Free radicals, antioxidants, Diseases and phytomedicines: Current status and Future prospect

Abstract

Free radicals are well documented for playing a dual role in our body as both deleterious and beneficial species. In low/moderate concentrations free radicals are involved in normal physiological functions but excess production of free radicals or decrease in antioxidant level leads to oxidative stress. It is a harmful process that can be mediates damage to cell structures, including lipids, proteins, RNA and DNA which leads to number of diseases. A variety of synthetic medicine employed in the treatment of different diseases also capable to generate free radicals in body which may causes another disease. The plant sources are rich of antioxidants, phyto-constituents are capable to terminate free radical reactions and prevent our body from oxidative damage. Vegetables and fruits are also important sources of antioxidant substances. Different phytoconstituents and herbal product which are safer then synthetic medicine and beneficial in the treatment of diseases caused by free radicals, it also protect the body by prevent the free radicals to cause tissue injury. Phytoconstituents are conferring less side effect and compatible to body physiology. Therefore it is demand of modern era to use such phytoconstituents or phytomedicines.

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Volume 3, Issue 1, July – August 2010; Article 021 ISSN 0976 – 044X
International Journal of Pharmaceutical Sciences Review and Research Page 91
Available online at www.globalresearchonline.net
FREE RADICALS, ANTIOXIDANTS, DISEASES AND PHYTOMEDICINES:
CURRENT STATUS AND FUTURE PROSPECT
Saikat Sen
1*
, Raja Chakraborty
1
, C. Sridhar
1
, Y. S. R. Reddy
1
, Biplab De
2
1
C.E.S. College of Pharmacy, Kurnool, Andra Pradesh -518 218, India.
2
Regional Institute of Pharmaceutical Science and Technology, Agartala, Tripura - 799 005, India.
*Email: saikat.pharm@rediffmail.com
ABSTRACT
Free radicals are well documented for playing a dual role in our body as both deleterious and beneficial species. In low/moderate
concentrations free radicals are involved in normal physiological functions but excess production of free radicals or decrease in
antioxidant level leads to oxidative stress. It is a harmful process that can be mediates damage to cell structures, including lipids,
proteins, RNA and DNA which leads to number of diseases. A variety of synthetic medicine employed in the treatment of different
diseases also capable to generate free radicals in body which may causes another disease. The plant sources are rich of antioxidants,
phyto-constituents are capable to terminate free radical reactions and prevent our body from oxidative damage. Vegetables and fruits are
also important sources of antioxidant substances. Different phytoconstituents and herbal product which are safer then synthetic medicine
and beneficial in the treatment of diseases caused by free radicals, it also protect the body by prevent the free radicals to cause tissue
injury. Phytoconstituents are conferring less side effect and compatible to body physiology. Therefore it is demand of modern era to use
such phytoconstituents or phytomedicines.
Keywords: Free radicals, Antioxidants, Oxidative stress, Diseases, Phytoconstituents.
INTRODUCTION
Oxygen is an element obligatory for life, living systems
have evolved to survive in the presence of molecular
oxygen and for most biological systems. Oxidative
properties of oxygen play a vital role in diverse biological
phenomena. Oxygen has double-edged properties, being
essential for life; it can also aggravate the damage within
the cell by oxidative events
1
.
Free radicals and its adverse effects were discovered in the
last decade. These are dangerous substances produced in
the body along with toxins and wastes which are formed
during the normal metabolic process of the body. The
body obtained energy by the oxidation of carbohydrates,
fats and proteins through both aerobic and anaerobic
process leads the generation of free radicals.
Overproduction of the free radicals can responsible for
tissue injury. Cell membranes are made of unsaturated
lipids and these unsaturated lipid molecules of cell
membranes are particularly susceptible to free radicals.
Oxidative damage can direct to a breakdown or even
hardening of lipids, which composition of all cell walls.
Breakdown or hardening is due to lipid peroxidation leads
to death of cell or it becomes unfeasible for the cell to
properly get its nutrients or get signals to achieve another.
In addition, other biological molecules including RNA,
DNA and protein enzymes are also susceptible to
oxidative damage. Environmental agents also initiate free
radical generation leads different complication in body.
The toxicity of lead, pesticides, cadmium, ionizing
radiation, alcohol, cigarette smoke, UV light and pollution
may all be due to their free radical initiating capability
2-4
.
Anti-oxidants are substances capable to mop up free
radicals and prevent them from causing cell damage. Free
radicals are responsible for causing a wide number of
health problems which include cancer, aging, heart
diseases and gastric problems etc. Antioxidants cause
protective effect by neutralizing free radicals, which are
toxic byproducts of natural cell metabolism. The human
body naturally produces antioxidants but the process is not
100 percent effective in case of overwhelming production
of free radicals and that effectiveness also declines with
age
5,6
.
Increasing the antioxidant intake can prevent diseases and
lower the health problems. Research is increasingly
showing that antioxidant rich foods, herbs reap health
benefits. Foods may possibly enhance antioxidant levels
because foods contain a lot of antioxidant substances.
Fruits and vegetables are loaded with key antioxidants
such as vitamin A, C, E, betacarotene and important
minerals, including selenium and zinc. Fruits, vegetables
and medicinal herbs are the richest sources of antioxidant
compounds
7
. Herbs are staging a comeback and herbal
‘renaissance’ is happening all over the world. The herbal
products today symbolize safety also compatible with
human normal physiology. Natural products, mainly
obtained from dietary sources provide a large number of
antioxidants. Phytoconstituents are also important source
of antioxidant and capable to terminate the free radical
chain reactions
8,9
.
FREE RADICALS, REACTIVE OXYGEN AND
NITROGEN SPECIES
A free radical may defined as a molecule or molecular
fragments containing one or more unpaired electrons in its
outermost atomic or molecular orbital and are capable of
independent existence
10
. Reactive oxygen species (ROS)
and reactive nitrogen species (RNS) are describes free
radicals and other non-radical reactive derivatives. The
reactivity of radicals is generally stronger than non-radical

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species though radicals are less stable
11
. Free radicals are
formed from molecules by the homolytic cleavage of a
chemical bond and via redox reactions, once formed these
highly reactive radicals can start a chain reaction
12,13
.
ROS and RNS includes radicals such as superoxide (O
2
•−
),
hydroxyl (OH
•
), peroxyl (RO
2
•
), hydroperoxyl (HO
2
•
),
alkoxyl (RO
•
), peroxyl (ROO
•
), nitric oxide (NO
•
),
nitrogen dioxide (NO
2
•
) and lipid peroxyl (LOO
•
); and
non radicals like hydrogen peroxide (H
2
O
2
), hypochlorous
acid (HOCl), ozone (O
3
), singlet oxygen (
1
Δg),
peroxynitrate (ONOO
−
), nitrous acid (HNO
2
), dinitrogen
trioxide (N
2
O
3
), lipid peroxide (LOOH)
11
. Non radicals are
also termed as oxidants and capable to lead free radical
reactions in living organisms easily. Radicals are derived
from oxygen characterize as the most important class of
radical species generated in living systems
13,14
.
At high concentrations, ROS can be important mediators
of damage to cell structures, nucleic acids, lipids and
proteins
15
. O
2
• −
radical is responsible for lipid
peroxidation and also have the capability to decrease the
activity of other antioxidant defense system enzyme such
as catalase (CAT) and glutathione peroxide (GPx), it
causes damage to the ribonucleotide which is required for
DNA synthesis. The protonated form of O
2
•−
is HO
2
•
,
which is more reactive and able to cross the membrane
and causes damage to tissue. OH
•
radical is most reactive
chemical species. It is a potent cytotoxic agent and able to
attack and damage almost every molecule found in living
tissue. H
2
O
2
is not a radical but it produces toxicity to cell
by causing DNA damage, membrane disruption and
release calcium ions within cell, resulting in calcium
dependent proteolytic enzyme to be activated. HOCl is
produced by the enzyme myeloperoxidase in activated
neutrophils and initiates the deactivation of antiproteases
and activation of latent proteases leading to tissue
damage
10
. It has ability to damage biomolecules, directly
and also decomposes to liberate toxic chlorine. Metal
induced generation of ROS attack DNA and other cellular
components involving polyunsaturated fatty acid residues
of phospholipids, which are extremely sensitive to
oxidation
16
. Peroxyl radicals 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
15,17
.
Free radical reactions
Free radicals generally involved in chain reactions, a series
of reactions leads to regenerates a radical that can begin a
new cycle of reactions. Free radical reactions take three
distinct identifiable steps
18
.
 Initiation step: formation of radicals.
 Propagation step: in this step required free radical is
regenerated repeatedly as a result of chain reaction,
which would take the reaction to completion.
 Termination step: destruction of radicals
Generation and sources of free radicals
Free radicals can be formed from both endogenous and
exogenous substances. They are continuously forming in
cell and environment. Different sources of free radicals are
as follows
13,19-22
:
 UV radiations, X-rays, gamma rays and microwave
radiation.
 Metal-catalyzed reactions.
 Oxygen free radicals in the atmosphere considered
as pollutants.
 Inflammation initiates neutrophils and macrophages
to produce ROS and RNS.
 Neutrophils stimualated by exposure to microbes.
 In mitochondria-catalyzed electron transport
reactions, oxygen free radicals produced as by
product.
 ROS formed from several sources like
mitochondrial cytochrome oxidase, xanthine
oxidases, neutrophils and by lipid peroxidation.
 ROS generated by the metabolism of arachidonic
acid, platelets, macrophages and smooth muscle
cells.
 Interaction with chemicals, automobile exhausts
fumes, smoking of cigarettes, cigars, beedie.
 Burning of organic matter during cooking, forest
fires, volcanic activities.
 Industrial effluents, excess chemicals, alcoholic
intake, certain drugs, asbestos, certain pesticides
and herbicides, some metal ions, fungal toxins and
xenobiotics.
ANTIOXIDANTS
Antioxidants are any substance that delay or inhibits
oxidative damage to a target molecule. At a time one
antioxidant molecule can react with single free radicals
and are capable to neutralize free radicals by donating one
of their own electrons, ending the carbon-stealing reaction.
Antioxidants prevent cell and tissue damage as they act as
scavenger. Cell produce defense against excessive free
radicals by their preventative mechanisms, repair
mechanisms, physical defenses and antioxidant defenses
23
.
A variety of components act against free radicals to
neutralize them from both endogenous and exogenous in
origin
23
. These include:
 Endogenous enzymatic antioxidants.
 Non enzymatic, metabolic and nutrient
antioxidants.
 Metal binding proteins like ferritin, lactoferrin,
albumin and ceruloplasmin.
 Phytoconstituents and phytonutrients.
The body produces different antioxidants (endogenous
antioxidants) to neutralize free radicals and protect the

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body from different disease leads by the tissue injury.
Exogenous antioxidants are externally supply to the body
through food also plays important role to protect the body.
The body has developed several endogenous antioxidant
defense systems classified into two groups such as
enzymatic and non enzymatic. The enzymatic defense
system includes different endogenous enzymes like
superoxide dismutase (SOD), catalase (CAT), glutathione
peroxidase (GPx), glutathione reductase (GR) and non
enzymatic defense system included vitamin E, vitamin C
and reduced glutathione (GSH)
23,24
.
SOD is an important endogenous antioxidant enzyme act
as the first line defense system against ROS which
scavenges superoxide radicals to H
2
O
2
. GPx present in the
cytoplasm of the cells removes H
2
O
2
by coupling its
reduction to H
2
O with oxidation of GSH. GR is a
flavoprotein enzyme, regenerates GSH from oxidized
glutathione in the presence of NADPH. GSH is a
tripeptide and a powerful antioxidant present within the
cytosol of cells and is the major intracellular nonprotein
thiol compound (NPSH). SH groups present in GSH to
react with H
2
O
2
and the OH
•
radical and prevent tissue
damage and GSH is also capable of scavenging ROS
directly or enzymatically via GPx. Vitamins C and E are
non-enzymatic endogenous antioxidant also exists within
normal cells and react with free radicals to form radicals
themselves which are less reactive than the radicals. They
break radical chain reactions by trapping peroxyl and other
reactive radicals
16,20,25
.
Non-enzymatic antioxidants also can be divided into
metabolic antioxidants and nutrient antioxidants.
Metabolic antioxidants are the endogenous antioxidants,
which produced by metabolism in the body like lipoid
acid, glutathione, L-ariginine, coenzyme Q10, melatonin,
uric acid, bilirubin, metal-chelating proteins, transferrin
etc
125,26
. While nutrient antioxidants belonging to
exogenous antioxidants, which cannot be produced in the
body but provided through diet or supplements viz. trace
metals (selenium, manganese, zinc), flavonoids, omega-3
and omega-6 fatty acids etc
11
. Vitamin E and C are the non
enzymatic antioxidants exist within normal cells as well as
they can be supplied through diet
27
.
Antioxidants may exert their activity by several
mechanisms, like by suppressing the production of active
species by reducing hydroperoxides and H
2
O
2
, by
sequestering metal ions, termination of chain reaction by
scavenging active free radicals and also caused repairing
and/or clearing damage of cell. Biosynthesis of other
antioxidants or defense enzymes also induced by some
antioxidants
27,28
. Therefore antioxidant synthesized in
body or supplied from outside like phytoconstituents plays
important role to protect the body from free radical
induced injury.
OXIDATIVE STRESS AND HUMAN HEALTH
Free radicals are fundamental to any biochemical process
and represent an essential part of aerobic life and our
metabolism. They are continuously produced by the body
via enzymatic and non-enzymatic reactions like
respiratory chain reaction, the phagocytosis, prostaglandin
synthesis, cytochrome P450 system and oxidative
phosphorylation (i.e. aerobic respiration) in the
mitochondria
28,29,30
.
ROS and RNS are the products of normal cellular
metabolism, having both deleterious and beneficial effect
in the body
31
. At low or moderate concentration some of
the free radicals plays beneficial physiological role in vivo
this include defense against infectious agents by
phagocytosis, energy production, cell growth, function in
different cellular signaling systems and the induction of a
mitogenic response at low concentrations
3,32
.
Free radicals occur continuously in all cells as part of
normal function. Oxygen free radicals are detrimental to
the integrity of biological tissue and mediate their injury.
The mechanism of damage involves lipid peroxidation,
which destroys cell structures, lipids, proteins and nucleic
acids. They causes damage to cell membranes with the
release of intracellular components, leading to further
tissue damage
32,33
. Antioxidant enzymes and non-
enzymatic defense system minimizes the harmful effect of
ROS by various antioxidant mechanism.
Oxidative stress is a harmful condition that occurs when
there is an excess of ROS and/or a decrease in antioxidant
levels, this may caused tissue damage by physical,
chemical, psychological factors that lead to tissue injury in
human and causes different diseases
34
. Living creatures
have evolved a highly complicated defense system and
body act against free radical-induced oxidative stress
involve by different defense mechanism like preventative
mechanisms, repair mechanisms, physical defenses and
antioxidant defenses
15
.
Oxygen derived free radical reactions have been
implicated in the pathogenesis of many human diseases
including
11,15,35-41
:
 Neurodegenerative disorder like alzheimer’s
disease, parkinson’s disease, multiple sclerosis,
amyotrophic lateral sclerosis, memory loss and
depression.
 Cardiovascular disease like atherosclerosis,
ischemic heart disease, cardiac hypertrophy,
hypertension, shock and trauma.
 Pulmonary disorders like inflammatory lung
diseases such as asthma and chronic obstructive
pulmonary disease.
 Diseases associated with premature infants,
including bronchopulmonary, dysplasia,
periventricular leukomalacia, intraventricular
hemorrhage, retinopathy of prematurity and
necrotizing enterocolitis.
 Autoimmune disease like rheumatoid arthritis.
 Renal disorders like glomerulonephritis and
tubulointerstitial nephritis, chronic renal failure,
proteinuria, uremia.
 Gastrointestinal diseases like peptic ulcer,
inflammatory bowel disease and colitis.
 Tumors and cancer like lung cancer, leukemia,
breast, ovary, rectum cancers etc.

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 Eye diseases like cataract and age related of
ratina, maculopathy.
 Ageing process.
 Diabetes.
 Skin lesions
 Immunodepression.
 Liver disease, pancreatitis.
 AIDS.
 Infertility.
PHYTOMEDICINE AS ANTIOXIDANT
Human body system is enriched with natural antioxidants
and can prevent the onset as well as treat diseases caused
and/or fostered due to free-radical mediated oxidative
stress. Human also takes antioxidants through diet. In
foods, antioxidants found in small quantities but capable to
prevent or greatly retard the oxidation of easily oxidizable
materials
27
.
Recent researches have shown that the antioxidants of
plant origin with free-radical scavenging properties could
have great importance as therapeutic agents in several
diseases caused due to oxidative stress
42
. Plant extracts
and phytoconstituents found effective as radical
scavengers and inhibitors of lipid peroxidation
43,44
. Many
synthetic antioxidant compounds have shown toxic and/or
mutagenic effects, which have stimulated the interest of
many investigators to search natural antioxidant
45
.
Herbal medicine is still the mainstay of about 75-80% of
the world population, mainly in developing countries, for
primary health care because of better cultural
acceptability, better compatibility with the human body
and lesser side effects. The chemical constituents present
in the herbal medicine or plant are a part of the
physiological functions of living flora and hence they are
believed to have better compatibility with human body.
Natural products from plants are a rich resource used for
centuries to cure various ailments. The use of bioactive
plant-derived compounds is on the rise, because the main
preoccupation with the use of synthetic drugs is the side
effects which can be even more dangerous than the
diseases they claim to cure. In contrast, plant derived
medicines are based upon the premise that they contain
natural substances that can promote health and alleviate
illness and proved to be safe, better patient tolerance,
relatively less expensive and globally competitive. So, in
respect of the healing power of plants and a return to
natural remedies is an absolute requirement of our
time
41,42,46
.
Even synthetic drugs used to treat various disorders can
capable of produce free radical which leads oxidative
stress and caused tissue damage. For example, non
steroidal anti-inflammatory drugs (NSAIDs) are used
widely in the treatment of pain, fever, inflammation,
rheumatic and cardiovascular disease but chronic
administration of those drugs leads the generation of free
radicals which may results gastric erosions, gastric or
duodenal ulceration and severe complications such as
gastrointestinal hemorrhage and perforation
46
.
The use of phytoconstituents as drug therapy to scavenge
free radicals and to treat disorders leads due to oxidative
stress has proved to be clinically effective and relatively
less toxic than the existing drugs. Therefore it is demand
of time to uses drugs from plant sources or
phytoconstituents to prevent and/or treat oxidative stress.
Table 1 listed different phytochemicals having antioxidant
property and Table 2 listed some plants producing
antioxidant activity in vitro and in vivo.
CONCLUSION
Currently there has been an increased interest globally to
identify antioxidant compounds from plant sources which
are pharmacologically potent and have low or no side
effects for use in protective medicine and the food
industry. Modern civilization, use of different chemicals,
pesticides, pollutant, smoking and alcohol intake and even
some of synthetic medicine increases the chance of disease
due to free radicals. Plants produces large amount of
antioxidants to prevent the oxidative stress, they represent
a potential source of new compounds with antioxidant
activity. More or less the free radicals plays a role in
health of modern era and the diseases caused from free
radical are becoming a part of normal life. Increasing
knowledge in antioxidant phytoconstituents and include
them in daily uses and diet can give sufficient support to
human body to fight those diseases. Phytoconstituents and
herbal medicine are also important to manage pathological
conditions of those diseases caused by free radicals.
Explore the antioxidant principles from natural resources;
identification and isolation of those phytoconstituents are
simultaneously presenting enormous scope for their better
therapeutic application for treatment of human disease.
Therefore it is time for us, to explore and identify our
traditional therapeutic knowledge and plant sources and
interpret it according to the recent advancements to fight
against oxidative stress, in order to give it a deserving
place.

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Table 1: Phytoconstituents with antioxidant activity
47-66
Phytoconstituents Example
Alkaloids Alkaloid extract of Fumaria capreolata and Fumaria bastardii contain protopine, cryptonine,
stylopine, fumariline, phtalidiisoquinoline, fumaritine, fumarafne and
dehydrobenzophenanthridine possess antioxidant activity.
Carotenes and
xanthophylls
Antioxidant activity of astaxanthine, α and β carotene, lutein, lycopene, zeaxanthin,
canthaxanthin were investigated.
Volatile and essential oil Essential oil (e.g.: α-terpinene, δ-3-carene, myrcene, α-pinene, p-cymene, β-phellandrene,
citronellol, trans-geraniol, α-copaene, agarospirol, globulol) isolated from Citrus reticulate
and Pelargonium graveolens having antioxidant activity.
Anthocyanins Cyanidin-3-O-β-glucopyranoside isolated from Chrysophyllum cainito, Eugenia uniflora,
Myrciaria cauliflora and delphinidin-3-O-β-glucopyranoside was identified from Eugenia
uniflora possess antioxidant activity.
Isoflavones Isoflavones one of the important types of flavonoids having antioxidant activity.
Flavan-3-ols Catechins posses antioxidant activity found in different plant like green tea.
Flavones Apigenin having antioxidant potential found in Thunbergia laurifolia
Flavonols Quercetin and isorhamnetin isolated from Haplopappus multifolius possess antioxidant
activity.
Flavanones Naringenin, a major flavanone constituent isolated from Citrus junos possess antioxidant
activities.
Coumarins Coumarins like hernianin, O-prenyl-umbelliferone, prenyletin, haplopinol isolated from
Haplopappus multifolius possess antioxidant activity
Stilbenes Cajaninstilbene acid from Cajanus cajan have similar antioxidant activity like the natural
antioxidant resveratrol.
Lignans Lignans from Myristica fragrans having antioxidant potential.
Lignins Lignins are complex phenolic polymers occurring in higher plant tissues possess antioxidant
activity. Example of lignins secoisolariciresinol diglycoside.
Phenolic Acids Phenolic acid possess antioxidant activity. Example of phenolic acid gallic acid, ellagic acid,
p-coumaric acid, ferulic acid, vanillic acid, protocatechuic acid
Triterpenoid saponins Extract of Salvia macrochlamys contain terpenoids like monogynol A, 3β-acetylmonogynol
A, 3β-acetyl,22β-hydroxymonogynol A, 3β-acetyl,21β,22β-dihydroxymonogynol A and
extract possess antioxidant activity.
Phytosterols Antioxidant activity of beta-sitosterol found in Morinda citrifolia investigated.
Tannins Tannins like ellagitannins and propelargonidin isolated from Syzygium cumini fruit showed
antioxidant effect.
Hydroxycinnamic acids
Hydroxycinnamic acid derivatives like caffeic acid, chlorogenic acid, sinapic acid, ferulic
acid and p-coumaric acid are widely distributed in plants important for their antioxidants.
Flavonoids Flavonoid glucosides like apigenin-7-O-β-glucopyranoside, luteolin-7-O-β-glucopyranoside,
luteolin-3'-O-β-glucopyranoside and chrysoeriol-7-O-β-glucopyranoside are isolated aerial
parts of Verbascum salviifolium possess antioxidant activity.
Flavonoids such as myricetin, quercetin, rutin, catechin, kaempferol, fisetin and naringenin
also important for their antioxidant property.

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Table 2: List of some plants having antioxidant properties
35,43, 67-92
Plant Name Family Part Used Method used for antioxidant study
Achyranthes aspera Amaranthaceae Leaves Antioxidant activity by lipid peroxidation method.
Acorus calamus Acoraceae Rhizome In vitro DPPH, TBA, FTC method.
Adiantum capillus-
veneris
Adiantaceae Whole plant In vitro DPPH free radical scavenging activity method.
Aegle marmelos Rutaceae Leaves
GST, GSH, MDA determination in diabetic and drug treated animals.
Albizia amara Mimosaceae Leaves Antioxidant activity by lipid peroxidation method.
Albizzia lebbeck Mimosaceae Leaves SOD, GPx, GST, CAT, GSH, TBARS, CD estimation in diabetic and drug
treated rat.
Aphanamixis
polystachya
Meliaceae Bark In vitro methods like superoxide anion scavenging activity, DPPH, ABTS,
FRAP method and assay of MDA, GSH after oxidative stress was induced
by Freund’s Complete Adjuvant.
Aquilaria malaccensis Thymelaeaceae Leaves In vitro DPPH method.
Bauhinia divaricata Caesalpiniaceae Leaf and stem In vitro DPPH method.
Bougainvillea
apectabilis
Nyctaginaceae Leaf and stem In vitro DPPH method.
Cassia auriculata Caesalpiniaceae Leaves Antioxidant activity by lipid peroxidation method.
Cassia fistula Caesalpinaceae Leaves In vitro DPPH, nitric oxide and hydroxyl radical scavenging activity
method and CCl
4
induced lipid peroxidation.
Centella asiatica Apiaceae Whole plant In vitro DPPH assay method.
Clerodendrum serratum Verbenaceae Root In vitro DPPH, FRAP, hydrogen peroxide scavenging method.
Curculigo orchioides Amaryllidaceae
Rhizome In vivo estimation of TBARS, SOD, CAT, GSH, GPx, GST, CD, GR in
CCl
4
induced hepatotoxicity.
Cydonia vulgaris Rosaceae Leaves Antioxidant activity was determined by thiocyanate and reducing power
method.
Cyperus rotundus Cyperaceae Rhizome
In vitro methods like superoxide anion scavenging, hydroxyl radical
scavenging, nitric oxide scavenging, metal chelating activity, reducing
power assay, lipid peroxidation inhibition assay.
Datura stramonium Solonaceae Leaves Antioxidant activity by lipid peroxidation method.
Equisetum maximum Equisetaceae Whole plant In vitro DPPH free radical scavenging activity method.
Ficus deltoidea Moraceae Leaves In vitro method like reduction power of iron, superoxide scavenging,
xanthine oxidase, nitric oxide scavenging and LPO method.
Hemidesmus indicus Asclepiadaceae Stem In vitro DPPH, TBA, FTC method.
Holarrhena
Antidysenterica
Apocynaceae Bark In vitro DPPH, TBA, FTC method.
Ichnocarpus frutesecens
Apocynaceae Whole plant SOD, CAT, GSH, TBARS estimation in paracetamol induced liver
damage.
Inonotus obliquus Hymenochaetaceae Whole
mushroom
Antioxidant activity by DPPH, superoxide and peroxyl radicals
scavenging method.
Lippia Alba Vebenaceae Leaves In vitro reducing power ability and DPPH method.
Mellilotus officinalis Fabaceae Whole plant In vitro DPPH free radical scavenging activity method.
Morinda lucida Rubiaceae Bark In vitro reducing power ability and antioxidant property determined by
using β-carotene.
Phyllanthus emblica Phyllanthaceae Fruit Determination of antioxidant activity by cyclic voltammetry, lipid
peroxidation and SOD determination method.
Plantago major
Plantaginaceae Whole plant In vitro DPPH free radical scavenging activity method.
Plumbago zeylanica Plumbaginaceae Root In vitro DPPH, TBA, FTC method.
Psidium guajava Myrtoideae Fruit Total phenolic content and FRAP estimation were carried out.
Rhizophora mangle Rhizophoraceae Bark Determination of SOD, CAT, GPx and lipid peroxidation in NSAIDs
induced gastric ulcer.
Rosa canina Rosaceae Ripe fruit Bleomycin iron dependent DNA damage, lipid oxidation, prorein
oxidation and carbohydrate damage method.
Rubia Cordifolia Rubiaceae Root Estimation of LPO, GSH, SOD, CAT in ethanol induced oxidative stress.
Sideritis raeseri Lamiaceae Aerial parts Antioxidant activity by Co(II) EDTA-induced luminol chemiluminescence
and DPPH scavenging activity method.
Sutherlandia frutescens Fabaceae Whole plant Superoxide and hydrogen peroxide scavenging activities of the plant
investigated.
Trichosanthes
tricuspidata
Cucurbitaceae Root
Estimation of SOD, CAT, GPx, LPO in sildenafil induced migraine.
Urtica dioica Urticaceae Whole plant In vitro DPPH free radical scavenging activity method.
Utleria salicifolia Periplocaceae Rhizome Determination of SOD, CAT in ulcer induced animals.
(DPPH – 1,1-diphenyl-2-picryl hydrazyl radical; GST – glutathione-S-transferase; GSH – glutathione; MDA –
malondialdehyde; ABTS – Free-radical scavenging activity; FRAP – Ferric Reducing Antioxidant Power; TBARS –
Thiobarbituric acid reactive substances; CD –Diene conjugates; CAT – catalase; GPx – Glutathione peroxidase; GR –
Glutathione reductase; LPO – Lipid peroxidation; FTC – Ferric thiocyanate method; TBA – Thiobarbituric acid method)

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International Journal of Pharmaceutical Sciences Review and Research Page 97
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