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Effect of season and production location on antioxidant activity of Moringa oleifera leaves grown in Pakistan

  • University of Education, Lahore Jauharabad Campus

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Antioxidant activity (AA) of methanolic extracts from Moringa oleifera leaves, as function of seasons and agroclimatic locations, was investigated. Total phenolic content (TPC), total flavonoid content (TFC), ascorbic acid (AAcid) content , reducing power, AA in linoleic acid system and scavenging power of superoxide anion radical were taken as parameters for evaluation of AA. Significant differences were observed in the AA of the extracts from different locations and seasons. Generally, samples from Mardaan exhibited highest AA followed by Balakot, Chakwal, Jamshoro, and Nawabshah. Overall antioxidant efficacy was greater in December or March depending upon location, and least in June. Antioxidant potential of M. oleifera leaves from Pakistan was quite comparable or higher than literature values for M. oleifera from other countries and some other potent antioxidants. This work shows that season and agroclimatic locations have profound effect on the AA of M. oleifera leaves.
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Journal of Food Composition and Analysis 19 (2006) 544– 551
Original Article
Effect of season and production location on antioxidant activity of
Moringa oleifera leaves grown in Pakistan
Shahid Iqbal
, M.I. Bhanger
Free Radical Research Laboratory, National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro-76080, Pakistan
Received 28 September 2004; received in revised form 9 May 2005; accepted 12 May 2005
Antioxidant activity (AA) of methanolic extracts from Moringa oleifera leaves, as function of seasons and agroclimatic locations,
was investigated. Total phenolic content (TPC), total flavonoid content (TFC), ascorbic acid (AAcid) content , reducing power, AA
in linoleic acid system and scavenging power of superoxide anion radical were taken as parameters for evaluation of AA. Significant
differences were observed in the AA of the extracts from different locations and seasons. Generally, samples from Mardaan
exhibited highest AA followed by Balakot, Chakwal, Jamshoro, and Nawabshah. Overall antioxidant efficacy was greater in
December or March depending upon location, and least in June. Antioxidant potential of M. oleifera leaves from Pakistan was quite
comparable or higher than literature values for M. oleifera from other countries and some other potent antioxidants. This work
shows that season and agroclimatic locations have profound effect on the AA of M. oleifera leaves.
r2005 Elsevier Inc. All rights reserved.
Keywords: Moringa leaves; Antioxidant activity; Agroclimatic locations; Seasons; Total phenolics; Reducing power
1. Introduction
Epidemiological studies have shown that foods rich in
antioxidants provide protection against degenerative
diseases including cancer, coronary heart diseases, and
Alzheimer’s disease (Pezzuto and Park, 2002;Razali
et al., 1997;Ames et al., 1993). Therefore, it is
considered important to increase intake of antioxidants
from dietary sources (Soong and Barlow, 2004).
Previously, synthetic antioxidants like BHA and BHT
have been in use as food additives but recent reports
have expressed safety concerns about their usage (Sun
et al., 2005) and natural antioxidant have become the
focus of intense interest (Wilson, 1999). The commercial
development of plants as sources of antioxidants to
enhance health and food preservation is the focus of
current interest (Rice-Evans et al., 1997). Plants are rich
sources for natural antioxidants, the best known are
tocopherols, flavonoids, vitamin C, and different phe-
nolic compounds (Laandrault et al., 2001). Many herbs,
fruits (Ramarathnam et al., 1995), vegetables (Ismail
et al., 2004), spices, and legumes have been exploited as
sources of antioxidants.
Moringa oleifera, Lam. (Moringaceae) is grown
world-wide in the tropics and sub-tropics of Asia and
Africa (Booth and Wickens, 1988) and is one of the 14
species of genus Moringa, which are native to India,
Africa, Arabia, Southeast Asia, the Pacific and Car-
ibbean islands, and South America (Sengupta and
Gupta, 1970). The species are drought resistant and
tolerate a wide range of soil and rainfall conditions.
Various varieties of M. oleifera have been developed to
meet the tastes of local populations (Rajan, 1986).
Two species of Moringa, i.e., M. concanensis and
M. oleifera are present in Pakistan, but no compiled
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Corresponding author. Tel.: +92 333 2656248/92 300 3079516;
fax: +92 221 771560.
E-mail addresses:, (S. Iqbal).
information about these varieties is present. M. con-
canensis is found rarely, but M. oleifera is cultivated
widely throughout the temperate regions of the country
(Qaiser, 1973).
Different parts of this plant, i.e., leaves, flowers, roots
and fruits, have traditionally been used for dietary
purposes as vegetables (Qaiser, 1973;Siddhuraju and
Becker, 2003). Fresh leaves have been used by Indian
inhabitants for the preparation of cow and buffalo ghee
from butterfat. Its leaves are a valuable source of
vitamins A and C, they promote digestion, and they are
used in catarrhal afflictions and for treating wounds (Pal
et al., 1995). The leaves mixed with chicken soup are
used by Philippine women to enhance breast milk
production (Chopra et al., 1956). Leaves of M. oleifera
have been reported to contain flavonoid pigments such
as kaempferol, rhamnetin, isoquercitrin, and kaempfer-
itrin (Nair and Subramanian, 1962). Recently, from our
laboratory, Anwar and Bhanger (2003) exploited M.
oleifera as a non-conventional source of oil with
significantly high oxidative stability, revealing the
presence of natural antioxidants. Lalas and Tsaknis
(2002), from Greece reported the oxidative stability of
seed oil and isolated components liable for antioxidant
activity (AA) from Malawi variety. A report on
antioxidant properties of M. oleifera leaves from
different countries, suggesting wide variation, has been
exploited by Siddhuraju and Becker (2003). Recently,
Anwar et al. (2005) have reported significant variations
in oil content of Moringa seeds as function of agrocli-
matic locations.
However, no study has been conducted so far dealing
with the AA and composition of M. oleifera leaves
indigenous to Pakistan. No data describe the effect
of agroclimatic location and season on the antioxidant
potential of M. oleifera leaves. The ultimate objective
of the present study was to investigate AA and
composition of M. oleifera leaves, and the effects
of agroclimatic conditions and seasons within Pakistan
on AA.
2. Materials and methods
2.1. Materials
Fresh leaves of M. oleifera were collected in the
months of December, March, June, and September from
five different areas of Pakistan: Balakot, Chakwal,
Jamshoro, Mardaan, and Nawabshah for 2 years
w.e.f. December 2001 to September 2003. Leaves were
collected at the beginning, mid-point and at the end
of each month mentioned to ensure the reliability of
data. All reagents (analytical and HPLC) used were
from E. Merck, Fluka or Sigma Aldrich unless stated
2.2. Extraction of total phenolics
Extraction of Moringa leaves was carried out follow-
ing the method reported by Zuo et al. (2002). Air-dried
leaf samples (5.0 g) were ground so as to pass 1mm sieve
size and extracted with 25 mL of 80% methanol for 3 h
in an electrical shaker at room temperature. The
contents of the flasks were further extracted twice with
20 mL of 80% methanol containing 0.15% HCl under
the same set of conditions. The extracts were combined
and filtered through 0.45 mm of Nylon membrane filter.
The extracts were evaporated to dryness under reduced
pressure at 45 1C by a rotary evaporator and stored in a
freezer at 18 1C until used for further analyses.
2.3. Measurement of total phenolic content (TPC)
TPC in the methanolic extracts of M. oleifera leaves
was determined by Folin–Ciocalteu reagent assay (Folin
and Ciocalteu, 1927;Singleton and Rossi, 1965). The
reaction mixture contained 200 mL of extracts, 750 mLof
freshly prepared diluted (1:10) Folin–Ciocalteu reagent
and 2 mL of 7.5% sodium carbonate. The final mixture
was diluted to 7 mL with deionized water. Mixtures were
kept in the dark at ambient conditions for 2 h to
complete the reaction. Then the absorbance at 765 nm
was measured on a Perkin-Elmer Lambda-2 Spectro-
photometer, with a 1 cm cell. All the experiments were
conducted thrice using gallic acid as a calibration
standard, and results were recorded as gallic acid
equivalents (g/100 g of extract).
2.4. Determination of total flavonoid content (TFC)
The TFC was measured following a reported colori-
metric assay (Zhishen et al., 1999;Kim et al., 2002)with
slight modifications. Briefly, the methanolic extract of
each sample (1mL) was appropriately diluted and added
to a 10 mL volumetric flask containing 4mL of H
Initially, 0.3 mL of 5% NaNO
was added to each
volumetric flask; at 5 min, 0.3 mL of 10% AlCl
added; at 6 min, 2 mL of 1 MNaOH was added. Each
reaction flask was then immediately diluted with 2.4 mL
of H
O and mixed. Absorbance of the mixtures was
determined at 510 nm. TFC of the samples was deter-
mined as epicatechin equivalents (mg/g). Three readings
were taken for each sample and results were averaged.
2.5. Quantitative determination of ascorbic acid
Ascorbic acid determination was carried out following
a reported indophenol titration method (Anwar et al.,
1990). Samples were homogenized in metaphosphoric
acid solution and extracted. The vitamin C was titrated
against 2,6-dichlorophenol–indophenol solution at pH
0.6 in the presence of formaldehyde, to a pink end point.
S. Iqbal, M.I. Bhanger / Journal of Food Composition and Analysis 19 (2006) 544 –551 545
2.6. Determination of reducing power
Reducing power was determined following the meth-
od reported by Yen and Duh (1993). Extracts (0, 1.0,
2.0, 5.0, 7.5, 10.0, and 15.0 mg) were mixed with
phosphate buffer (5.0 mL, 2.0 M, pH 6.6) and 1%
potassium ferricyanide (5 mL), and the mixtures were
incubated at 50 1C for 20 min. The quantity 5 mL of
10% trichloroacetic acid were added and the mixture
was centrifuged at 650gfor 10 min. The upper layer of
the solution (5 mL) was mixed with distilled water
(5 mL) and 0.1% ferric chloride (1 mL), and absorbance
was measured at 700 nm. The experiment was conducted
in triplicate and results were averaged.
2.7. Antioxidant activity determination in linoleic acid
The AA of methanolic extracts was determined
following a reported method (Osawa and Namiki,
1981). Sample extracts were added to a solution mixture
of linoleic acid (0.13 mL), 99.8% ethanol (10 mL), and
0.2 Msodium phosphate buffer (pH 7.0, 10 mL). The
total volume was adjusted to 25 mL with distilled water.
The solution was incubated at 40 1C, and the degree of
oxidation was measured according to the thiocyanate
method (Mitsude et al., 1966) with 10 mL of ethanol
(75%), 0.2 mL of an aqueous solution of ammonium
thiocyanate (30%), 0.2 mL sample solution, and 0.2 mL
of ferrous chloride (FeCl
) solution (20 mMin 3.5%
HCl) being added sequentially. After 3 min of stirring,
the absorption values of mixtures measured at 500 nm
were taken as peroxide contents. A control was
performed with linoleic acid but without the extracts.
Each sample was run in triplicate and results were
2.8. Scavenging of superoxide anion radical
Superoxide anion radical scavenging activity of
methanolic extracts of M. oleifera leaves was determined
by the PMS–NADH superoxide generating system
(Nikishimi et al., 1972;Lai et al., 2001). Extracts were
added to a solution mixture that contained 200 mM
NBT, 624 mMNADH, and 80 mMPMS in 0.1 M
phosphate buffer, pH 7.4. After 2 min of incubation at
room temperature, the absorbance was measured at
560 nm. Percentage capability to scavenge the super-
oxide radical was calculated using the following
Scavenging effect ð%Þ
¼1Absorbance of sample at 560 nm
Absorbance of control at 560 nm
2.9. Statistical analysis
All the data is reported as mean7S.D. Data were
analyzed using two-way ANOVA with replications
following method reported by (Zar, 1996). Data was
considered significant at Po0:05. Statgraphics
1990–1991 Version 5.0 was used for statistical analysis.
3. Results and discussion
3.1. Total phenolic content
The phenolic compounds may contribute directly to
antioxidative action (Awika et al., 2003); therefore it is
necessary to investigate TPC. The TPC was determined
following a modified Follin–Ciocalteu method and
results were expressed as gallic acid equivalents
(Table 1).
Significant differences (Po0:05) in TPC were ob-
served as function of season and production location.
Among locations, highest TPC was observed for
samples from Mardaan followed by Balakot, Chakwal,
Jamshoro, and Nawabshah, respectively. Samples from
Nawabshah and Jamshoro, with almost identical
agroclimatic conditions and environmental temperature
(e.g., up to 51 1C during June) exhibited non-significant
differences in TPC and were the lowest among the
locations investigated. This might be attributed to the
strong effect of temperature on TPC. It is supported by
report of Wang and Zheng (2001), showing that
environmental temperature strongly alters antioxidant
properties in strawberry. Furthermore, the observation
of Yu et al. (2003) also supports the findings of the
present work, stating that solar radiation reflects the UV
exposure, which may be associated with free radical
formation and singlet oxygen production. Recently,
Anwar et al. (2005) described wide variation in oil
content of M. oleifera seeds from different agroclimatic
locations due to diversity in natural soil texture and
climatic constraints.
A survey of the literature reveals that TPC in M.
oleifera leaves from Mardaan was higher than those
reported from India, Niger, and Nicaragua (Siddhuraju
and Becker, 2003) throughout the year. The samples
collected from Chakwal and Balakot had TPC that was
higher than India but lower than Niger and Nicaragua.
Generally, the trend of TPC as a function of the
season was as: December4March4September4June
for all the locations investigated. However, for samples
from Mardaan, TPC in March was higher than in
December, perhaps due to extreme cold weather in
December in Mardaan. Results for December and
March were statistically non-significant among them-
selves, while for June and September TPC was
statistically significant (Po0:05). Temperature ranges
S. Iqbal, M.I. Bhanger / Journal of Food Composition and Analysis 19 (2006) 544 –551546
for all the locations were determined from Pakistan
Meteorological Department, and an inverse relation of
environmental temperature with TPC was observed.
Highest TPC was observed in the month of December
(coldest temperatures) while the lowest was in June
(hottest temperatures). This may be due to the fact that
Moringa leaves grow in the month of June and mature
from December to March, and phenolic content is
lowest in newly opened leaves, increasing gradually with
the maturity of leaves. Previous reports suggest that
phenolic content increases with the increase in leaf-age
and is lower in early stages of leaf growth, gradually
increasing with the maturity of leaves (Julkunen-Tiitto,
1989;Wiermann, 1981). Furthermore, the activity of the
plants is at its maximum during hot seasons (June in
Pakistan), leading to a loss of phenolic content.
However, this activity reduces with the decrease in
seasonal temperature resulting in a retention of pheno-
lics (Lavola, 1998). The report by Sanders (1982),
describing that an increase in unsaturated fatty acids is
generally associated with cooler climates leading to
production of antioxidants for a self-defense system
against environmental stress, supports our present
findings suggesting pronounced effects of environmental
temperature on AA. Some literature reports (Wang and
Stretch, 2001) reveal that an increase in TPC occurs with
the increase in storage temperature up to an optimized
level, while environmental temperature exhibited con-
troversial behavior than storage temperature in the
present study.
Another observation was made concerning the effect
of altitude on TPC. Balakot and Mardaan, at an
altitude ranging from 400–2700 ft with respect to other
locations and with strong stormy wind throughout the
year, exhibited higher TPC than those of other
locations, which are flat and have no stormy winds or
rains. Although no previous findings support this
observation directly, eastern practitioners generally
believe that plants from hilly areas are more important
from a nutritional and dietary point of view (Anwar
et al., 2004).
3.2. Total flavonoid content (TFC)
Flavonoid content was determined by a reported
method (Zhishen et al., 1999) and results were expressed
as epicatechin equivalents (Table 2). TFC was found in
appreciable amounts.
Exactly the same effects of agroclimatic location on
TFC were observed as for TPC, perhaps due to the
phenolic nature of flavonoids. However, the seasonal
effects on TFC were different from TPC, and no
significant differences among seasons for TFC could
be observed. Only the results of September versus
March and December were statistically different
(Po0:05). TFC was comparable to those of Moringa
samples from India, Niger, and Nicaragua (Siddhuraju
and Becker, 2003) and in mulberry leaves (Zhishen et al.,
1999) for all samples. However, samples from Mardaan
exhibited higher TFC than the literature values (Sid-
dhuraju and Becker, 2003). These results suggest that
Moringa leaves may be exploited as an important source
in nutraceutical and functional food industries.
3.3. Ascorbic acid concentration
Ascorbic acid (AAcid), was determined following a
reported method (Anwar et al., 1990) and results are
presented in Table 3. Slight differences among locations
could be investigated; however, the differences were
non-significant among seasons. AAcid content was
highest in the month of March for Mardaan, Chakwal,
and Balakot locations (i.e., 0.044–0.046 (g/100 g)), and
in December for those from Jamshoro and Nawabshah,
i.e., 0.037–0.039 (g/100 g). AAcid remained unchanged
during March, June, and September for Jamshoro
samples, whereas for the Nawabshah samples it was
exactly the same during December and September.
AAcid content was lowest for all the locations in June.
AAcid content in the Mardaan and Balakot samples was
comparable to Moringa samples from India and
Nicaragua (Siddhuraju and Becker, 2003) and orange-
colored carrot, while it is almost three times higher than
Table 1
Total phenolic content of methanolic extracts of Moringa oleifera leaves (g/100 g)
Nawabshah Jamshoro Mardaan Chakwal Balakot Average
Dec. 9.1770.45 9.3470.58 13.0970.38 11.8770.19 12.3970.40
Mar. 8.9870.30 9.0270.21 13.5670.11 10.7970.70 12.0870.23
Jun. 8.3770.33 8.4370.41 11.8270.31 9.6770.24 11.4770.10
Sep. 8.7470.27 9.1670.10 12.6870.36 9.8370.37 11.8370.52
All data is reported as mean7S.D.(n¼6).
F-statistics for seasons ¼26.405 at df ¼3, P¼0:000.
F-statistics for locations ¼230.496 at df ¼4, P¼0:000.
Values with same letter are statistically non-significant at 0.05 LSD.
Dec. ¼December, Mar. ¼March, Jun. ¼June, Sep. ¼September.
S. Iqbal, M.I. Bhanger / Journal of Food Composition and Analysis 19 (2006) 544 –551 547
those in yellow- and white-colored carrots (Alasalvar
et al., 2001), revealing a high nutritional value for
Moringa leaves. The overall order of AA was the same
for a specific geographic location and season, suggesting
marked influence of location and season on the AA of
Moringa leaves.
3.4. Reducing power
Literature reports (Siddhuraju et al., 2002;Yildirim et
al., 2001) show that the reducing power of bioactive
compounds is directly related to AA. A regular pattern
of increase in reducing power as a function of extract
concentration was observed (Table 4). The highest
reducing power was observed for samples from Mar-
daan followed by Balakot, Chakwal, Nawabshah, and
Jamshoro, respectively. Marked variation in the redu-
cing power was observed for all the locations and
seasons. Reducing power was lowest in June for all the
locations except from Balakot, where the lowest
reducing power was observed in September, while the
highest in December was for samples from Chakwal,
Jamshoro, and Nawabshah, contrary to those from
Balakot and Mardaan which showed the highest
reducing power in March. Results for reducing power
are comparable to those of the reducing power in Hsian-
tsao leaf gum and in case of samples from Mardaan,
reducing power is double to Hsian-tsao leaf gum (Lai
et al., 2001), which has been reported as a potent source
of antioxidant. In the light of these findings, M. oleifera
leaves may be exploited as an important source of
3.5. Antioxidant activity in linoleic acid system
AA of all the samples was observed in linoleic acid
system (Fig. 1). Significant variation in AA with respect
to season and geographic location was observed. The
same order of AA was followed, i.e., Mardaan4Bala-
kot4Chakwal4Jamshoro4Nawabshah. Highest AA
for Jamshoro, Chakwal, and Nawabshah was observed
in the month of December whereas for Mardaan and
Balakot, this occurred in March. Many species of
compounds contribute to AA, therefore biological
uptake of various antioxidant compounds like Se by
Moringa may have vital influence on the AA of samples
from different locations, which in turn depends on soil
texture and other climatic conditions (Lorenz, 1978).
Table 3
Ascorbic acid content (g/100 g) of methanolic extracts of Moringa oleifera leaves (g/100 g)
Nawabshah Jamshoro Mardaan Chakwal Balakot Average
Dec. 0.03770.01 0.03970.01 0.04270.01 0.03970.01 0.04470.01
Mar. 0.03670.01 0.03570.01 0.04570.02 0.04470.01 0.04670.01
Jun. 0.03270.01 0.03570.01 0.03670.01 0.03670.01 0.04170.01
Sep. 0.03770.01 0.03570.01 0.0470.02 0.03570.01 0.04270.00
All data is reported as mean7S.D.(n¼6).
F-statistics for seasons ¼1.174 at df ¼3, P¼0:3292,
F-statistics for locations ¼1.804 at df ¼4, P¼0:1428.
Values with same letter are statistically non-significant at 0.05 LSD.
Dec. ¼December, Mar. ¼March, Jun. ¼June, Sep. ¼September.
Table 2
Total flavonoid content of methanolic extracts of Moringa oleifera leaves (g/100 g)
Nawabshah Jamshoro Mardaan Chakwal Balakot Average
Dec. 7.3770.26 7.1270.51 12.7970.30 9.9170.25 11.9570.28
Mar. 7.0270.24 8.1470.21 12.6970.21 9.3970.27 12.1570.21
Jun. 6.5970.21 6.9370.21 12.1570.43 8.8570.14 11.6770.36
Sep. 6.7470.27 7.3470.17 12.4970.17 9.1370.18 11.8270.40
All data is reported as mean7S.D.(n¼6).
F-Statistics for seasons ¼2.526 at df ¼3, P¼0:0680,
F-Statistics for locations ¼46.167 at df ¼4, P¼0:000.
Values with same letter are statistically non-significant at 0.05 LSD.
Dec. ¼December, Mar. ¼March, Jun. ¼June, Sep. ¼September
S. Iqbal, M.I. Bhanger / Journal of Food Composition and Analysis 19 (2006) 544 –551548
3.6. Superoxide anion radical scavenging activity
Superoxide radical scavenging activity for all the
samples was measured at a concentration of 1 mg/mL;
results are shown in Fig. 2. All the extracts exhibited an
appreciable scavenging activity. Significant differences
in scavenging activity were observed among samples
from different locations and seasons. Scavenging acti-
vity was significantly affected by agroclimatic locations
in the same pattern. For samples from Mardaan, the
Table 4
Reducing power of methanolic extracts of Moringa oleifera leaves from different agroclimatic locations in different seasons
Samp month Conc. (mg) Nawabshah Jamshoro Mardaan Chakwal Balakot
Dec. 0 0.01670.001 0.02270.001 0.01370.001 0.01770.002 0.00970.001
1 0.2770.01 0.3370.01 0.4370.01 0.3970.01 0.4370.02
2 0.5070.02 0.5970.01 0.7870.01 0.7270.01 0.7670.01
5 1.3170.02 1.3270.03 1.7770.02 1.4970.03 1.6770.04
7.5 1.7870.03 1.8170.05 2.4770.07 2.0970.01 2.2270.02
10 2.2170.02 2.4270.02 3.0270.02 2.4770.02 2.6270.01
15 2.7470.03 2.7870.01 3.8470.09 3.1770.03 3.3270.03
Mar. 0 0.00970.001 0.02370.001 0.01370.001 0.02870.001 0.01970.001
1 0.2370.01 0.2770.01 0.4670.01 0.3470.01 0.4570.02
2 0.4270.01 0.4870.01 0.8370.02 0.6670.03 0.8270.04
5 1.1370.04 1.1970.01 1.8670.04 1.4070.06 1.7670.05
7.5 1.6670.03 1.6170.02 2.5470.05 1.9270.03 2.3170.02
10 1.9770.02 2.0570.04 3.1970.12 2.4170.01 2.7970.03
15 2.5970.02 2.4970.03 4.0270.02 3.0770.03 3.3970.07
Jun. 0 0.00770.001 0.01470.001 0.01870.001 0.0270.001 0.01570.001
1 0.1970.01 0.2270.01 0.3970.01 0.2970.01 0.3970.01
2 0.3770.01 0.4070.01 0.6770.01 0.5370.02 0.6870.03
5 1.0470.04 0.9170.02 1.5870.03 1.2470.01 1.4770.06
7.5 1.5270.02 1.3270.03 2.2770.08 1.7370.04 2.0770.03
10 1.8070.02 1.6670.01 2.8470.04 2.0470.01 2.5470.02
15 2.4170.06 2.3170.02 3.6970.06 2.4270.03 3.2770.06
Sep. 0 0.01970.001 0.00870.001 0.02170.001 0.02470.002 0.00370.001
1 0.1970.01 0.2670.01 0.4270.01 0.3170.01 0.3970.01
2 0.4170.02 0.4670.01 0.7270.02 0.5770.01 0.7170.02
5 1.0470.03 1.0470.01 1.8170.03 1.3070.02 1.5670.02
7.5 1.5770.01 1.4570.02 2.4570.01 1.8170.03 2.0070.04
10 1.8570.03 1.8970.02 2.9670.07 2.1970.02 2.4270.01
15 2.4970.01 2.4670.03 3.7870.04 2.7670.02 3.2170.06
All data is reported as mean7S.D.(n¼6).
Statistical analysis was subjected to values of 5 mg for all locations and seasons.
F-Statistics for seasons ¼56.523 at df ¼3, P¼0:0000.
F-Statistics for locations ¼264.785 at df ¼4, P¼0:0000.
Values with same letter are statistically non-significant at 0.05 LSD.
Dec. ¼December, Mar. ¼March, Jun. ¼June, Sep. ¼September.
Nawabshah Jamshoro Mardan Chakwal Balakot
Production Locations
Inhibition of peroxidation (%)
.Dec. Mar.
Jun. Sep.
Fig. 1. Antioxidant activity of methanolic extracts of Moringa oleifera in linoleic acid system.
S. Iqbal, M.I. Bhanger / Journal of Food Composition and Analysis 19 (2006) 544 –551 549
highest scavenging activity was observed in March and
the lowest in June. For all other locations the highest
scavenging activity was in December and lowest in
March for Nawabshah, in June for Chakwal, Mardaan,
Jamshoro, and Balakot. For Nawabshah, a controversy
relative to previous results was observed, reducing
power in June was far higher than in September
and March. Overall order of scavenging was similar to
TPC, TFC, and reducing power for all the locations.
Results of scavenging effects for Jamshoro, Nawabshah,
and Chakwal were closer to one another, while
Balakot and Mardaan exhibited closer values among
4. Conclusions
From the present work, it could be concluded that
agroclimatic locations and seasons have profound
effects on the AA of M. oleifera leaves. AA of samples
from cold areas was relatively higher than those from
temperate regions. Similarly, from all the samples, AA
was highest in December (cold month) and lowest in
June (hot month), with few exceptions. These findings
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... The leaves, fruits, flowers and immature pods are edible and form part of traditional diets in many countries of the tropics and sub-tropics (Siddhuraju and Becker, 2003) [21] . It is documented in eastern allopathic medicine to possess various pharmacological actions, such as analgesic, antihypertensive activity, antiinflammatory effects (Shahid and Bhanger, 2006) [20] . Different parts of this plant contain a profile of important minerals and are a good source of protein, vitamins, beta-carotene, amino acids and various phenolics (Anwar et al., 2007) [2] . ...
... The leaves, fruits, flowers and immature pods are edible and form part of traditional diets in many countries of the tropics and sub-tropics (Siddhuraju and Becker, 2003) [21] . It is documented in eastern allopathic medicine to possess various pharmacological actions, such as analgesic, antihypertensive activity, antiinflammatory effects (Shahid and Bhanger, 2006) [20] . Different parts of this plant contain a profile of important minerals and are a good source of protein, vitamins, beta-carotene, amino acids and various phenolics (Anwar et al., 2007) [2] . ...
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In the present investigation has been made to estimate the effects of different chemical treatments on wholesomeness and post harvest storage qualities of drumstick pods (Moringa oleifera). Drumsticks have good nutritional and therapeutic values used to prevent or treat protein-energy malnutrition. The storage of moringa makes the pods available throughout the year and enables the farmer to get fair price even during the peak production seasons. The fresh and cleaned drumstick pods were treated with calcium chloride (1%) and bavistin (0.1%) and packed in LDPE and HDPE packaging material and finally stored at ambient and refrigerated condition. the data obtained from outcome of research revealed that the sample packed in HDPE and stored at refrigerated condition founded better results as compare to other samples. The drumsticks pods treated with calcium chloride solution found superior results as compare to bavistin solution. From the research it was concluded that calcium (1%) treated drumstick pods stored under refrigeration condition which packed in HDPE packaging material was better in overall qualities.
... 12 These minor differences in antioxidant activity can be attributed to the fact that they were harvested from various regions and had different phytochemical compositions. 52 These findings support previous findings that FS methanolic extract has moderate antioxidant activity. ...
... 12 These variations in antibacterial activity can be attributed to the fact that the materials were collected from various locations and had different phytochemical contents. 52 These results provide confirmatory evidence that FS methanolic extract is sensitive to P. aeruginosa, B. cereus, S. aureus, and E. coli bacteria strains. There is enough evidence from previous studies to support the relationship between certain bacteria and cancer. ...
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Background Ferulago setifolia K. Koch (Apiaceae) has been the subject of this study, aiming to comprehensively determine its phenolic fingerprint and evaluate its various biological activities. The LC‐MS/MS analysis of the 70% methanol extract of Ferulago setifolia (FS) has revealed the presence of 23 phytochemicals. Among them, chlorogenic acid, quinic acid, kaempferol‐3‐ O ‐glucoside, and quercetin‐3‐ O ‐glucoside were identified as the major phenolics in the extract. Results The biological screening included examinations of antioxidant, antibacterial, antiproliferative, and cytotoxic activities. The FS extract displayed moderate DPPH radical scavenging and ferric‐reducing capacity, indicating moderate antioxidant activity. Furthermore, FS exhibited significant antiproliferative effects on cancer cells while showing low cytotoxicity on normal cells. The antibacterial activity findings revealed that FS demonstrated potent activity against Pseudomonas aeruginosa , Bacillus cereus , Staphylococcus aureus , and Escherichia coli . Conclusion The findings of this study suggest that the methanolic extract of FS holds promise as a potential source of biologically active compounds. It can be utilized for the development of pharmaceutical formulations, thanks to its significant antiproliferative and antibacterial activities. Additionally, FS can serve as a valuable source of chlorogenic acid for industrial applications. This article is protected by copyright. All rights reserved.
... This plant is well-known for its nutritional richness, the plant's leaves, seeds, flowers, and roots are utilized for various purposes (Padayachee and Baijnath 2012). It has been consumed as a food, fodder, medicines and several industrial applications (Fahey, 2005;Iqbal and Bhanger 2006). Moreover, owing to its economic significance, it also called "Miracle tree." ...
... The loss in the control sample was 131.45 and in the coated sample were 83.3, 72.9, 54.8, and 51.5 mg GAE per 100g respectively. The change may be due to many factors such as variety, species, ripening, and environmental conditions [44]. According to Taylor (1993), the lowering in total phenol content can reduce the astringency during the storage period [45]. ...
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Guavas (Psidium guajava) are regarded as one of the most perishable commodities, primarily owing to their climacteric characteristics and heightened metabolic processes, resulting in a faster rate of softening. Edible coating is a natural ingredient that is employed as an alternative to extend the shelf life of fruits while also providing bioactive and functional compounds. Aloe vera gel is predominantly used for this purpose due to its widespread availability. Various concentrations of aloe vera-based coating formulation (25%, 50%, 75%, and 100%) were applied on fresh whole guava by dipping method. The guava was stored at a refrigerated condition (4°C) and weight loss, color, firmness, vitamin C, total phenol, and pH change were observed in this research. A significant effect of aloe vera coating was found over the storage period. Aloe vera treatment lowered the weight loss, and retarded the texture and color compared to the control sample throughout the 28 days of storage. Vitamin C and total phenol content remined high at 141.4 mg/100g and 219.6 mg GAE/100g respectively in a 100% aloe vera coated sample after 28 days of storage compared to the control. Among 25%, 50%, 75%, and 100% aloe vera coated sample, 100% aloe vera was found to be the best coating material to prevent physical changes in fresh guava.
... These elements' quantity differences might be attributed to different environmental, soil, and altitudinal conditions. The soil composition determines the composition and quantity of elements present in these plants [46]. The presence of such essential and vital elements in wild edible plants has also been detected and reported by other researchers in their studies [47][48][49][50][51]. ...
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Human beings have used wild edible plants (WEPs) for food since ancient times. The poor and underprivileged people of the district of Malakand, Pakistan, also depend on wild edible plants (WEPs) to fulfill their food and nutrition needs. Wild edible plants (WEPs) are a potential solution for overcoming food shortages for families living in rural areas. The current study evaluated the ethnobotanical, nutritional, and elemental potential of some wild edible plants (WEPs) commonly used by local people in the district of Malakand, Pakistan. Ethnobotanical information was collected from local people through a semi-structured questionnaire. The ethnobotanical information collected about wild edible plants revealed that two wild edible species belong to the family Fabaceae, two plant species belong to the family Polygonaceae, and one plant species belongs to each family Amaranthaceae, Brassicaceae, Chenopodiaceae, Malvaceae, Oxalidaceae, and Portulaceae. The plants collected were all herbs, and the parts used as edible parts were mostly leaves and young shoots. All the collected plants were predominantly used as vegetables by local people. The proximate nutritional analysis was carried out according to the official methods of AOAC (from 2016). The proximate nutritional analysis revealed that the selected WEPs are a good source of important nutrients like carbohydrates, proteins, fibers, fats, and caloric energy. The proximate nutritional analysis of selected WEPs revealed that the highest (%) moisture content was calculated in Nasturtium officinale W.T. Aiton (90.45 ± 0.3); the highest dry matter (%) was present in Oxalis corniculata L. (21.60 ± 0.2); the highest ash (%) in Chenopodium album L. (17.80 ± 0.3); the highest crude fibers (%) in Meliolotus indicus (L.) All (16.45 ± 0.5); the highest crude protein (%) in Meliolotus indicus (L.) All (14.40 ± 0.1%); the highest crude fats (%) in Rumex hastatus Don. (3.80 ± 0.04); the highest percentage of carbohydrates in Portulaca oleracea L. (65.38 ± 0.6); and the maximum energy value was calculated for Portulaca oleracea L. (321.38 ± 0.4 Kcal/100 g). The elemental analysis of wild edible plants (WEPs) was carried out through energy-dispersive X-ray analysis (EDX). The EDX analysis showed that these WEPs consist of crucial and imperative elements such as C, O, N, P, Mg, K, S, Ca, Al, Si, Cl, Fe, Cu, Na, and Zn, which are integral parts of the human diet. Following the results of the EDX elemental analysis, Portulaca oleracea accounted for the highest concentration (%) of carbon, Oxalis corniculata accounted for the highest concentration (%) of oxygen, and Nasturtium officinale accounted for the maximum concentration of nitrogen (9.70%). The current study revealed that the research area is rich in diversity of wild edible plants (WEPs), a cheap and economical food source for locals. The study also showed that these wild edible plants (WEPs) possess all the crucial nutrients and elements imperative for human food and health. These wild edible plants (WEPs) will play a key role in a sustainable food system in the future.
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Medicinal plants are indispensable sources of bioactive compounds and have proved to be stalwart ingredients for a wide range of applications. The potency of five different solvents in extracting bioactive constituents; qualitative and quantitative determination of phytochemicals of red soko and green soko were studied. The plant were cut into smaller pieces, air-dried, ground into powdery sample, sieved with 40 mm mesh size and properly labelled. Each sample was extracted using five different solvents (acetone, chloroform, ethyl acetate, methanol and water) at ratio 1: 10 for 72 h. Each solvent extract was screened for nine phytochemicals (flavonoid, carotenoid, phenol, oxalate, tannin, saponin, alkaloid, phytate and ascorbic acid). It was observed that the plant extract contained seven phytochemicals in both red and green soko. The highest extractive values and qualitative screening of phytochemicals in red soko and green soko were obtained in water and methanol extracts. Quantitative phytochemical analysis showed that there was higher content of saponin, phytate and ascorbic acid in the two vegetables. Red soko contained lower ascorbic acid, saponin, total phenol, total carotenoid, alkaloid and flavonoid than green soko while green soko had lower phytate and tannin than red soko. There was no significant difference (P˂0.05) in flavonoids, total carotenoid and alkaloid contents in red soko and in green soko there was no significant difference (P˂0.05) in total carotenoid and alkaloid contents.
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To describe the kidney's response to specific substances, such as dangerous compounds and pharmaceuticals, the term "nephrotoxicity" is employed. When the body is subjected to toxins or medications, nephrotoxicity is among the most prevalent side effects. Numerous medical treatments, including anti-cancer medicines, antibiotics, and some Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), can cause nephrotoxicity. This review discusses a variety of drugs that can preserve the kidneys. The nephroprotective qualities of natural substances, medicinal plants, and dietary components have been examined. Medicinal plant chemicals have a significant role in pharmaceutical research. A wide range of herbs has been shown to have nephroprotective effects. Treatment of renal calculi, prevention of diabetic nephropathy, and reduction in tubular damage were all achieved. Plant-based therapies contain phytochemicals that have nephroprotective properties. Plants with nephroprotective activities have been reported on cisplatin, gentamicin, adriamycin, and urolithiasis, caffeic acid phenethyl ester assists in nephrotoxicity and free radicals radical scavenging activity, which may be utilized to prevent and treat kidney damage. In the end, investigating traditional medicines from Bangladesh that contain kidney-protecting plants is an intriguing new avenue of inquiry that could lead to effective new therapies for renal illnesses. Maintaining kidney health and enhancing the lives of countless people is only possible with further investigation into the beneficial effects of plants on renal function. However, it is crucial to find a middle ground between ancient practices and evidence-based modern medicine, stressing the importance of making educated decisions and following expert guidance to guarantee uncompromised kidney health.
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Post- harvest treatment of the fruit is a major issue and there are a lot of conservative methods all around the world. In India, fruits are picked green and stored in ventilated rooms at 15°C-21°C for a week. There is no precise information on the exact stage of harvest and effect of ripening treatments on the nutritional, bioactive and antioxidant composition of mangoes. New knowledge about mango consumption is relevant to rational development in knowing the right stage for mango consumption with highest nutrient and phytochemical potential. In view of this, a study was taken up to investigate “Effect of maturity stages and ripening process on the nutrient and bioactive composition of Mango (Mangifera indica L.) var. Banganapalli”. In this study, comparison of two stages of maturity (commercial maturity: 7-9˚brix and physiological maturity: 9-11˚brix) of the selected mango cultivar and three different ripening processes (control ripening, 100 ppm ethylene ripening and 150 ppm ethylene ripening) and their effect on the physico-chemical, nutrient and bioactive components of the pulp were studied.
Conference Paper
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Gas built-in hobs have spring brackets that press the burner pool against the burner plate. These brackets are made of spring material with different forms and bends according to the place of use. The main features expected from these brackets are to overcome the force arising from the weight of the burner pool and to protect the position of the burner pool before and after installation and not to be affected by the heat fluctuations that will occur in the hob. For this reason, these brackets must remain within the limits of elastic deformation. The compression force of the brackets against the glass compression force before and after assembly and the forces against the tensile force during the assembly of the burner pool are affected by the part design and spring material type. For these reasons, in this study, tensile and compression analysis of spring brackets used in gas built-in hobs were carried out in Ansys structural interface. In the light of the data obtained, a method has been put forward in which it is possible to use springs with the most suitable mechanical and physical properties with a correct spring design.
Antioxidative activity of aromatic amino acids and indole compounds for the autoxidation of linoleic acid was found to correlate in some extent with the highest occupied molecular orbital energy which represents the electron donor property of respective molecule. 5-Hydroxytryptophan, one of the best electron donor among the compounds tested, was the most effective antioxidant. However, antioxidative activity of some indole compounds could not be interpreted simply by their highest molecular orbital energies. Neither the chelating action for the possible metal traces nor the accelerated decomposition of hydroperoxide produced during the course of the reaction explained these actions of indoles. Tryptophan, while preventing the autoxidation of linoleic acid, underwent the ring cleavage at the position of between C2 and C3 or hydroxylation at C5 to yield formylkynurenine, kynurenine, 3-hydroxykynurenine, 5-hydroxytryptophan, 5-hydroxyindoleacetic acid, etc. Following mechanisms which were compatible with the experimental results were proposed for the antioxidative action of indoles; indole donates an electron from its π-pool to linoleic acid radical or peroxy radical produced during the autoxidation of linoleic acid to form a loose charge transfer complex through a “local” interaction; an electron transfer occurs within the complex, which brings cleavage of indole rings and an inhibition of autoxidation.