselves" (Halliwell and Gutteridge, 1999). The
existence of an unpaired electron results in certain
common properties shared by most of the radicals (Lobo
et.al., 2010). The free radical has the ability of donating or
accepting an electron from other molecules (Cheeseman
and Slater, 1993). This will stabilizes the free radical at the
beginning but starts to produces another in the process.
Soon a chain reaction begins and thousands of free radical
reactions can occur within a few seconds on the primary
reaction (Shivkumar, 2011) (Fig-2). These reactive species
are capable of causing damage to the vital biological
molecules such as such as DNA, proteins, carbohydrates,
and lipids (Young and Woodside, 2001) and resulted in a
homeostatic disruption.
Figure 2. Mechanism for the formation of free radicals
FREE RADICAL BIOLOGY
The formation of free radicals occurs in the
human body as a consequence of enzymatic and non
enzymatic reactions. Enzymatic reactions, which serve as
source of free radicals, include those involved in the
respiratory chain, phagocytosis, prostaglandin synthesis,
and in the cytochrome P-450 system (Liu et.al., 1999). The
free radicals attack the healthy cells of the body and lead to
damage, disease and severe disorders. Cell damage caused
by free radicals appears to be a major contributor to aging
and disease (Harman, 1992) like cancer, heart disease,
decline in brain function and immune system. Plants and
animals maintain complex systems of multiple types of
antioxidants in order to prevent themselves from these
damages. Insufficient levels of antioxidants or inhibition of
the antioxidant enzymes cause oxidative stress and may
damage or kill cells. When this condition prevail, the ROS
molecule at higher concentration causes damage to cell
structures, nucleic acids, lipids and proteins (Valko et. al.,
2007). O2• − radical is responsible for lipid peroxidation
and also reduce the activity of enzyme antioxidant defence
system such as catalase (CAT) and glutathione peroxide
(GPx). HO2•, which is a protonated form of O2•− is more
reactive and able to cross the membrane and causes
damage to tissue. OH• radical is most reactive chemical
species and potent cytotoxic agent which attack and cause
damage to every molecule found in living tissue. HOCl
initiates the deactivation of antiproteases and activation of
latent proteases leading to tissue damage. It has ability to
damage biomolecules and also decomposes to liberate
toxic chlorine. Metal induced generation of ROS attack
DNA and other cellular components involving
NATURAL ANTIOXIDANTS AND ITS BENEFITS
P. Anbudhasan, A. Surendraraj, S.Karkuzhali and S. Sathishkumaran
The article can be downloaded from http:/www.ijfans.com/currentissue.html
227
polyunsaturated fatty acid residues of phospholipids,
which are extremely sensitive to oxidation. A Peroxyl
radical causes damage after rearranged via a cyclisation
reaction to endoperoxides. Studies show that free radicals
produce oxidation of the side chains of all amino acid
residues of proteins, particularly cysteine and methionine
(Valko et.al., 2007).
ANTIOXIDANTS
Antioxidants are compounds of many different
chemical forms, grouped together because they all have the
property of counteracting the effects of highly reactive,
harmful free radicals formed as the result of essential
oxidation reactions which normally takes place in food.
The possible mechanisms of action of antioxidants were
first explored when it was recognized that a substance with
anti-oxidative activity is likely to be the one that itself
readily oxidized. An antioxidant can be defined as: “any
substance that, when present in low concentrations
compared to that of an oxidisable substrate, delays or
inhibits the oxidation of that substrate” (Murthy, 2001).
Earlier the research on the role of antioxidants in biology
focused on its use in preventing the oxidation
of unsaturated fats, which is the cause of rancidity
(German, 1999). Many evidences from researches have
demonstrated that many natural products isolated from
plant sources possess antitumor properties (Wu et.al.,
2002). A variety of free radical scavenging antioxidants is
found in dietary source like fruits, vegetables, tea, etc.,
(Mandal et.al., 2009). Most importantly fruits can add
important vitamins, minerals, and other bioactive
compounds to the human diet (Vasco et.al., 2008). The
important commercially available natural antioxidants are
tocopherols (vitamin E), ascorbic acid (vitamin C) and
rosemary extract (Löliger, 1991; Trombino et.al., 2004).
Several natural phenolic compounds have been reported to
possess high antioxidant properties, but only a few of them
are found to be commercially applied in foods. The main
lipid-soluble antioxidants currently used in food are
monohydric or polyhydric phenols with various ring
substitutions. For maximum efficiency, primary
antioxidants are often used in combination with other
phenolic antioxidants or with various metal sequestering
agents, e.g. tocopherols with citric acid and isopropyl
citrate. The antioxidants obtained from plants are more
functional towards improving the shelf life of food
products and providing health promotion when compared
to materials whose antioxidants have been removed during
processing. Compounds such as β-carotene, ascorbic acids
have demonstrated to have antioxidant and synergistic
activity in despite of their non-phenolic structure (Hudson
and Mahgoub, 2006; Trombino et.al., 2004).
CLASSIFICATION OF ANTIOXIDANTS
The endogenous antioxidants are produced by
body to neutralize the free radicals and protect the body
from different disease. The endogenous antioxidant
defence systems classified into two groups such as
enzymatic and non enzymatic. Antioxidants that are
externally supplied to the body through food are said to be
exogenous antioxidants which plays important role to
protect the body. While there are dozens of known
antioxidants, two are absolutely indispensable, vitamins E
and C. These vitamins are partners in defence and they
have a synergistic relationship working together so that
their combined effect is greater than the sum of their
individual actions.
NATURAL ANTIOXIDANTS
Natural antioxidants are synthesised by plants
(e.g. Vitamins and other naturally-occurring chemicals in
our food) and are present in the foods we eat, as opposed
to those synthetic antioxidants that are either added to food
to extend its shelf-life (e.g. BHT). Natural antioxidants are
found in most fresh food, for e.g. When a cut apple turns
brown, that is through oxidation and the application of
lemon juice over the surface will slow the process. These
antioxidants are of high or low molecular weight, can
differ in their composition, their physical and chemical
properties and in their mechanism and site of action. They
can be divided into following categories:
ENZYMES
Enzymes such as superoxide dismutase (SOD),
catalase, and glutathione peroxidase attenuate the
generation of reactive oxygen species (ROS) by removing
potential oxidants or by transforming ROS/RNS into
relatively stable compounds. Superoxide dismutase is an
important endogenous antioxidant enzyme act as the first
line defence system against reactive oxygen species. It
catalyzes the transformation of the superoxide radical into
hydrogen peroxide, which can then be further transformed
by the enzyme catalase into water and molecular oxygen.
While superoxide anion in itself is not particularly
reactive, it can reduce transition metal ions, such as iron,
and it is converted to one of the most reactive radicals such
as the hydroxyl radical. Thus, elimination of superoxide
can attenuate the formation of the harmful hydroxyl radical
(Harris, 1992). Glutathione peroxidase (GPx) reduces lipid
peroxides (ROOH), formed by the oxidation of
polyunsaturated fatty acid (PUFA), to a stable, non-toxic
molecule-hydroxyl fatty acid (ROH). Together with
phospholipases GPx can also convert phospholipid
hydroperoxides (PL-OOH) into phospholipid hydroxide
(PL-OH) (Jacob, 1995). GPx present in the cytoplasm of
the cells removes H2O2 by coupling its reduction to H2O
with oxidation of GSH.
HIGH MOLECULAR WEIGHT PROTEINS
Proteins such as albumin, ceruloplasmin,
transferrin and haptoglobin, which are all present in
plasma, bind to redox active metals and limit the
production of metal-catalyzed free radicals. Albumin and
ceruloplasmin can bind copper ions, and transferrin binds
free iron. Haptoglobin binds heme-containing proteins and
can thus clear them from the circulation. Both free and
heme-associated proteins have pro-oxidant properties due
to their reaction with H2O2 to form ferryl species which
can easily initiate lipid peroxidation.
NATURAL ANTIOXIDANTS AND ITS BENEFITS
P. Anbudhasan, A. Surendraraj, S.Karkuzhali and S. Sathishkumaran
The article can be downloaded from http:/www.ijfans.com/currentissue.html
228
LOW MOLECULAR WEIGHT ANTIOXIDANTS
These antioxidants are subdivided into lipid-
soluble antioxidants such as tocopherol, carotenoids,
quinones, bilirubin, etc., and water-soluble antioxidants
such as ascorbic acid, uric acid and other polyphenols.
They delay or inhibit cellular damage mainly through their
free radical scavenging property. Tocopherols and
tocotrienols are the most important lipid-soluble
antioxidants present in vegetable oils (Holownia et.al.,
2001). Tocopherols and tocotrienols share the same ring
structure (Fig-3), the only difference being tocotrienols
have the unsaturated carbon chains. Tocopherols present in
crude vegetable oils survives the oil processing steps and
remains in sufficient quantities to provide oxidative
stability in the finished products. Tocopherols interrupt
free radical chain reaction by capturing free radicals
generated during oil auto oxidation. At high concentration,
tocopherols acts as a prooxidants (Angelo, 1996) and it
was found, at higher concentrations α-tocopherol (200-
2000ppm) may participate in two side reactions such as a)
Decomposition of hydroperoxides, b) Spontaneous
oxidation. The optimum tocopherol concentration to
inhibit peroxide formation should be established for a well
defined system.
Figure 3- Low molecular weight antioxidants
PLANTS DERIVED ANTIOXIDANTS
The dietary phytochemical antioxidants have the
ability to remove free radicals and it was revealed by
various animal studies. Phenolics are large and
heterogeneous groups of secondary plant metabolites that
are distributed throughout the plant kingdom. Compounds
that have several or many phenolic hydroxyl substituents
are often referred to as polyphenols.
There are hundreds of natural phenolic compounds have
been reported to possess high antioxidant property.
However their use in foods is limited by certain
requirements due to inadequate proof of safety. To achieve
the maximum efficiency certain primary antioxidants such
as tocopherols are used in combination with citric acid or
isopropyl citrate. It was reported that phenolic antioxidants
(PhH) can react with ROO• to generate ROOH and a
relatively unreactive phenoxyl radical (Ph•).
ROO· + PhH ROOH + Ph·
Ph· can subsequently undergo chain termination reactions
with ROO• to give non-radical products (Hashim et.al.,
1993).
ROO· + Ph· Non radical products
Thereby the phenolic substances acts as a chain-
breaking antioxidants by competing with the substrate
(RH) for the chain carrying peroxyl radicals. Vanillic,
caffeic, sinapic and coumaric acids are relatively
ubiquitous monohydroxylated phenolic acids whose
antioxidant capacities have been demonstrated (Taruscio
et.al., 2004). Some phenolic acids have the metal chelating
potential. Various berry items such as blueberry, mulberry,
strawberry, cloudberry and raspberry possess high contents
of hydroxy cinnamic acids, ellagic acid, ferulic acid and
various derivatives (Zadernowski et.al., 2005; Häkkinen
et.al., 1999) (Fig-4).
Figure 4- Structure of various phenolic acids
Some other berries such as bilberries, black
currents, cranberries displayed stronger antioxidative
properties, an especially bilberry was found to contain high
amount of hydroxycinnamic acid. The extract of different
berries such as crowberry, rowanberry, cloudberry,
cranberry, and whortleberry were found to inhibit the
formation of MeLo - conjugated diene hydroperoxides by
90%. The phenolic compounds present in the olive oils has
been analysed and the amount of phenolics depend on
variety, fruit maturity and the environmental conditions
(Torres et.al., 2005). The phenolics in the olive fruits are
characterized by the number of secoiridoid compounds
derived from p-hydroxyphenylethanol (tyrosol) and 3,4-
dihydroxyphenyletahnol (hydroxytyrosol) (Fig-5).
Figure 5- Structure of tyrosol and hydroxytyrosol
Flavonoids and tannins are the main phenolic
compounds (Rababah et.al., 2005). Flavonoids are the
natural polyhydroxylated aromatic compounds vastly
present in the plant system including fruits and vegetables.
The polyphenolic compounds, such as flavonoids and
catechin present in edible plants, exhibit potent antioxidant
NATURAL ANTIOXIDANTS AND ITS BENEFITS
P. Anbudhasan, A. Surendraraj, S.Karkuzhali and S. Sathishkumaran
The article can be downloaded from http:/www.ijfans.com/currentissue.html
229
activities and it was reported in the earlier studies (Fang
et.al., 2002). It constitutes about 2/3 of the polyphenols
that we obtain in our diet. On an average human consume
1g/day of flavonoids and it was estimated (Das and
Ramanathan, 1992). The efficiency of different flavonoids
depends on the structure and their relationship was
investigated (Bors et.al., 1992) (Fig-6).
Figure 6-Structure of flavonoids and its derivatives
based on R1 and R2 substitutions
They scavenge the reactive free radicals,
including hydroxyl, peroxyl and superoxide radicals
(Hopia and Heinonen, 1999) and to deactivate catalytic
metals due to complexation (Afanasèv et.al., 2000). They
also inhibit the activity of lipoxygenase and
cyclooxygenase enzymes and its increase in blood plasma
decreased the level of LDL cholesterol oxidation (Torres
et.al., 2005). The carotenoid, such as carotene and
cryptoxanthin of plant origins, exerts potential antioxidant
effect on oil rich food systems (Aruoma, 1998). For
example, carotene reacts with a peroxyl radical to form a
resonance-stabilized carbon-centered radical, thereby
inhibiting the chain propagation effect of ROS. It was
reported that lycopene, lutein, canthaxanthin, and
zeaxanthin possess antioxidant action similar to, or even
greater than, those of carotene (Aruoma, 1998). It was
found, a diet rich in brussels sprouts (300 g/d) markedly
decreases the urinary excretion of 8-
hydroxydeoxyguanosine in humans, indicating a reduction
of DNA oxidation (Lei, 2002). Similarly, dietary
supplementation of cabbage and broccoli extracts to rats
decreases free radical-induced tissue damage brought
about by irradiation. Moreover, phytic acid has a high
chelation potential and can be supplemented to diets for
suppressing iron-catalyzed oxidative reactions and
potentially for reducing the incidence of colonic cancer
and inflammatory bowel disease (Graf and Eaton, 1990).
Collectively, these studies suggest that phytochemical may
be used as effective antioxidants for improving human
health and preventing carcinogenesis and cardiovascular
disease.
SYNTHETIC ANTIOXIDANTS
Synthetic antioxidants are widely used as food
additives to prevent rancidification, owing to their high
performance and wide availability. Synthetic antioxidants
such as butylated hydroxyanisole (BHA), tertiary butyl
hydroquinone (TBHQ), 2,4,5-trihydroxybutyrophenone
(THBP), propyl gallate (PG), octyl gallate (OG),
nordihydroguaiaretic acid (NDGA) and 4-hexylresorcinol
(4HR) are used in edible vegetable oil and cosmetics
(Guan et.al., 2005; Nazni et.al., 2013;Guo et.al., 2006).
Propyl gallate and butylated hydroxyanisole, as synthetic
phenolic antioxidants, had a higher chemical activity for
suppressing chain initiation of the oxidation of unsaturated
fatty acids. Although they are powerful in protecting
product quality in food distribution, excess antioxidants
added to food might produce toxicities or mutagenicities,
and thus endanger the health of people. Based on the type
of fat and oil in food, antioxidant will be chosen. BHA and
BHT dissolves in most fats and oils and best suited to
animal fats. When used as a combination in foods, it
imparts a beneficial effect rather than using it alone. In
contrast, propyl gallate which is not readily soluble, is
more effective in vegetable oils than are BHA and BHT.
TBHQ is the most effective antioxidant for retarding
oxidation in unsaturated fats like vegetable oils. Oxidative
stability can be achieved with lower levels of TBHQ than
that of other synthetic antioxidants (Fig-7).
Figure 7- Structure of Butylated Hydroxy Toluene and
Butylated Hydroxy Anisole
NATURAL AND SYNTHETIC ANTIOXIDANTS
Antioxidants such as natural and synthetic, are
used by the food industry as food additives to help prolong
the shelf life and appearance of many foodstuffs. Synthetic
phenolic antioxidants (butylated hydroxyanisole [BHA],
butylated hydroxytoluene [BHT], and propyl gallate)
effectively inhibit oxidation, for e.g.: chelating agents such
as ethylene diamine tetra acetic acid (EDTA), can bind
metals reducing their contribution to the process.
Antioxidants also occur naturally in many foods and are
essential for our health. They include Vitamin C found in
fruit and vegetables and vitamin E found in seeds and nuts.
Some vitamins (ascorbic acid and α-tocopherol), many
herbs and spices (rosemary, thyme, oregano, sage, basil,
pepper, clove, cinnamon, and nutmeg), and plant extracts
(tea and grapeseed) contain antioxidant components as
well. While use of synthetic antioxidants (such as
butylated hydroxytoluene and butylated hydroxyanisole) to
maintain the quality of ready-to-eat food products has
become commonplace, consumer concern regarding their
NATURAL ANTIOXIDANTS AND ITS BENEFITS
P. Anbudhasan, A. Surendraraj, S.Karkuzhali and S. Sathishkumaran
The article can be downloaded from http:/www.ijfans.com/currentissue.html
230
safety has motivated the food industry to seek natural
antioxidants. The antioxidants that have caused health
problems, for some people, are primarily synthetic. The
most problematic antioxidants appear to be BHA, BHT
and TBHQ, with gallates in second place and have been
used in food products, with some restrictions, since the late
1950s. TBHQ is a more recent addition to the list of
antioxidants allowed in food, in Europe, it became an
accepted antioxidant for food use in 2004. BHA, BHT, and
TBHQ are used in a variety of products but are most
commonly found in foods that contain oil and fat. Their
action is similar to that of Vitamin E which is used in some
of the same type of products as an alternative antioxidant.
These antioxidants sometimes appear alone in a food but
are often used in combination with other chemicals that
also have an antioxidant activity including propyl gallate,
citric acid, phosphoric acid, and ascorbic acid.
HEALTH CONCERNS OF SYNTHETIC
ANTIOXIDANTS
Whilst the majority of studies have been carried
out on animals, there is still quite a large body of research
that has identified problems with these synthetic
antioxidants for humans. The table (Table-1) below lists
some of the health problems in humans that have been
linked with adverse reactions to BHA, BHT and/or TBHQ.
Table 1- Adverse reactions to BHA, BHT and/or TBHQ
Asthma
Joint pains
Angioedema
Rhinitis
Dermatitis
Undescended testes
Stomach problems
Vasculitis
Eye problems
Obesity
Excessive sweating
Urticaria
In a study involves seven individuals with
reactions to BHA and BHT reported with symptoms
included vasomotor rhinitis, headache, flushing, asthma,
conjunctival suffusion, dull retrosternal (behind the
breastbone) pain radiating to the back, diaphoresis
(excessive sweating), or somnolence (sleepiness). In a later
study, identifying cross reactivity with aspirin, they found
twenty-one people intolerant to BHA and BHT. These
synthetic antioxidants have been found to cause dermatitis
in a number of people (Le Coz and Schneider, 1987). In
one study, contact dermatitis was caused by TBHQ in a
hair dye and cross sensitization with BHA and BHT was
noted. The US Department of Health and Human Services
states in their report on Carcinogens that BHA is
“reasonably anticipated to be a human carcinogen based on
sufficient evidence of carcinogenicity in experimental
animals”. There is also concern that “BHT may convert to
other substances in the human body that may be
carcinogenic. For example, one conversion product of
BHT (the hydroperoxide form) has been shown to disrupt
the chemical signals that are sent from cell to cell.
CONCLUSION
Antioxidants are almost ubiquitous in commonly
consumed food products, as they are generally pre-existing
compounds in the form of natural antioxidants, or are
added during processing as synthetic antioxidants. As
natural antioxidants have been shown to have significant
benefits in preventing cancer and heart disease, many food
advertisers have taken note and begun publicizing this fact.
Antioxidant content in foods has achieved prominence on
many food labels, ranging from fruit juices to chocolate
products. As long as they are consumed in moderate
concentrations, natural antioxidants have been proven to
have many positive health effects, such as preventing
plaque formation in the arteries and preventing other
chronic conditions such as cancer and heart disease. These
beneficial properties have put natural antioxidants on the
forefront of recent food advertising, and public levels of
awareness concerning natural antioxidants and their
positive effects have increased significantly. Unlike natural
antioxidants, however, synthetic antioxidants have been
shown to have potential toxic effects on the health of
consumers. Additionally, synthetic antioxidants are not
advertised prominently on food labels and the number of
studies done on public awareness of the synthetic
antioxidants and their health effects is sparse, in direct
contrast to the focus placed on the natural antioxidant
content of food items. This lack of interest and inquest has
led synthetic antioxidants to be the subject of few studies,
particularly those assessing the public’s awareness of their
presence and toxic effects. On the basis of this review
following conclusions can be drawn, 1. Free radicals are
very harmful to human health and can cause several
degenerative diseases like diabetes, cancer, atherosclerosis,
hypertension etc. 2. Various kinds of antioxidants
particularly from natural sources such as enzymes,
tocopherol, carotenoids, ascorbic acid, polyphenols etc.
inhibit the cellular damage mainly through free radical
scavenging property.
REFERENCES
Abramovic H, Abram V. Effect of added rosemary
extract on oxidative stability of Camelina sativa oil.
Acta Agri. Slov. 2006; 87:255-261.
Graf E, Eaton JW. Antioxidant functions of phytic
acid. Free Radi. Bio. Med. 1990; 8(1):61-69.
Guan YQ, Chu QC, Fu L, Ye JN. Determination of
antioxidants in cosmetics by micellar electrokinetic
capillary chromatography with electrochemical
detection. J. of Chromatography. 2005; 1074(2):201–
204.
Torres MM, Martinez MM, Maestri DM. A
multivariate study of the relationship between fatty
acids and volatile flavor components in olive and
walnut oils. J. of the Am. Oil Che. Soc. 2005. 82:105-
110.
Afanasev JB, Dorozhko AJ, Brodskill AV, Kostyuk
VA, Patapovitch AI. Chelating and free radical
scavenging mechanisms of inhibitory action of rutin
and quercetin in lipid peroxidation. Biochem
Pharmacol. 1989; 38:1763–9.
NATURAL ANTIOXIDANTS AND ITS BENEFITS
P. Anbudhasan, A. Surendraraj, S.Karkuzhali and S. Sathishkumaran
The article can be downloaded from http:/www.ijfans.com/currentissue.html
231
Angelo AJ. Lipid oxidation in foods. Crit. Rev. Food
Sci. Nut. 1996; 36: 175.
Aruoma OI. Free radicals, oxidative stress, and
antioxidants in human health and disease. J. Am.
Chem. Soc. 1998;75:199
Azizkhani M, Zandi P. Effects of some natural
antioxidants mixtures on margarine stability. World
Aca. of Sci. Engg. and Tech. 2009; 49:93-96
Berger RG. Biotechnology of flavours-the next
generation. Biotech Letter. 2009; 31(11):1651–1659.
Bors W, Heller W, Muchel C, Saran M. Structural
Principles of Flavonoid Antioxidants. Springer Link.
1992; 77-95
Cheeseman KH, Slater TF. An introduction to free
radicals chemistry. Br. Med. Bull. 1993; 49:481–93.
Cui K, Luo X, Xu K, Murthy MR. Role of oxidative
stress in neurodegeneration recent developments in
assay methods for oxidative stress and nutraceutical
antioxidants. Prog. Neuro-Psycho pharma. Bio. Psych.
2004; 28: 771-799.
Das NP, Ramanathan L. Studies on Flavonoids and
related compounds as antioxidants in food. In Lipid-
Soluble Antioxidants. Biochemistry and Clinical
Applications. 1992; 295-306.
Fang YZ, Sheng Y, Guoyao Free radicals,
antioxidants and nutrition. Theory and application of
free radical biology. 2002; 18(10):872-879.
German JB. Food processing and lipid
oxidation. Advances in experimental medicine and
biology. Adv. in Exp. Med. and Bio. 1999; 459:23-50.
Guo L, Xie MY, Yan AP, Wan YQ, Wu YM.
Simultaneous determination of five synthetic
antioxidants in edible vegetable oil by GC–MS. Anal.
and Bioanal. Chem. 2006; 386(6):1881–1887.
Häkkinen S, Heinonen M, Kärenlampi S, Mykkänen
H, Ruuskanan J, Törrönnen R. Content of flavonols
quercetin, myricetin and kaempferol in 25 edible
berries. J. of Agri. and Food Chem. 1999; 47(6):2274-
2279.
Halliwell B, Gutteridge JMC. Free Radicals in
Biology and Medicine, Clarendon Press, Oxford;
1999.
Harman D. Role of free radicals in aging and diseases.
Ann. of New York Aca. of Sci. 1992; 673:126-141
Harris ED. Regulation of antioxidant enzymes, The J.
of Nutrition. 1992; 122:625-626.
Hashim IB, Koehler PE, Eitenmiller RR. Tocopherols
in runner and Virginia peanut cultivars at various
maturity stages. J. Am. Oil Chem. Soc. 70:633-635.
Hillmann J. Reformulation key for consumer appeal
into the next decade. Food Rev. 2010; 37(1):18–19.
Hofstrand D. Domestic perspectives on food versus
fuel. 2010 (cited 2010 Feb) Available from:
www.agmrc.org. Accessed
Holownia KI, Erickson MC, Chinnan MS, Eitenmiller
RR. Tocopherol losses in peanut oil during pressure
frying of marinated chicken strips coated with edible
films. Food Res. Int. 2001; 34:77-80.
Hopia A, Heinonen M. Antioxidant activity of
flavonol aglycones and their glycosides in methyl
linoleate. J. Am. Oil Chem. Soc. 1999; 76:139–144.
Hudson BJF, Mahgoub SEO. Naturally-occuring
antioxidants in leaf lipids. J. Sci. Food Agric. 2006;
31:646-650
Jacob RA. The integrated antioxidant system.
Nutrition Research. 1995; 15:755-766.
Kowalski R. GC analysis of changes in the fatty acid
composition of sunflower and olive oils heated with
quercetin, caffeic acid, protocatechuic acid and
butylated hydroxylanisole. Acta Chromatogr. 2007;
18:15-23.
Le Coz CJ, Schneider GA. Contact dermatitis from
tertiary butylhydroquinone in a hair dye with cross
sensitivity to BHA and BHT. Contact Dermatitis
1987; 17:257-258.
Lei XG. In vivo antioxidant role of glutathione
peroxidase: evidence from knockout mice. Methods
Enzymol 2002; 347:213.
Liu T, Stern A, Roberts LJ. The isoprostanes: Novel
prostanglandin-like products of the free radical
catalyzed peroxidation of arachidonic acid. J. Biomed.
Sci. 1999;6: 226–35.
Lobo V, Patil A, Chandra PN. Free radicals,
antioxidants and functional foods: Impact on human
health. Pharmacogn Rev. 2010; 4(8):118–126.
Loliger J. The use of antioxidants in food. Free
Radicals and Food Additives. 1991; 121-150.
Mandal S, Yadav S, Yadav S, Nema RK. Antioxidant
a review. Journal of chemical and pharmaceutical
research. 2009; 1(1):102-104.
Murthy KNC. Evaluation of antioxidant activity of
pomegranate (Punicagranatum) and grapes (Vitis
vinifera), thesis, Rajeev Gandhi Univ. of Health
Science, (India, 2001).
Nazni.P and Dharmaligam.R, Isolation And
Separation Of Phenolic Compound From Coriander
Flowers, International Journal of Agricultural and
Food Science, 2013; Vol.4, Iss.1, pp. 13-21.
Nakatani N. Phenolic antioxidants from herbs and
spices. BioFactors. 2000; 13: 141-146.
Rababah T.M, Ereifej KI, and Howard L. Effect of
ascorbic acid and dehydration on concentrations of
total phenolics, antioxidant capacity, anthocyanins,
NATURAL ANTIOXIDANTS AND ITS BENEFITS
P. Anbudhasan, A. Surendraraj, S.Karkuzhali and S. Sathishkumaran
The article can be downloaded from http:/www.ijfans.com/currentissue.html
232
and color in fruits. J. Agric. Food Chem. 2005;53
(11): 4444–4447.
Ruxton CH, Reed SC, Simpson MJ, Millington K.J,
The health benefits of omega-3 polyunsaturated fatty
acids: a review of the evidence. J. Hum. Nutr. Diet,
2004; 17: 449–459.
Shivkumar. Free Radicals and Antioxidants: Human
and Food System. Advances in Applied Science
Research. 2011; 2 (1): 129-135.
Sies H, Stahl W, Sundquist AR, Antioxidant function
of vitamins, vitamins E and C, beta-carotene, and
other carotenoids, Ann. of the New York Aca. of Sci.
1992; 669:7-20.
Simopoulos AP, Leaf A, Salem N. Essentiality of and
recommended dietary intakes for omega-6 and omega-
3 fatty acids. Ann. Nutr. Metab. 1999; 43:127–130.
Srinivasan O, Parkin KL, Fennema O, editors. 2008.
Fennema’s food chemistry. 4th ed. Boca Raton, Fla.:
CRC Press. p 1144.
Stephensen CB. Fish oil and inflammatory disease.
Nutr. Rev. 2004; 62:486–489.
Taruscio TG, Barney DL, Exon J. Content and profile
of flavonoid and phenolic acid compounds in
conjunction with the antioxidant capacity for a variety
of Northwest Vaccinium berries. J. Agric. Food Chem.
2004; 52:3169-3176.
Trombino S, Serini S, Di Nicuolo F, Celleno L, Andò
S, Picci N, Calviello G, Palozza P. Antioxidant effect
of ferulic acid in isolated membranes and intact cells:
synergistic interactions with alpha-tocopherol, beta-
carotene, and ascorbic acid. J. Agric. Food Chem.
2004; 52(8): 2411-20.
Valko M, Leibfritz D, Moncol J, Cronin MTD, Mazur
M, Telser J. Free radicals and antioxidants in normal
physiological functions and human disease. The Inter.
J. of Biochemistry & Cell Biology. 2007; 39:44–84.
Vasco C, Ruale J, Kamal-Eldin A. Total phenolic
compounds and antioxidant capacities of major fruits
from Ecuador. Food Chemistry. 2008; 111:816-823.
Wu J, Wu Y, Yang BB. Anticancer activity of
Hemsleya amabilis extract. Life Sciences. 2002;
71:2161–2170.
Young IS, Woodside JV. Antioxidants in health and
disease. J. Clin. Pathol. 2001; 54:176–86.
Zadernowski R, Naczk M, Nesterowicz J. Phenolic
acid profiles in small berries. J. Agric. Food. Chem.
2005; 53:2118.
