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O R I G I N A L C O N T R I B U T I O N Open Access
Comparison and HPLC quantification of
antioxidant profiling of ginger rhizome,
leaves and flower extracts
Saira Tanweer
1,2*
, Tariq Mehmood
1,3
, Saadia Zainab
4,5
, Zulfiqar Ahmad
2
and Aamir Shehzad
1,6
Abstract
Background: In the present era, the attention of nutritionist diverted towards the bioactive entities present in
natural sources owing to the presence of health boosting perspectives against lifestyle related disarrays.
Methods: In this context, different parts of ginger crop i.e. rhizome, leaves and flower of variety Suravi (ID no. 008)
were used for the preparation of ginger extracts with 50% methanol, 50% ethanol and water via rotatory shaker for
45 min. After that, different phytochemical analysis and in vitro analyses were carried out to determine the
antioxidant potential of these extracts. Lastly, the best selected extracts from each part was quantified through
HPLC.
Results: The results of current investigated indicated that ethanol extract proved to have maximum quantity of
phytoceutics as compared to methanol and water. The maximum TPC, flavonoids, flavonols, DPPH assay,
antioxidant activity, FRAP assay, ABTS assay and metal chelating potential was observed in ginger leaves as
780.56 ± 32.78 GAE/100 g, 253.56 ± 10.65 mg/100 g, 49.54 ± 1.74 mg/100 g, 75.54 ± 3.17%, 77.88 ± 3.27%, 105.72 ±
4.44 μmole TE/g, 118.43 ± 4.97 μmole TE/g and 35.16 ± 1.48%, respectively followed by ginger flowers and ginger
rhizome. The lowest antioxidant activity was estimated in ginger rhizome. On the basis of phytochemical profiling
and in vitro analyses, ethanol extracts of ginger flowers, leaves and rhizome were selected for the quantification
through HPLC.
Conclusion: The findings proved that maximum 6-gingerol was present in ginger leaves (4.9 mg/g) tackled by
ginger flowers (2.87 mg/g) and ginger rhizome (1.03 mg/g).
Keywords: Phytochemical screening, In vitro analysis, Quantification, HPLC, Gingerol
Background
Owing to the raising amount of remedies and their side
effects on the health stratum of individuals forced the
community to replace them with some phytodrugs. The
food material that is mostly utilized as the source of
nutraceutics are fruits, vegetables along with a number
of spices that are used on daily basis in normal lifestyle.
These food commodities enclosed extraordinary number
of bioactive moieties that can be illustrated by volatile
and non-volatile assay. The phytochemicals extracted
from these foods have numerous medicinal properties
[1]. In this context, herbs and spices are mostly used for
the purpose of seasoning and to provide taste as well as
flavor to the food products. These herbs and spices have
already extensively used in almost all folk medicines and
traditional food products that were used to improve the
health of community. From previous decades, ginger rhi-
zome is being broadly used to treat many lifestyle related
disorders [2].
Along with ginger rhizome, ginger leaves and
flowers can also be used to demonstrate health bene-
fits of phytochemicals present in them that can com-
pelled their extraction over and above to
characterization in many food products to lead them
at the rank of designer foods. A number of extraction
© The Author(s). 2020 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made.
* Correspondence: sairatanweer1116@gmail.com
1
National Institute of Food Science and Technology, University of Agriculture
Faisalabad, Faisalabad, Pakistan
2
Department of Food Science and Technology, The Islamia University of
Bahawalpur, Bahawalpur, Pakistan
Full list of author information is available at the end of the article
Tanweer et al. Clinical Phytoscience (2020) 6:12
https://doi.org/10.1186/s40816-020-00158-z
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
techniques have been used to extract and quantify the
bioactive entities of ginger rhizome, flowers and
leaves classified as phenolic compounds. These bio-
active or phenolic compounds have retained a strong
position in inherit and chemical activities of ginger
family [3]. In the phytochemistry of plants, phenolic
moieties have been recommended as the most im-
portant bioactive compound that are liable to be used
as health boosting ingredients and can be recom-
mended as antioxidants. These phytochemicals are
highly reactive in nature and can oxidize the free rad-
ical molecule such as superoxides owing to the scav-
enging property and can limit the process of lipid
peroxidation [4].
For the prophylactic potential of ginger rhizome,
flowers and leaves, it is necessary to get the bioactive
entities in extracted form from the original source.
For the extraction of phytoceutics from ginger parts,
the extraction depends upon the particle size of bio-
active moiety along with its chemical nature. The rhi-
zome, flower and leaves of ginger based extracts have
diverse classes of total phenolic entities that are easily
soluble in all the polar solvents. For the purity of bio-
active compounds, it is recommended that the ginger
especially flower and leaves should be free from fat,
waxes and chlorophyll [5].
The yield as well as the efficiency of bioactive en-
tities are depended on the polarity of solvent along
with the concentration of flavonoids present in the
sample from which it is isolated. The solvent also
have strong impact on the quantity as well as quality
of total phenolic compounds (TPC) and total flavo-
noids. According to review, ethanol elucidated highest
amount of TPC as compared to methanol, acetone,
ethyl acetate and water. However, still more experi-
mental trails are required to determine the effect of
solvent on the phytochemical profiling of different
parts of ginger crop [6].
After the process of extraction, the chromatographic
method are used as technique to save the environment
with more accuracy rate, precise and reproducible con-
clusions such as fast pressure column, gas chromatog-
raphy and liquid chromatography. Each of these
technique, is reliable on the nature of elucidated com-
pound by keeping in view the sensitivity of the instru-
ment. For this purpose, high performance liquid
chromatography (HPLC) is a conclusive instrument for
the quantification and characterization of bioactive com-
ponents present in the extracts of different parts of gin-
ger. Different parameters are used in HPLC depending
upon the assorted difference in the structure of bioactive
entities extracted in extracts such as column
temperature, type of detector used, pressure difference
as well as wavelength [7].
The quantification of bioactive entities of ginger ex-
tracts through HPLC depicted that the most abundant
bioactive ingredient was gingerol as 3.436 mg/g however,
the amount of gingerol decreased and converted to sho-
gaol by increasing the temperature during the drying
process of ginger. Among gingerol series, 6-gingerol was
from 1.030–3.046 mg/g in fresh ginger followed by 8-
gingerol 0.105–0.312 mg/g and 10-gingerol 0.078–0.425
mg/g [8].
Materials and methods
Procurement of materials
Ginger rhizome, leaves and flowers as raw material with
special reference to variety Suravi (ID no. 008) was pro-
cured from South China and stored in Functional and
Nutraceutical Research Section of NIFSAT, UAF. All the
reagents HPLC graded as well as analytical graded along
with their standards were ordered from Sigma Aldrich
(Sigma Aldrich Tokyo, Japan) and Merck (Merck KGaA,
Darmstadt, Germany).
Sample preparation
All the parts of ginger crop (rhizome, leaves and flowers)
were cut into small parts up to the required size and
then sun dried in maximum sun light timing and then
processed to remove all the fatty material and chloro-
phyll. The resultant 50% dried ginger cuts were analyzed
for further chemical properties.
Preparation of ginger extracts
The extracts were prepared by using minimally proc-
essed ginger rhizome, leaves and flowers by using 50% v/
v methanol, 50% v/v ethanol and water for 45 min as dis-
cussed in the protocol of Arutselvi et al. [9] and men-
tioned in Table 1. Following that, the methanol and
ethanol-based extracts were subjected to the rotary evap-
orator (Eyela, Japan) to eliminate water molecules from
extracts and then extracts were stored for further
analyses.
Table 1 Treatments for solvent extraction
Treatment Solvent Part
T
1
Methanol Rhizome
T
2
Ethanol Rhizome
T
3
Water Rhizome
T
4
Methanol Leaves
T
5
Ethanol Leaves
T
6
Water Leaves
T
7
Methanol Flower
T
8
Ethanol Flower
T
9
Water Flower
Methanol = (50% methanol + 50% water)
Ethanol = (50% ethanol + 50% water)
Tanweer et al. Clinical Phytoscience (2020) 6:12 Page 2 of 12
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Phytochemical screening test
Total phenolic contents (TPC)
For the determination of total phenolic contents (TPC)
of ginger rhizome, leaves and flowers were measured
separately by using Folin-Ciocalteu method as prescribed
by Chan et al. [10]. This method is based on the forma-
tion of phosphotungstic blue as reduced form of phos-
photungtic acid and resulted in increased absorbance
owing to the increased number of aromatic phenolic
groups. For this purpose, 50 μL of ginger extracts along
with 250 μL of Folin-Ciocalteu’reagent and 750 μLof
sodium carbonate (20% solution) were added in a
washed and dried test tube then the total volume of test
tube was raised to 5 mL by the addition of distal water.
After that, the sample was stored for 2 h and the absorb-
ance were measured at 765 nm by using spectrophotom-
eter (CECIL CE7200) in contrast with control and blank
samples. The results of absorbance were then compared
with the standard of gallic acid equivalent (mg gallic acid
per 100 g of extract).
Flavonoids
Total flavonoid content of ginger rhizome, leaves and
flowers (individually) were determined by using spectro-
photometer method in which the flavonoid-aluminum
complex was formed as mentioned by Bushra et al. [11].
For the determination of total flavonoid, quercetin was
used as standard. For this purpose, 1 mL of ginger ex-
tract was added with 5 mL of distal water and 0.3 mL of
sodium nitrite (5% v/v solution) in a volumetric flask of
10 mL. After the rest of 5 min, 2 mL of NaOH (1 M solu-
tion) and 0.6 mL of AlCl
3
(10% w/v solution) was added.
After that. The absorbance was measured at 510 nm by
using spectrophotometer. The data was expressed as
quercetin equivalent in mg/100 g of extract).
Flavonols
The flavonols were estimated by following the guidelines
of Kumaran and Karunakaran, [12]. The standard used
was quercetin because it is almost present in all herbs
and spices and can be easily extracted in pure form. Ac-
cording to this method, 1 mL of ginger extract of ginger
rhizome, flower and leaves was mixed with 3 mL of so-
dium acetate (5% solution) and 1 mL of aluminum tri-
chloride (2% solution). After the resting time of 150 min,
the absorption was measured at 440 nm by utilizing
spectrophotometer. The standard used for flavonols was
quercetin curve that was estimated by using 1 mg of
quercetin in 0.150 to 0.05 mg in 1 mL methanol solution.
The same chemicals were used for control and blank
samples except any ginger extract. The value for total
flavonols was expressed as mg quercetin per 100 g of
extract.
In vitro studies
Free radical scavenging activity (DPPH assay)
DPPH as 1, 1-diphenyl-1-picrylhydrazyl is a non-
reactive, highly colored and stable oxidizing radical that
ended by the formation of DPPH-H (a yellow colored
hydrazine) linked up with the abstraction of hydrogen
atom in free form from the phenolic compound or/and
antioxidant. To depict the DPPH assay of ginger extracts
(rhizome, leaves and flowers), the method of Gupta and
Prakash, [13], sample solution was prepared by mixing
0.025 mL of ginger extract (separately) in 10 mL of re-
spective solvent in which extract was prepared. Follow-
ing this, 3 mL of freshly prepared DPPH solution (1% in
methanol) was dissolved in extract solution. The rest
timing of this reaction was 15 min at ambient location
and then the value was measured by spectrophotometer
at 517 nm. Likewise, the absorbance of control and blank
samples were also determined by UV/Visible spectro-
photometer at same wavelength. The results of DPPH
assay were expressed in percentage.
Antioxidant activity (AA)
The antioxidant activity of ginger rhizome, leaves and
flowers extracts (individually) was depended on the com-
bined oxidation of linolenic acid with ß-carotene. The
antioxidant activity of ginger leaves was elucidated by
following the protocol of Abd El-Baky and El-Baroty,
[14]. According to their protocol, 2 mg of ß-carotene
was dissolved in a test tube by adding 20 mL of chloro-
form then aliquot (3 mL) of this mixture was added sep-
arately with 40 mg of linolenic acid in a flask along with
400 mg of tween 20 as emulsifier. After adding all the re-
agents, the mixture was then subjected to the evapor-
ation by using rotary evaporator for 10 min at 40 °C to
remove chloroform from the mixture. After evaporation,
the mixture was mixed with 100 mL of distal water by
placing the sample at vortex mixer that helps to prepare
emulsion. In the last 2 mL of this emulsion was mixed
with thoroughly with 0.12 mL extract of ginger and incu-
bated in water bath at 50 °C for half hour. Then the ab-
sorbance of mixture was measured by
spectrophotometer using 470 nm wavelength. The anti-
oxidant activity of ginger extracted were depicted as in-
hibition percentage against control value by following
the equation:
AA %ðÞ¼
Degradation rate of control Degradation rate of sample
Degradation rate of control
100
Ferric reducing antioxidant power (FRAP) assay
The reducing potential of ginger rhizome, leaves and
flowers were determined by calculating the ability of
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extracts to reduce ferric tripyridyltriazine into blue col-
ored ferrous ions that can be measured at 593 nm wave-
length by using UV/Visible Spectrophotometer as
mentioned by Chan et al. [10]. For this purpose, FRAP
reagent was prepared by dissolving 2.5 mL 20 mM of fer-
ric chloride and 2.5 mL of 10 mM TPTZ with 25 mL 0.1
M of acetate buffer (pH 3.6). After that, the mixture was
incubated for 10 min at 30 °C. To estimate the reducing
potential of ginger extracts, 100 μL of ginger extract was
mixed with 1.5 mL of FRAP reagent along with 100 μL
of distal water then the absorbance was measured by
using spectrophotometer at 593 nm. The curve for cali-
bration was drawn by using 0–500 μmol/mL of trolox
and expressed as μmol trolox equivalent/g of sample.
ABTS (2, 2-azino-bis, 3-ethylbenzothiazoline-6-sulphonic
acid) assay
ABTS assay is a method in which decolorization was es-
timated as mentioned by Kang et al. [15]. According to
their protocol, ABTS reagent solution was freshly pre-
pared by adding 5 mL of 14 mM ABTS solution with 5
mL of 4.9 mM potassium persulfate and then the mix-
ture was stored for 16 h in dark place at ambient
temperature. Then the solution was further diluted with
respective solvent to produce absorbance of 0.7 ± 0.02 at
wavelength of 734 nm. After preparation of standard ab-
sorbance solution, 1 mL of final solution was prepared
by having 50 μL of ginger extract (either rhizome, leaves
or flower) and 950 μL of ABTS solution. After 5 min of
resting time at room temperature, the absorbance was
recorded at 734 nm by sing spectrophotometer and the
outcome were compared with the blank and control
ABTS solution. The ABTS assay was expressed as
TEAC/g sample.
TEAC: μmol trolox equivalent antioxidant capacity
Metal chelating potential
For the estimation of metal chelating potential of ginger
rhizome, leaves and flower, ferrous ion chelation was
performed as guided by Xie et al. [16]. In this procedure,
0.1 mL of ginger extract (separately) mixed with 0.05 mL
of 2 mM FeCl
2.
The mixture was mixed thoroughly for
10 min at ambient temperature then the absorbance of
solution was observed by spectrophotometer at 562 nm.
The following equation as used to express metal chelat-
ing potential of ginger extracts:
MC %ðÞ¼
Ablank Asample
Ablank
100
A: Absorbance
Selection of best treatment for HPLC analysis
From the nine treatments aforementioned in Table 1,three
best treatments each from rhizome, leaves and flower were
nominated for HPLC analysis depending upon the antioxi-
dant profiling tests and in vitro perspectives.
Characterization of active ingredients
The best selected treatment from ginger rhizome, leaves
and flower were characterized for the concentration of
bioactive compound i.e. gingerol by following the
method mentioned by Salmon et al. [17] through HPLC
(PerkinElmer, Series 200, USA) having shim packed C
18
column (CLC-ODS) having diameter properties of 15
cm × 4.6 mm and 5.0 μm range for partial size along with
auto sampler. For the separation of bioactive compound
isocratic HPLC grades acetonitrile and water (55:45 v/v)
was used as mobile phase with 100 mL/min flow rate.
Then 10 μL of sample was injected in the column at
40 °C temperature that was maintained for the complete
process. At the end, the eluted material was assessed by
using UV detector at 280 nm to calculate the amount of
gingerol present in eluent. The amount was quantified
by comparing the retention time of peaks in sample in
contrast to gingerol standard peaks.
Statistical analysis
The obtained data for each parameter was subjected to
statistical analysis to get accurate, precise and compre-
hensive conclusions. For the purpose, 2-way factorial de-
sign was applied by using Statistical Package (Statistix
8.1) to determine the level of significance as mentioned
by Montgomery, [18]. Significant ranges were further
compared by post-hoc Tukey’s HSD test.
Results and discussion
Phytochemical screening test
Total phenolic contents
Phenolics over and above to the antioxidant perspectives
owing to the valuable health boosting ability have been
recognized as an essential ingredient in daily diet. It is
depicted from mean values that total phenolic com-
pounds have significantly affected by solvent and plant
part however, the effect was observed as non-significant
for part and solvent interaction. According to Table 2,
the overall values of total phenolic compound (TPC) for
methanol, ethanol and water extracts were 533.86 ±
21.60, 687.16 ± 28.86 and 348.30 ± 12.19 mg gallic acid
equivalent (GAE)/100 g, accordingly, however, the values
regarding rhizome, leaves and flower part were 459.68 ±
18.39, 615.78 ± 24.63 and 513.86 ± 20.55 mg GAE/100 g
for rhizome, leaves and flower, accordingly. Maximum
phenolic contents were observed as 780.56 ± 32.78 GAE/
100 g in leaves ethanolic extract.
Tanweer et al. Clinical Phytoscience (2020) 6:12 Page 4 of 12
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The findings of current investigation were in line
with the outcomes of Kaur and Kapoor, [19]who
assessed the TPC level of ginger rhizome in water ex-
tract and reported that the value for the extract was
221.3 ± 9.4 mg GAE/100 g. The ginger parts showed
maximum TPC in ethanol extract followed by metha-
nol and water extracts as reported by Cai et al. [20]
and Hinneburg et al. [21]. Another group of scien-
tists, Stoilova et al. [22] worked on the different parts
of ginger and concluded that different parts have dif-
ferent amounts of total phenolic contents. The max-
imum contents were found in green part of ginger
that was 871 mg GAE/g of sample [23–28].
Meanwhile, Shirin and Prakash, [29] worked to deter-
mine the effect of different solvents namely, ethanol,
methanol and acetone on ginger and reported that high-
est TPC were calculated in ethanol extract (800 ± 4.3 mg
GAE/100 g) followed by methanol extract (780 ± 5.0 mg
GAE/100 g) and acetone extract (325 ± 1.9 mg GAE/100
g). Numerous other researches also support the concept
of present research work that ethanol has greater poten-
tial to extract phenolic compounds as compared to
methanol and water. Furthermore, it was also suggested
by literature that green parts of ginger have strong anti-
oxidant power as compared to the rhizome [30–34].
Flavonoids
It has been proved from literature that flavonoids have
strong antioxidant potential and have momentous im-
pact on the human health as well as nutritional status.
Flavonoids work on the principle to scavenge the free
radicals. Purposely, flavonoids of different ginger parts
i.e. flowers, leaves and rhizome were estimated by using
methanol, ethanol and water as solvent. The statistical
analysis revealed that both part and solvent have
significantly affected the flavonoid content however, the
interaction showed non-momentous effect on total fla-
vonoids. The flavonoids values (Table 2) suggested that
the highest flavonoid contents were observed in ethanol
extract (245.40 ± 10.31 mg/100 g) followed by methanol
extract (235.80 ± 9.20 mg/100 g) and water extract
(228.68 ± 8.00 mg/100 g). The interaction effect for fla-
vonoid content concluded that ethanol was the best
solvent among all and leaves were the best parts among
all the ginger parts and ranked with highest flavonoid
contents as 253.56 ± 10.65 mg/100 g. From part point,
leaves showed maximum flavonoids content (246.52 ±
9.86 mg/100 g) and lowest were in rhizome (230.64 ±
9.23 mg/100 g).
The results of current research work were in harmony
with the findings of numerous scientists who agreed that
the flavonoids exist in different concentrations in all the
parts of ginger crop. The highest flavonoid contents were
observed in leaves as compared to flowers and rhizome [10,
29,35]. Moreover, Ghasemzadeh et al. [28] concluded that
the polarity of solvent has greater influence on the flavon-
oid content of sample. By increasing the polarity, the rate of
extraction for flavonoids increased. In their research work
they used ethanol, methanol and acetone as solvent to de-
termine the flavonoid contents in ginger flowers, leaves and
rhizome. According to their outcomes, leaves have the
highest flavonoid contents as 5.5 ± 0.54 to 7.05 ± 1.65 mg/g
in ethanol, 4.70 ± 0.55 to 6.20 ± 1.7 mg/g in methanol and
4.54 ± 0.64 to 6.01 ± 1.65 mg/g in water acetone extract. For
thegingerflower,thevaluesofflavonoidswere3.60±0.12
to 4.40 ± 0.57 mg/g, 3.40 ± 0.13 to 3.80 ± 0.12 mg/g and
3.23 ± 0.12 to 3.70 ± 0.15 mg/g in ethanol, methanol and
acetone extract. The lowest flavonoids were observed in
ginger rhizome that were 1.30 ± 0.12 to 1.70 ± 0.49 mg/g in
ethanol, 0.83 ± 0.14 to 0.98 ± 0.14 m/g in methanol and
Table 2 Means for TPC, Flavonoids and Flavonols of ginger extract
Treatments Ginger Part Means
Rhizome Leaves Flower
TPC
mg GAE/100 g
Methanol 430.72 ± 16.80 645.26 ± 25.17 585.60 ± 22.84 533.86 ± 21.60
b
Ethanol 650.44 ± 27.32 780.56 ± 32.78 630.48 ± 26.45 687.16 ± 28.86
a
Water 297.88 ± 10.43 421.52 ± 14.75 325.50 ± 11.39 348.30 ± 12.19
c
Means 459.68 ± 18.39
c
615.78 ± 24.63
a
513.86 ± 20.55
b
Flavonoids
mg/100 g
Methanol 234.06 ± 9.13 246.98 ± 9.63 226.36 ± 8.83 235.80 ± 9.20
b
Ethanol 239.52 ± 10.06 253.56 ± 10.65 243.12 ± 10.21 245.40 ± 10.31
a
Water 218.34 ± 7.64 239.02 ± 8.37 228.68 ± 8.00 228.68 ± 8.00
c
Means 230.64 ± 9.23
b
246.52 ± 9.86
a
232.72 ± 9.31
b
Flavonols
mg/100 g
Methanol 37.48 ± 1.56 42.96 ± 1.60 40.12 ± 1.58 40.18 ± 1.58
b
Ethanol 43.38 ± 1.74 49.54 ± 1.74 45.98 ± 1.84 46.30 ± 1.73
a
Water 32.24 ± 1.40 38.06 ± 1.43 36.38 ± 1.41 35.56 ± 1.39
c
Means 37.70 ± 1.62
c
43.52 ± 1.52
a
40.82 ± 1.62
b
Means carrying same letters do not differ significantly
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0.741.02 to 0.90 ± 0.16 mg/g in acetone extract. Recently,
Amir et al. [34] depicted that ginger leaves have 0.84 ±
0.03% flavonoids (w/w) in dry form.
Flavonol contents
The statistical analysis revealed that the solvent as well
as the part of ginger commodity have significant effect
on the flavonol content however, the interaction of part
and solvent proved non-momentous effect on flavonols.
The values regarding the flavonols contents (Table 2)
depicted that the maximum flavonols were observed in
ethanol extract as 46.30 ± 1.73 mg/100 g however, the
minimum value was observed in water based extracts as
35.56 ± 1.39 mg/100 g. similarly, the highest value of fla-
vonols was calculated in ginger leaves (43.52 ± 1.52 mg/
100 g) followed by ginger flowers (40.82 ± 1.62 mg/100 g)
and ginger rhizome (37.70 ± 1.62 mg/100 g).
Amid all the herbs and spices, ginger has maximum
antioxidant ability owing to the presence of a number of
antioxidants that further comprised of flavonoids and
flavonols. The results of present investigation were in
harmony with the conclusions of Sultana and Anwar,
[36] who suggested that the flavonol content of ginger
14.9 ± 0.6 mg/g among which the most abundant was
kaempfherol as 11.9 ± 0.4 mg/g. Following them, Gha-
semzadeh et al. [28] worked on the flavonols content of
ginger and reported that the ginger has a number of fla-
vonols present in different parts of commodity. A few
such as epicatechin and rutin are light dependent and
their concentration increased with increased intensity of
light on leaves as well as flowers. However, naringenin is
present in very minute quantity in different parts of
ginger.
Moreover, Naeem et al. [37] depicted that the ethanol
extract of ginger leaves possessed 3.36 ± 0.3 mg/g of
flavonols among which myricetin, quercetin and kaempf-
herol were most important and present as 2.04 ± 0.3,
0.97 ± 0.3 and 0.35 ± 0.3 mg/g accordingly. They further
concluded that by increasing the concentration of etha-
nol from 50 to 80% the flavonol quantity gradually in-
creased as the total flavonols increased to 46.18 ± 0.2
mg/g with increased ratio of myricetin (42.6 ± 2.3 mg/g),
quercetin (4.9 ± 1.4 mg/g) and kaempfherol (91.68 ± 0.9
mg/g). However, by further increasing the ratio to 90%
the flavonols contents decreased.
In vitro study
DPPH scavenging capacity assay
DPPH is stable, non-reactive radical that can be poten-
tial to adopt hydrogen ion or an electron and can trans-
form into stable free radical in the presence of ethanol
or methanol solution of DPPH. The DPPH assay is
mostly carried out to determine the antioxidant perspec-
tives that valued up to the phytochemical profiling
through free radical scavenging ability. In this context,
ginger rhizome, leaves and flower extracts were used to
determine their DPPH assay. The mean squares of
DPPH assay concluded that the part as well as solvent
has momentous effect on the DPPH assay however, their
interaction depicted non-significant effect. The mean
values for free radical scavenging ability of ginger
(Table 3) demonstrated that the DPPH assay was max-
imum in ethanol extract (65.30 ± 2.74%) after that
methanol extract (60.56 ± 2.36%) and water extract
(49.04 ± 1.72%). Among the various ginger parts, leaves
depicted maximum DPPH assay potential as 65.64 ±
2.63% and minimum were reported for ginger rhizome
52.76 ± 2.11%.
The outcomes of present investigation were in line
with the conclusions of Hinneburg et al. [21]and
Table 3 Means for DPPH, Antioxidant activity and FRAP assay of ginger extract
Treatments Ginger Part Means
Rhizome Leaves Flower
DPPH % Methanol 57.82 ± 2.25 68.16 ± 2.66 55.70 ± 2.17 60.56 ± 2.36
a
Ethanol 51.10 ± 2.15 75.54 ± 3.17 69.26 ± 2.91 65.30 ± 2.74
b
Water 49.36 ± 1.73 53.22 ± 1.86 44.54 ± 1.56 49.04 ± 1.72
c
Means 52.76 ± 2.11
c
65.64 ± 2.63
a
56.50 ± 2.26
b
Antioxidant Activity % Methanol 58.38 ± 2.28 70.42 ± 2.75 61.22 ± 2.39 63.34 ± 2.22
b
Ethanol 72.46 ± 3.04 77.88 ± 3.27 69.56 ± 2.92 73.30 ± 3.08
a
Water 51.32 ± 1.80 56.60 ± 1.98 53.84 ± 1.88 53.92 ± 2.10
c
Means 60.72 ± 2.43
b
68.32 ± 2.73
a
61.54 ± 2.46
b
FRAP (μmole TE/g) Methanol 95.40 ± 3.72 100.18 ± 3.91 98.84 ± 3.85 98.14 ± 3.83
ab
Ethanol 99.52 ± 4.18 105.72 ± 4.44 102.62 ± 4.31 102.62 ± 4.28
a
Water 92.54 ± 3.24 97.46 ± 3.41 94.58 ± 3.32 94.86 ± 3.32
b
Means 95.82 ± 3.83
b
101.12 ± 4.04
a
98.68 ± 3.95
ab
Means carrying same letters do not differ significantly
Tanweer et al. Clinical Phytoscience (2020) 6:12 Page 6 of 12
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
Stoilova et al. [22] who reported that the DPPH assay
of different parts of ginger resulted as 90.1% when 9
mg/mL of DPPH solution was used. Similarly, Wei
and Shibamoto, [38] reported that the ginger oil ex-
tracted from ginger flowers concluded as 50% inhabit-
ation at the concentration of 200 μg/mL. Moreover,
Qusti et al. [25] suggested that moisture content of
ginger has strong effect on the DPPH assay as the
value increased in dried form as compared to fresh
ginger due to the intermediate bonding of water mol-
ecules with antioxidant moieties.
One of their peers, El-Ghorab et al. [27]determined
that the ginger essential oil extracted from green gin-
ger parts exhibits 83.03% DPPH assay @ 240 μg/mL.
Furthermore, Ghasemzadeh et al. [28] did their re-
search work on the DPPH assay of different parts of
ginger and concluded that the ginger flowers depicted
free radical scavenging activity in the range of
48.22 ± 1.19 to 41.41 ± 0.51% however, in ginger leaves
the DPPH assay was observed between 56.36 ± 0.97 to
51.12 ± 1.65% and 32.85 ± 0.57 to 31.45 ± 1.49% for
ginger rhizome. They further reported that after ma-
turity level, the DPPH assay of ginger rhizome in-
creased and the free radical scavenging ability of
leaves decreased because of molecules movements
from leaves to rhizome as main edible part of ginger
crop.
Following them, Lu et al. [39] proved that the
DPPH assay of dried ginger is up to 32.38 ± 1.42%.
At the same moment, Ali, [40] counted that the
DPPH assay of ginger in ethanol extract ranged up
to 79%. Furthermore, Mariutti et al. [41]reported
that ginger rhizome showed 7.8% DPPH assay how-
ever, for ginger flower the value was 19%. Recently,
Kubra et al. [42] anticipated that the aqueous ex-
tract of ginger has 42.80% free radical scavenging
ability that has quite resemblances with the findings
of current investigation.
Antioxidant activity (AA)
The statistical analysis proved that the antioxidant activ-
ity for ginger extracts has significantly affected by the
type of solvent and type of ginger part whilst, their inter-
action proved non-momentous effect on the antioxidant
activity. The mean values regarding the antioxidant po-
tential of ginger extracts (Table 3) demonstrated that the
maximum antioxidant activity was observed in ethanol
extract (73.30 ± 3.08%) followed by methanol extract
(63.34 ± 2.22%) and water extract (53.92 ± 2.10%). Re-
garding the part of ginger crop, the leaves revealed high-
est antioxidant activity as 68.32 ± 2.73% tackled by
flower (61.54 ± 2.46%) and rhizome (60.72 ± 2.43%).
The findings of current investigation were in agree-
ment with the research work of Stoilova et al. [22] who
suggested that the antioxidant activity of ginger is
temperature dependent. Purposely, they prepared the ex-
tracts at two different temperatures 37 °C and 80 °C and
incubated for 4 days. After the given time period, they
concluded that the extract prepared at 37 °C showed
62.5% antioxidant activity even @ 0.02% however, the
extract prepared at 80 °C didn’t impart any effect on the
antioxidant activity. Following them, El-Baroty et al. [43]
concluded that the antioxidant activity of ginger essen-
tial oil ranged up to 66.5%.
Nevertheless,KaurandKapoor,[19]determinedthe
antioxidant activity of ginger leaves and concluded
that the ethanol extract of ginger leaves showed
71.8% ability to bleach beta-carotene however, in
methanol the antioxidant activity of ginger leaves re-
duced to 65.0%. Another group of researchers, Eleazu
et al. [31] determined the antioxidant activity of gin-
ger and reported that the ethanol extract of ginger
has the ability to bleach the beta-carotene and alpha-
linolenic acid in the range of 75.22 to 94.28%, with
condition that the extracts should be prepared with
250 g of ginger.
Ferric reducing antioxidant potential (FRAP)
The ferric reducing antioxidant potential is the ability of
any compound to reduce ferric ion via the addition of
hydrogen removed from phenolic compound. The avail-
ability of reducing agents along with the position as well
as number of the hydroxyl groups also have influence in
the reduction procedure to enhance the antioxidant pro-
cedure. For FRAP assay, the statistical analysis proved
that both, the type of solvent and part of ginger crop
have momentous effect however, their interaction
depicted non-significant effect on the FRAP assay. The
mean values of FRAP (Table 3) illustrated that ginger
leaves revealed maximum FRAP potential as 101.12 ±
4.04 μmole TE/g followed by flower as 98.68 ± 3.95
μmole TE/g and rhizome extract (95.82 ± 3.83 μmole
TE/g). From solvent type, maximum FRAP ability was
observed in ethanol extract (102.62 ± 4.28 μmole TE/g)
as compared to methanol extract (98.14 ± 3.3 μmole TE/
g) and water extract (94.86 ± 3.32 μmole TE/g).
The results of present research work were in line with
the findings of Liu et al. [44] who reported that the anti-
oxidant FRAP potential of ethanol extract of ginger was
0.806 mmole of ferric (g). Similarly, El-Ghorab et al. [27]
did their research work on the antioxidant potential of
ginger and concluded that the FRAP assay is dependent
on the concentration of ginger in extract either in fresh
or dry form and increased the presence of phenolic com-
pounds hence, increased the absorbance for FRAP assay.
Moreover, Sanwal et al. [45] concluded that diploid and
tetraploid ginger clones have different FRAP potential.
They further reported that the diploid has higher ferric
Tanweer et al. Clinical Phytoscience (2020) 6:12 Page 7 of 12
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
reducing antioxidant power s compared to tetraploids.
According to their findings, the diploid ginger has FRAP
assay between 4.28 to 4.86 μg/g however, FRAP assay of
tetraploid ginger clone ranged from 4.60 to 5.19 μg/g.
Another group of scientists, Ghasemzadeh et al. [28]
worked on the FRAP assay of different parts of ginger
and reported that the maximum FRAP assay was ob-
served in ginger leaves as 680.68 ± 18.38 to 767.2 ±
41.53 μmol Fe (II)/g. The yellowish green part of ginger
crop (flowers) has lower ferric reducing antioxidant
power and ranged between 537.94 ± 37.30 to 579.6 ± 61.
μmol Fe (II)/g however, the minimum FRAP assay was
observed in ginger rhizome that varied from 368.27 ±
23.43 to 376.94 ± 50.97 μmol Fe (II)/g. Similarly, Pawar
et al. [35] supported the findings of Ghasemzadeh et al.
[28] and concluded that the ferric reducing antioxidant
power of different parts of ginger crop changed with the
changings in environmental conditions, age and variety.
Moreover, Lu et al. [39] investigated the FRAP assay of
ginger and concluded that the FRAP value was 157.95 ±
2.2 μmole TEAC/g. Nonetheless, Maizura et al. [33] de-
termined the FRAP assay of fresh ginger juice and re-
ported that the value was 26.2 μmole Fe/g. One of their
peers, Kruawan and Kangsadalampai, [46] who elabo-
rated that the aqueous extract of fresh ginger has stron-
gest FRAP ability as 1030.5 ± 11.49 μmol/g.
ABTS assay
ABTS is a reaction that take place between the
ABTS reagent and persulphate that in the end pro-
duce blue color. For the sample extract prepared
with any organic solvent, it produces a pre-formed
radical that further reduced to ABTS depending
upon the concentration of sample used to prepare
that extract. Following the same principle for the
ABTS assay of ginger extracts, the results proved
that both the type of solvent and part of ginger
imparted significant effect on the ABTS assay how-
ever, their interaction didn’t affect ABTS assay
significantly. The mean values (Table 4)ofABTS
assay suggested that maximum antioxidant potential
in the form of ABTS was observed by ethanol ex-
tract of ginger leaves (118.43 ± 4.97 μmol TE/g). The
ginger leaves proved more antioxidant power
(101.02 ± 4.04 μmol TE/g) over and above to flowers
(88.30 ± 3.53 μmol TE/g) and rhizome (83.47 ±
3.34 μmol TE/g). From the solvent side, ethanol
proved maximum ABTS assay as 105.90 ± 4.45 μmol
TE/g however, minimum was observed in water ex-
tract as 80.68 ± 2.84 μmol TE/g.
The results of present investigation were in har-
mony with the findings of Puengphian and Sirichote,
[23] who performed their research work on the ABTS
assay of fresh as well as dried ginger and concluded
that the extract prepared with dried ginger showed
maximum ABTS assay (169.06 ± 3.96 μmol TE/g) as
compared to fresh ginger extract in which the ABTS
assay were depicted as 403.71 ± 7.24 μmol TE/g.
Moreover, Hossain et al. [47]workedonthemetha-
nol extract of ginger prepared with 80% methanol
and centrifuge for 15 min @ 3000 rpm and reported
that the ABTS assay in ginger extract were 406.29 ±
17.35 g TE/100 g. One of their peers, Lu et al. [39]
performed their research work on the methanol ex-
tract of ginger (60%) prepared at 35 °C for 15 min @
1500 rpm and then investigated its ABTS assay. Ac-
cording to their findings, the dried ginger methanol
extract showed 75.66 ± 1.15 μmol TE/g antioxidant po-
tential. Recently, Mariutti et al. [41] determined the
ABTS potential of ginger in ethanol extract and con-
cluded that the ABTS assay of ginger ethanol extract
was 23.0 ± 0.3 mM/g ABTS reagent.
Metal chelating potential
The lipid peroxidation is initiated in the body by the
presence of metal ions that further increased the
process of lipid peroxidation by forming free radicals.
The metal chelating potential provides the results
Table 4 Means for ABTS and metal chelating assay of ginger extract
Treatments Ginger Part Means
Rhizome Leaves Flower
ABTS
μmol TE/g
Methanol 81.54 ± 3.18 92.88 ± 3.62 84.24 ± 3.29 86.22 ± 3.36
b
Ethanol 96.26 ± 4.04 118.43 ± 4.97 103.00 ± 4.33 105.90 ± 4.45
a
Water 72.64 ± 2.54 91.74 ± 3.21 77.66 ± 2.72 80.68 ± 2.84
c
Means 83.47 ± 3.34
c
101.02 ± 4.04
a
88.30 ± 3.53
b
Metal Chelating % Methanol 15.02 ± 0.53 31.36 ± 1.10 18.48 ± 0.65 21.62 ± 0.76
b
Ethanol 17.98 ± 0.76 35.16 ± 1.48 21.32 ± 0.90 24.82 ± 1.04
a
Water 13.86 ± 0.54 29.54 ± 1.15 16.30 ± 0.64 19.90 ± 0.78
c
Means 15.62 ± 0.62
b
32.02 ± 1.28
a
18.70 ± 0.78
b
Means carrying same letters do not differ significantly
Tanweer et al. Clinical Phytoscience (2020) 6:12 Page 8 of 12
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
about the antioxidant potential of any compound
along with the anti-radical properties. The absorbance
for the metal chelating potential is inversely propor-
tional to the metal chelating power as high absorb-
ance indicated low metal chelating potential and vice
versa. The ability of free radicals to start the process
can be delayed by the chelation of metal. Therefore,
metal chelating potential is considered as a mandatory
test to determine the antioxidant potential of any bio-
active compound. The statistical analysis regarding
the metal chelating potential proved that type of solv-
ent and part of crop both have significantly affected
the metal chelating potential however, the aspect
remained non-momentous for their interaction. The
values (Table 4) relating to metal chelating potential
of ginger revealed that the ethanol extract showed
maximum metal chelating potential (24.82 ± 1.04%)
followed by methanol extract (21.62 ± 0.76%) and
water extract (19.90 ± 0.78%). From the part of ginger
commodity, ginger leaves showed maximum metal
chelating ability s 32.02 ± 1.28% as compared to gin-
ger flower and ginger rhizome as 18.70 ± 0.78 and
15.62 ± 0.62%, respectively.
The findings of current investigation were in line
with the results of Hinneburg et al. [21]whoper-
formed their research work on the metal chelating
potential of ginger extract and concluded that the
ginger extracts prepared with different concentra-
tions have different ferric ion chelation potential
that varied from 16.0 ± 0.17 to 21.6 ± 0.51%. They
further reported that the metal chelating potential
of ginger is dependent upon the concentration of
ginger taken to produce extract. Following them,
Lee et al. [48] resulted that the metal chelating po-
tential of ginger extract is near about 52% when the
extract is prepared with g/mL concentration. More-
over, Zhang et al. [49] used three different type of
solvent for the preparation of ginger extracts as al-
kaline, acid and water extract. According to their
outcomes, the metal chelating potential was max-
imum in alkaline extract (57.1 ± 1.83%) tracked by
water extract (56.8 ± 0.12%) and acid extract (35.4 ±
0.56%). Likewise, Chen et al. [50]workedondried
ginger leaves and reported that the gingerol content
of leaves have the ability to withstand with temperature
however, in ginger rhizome gingerol transformed into sho-
gaol by the application of het during drying process as a
result of thermal degradation. They advocated that the
metal chelating potential of dried ginger leaves was 73%
however, in dried ginger rhizome this metal chelating po-
tential was less than 10% against EDTA as standard. They
further suggested that moisture content of ginger have ef-
fect on the metal chelating potential of bioactive moieties
of ginger.
HPLC assessment
HPLC quantification is a mandatory step for the
quantification of resultant extracts to further
categorizethemaccordingtothepresenceofbio-
active compounds. Depending upon the results of
phytochemical screening and in vitro antioxidant
assay, ethanol extract of all three parts, rhizome,
leaves and flower were selected for the qualitative as
well as quantitative analysis of phytoceutics as gin-
gerol. The HPLC graded gingerol standard was used
and the presence of gingerol in different ginger parts
was ensured by comparing the peak area of sample
and standard along with the retention time.
HPLC quantification of 6-gingerol
The quantification of 6-gingerol through High perform-
ance liquid chromatography (HPLC) revealed that ginger
parts have 4 times more concentration of gingerol as
compared to other bioactive moieties. The resultant
peaks of ginger rhizome, leaves and flower obtained by
HPLC were inferred with the peaks of standard for the
peak area, retention time and spectral exploration. The
HPLC quantification of ginger parts (rhizome, leaves
and flower) in Table 5, proved that highest gingerol con-
tent were present in ethanol extract of ginger leaves
(4.19 mg/g) followed by ethanol extract of ginger flower
(2.87 mg/g) and ethanol extract of ginger rhizome (1.03
mg/g). It was also discovered from phytochemical profil-
ing that ethanol extract was the most efficient solvent to
solubilize the essential oils of ginger crop owing to its
polar and organic nature as compared to methanol and
water.
Gingerol provides the highly purified essence to
the ginger and it can be extracted by using many
protocols such as solvent extraction and steam distil-
lation [6,51,52]. Ginger extract isolated by ether
technique is then purified and quantified by HPLC
and being used in pharmacy, aromatherapy along
with seasoning and beverages. Purposely, Schwertner
and Rios, [53] depicted the amount of gingerol after
characterization and quantification pf gingerol via
HPLC in beverage with special reference to tea. Ac-
cording to their findings, the dried ginger parts have
more than 9.5% gingerol as compared to fresh por-
tions. They further suggested that the dried green
part of ginger has more gingerol as compared to
Table 5 HPLC quantification for gingerol (mg/g) in ginger parts
ethanol extracts
Part of ginger crop Concentration (mg/g of dry matter)
Rhizome 1.03
Leaves 4.19
Flower 2.87
Tanweer et al. Clinical Phytoscience (2020) 6:12 Page 9 of 12
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
yellow part owing to the presence of heat stable bio-
active compounds.
Following them, Puengphian and Sirichote, [23]didtheir
research work on the antioxidant profiling and quantifica-
tion of ginger and concluded that the dried ginger has
18.81 mg/g of gingerol however, in fresh ginger the content
ranged up to 104 to 965 μg/g. The dried part has lesser
amount of gingerol with higher antioxidant properties [54].
The ginger in fresh form almost contain 92% of bioactive
moieties however, the major part is contributed towards
zingiberne, arcurmene, β-bisabolene and subsequently gera-
nial in the range of 28.6, 5.6, 8.5 and 5.8%, accordingly [55].
According to literature, 6-gingerol has highest rank in gin-
ger ranging from 1.030 to 3.046 mg/g of ginger rhizome.
Over and above to 6-gingerol, 8-gingrol also exist in ginger
whilst in lesser quantity ranging from 0.078–0.0425 mg/g
[45]. Their findings were further elaborated by another
group of scientists, Pawar et al. [35]whosuggestedthatthe
gingerol concentration of water extract of dried ginger var-
ied from 1.17 t0 2.08 mg/g.
At the same moment, Wohlmuth et al. [56]investi-
gated the gingerol content from 12 different clone of
ginger crop. During the quantification of gingerol, the
used acetonitrile and water combination as mobile
phase for the verification of methanolic extract of
ginger and concluded that the 6-gingerol content in
methanol extract were 2.10 mg/g however, in minutes
quantities 8-gingerol and 10-gingerol were also
present. Overall the quantity of bioactive compound
in dried ginger was 29.2% [57]. After that, Hasan
et al. [58] worked on the preparation and quantifica-
tion of methanol and hexane-based ginger extracts
and reported that the methanol extract gave higher
peak as 25% however, it was 235 for hexane extract
whilst, the retention time was same 738 min. Simi-
larly, Silva et al. [59] did their research work on
HPLC quantification of methanolic extract of dried
ginger crop powder by using water and acetonitrile as
mobile phase in C
18
column having flow rate @1 mL/
min and claimed that the amount of gingerol in
methanolic extract of ginger was 30 mg/g. one of their
peers, Rafi et al. [60] worked on different parts of
ginger crop. In their research work, they extracted
the ginger extracts via ultra-sonication and then
quantified through HPLC. According to their results,
the 6-gingerol content in ginger rhizome were 2.98 ±
0.06 mg/g although, in ginger leaves the gingerol con-
tent were 18.83 ± 0.28 mg/g when the mobile phase
used was comprised of acetonitrile. In this context,
Jiang et al. [61] quantified the ginger profile and re-
ported that the isolated ginger extract has 1.93–3.57
mg/g of gingerol content that is responsible for its
strong and unique pungency required in spices and
food products to enhance taste as well as flavor.
HPLC Peaks:
Gingerol Std 500 ppm
Ginger Rhizome Extract
Ginger Leaves Extract
Ginger Flower Extract
Conclusion
The finding of present investigation concluded that gin-
ger leaves have maximum antioxidant potential as com-
pared to ginger flowers and rhizome. The gingerol
present in ginger leaves have heat sensitive properties
and did not decompose into shogaol on heat treatment
during the process of drying. Furthermore, among the
solvents, ethanol has the strongest ability to hold the
bioactive ingredients as compared to methanol and
water. Contemporary, it is the need of current era to de-
velop designer food products by the addition of ginger
leaves. It is also anticipating that green leaves and
flowers have the strong potential to be used in daily diet-
ary regime along with development of novel food
products.
Tanweer et al. Clinical Phytoscience (2020) 6:12 Page 10 of 12
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
Abbreviations
ABTS: 2, 2-azino-bis, 3-ethylbenzothiazoline-6-sulphonic acid; DPPH: 1,1-
diphenyl-1-picrylhydrazyl; EDTA: Ethylenediaminetetraacetic acid; FRAP: Ferric
reducing antioxidant power; HPLC: High Pressure Liquid Chromatography;
TE: Trolox Equivalent; TEAC: μmol trolox equivalent antioxidant capacity;
TPC: Total phenolic contents; TPTZ: 2,4,6-Tripyridyl-s-triazine 2,4,6-Tri (2-
pyridyl)-s-triazine
Acknowledgements
The authors are thankful to Functional and Nutraceutical Food Research
Section, National Institute of Food Science and Technology, University of
Agriculture, Faisalabad, Pakistan.
Conflict of interest
The authors declare no conflict of interest.
Authors’contributions
ST, TM and SZ designed the project under the supervision of AS, however,
ZA helped in the extraction method. SA, TM and SZ performed all the tests
and prepared the manuscript. The author(s) read and approved the final
manuscript.
Funding
This research was partially supported by Higher Education Commission,
Pakistan under Pak-US Science and Technology Cooperation Program Phase.
IV (Project Grant No. 10/01/10–09/30/12), project entitled “Establishment of
Functional and Nutraceutical Food Research Section at the National Institute
of Food Science and Technology, University of Agriculture, Faisalabad,
Pakistan”.
Availability of data and materials
Not applicable.
Ethics approval and consent to participate
Ethics approval was provided by the head of the NIFSAT-UAF, Pakistan, by
reviewing the plans of Environmental Ethics Committee, UAF. The care of en-
vironment during experimentation were as per the instructions provided by
the committee and the university.
Consent for publication
Not applicable.
Competing interests
The authors declare that they have no competing interests.
Author details
1
National Institute of Food Science and Technology, University of Agriculture
Faisalabad, Faisalabad, Pakistan.
2
Department of Food Science and
Technology, The Islamia University of Bahawalpur, Bahawalpur, Pakistan.
3
Department of Food Science and Technology, Khawaja Fareed University of
Engineering and Information Technology, Rahim Yar Khan, Pakistan.
4
Department of Food Engineering, University of Agriculture Faisalabad,
Faisalabad, Pakistan.
5
College of Food Science and Technology, Henan
University of Technology, Zhenazhou, China.
6
UniLaSalle International
Campus de Rouen –Normandie Universite, 3 rue du Tronquer- CS 40118- F-
76134, Mont St Aignan cedex, France.
Received: 13 August 2019 Accepted: 11 February 2020
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