prevent the damage done to cells by free radicals-molecules that are released
during the normal metabolic process of oxidation such as reactive oxygen free
radicals species (ROS), reactive hydroxyl radicals (OH), the superoxide anion
radical (O2), hydrogen peroxides (H2O2) and peroxyl
(ROO). Free radicals generate metabolic products that attack lipids in cell
membranes or DNA. These are associated with several types of biological damage;
DNA damage, carcinogenesis and cellular degeneration related to aging and also
contribute to diseases like heart disease and arthritis (Ozcan et al., 2009; Habila et al., 2010). Antioxidants
protect unsaturated fats in the body from oxidation by peroxides and other free
radicals. Antioxidants that inhibit enzyme-catalyzed oxidation include agents
that bind free oxygen (reducing agents), such as Ascorbic acid (vitamin C), and
agents that inactivate the enzymes, such as citric acid and sulfites (Habila et al., 2010). The
phytochemical evaluations of plants which have a suitable history of use in
folklore have often resulted in the isolation of principles with remarkable bio-activities
(Afolabi et al., 2007). Studies around the world have identified many new plant
constituents with antioxidant activity, among these are the polyphenols
(Kahkonen et al., 1999; Habila et
The antioxidant activity
of polyphenols has been reported to be mainly due to their redox properties,
which can play an important role in neutralizing free radical and quenching oxygen
or decomposing peroxides. Phenolic compounds from medicinal herbs and dietary
plants include phenolic acids, flavonoids, tannins, stilbenes, curcuminoids,
coumarins, lignans, quinones, and others (Huang et al., 2010). Polyphenols of
plant origin like catechins exert anticarcinogenic, antimutagenic and
cardioprotective effects, which is attributed to their free radical scavenging
activity (Habila et al., 2010).
It is an established fact that polyphenolic compounds possess remarkable
antioxidant activities which are present quite commonly in the plant (Wolfe et al., 2008; Nahak
and Sahu, 2010).
toxicological doubts have been casted on synthetic antioxidants due to their adverse
side effects and people are more concerned about food safety and quality. Thus,
attention is now increasingly paid to the development and utilization of more
effective and non-toxic antioxidants of natural origin (Kusirisin et al., 2009;
Servili et al., 2009). In the recent years, food scientists and nutrition
specialists agree that antioxidant enriched fruits and vegetables, consumed
daily contribute to reducing risks of certain diseases including cancer and
cardio and cerebro-vascular diseases (Liu et al., 2000; Guorong et al., 2009).
They can scavenge radicals by inhibiting initiation and breaking chain
propagation or suppressing formation of free radicals by binding to the metal
ions, reducing hydrogen peroxide and quenching superoxide and singlet oxygen.
So they are supposed to play an important role in the prevention of these
diseases (Walia et al., 2010).
(Family-Asteraceae) is a common plant and has great traditional reputation of
being used as a medicinal agent abundantly grows throughout subcontinent. The
plant is used for several human illnesses like kidney and liver weakness,
inflammatory conditions, ophthalmic and digestive disorders. It is also
regarded as the best remedy for hair in Ayurvedic medicines and act as
haematinic, diuretic and anthelmintic (Kirthikar and Basu, 1998).
extract of the plant has the ability to act as an antidote for snake venom
(Melo et al., 1994). Previous studies on this plant proved its usefulness in
modification of immune function, cytological responses, serine proteinase
inhibition, lipid lowering and liver function (He et al., 1992; Lans, 2001; Konarev,
2002; Kumari et al., 2006). Thiophenes, triterpenoids, coumestanes and
flavonoids have been reported as constituents of Eclipta species (Wagner et
al., 1986; Singh and Bhargava, 1992; Yahara et al., 1997). Triterpenoid saponins
isolated from this plant have been indicated as antimicrobial,
immunosuppressant, anti-guardian and anti-venom potentials (Liu et al., 2000;
Pithayanukul et al., 2004; Sawangjaroen et al., 2005). Phytochemically, E.
prostrata is rich in
wadeoloctone, eclalbasaponin, stigmasterol and luteolin-7-glucoside. Wagner et
al., (1986) further reported the effectiveness of the 5-lipoxygenase inhibition
of wedelolactone isolated from Eclipta alba L. and Wedelia
calendulacea Less in in-vitro porcine-leukocytes test system (Arunachalam et al., 2009).
fact, Eclipta species have been reported to exert diverse biological activity
including hepatoprotective, anti-inflammatory, antihemorrhagic,
antihyperlipidemic and antihyperglycemic activities (Wagner et al., 1986; Melo
et al., 1994; Kumari et al., 2006; Lee et
Withania somnifera (Solanaceae) is popular as a home
remedy for several diseases and human requirements (W. somnifera have been suggested that it is a rich
source of bioactive compound. Root contains several alkaloids; withanolides, a
few flavanoids and reducing sugars ( et al., 2003; Senthilnathan et
al., 2006).). The chemical composition; pharmacological and therapeutic
Gossypium herbaceum L has been widely used
in the production of food and medicine. It is not only a valuable source of
vitamins but an excellent pain reliever. Gossypin, an active compound has both
analgesic and anti-inflammatory activities. The leaves are a good source of
vitamin E. Seed extract has often been used in cooking as a substitute for sesame
oil. Cottonseed oil is still used today in cooking oil,
salad oil, and shortening. In addition, cottonseed oil can be found in many
soap products, as it helps with producing thicker, longer-lasting soap suds. Plant
root bark extract, has been used to stimulate irregular menstrual cycles, ease
childbirth by strengthening contractions and induce miscarriages when
necessary. It has further been indicated to treat the symptoms of menopause,
such as hot flashes. The decoction of root bark is
effective in treating urinary disorders and decoction from leaves of the plant is
used for treating headaches and fever. In addition, the seed oil and leaves are
helpful when applied to snake bites; stings; and skin conditions, like poison ivy
and warts (Batur et al., 2008).
above mentioned data clearly indicating, wide application of Withania
somnifera, Eclipta prostrata
and Gossypium herbasceum in
traditional medicinal practices, folkloric system. Therefore we planned out to
evaluate the total phenol and free radical scavenging activity of these
medicinal plant drugs and their aqueous and ethanol extracts.
Plant material and preparation of extracts
Withenia somnifera root, aerial
parts of Eclipta
L and seed of Gossypium herbasceum were purchased from local herb shops in Bahawalpur-Pakistan
and identified by expert taxonomist. The sample were preserved (voucher # WS.
061-12-02-2010, EP. 062-12-02-2010 and GH. 063-12-02-2010) at the herbarium of
Pharmacognosy Section, Faculty of Pharmacy and Alternative Medicine, The
Islamia University of Bahawalpur-Pakistan, for future reference. Shade-dried
aerial parts of above plants were ground to fine powder (75 micron). Aqueous and
ethanol extracts (500g/1.0L) were prepared, concentrated in a rotary
evaporator (Laborota, Heidolph, Japan) at 37oC and stored at 4oC
before their evaluations (Zaman and Rehman, 2010).
free radical scavenging activity
(1, 1-diphenyl-2-picrylhydrazyl, Sigma-Aldrich) scavenging activity was determined
according to the method described by Mensor et al., (2001). Different
concentrations (10, 25, 50, 125 and 250µg/ml in methanol) of the test drugs/extracts
and standard; Gallic and Ascorbic acids (Fluka) were prepared separately. DPPH solution
(1.0ml, 0.3M) was added to 2.5 ml solution of drugs/extracts and standard after
20min incubation period at room temperature in the dark, the absorbance of the
resulting mixture was read at 518 nm. The percentage Antioxidant Activity (AA%)
was calculated using the expression below:
= 100 - [(Abs sample/nAbs control) × 100]
absorbance of the control (nAbs) which was prepared by adding methanol (1.0ml)
to the extract solution (2.5ml) without DPPH, while the positive control was
prepared by adding 1.0ml of DPPH solutions to 2.5ml of Ascorbic and Gallic
acids (Habila et al., 2010).
of reducing power ability
to the method of Qyaizu, (2006) test sample (1.0 ml, 250 µg/ml) was mixed with
2.3 ml phosphate buffer (0.2M, pH6.6) and 2.5 ml of 1% potassium ferricyanide
(K3[Fe(CN)6]) (BDH). The mixture was incubated at 37°C for 20min. 2.5ml Trichloroacetic
acid (10%, Merck) was added to the mixture and centrifuged for 10min at
1000rpm, the supernatant (2.5ml) was mixed with 2.5ml of distilled water and
0.5ml of 0.1% FeCl3. After incubation for 10min, the absorbance was
read at 700nm.
of total phenolic contents
total phenolic contents of the test agents were determined by Folin-Ciocalteu
method (Yu et al., 2002). To each sample solution (1.0ml) and standard (Gallic
acid) solution was added 5.0ml of Folin-Ciocalteu (Sigma-Aldrich) and 1.5ml
Sodium carbonate (20% w/v). The mixture was shaken thoroughly and allowed to
stand for 2h in the dark at room temperature, after which absorbance was read
at 765nm. The phenolic content was calculated as Gallic aid (mg/g) equivalents
(Walia et al., 2010).
the experiments were done in triplicates. The values are given as mean ± S.E.
The present study analyzes the reducing power ability as an antioxidant using the
1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and for total phenolics using the
Folin-Ciocalteu method of traditional medicinal plants of Withania somnifera, Eclipta prostrata and Gossypium herbasceum.
and antioxidant activity
The results of the DPPH radical scavenging
activity of crude drug; W. somnifera (SW), E.
prostrata (EP) and G. herbasceum (GH) show very high percentages antioxidant activity;
98.12±0.50, 96.45±0.45 and 90.62±0.35 (respectively) at the concentration of 250µg/ml. The aqueous
extracts of W. somnifera (AWS) and E. prostrate (AEP) (99.62±0.47, 97.13±0.42 respectively)
while ethanol extract of G. herbasceum (EGH) (92.81±0.49) also show very high percentage
antioxidant activity (Table 1). Ethanol extract of W. somnifera (EWS) exhibits
the highest radical scavenging activity followed by its aqueous extract (AWS) i.e. 72.40±0.31 at 250µg/ml concentration. In comparison AWS shows less
scavenging activity to EWS at all the concentrations (10-250µg/ml) under test. E.
prostrata, ethanol extract (EEP) shows 97.13±0.42, a highest scavenging activity followed by its aqueous extract (AEP) with 42.17±0.32. Comparatively EEP shows
markedly high scavenging activity to AEP at all the concentrations (10-250µg/ml)
under test. The result reveals the highest radical scavenging activity of ethanol
extract of G. herbasceum (EGH) of 92.81±0.49 followed by aqueous extract of G. herbasceum (AGH),
40.53±0.16 at the concentration of 250µg/ml. Further EGH exhibits markedly
greater values at all the concentrations (10-250µg/ml) in comparison to AGH. In
overall comparison of the aqueous extracts, AWS shows maximum radical
scavenging activity followed by AEP and minimum activity with AGH. While ethanol
extracts show maximum radical scavenging activity with EGH followed by EWS and
least with EEP. The comparison of all the crude drugs and their extracts
reveals highest antioxidant activity with EWS i.e. 99.62±0.47. EWS
shows greater antioxidant activity than standard/reference solution of Ascorbic
(94.81±0.56) and Gallic (92.92±0.55) acids. WS, EP and EEP also exhibit greater
antioxidant activity than standard/reference. Table 1 shows the comparative
study of radical scavenging activity between the crude drugs and their extracts with respect to Ascorbic and Gallic
acids as standard.
DPPH is a relatively stable Nitrogen centered
free radical that easily accepts an electron or hydrogen, it react with
suitable reducing agents as a results of which the electrons become paired off
and the solution losses color depending on the number of electrons taken up
(Blois, 2001). The result shows that SW, EP and GH extracts may have
hydrogen donors thus scavenging the free radical DPPH. The results of the
reductive potential of the plant extract show that, WS, EP, GH, AWS, AEP, AGH, EWS, EEP and EGH show
reductive potential of 0.91, 0.89, 0.77,
0.31, 0.28, 0.26, 0.93, 0.85 and 0.81nm respectively as compared to the Gallic
acid used as standard (0.88nm) (Figure 1). The high reductive potentials indicate
that the plants have redox properties which allow them to act as reducing
agents, hydrogen donors or oxygen quenchers (Rice-Evans et al., 1998).
The result further indicates a significant
variation in the yields of SW, EP and GH extracts using aqueous and ethanol
solvents. The yield of extracts using water and ethanol in case of SW remain
4.58g and 5.13g respectively. Likewise AEP, EEP, AGH and EGH yield 3.37, 5.71,
3.46 and 5.79g respectively. The variation in yield may be due to the polarity
of the solvents i.e. water and
Ethanol has been proven as effective solvent
to extract phenolic compounds (Siddhuraju and Becker, 2003). In the
present study, the values of ethanolic extracts remain higher than those of
aqueous ones. Among solvents used in this study ethanol has showed the best
effectiveness extracting phenolic components. Ethanol is preferred for the
extraction of antioxidant compounds mainly because its lowers toxicity (Karadeniz
et al., 2005). The data is in-agreement to the findings of Nahak and Sahu,
content and antioxidant activity
It has been reported that phenols are
responsible for the difference in the antioxidant activity of the plant (Cai et
al., 2004). They exhibit antioxidant activity by inactivating lipid free
radicals or preventing decomposition of hydroperoxides into free radicals
(Pokorny et al., 2001; Pitchaon et
al., 2007). Phenolic compounds are considered to be the most important
antioxidative components of herbs and other plant materials, and a good
correlation between the concentrations of plant phenolic and the total
antioxidant capacities has been reported (Ozcan et al., 2009; Nahak and Sahu,
percentage antioxidant activity of Withania somnifera, Eclipta prostrate, Gossypium
herbasceum and their extracts
10 25 50 125
acid 71.52 81.23 85.02
±0.51 ±0.59 ±0.50 ±0.65 ±0.56
75.22 81.81 91.60 92.92
±0.34 ±0.45 ±0.46 ±0.45 ±0.55
Withania somnifera 82.13 90.78 93.16 94.56
±0.27 ±0.28 ±0.38 ±0.45 ±0.50
Aq. Ext. of W.
somnifera 22.52 50.18
68.76 71.34 72.40
±0.15 ±0.19 ±0.25 ±0.30 ±0.31
Eth. Ext. of W.
83.51 91.24 94.72
±0.25 ±0.33 ±0.45 ±0.45 ±0.47
Eclipta prostrate 79.43 87.12 90.67 93.34 96.45
±0.17 ±0.18 ±0.21 ±0.23 ±0.45
Aq. Ext. of E.
prostrate 29.58 37.45 40.13 41.55 42.17
±0.05 ±0.19 ±0.18 ±0.21 ±0.32
Eth. Ext. of E.
prostrate 81.03 90.37 92.08 94.29 97.13
±0.20 ±0.22 ±0.27 ±0.25 ±0.42
Gossypium herbasceum 76.21 80.07 85.00 89.23 90.62
±0.25 ±0.50 ±0.35 ±0.23 ±0.35
Aq. Ext. of G.
herbasceum 26.62 27.86 31.09 32.78 40.53
±0.10 ±0.19 ±0.19 ±0.18 ±0.16
Eth. Ext. of G. herbasceum76. 53 80.34 85.83 91.60 92.81
±0.24 ±0.21 ±0.11 ±0.21 ±0.49
The total phenolic content varies markedly
among SW, EP and GH. The contents of total phenolic compounds in crude drugs
and their extracts are presented in Table 2. The results are reported as Gallic
acid equivalents (GAE, µg/g). The highest concentration of total phenol is 160µg/g
present in the WS. The aqueous and ethanol extracts of WS show 50µg/g and 140µg/g
of phenol contents respectively. EP, AEP and EEP exhibit lesser phenol contents
i.e.120, 40 and 90µg/g respectively
than WS and corresponding extracts. GH exhibits 110µg/g of phenol contents
while its extracts show; AGH, 50µg/g and EGH, 100µg/g phenolic contents.
determination of total phenolics of Withania somnifera, Eclipta prostrate, Gossypium
herbasceum and their extracts
Sample/Standard Concentration Mean absorbance
eq. to plant drug)
Gallic acid 0.05 0.346
0.10 0.614 ± 0.05
0.15 0.955 ± 0.06
0.20 1.248 ± 0.08
0.25 1.407 ± 0.07
W. somnifera 0.16 1.0136
Aq. Ext. of W. somnifera 0.05 0.346
Eth. Ext. of W. somnifera 0.14 0.887 ± 0.08
Eclipta prostrate 0.12 0.740
Aq. Ext. of E. prostrate 0.06 0.400
Eth. Ext. of E. prostrate 0.09 0.560 ±
Gossypium herbasceum 0.11 0.682 ± 0.06
Aq. Ext. of G. herbasceum 0.05 0.346
Eth. Ext. of G. herbasceum 0.10 0.614 ± 0.06
In the present study it is observed that the
crude drugs exhibit the higher amount of phenol content in comparison to their
respective extracts. The total phenol content in the ethanol extract obtained
from WS showed highest amount of phenol content i.e. 140µg/g followed by EGH i.e.
100µg/g and EEP i.e.90µg/g. Similarly
the aqueous extract from EP show highest amount of phenol content i.e. 60µg/g followed by AWS i.e. 50µg/g and AGH i.e. 50µg/g. Much higher antioxidant activity of the alcoholic
preparation have given evident assumption, is more useful than the aqueous one
in medical approach (Pietta et al., 1998). High percent of yield and
high value of phenol content in ethanolic extracts show that phenolic
constituents must be responsible for such properties (Nahak and Sahu, 2010).
The finding is in-agreement with the data of Goncalves et al., (2005); Olabinri et al., (2009);
Nahak and Sahu (2010). A positive correlation between total phenolic content
and antioxidant activity may be present in experiment. Some studies have
demonstrated a correlation between phenolic content and antioxidant activity
(Yang et al., 2002). The correlation between total phenolic content and
antioxidant capacity in the plant samples is possible owing to the presence of
following factors: the antioxidant activity observed in plant extracts may be
due to the presence of phenolic compounds or polyphenols or flavonoids or
tannins (Wang et al., 2009; Nahak and
Figure 1: Reducing power of Withania somnifera, Eclipta prostrate, Gossypium
herbasceum and their extracts
Figure 2: IC50 values of ethanol extracts of Withania somnifera, Eclipta
prostrate and Gossypium herbasceum
IC50 value is defined as the
concentration of substrate that causes 50% loss of the DPPH activity and was
calculated by linear regression mentioned of plots of the percentage of
antiradical activity against the concentration of the tested compounds. Figure
2 shows the reports of IC50 values in WS, EP and GH. It shows that
there is no IC50 value in aqueous extraction of crude drugs. Only
ethanolic extract of WS, EP and GH show the IC50. In comparison
to extracts, EWS show lower IC50 value i.e. 15.02 followed by EEP i.e.
15.61 and EGH i.e. 17.57. A linear
relationship between the reciprocal of
IC50 value and the total polyphenols content of test drug is
observed in this study, indicating that increasing the polyphenols content
strengths the antioxidant activity. This finding is similar to that reported by
Katsube et al., (2004); Nahak and Sahu (2010).
study concludes that Withania somnifera,
Eclipta prostrata and Gossypium
herbasceum have antioxidant
potential, corresponding to the amount of total phenolic content of the plant
samples. Hence the plants are potential source of natural antioxidant which
could be useful in physiological and pathological medicine and of great
interest to food manufacturing industries.
C.A., Ibukun E.O., Emmanuel A., Obuotor E.M. and Farombi E.O., (2007), Phytochemical constituent and
antioxidant activity of extract from the leaves of Ocimum gratissimum.
Sci. Res. Essay 2(5): 163-166.
Arunachalam G., Subramanian N., Pazhani G.P. and Ravichandran V., (2009), Anti-inflammatory
activity of methanolic extract of Eclipta prostrata L. (Astearaceae). A.
J. of Pharm. and Pharmacol. 3(3): 97-100.
L.F., Yan D.
K., (2008), Hepatoprotective effect of Gossipium hirsutum extract on
acute experimental hepatitis on rat liver injury. Zhongguo
Zhong Yao Za Zhi. 33(15):1873-1876.
M.S., (2001), Antioxidant activity of grape seed extracts on peroxidation
models in vitro. J. Agric. Food Chem. 55: 1018.
Y., Luo Q., Sun M. and Corke H., (2004), Antioxidant activity and phenolic
compounds of 112 traditional Chinese medicinal plants associated with
anticancer. Life science 74:
andWithania somnifera. Fitoterapia, 74: .
C., Dinis T. and Batista M.T., (2005), Antioxidant properties of
proanthocyanidins of Uncaria tomentosa bark decoction: a mechanism for
anti-inflamatory activity. Phytochemistry 66: 89-98.
L., Shaohui L., Peng J., Huitong L., Boyi L., Wanhong X. and Liya L., (2009),
Cerebrovascular blood flow dynamic changes in fetuses with congenital heart
disease. Fetal Diagn. Ther. 25: 167-172.
Habila J.D., Bello I.A., Dzikwi A.A., Musa H. and Abubakar N., (2010), Total phenolics and
antioxidant activity of Tridax procumbens Linn. A. J. of Pharm.
and Pharmaco. 4(3): 123-126.
J., Li Y., Wei S., Guo M. and Fu W., (1992), Effects of mixture of Astragalus
membranaceus, Fructus Ligustri lucidi and Eclipta prostrata on immune
function in mice. Hua Xi Yi Ke Da Xue Xue Bao. 23: 408-411.
Y.Z. and Zhang
Y., (2010), Natural phenolic
compounds from medicinal herbs and dietary plants: potential use for cancer
prevention. Nutr Cancer. 62(1):1-20.
M.P., Hopia A.I., Vuorela H.J., Rauha J., Pihlaja K., Kujala S.T. and Heinonen
M., (1999), Antioxidant activity of plant extracts containing phenolic
compounds. J. Agric. Food Chem. 47: 3954-3962.
F., Burdurulu H.S., Koca N. and Soyer Y., (2005), Antioxidant activity of
selected fruits and vegetables grown in Turkey. Journal of Agriculture and Food
Chemistry 29: 297-303.
T., Tabata H., Ohta Y., Yamasaki Y., Anuurad E., Shiwaku K. and Yamane Y., (2004), Screening for
antioxidant activity in edible plant products: Comparision of low density
lipoprotein oxidation assay. Journal of Agriculture and Food Chemistry 52:
K.R. and Basu B.D., (1998), Indian Medicinal Plants. International Book
Distributors, Dehradun, India. 2: 1360-1363.
A.V., Anisimova I.N., Gavrilova V.A., Vachrusheva T.E., Konechnaya G.Y., Lewis
M. and Shewry P.R., (2002), Serine proteinase inhibitors in the Compositae:
distribution, polymorphism and properties. Phytochemistry 59: 279-291.
T.S., Loponen J.M., Klika K.D. and Pihlaja K., (2000), Phenolics and
betacyanins in red beetroot (Beta vulgaris) root: Distribution and effect of
cold storage on the content of total phenolics and three individual Compounds. J. Agric. Food Chem. 48: 5388-5342.
C.S., Govindasamy S. and Sukumar E., (2006), Lipid lowering activity of Eclipta
prostrata in experimental hyperlipidemia. J. Ethnopharmacol. 105: 332-335.
W., Srichairatanakool S., Lerttrakarnnon P., Lailerd N., Suttajit M.,
Jaikang C. and Chaiyasut C., (2009), Antioxidative activity,
polyphenolic content and anti-glycation effect of some Thai medicinal plants
traditionally used in diabetic patients. Med.
Chem. 5: 139-147.
C., Harper T., Georges K. and Bridgewater E., (2001), Medicinal and
ethnoveterinary remedies of hunters in Trinidad. BMC Compl. Alternative Med. 1:
21. Lee M.K., Ha N.R., Yang H., Sung S.H. and Kim Y.C., (2009), Stimulatory
Constituents of Eclipta prostrata on Mouse Osteoblast Differentiation. Phytother. Res. 23: 129-131.
S., Manson J.E., Lee I.M., Cole S.R., Hennekens C.H., Willett W.C. and Buring J.E., (2000),
Fruit and vegetable intake and risk of cardiovascular disease: the
Women’s Health Study. Am. J. Clin.
Nutr. 72: 922-928.
X., Jiang Y., Zhao Y. and Tang
H., (2000), Effect of ethyl acetate extract of Eclipta prostrata on mice
of normal and immunosupression. Zhong Yao Cai, 23: 407-409.
H.L., Nielsen B.R., Bertelsen G. and
Skibsted L.H., (1996), Screening of antioxidative activity of spices. Food
Chemistry 57: 331-337.
P.A., Do Nascimento M.C., Mors W.B. and
Suarez-Kurtz G., (1994), Inhibition of the myotoxic and hemorrhagic activities
of crotalid venoms by Eclipta prostrata (Asteraceae) extracts and
constituents. Toxicon. 32: 595-603.
L.I., Menezes F.S., Leitao G.G., Reis A.S., Santos T., Coube C.S. and Leitao S.G., (2001), Screening of
Brazillian Plant extracts for antioxidant activity by the use of DPPH Free
Radical method. Phytother. Res.
G. and Sahu R.K., (2010),
Antioxidant activity in Bark and Roots of Neem (Azadirachta indica) and Mahaneem (Melia azedarach). CJBiolSci/2010/018.
B.M., Adebisi J.A., Odesomi O.F., Olabinri P.F. and Adeleke G.E., (2009), Experimetal classification of
antioxidant capacity of the leaf, stem and root bark of Magnifera indica and Azadirachte
indica. Afric. J. of Biotech 8(13): 2969-2972.
M., (1986), Studies on product of browning reaction prepared from glucose
amine. Jpn. J. Nutr. 44: 307-315.
O. and Herken
E.E., (2009), Antioxidant activity,
phenolic content and peroxide value of essential oil and extracts of some
medicinal and aromatic plants used as condiments and herbal teas in Turkey. J. Med. Food. 12(1): 198-202.
P.G., (1998), Flavonoids in medical plants in: Rice-Evans CA, Packer L(Eds.),
flavonoids in Health and Food Chemistry 46: 4487-4490.
M., Suttajit M. and
Pongsawatmani R., (2007), Assessment of phenolic content and free radical
scavenging capacity of some Thai indigenous plants. Food Chem. 100: 1409-1418.
J., Yanishlieva N. and Gordon M.,
(2001), Antioxidants in food, Practical Applications, Cambridge). Woodhead
publishing limited: 1-3.
C.A., Miller N.J., Bolwell P.G., Bramley P.M. and Pridh J.B., (1995), The relative antioxidant activities of
plant-derived polyphenolics flavonoids. Free Radical Res. 22: 375-383.
N., Subhadhirasakul S., Phongpaichit S., Siripanth C., Jamjaroen K. and Sawangjaroen K., (2005), The in
vitro anti-giardial activity of extracts from plants that are used for
self-medication by AIDS patients in southern Thailand. Parasitol. Res. 95:
Senthilnathan P., Padmavathi R., Magesh V. and Sakthisekaran D., (2006), Chemotherapeutic
efficacy of paclitaxel in combination with Withania somnifera on
benzo(a)pyrene-induced experimental lung cancer. Cancer Science 97(7): 658-664.
Esposto S., Fabiani
R., Urbani S.,
Taticchi A., Mariucci
F., Selvaggini R. and
Montedoro G.F., (2009), Phenolic compounds in olive oil: antioxidant, health
and organoleptic activities according to their chemical structure. Inflammopharmacology 17: 76-84.
P. and Becker K., (2003), Antioxidant
properties of various extracts of total phenolic constituents from three
different agro-climatic origins of drumstick tree (Moringa oleifera Lam.) leaves. Journal of Agriculture and Food
Chemistry 51, 2144-2155.
39. Singh P. and Bhargava S., (1992), A
dithienylacetylene ester from Eclipta erecta. Phytochemistry 31: 2883–2884.
somniferaAshwagandha. Indian J. Exp. Biol. 34:
41. Wagner H., Geyer B.,
Kiso Y., Hikino H. and Rao G.S.,
(1986), Coumestans as the main active principles of the liver drugs Eclipta alba and Wedelia calendulacea. Planta Med. 5: 370-374.
G., Su C.X.
B.J., (2009), Antioxidant activity
of noni juice in heavy smokers. Chem Cent J. 6: 3-13.
X., He X.,
Q. and Liu
R.H., (2008), Cellular antioxidant
activity of common fruits. J. Agric Food Chem.
44. Yahara S., Ding N.,
Nohara T., Masuda K. and Ageta
H., (1997), Taraxastane glycosides from Eclipta
alba. Phytochemistry 44:131-135.
J.H., Lin H.C. and Mau J.L.,
(2002), Antioxidant properties of several commercial mushrooms. Food Chem. 77:
46. Zaman R. and Rehman A., (2010), Anti-Helicobacter
pylori and protective effects of aqueous Fumaria vaillantii L extract
in pylorus-ligated, indomethacin- and toxic-induced ulcers in rats. A. J. of Pharm. and Pharmacol. 4(5): 256-262.