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Phenolic content, acute toxicity of Ajuga iva extracts and assessment of
their antioxidant and carbohydrate digestive enzyme inhibitory effects
F. Saad
a,
⁎, H.N. Mrabti
a
,K.Sayah
a
, A. Bouyahya
b
,N.Salhi
c
,Y.Cherrah
c
,FaouziElAbbes
a
a
Biopharmaceutical and Toxicological Analysis Research Team, Laboratory of Pharmacology and Toxicology, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco
b
Laboratory of Human Pathologies Biology, Departmentof Biology, Facultyof Sciences, and GenomicCenter of Human Pathologies, Faculty of Medicineand Pharmacy, MohammedV University in
Rabat, Morocco
c
Pharmacoepidemiology and Pharmacoeconomics Research Team, Laboratory of Pharmacology and Toxicology, Faculty of Medicine and Pharmacy, Mohammed V University of Rabat, Morocco
abstractarticle info
Article history:
Received 14 November 2018
Received in revised form 28 July 2019
Accepted 2 August 2019
Available online xxxx
Edited by L Verschaeve
The management of blood glucose level is the hallmark in the treatment of type 2 diabetes, and this may be
achieved through the inhibition of the digestive enzymes involved in carbohydrate metabolism. The aim of
this work is the investigation of phenolic compounds content, antioxidant activity and for the first time, the
in vitro anti-hyperglycemic potential of aerial part of Ajuga iva Schreber extracts through the inhibition of diges-
tive enzymes (α-amylase and α-glucosidase), responsible of the digestion of poly and oligosaccharides. Test for
total phenolic content showed that the methanol extract has the highest polyphenolic and flavonoid concentra-
tions with (65.3 mg GAEs/g extract and 132.6 mg REs/g extract). The methanol extract has also exhibited the
higher antioxidant activity compared to the aqueous extract in different tests with (IC
50
=0.187 ±0.016 mg/mL;
62.19±0.45 mg TE/g extract; 89.12±0.23 mg AAE/g extract) in DPPH, ABTS and FRAP tests, respectively. Ajuga
iva extracts exhibited a remarkable inhibitory activity against key digestive enzymes linked to type 2 diabetes,
with a more potent inhibitory effect against α-glucosidase and a considerable inhibition against α-amylase.
The results indicated also that the tested extracts are non-toxic with an LD
50
higher than 2 g/kg in female
Swiss mice.These results suggested that the phenolic compounds in A. iva extracts maybe behindthe antioxidant
and antidiabetic activities. However, further investigations regarding the bioactive compounds and their mech-
anisms of action are required for developing new natural drugs against diabetes-related hyperglycemia.
© 2019 SAAB. Published by Elsevier B.V. All rights reserved.
Keywords:
Ajuga iva
Phenolic compounds
Antidiabetic effect
Digestive enzymes
Antioxidant activity
1. Introduction
Type 2 diabetes mellitus (T2DM) is a metabolic disorder character-
ized by hyperglycemia, due to an absolute or relative lack of resistance
to insulin (Association, 2014). According to statistics published by the
International Diabetes Federation (IDF) in 2017, approximately 425 mil-
lion people suffered from diabetes mellitus in the world and it is esti-
mated to be 629 million by 2045 (International Diabetes Federation,
2017). Furthermore, prolonged hyperglycemia can induce the produc-
tion of excessive amounts of reactive oxygen species (ROS) in tissues
and cells. An oxidative stress can lead to the development of various
health problems in kidney, heart, eye, liver, and central nervoussystem,
and this progress can cause serious organ and physiologic system dam-
ages (Tangvarasittichai, 2015). One therapeutic approach to decrease
postprandial hyperglycemia is to retard and reduce the absorption of
ingested carbohydrates. The inhibition of digestive enzyme such as
α-amylase and α-glucosidase limits the process of carbohydrate
hydrolysis and absorption, and favors the control of the postprandial
hyperglycemia (Marmouzi et al., 2017; Mrabti et al., 2018; Sayah
et al., 2017). Commercially synthetic inhibitors (Acarbose, Miglitol,
Voglibose and Orlistat) are an effective way to control T2D (Tahrani
et al., 2016), but they can cause adverse health effects suchas flatulence,
diarrhea, hepatotoxicity, and abdominal pain to diabetic patients
(Chaudhury et al., 2017). In the context of the development of pharma-
ceutical agents to treat diabetes, the community’s attention has been di-
rected toward the search for novel effective agent extracted from
medicinal plants (Grover et al., 2002), which posses several bioactive
compounds belonging to the secondary metabolites such as polyphe-
nols, and alkaloids. Polyphenols, in particularly, flavonoids have espe-
cially antioxidant, anti-inflammatory, and antidiabetic effects
(Boussouf et al., 2017; Thibane et al., 2019). Indeed, the use of these
compounds as a combination therapy can play an important role for re-
ducing the dangerousness of pharmaceutical drugs, consequently, re-
duce their adverse effects. Antihyperglycemic plants have been used
in Moroccan folk medicine since ancient times; with more than 92 me-
dicinal plants used in tradition as complementary to treat diabetes
(Eddouks et al., 2002), among them Ajuga iva Schreber. This plant is a
part of the Lamiaceae family, popularly known as “Chendgoura,”has
been well-used as a treatment of various diseases including diabetes
South African Journal of Botany 125 (2019) 381–385
⁎Corresponding author at: Laboratoire de Pharmacologie et Toxicologie, Faculté de
Médecine et de Pharmacie, Mohammed V University in Rabat, BP 6203, Rabat Instituts,
Rabat, Morocco.
E-mail address: saadfettach.mar@gmail.com (F. Saad).
https://doi.org/10.1016/j.sajb.2019.08.010
0254-6299/© 2019 SAAB. Published by Elsevier B.V. All rights reserved.
Contents lists available at ScienceDirect
South African Journal of Botany
journal homepage: www.elsevier.com/locate/sajb
mellitus. In an ethnopharmacology survey carried out in Morocco
(Tahraoui et al., 2007), A. iva has been recognized for being among the
high-frequency plants uses. A large number of pharmacological studies
have been reported that Ajuga iva extract has an anti-inflammatory ac-
tivity (Taleb-Senouci et al., 2012) and protect against heart disease (El-
Hilaly et al., 2004). Furthermore, it is known that Ajuga iva has been
used as anthelmintic (Bellakhdar et al., 1991), antimicrobial, and anti-
fungal agents (Makni et al., 2013a). Some species from genus Ajuga
are used for the treatment of analgesia and fever (Pal and Pawar,
2011). However, to our best knowledge there are no reports in the liter-
ature concerning the enzymes inhibitory properties of this plant, which
make this study the first about inhibition of carbohydrate digestive en-
zymes using in vitro models by the selected specie. So, we decided to
build this work concerningthe evaluation of the in vitro inhibitory effect
of A. iva aqueous and methanol extracts against two enzymes linked to
T2DM (α-glucosidase and α-amylase) as well as their antioxidant activ-
ity by different tests and then evaluation of their acute toxicity in Swiss
mice.
2. Materials and methods
2.1. Standards and reagents
ρ-Nitrophenyl-α-D-glucopyranoside (pNPG), α-glucosidase from
Saccharomyces cerevisiae,α-amylase from Bacillus licheniformis, acar-
bose, Folin–Ciocalteu reagent, rutin, catechin, DPPH, ABTS, 6-hydroxy-
2,5,7,8- tetramethylchroman-2-carboxylic acid (Trolox), butylated
hydroxytoluene (BHT), and ascorbic acid were purchased from
Sigma–Aldrich (France). All other reagents and standards were of ana-
lytical reagent (AR) grade.
2.2. Plant material
The aerial parts of the plant Ajuga iva were collected during the
floweringperiod (March 2017) in Morocco, Taza, Oued Amlil, (a moun-
tainous area located between the Rif chain to the north and the Middle
Atlas to the south, latitude: 331 m). The plant material was identified
and authenticated (Voucher Specimen: RAB 110960) by Pr. Mohammed
Sghir TALEB of the Botany Department of the ScientificInstituteof
Rabat, University of Mohammed V Rabat, Morocco. Plant material was
dried in the shade at room temperature, powdered to achieve a mean
particle size, and kept in the dark until future use.
2.3. Preparation of extracts
2.3.1. Preparation of aqueous extract
The powder was extracted by infusion as described in Moroccan folk
medicine. Briefly, 50 g of plants powders were infused in 500 mL of dis-
tilled water for a period of 30 min, then filtered and evaporated under
vacuum at 50 °C using a rotary evaporator. The recovered extract was
frozen and lyophilized to remove all traces of water.
2.3.2. Preparation of methanol extract
The powder (50 g) was extracted by maceration using methanol 90%
(500 mL) at room temperature with agitation for 24 hours. After filtra-
tion, the extracting solvent was removed using rotary evaporator at 41 °C.
2.4. Determination of phenolic contents
2.4.1. Total phenolic content
TPCs were determined by using the Folin–Ciocalteu reagent method
as described by Spanos (Spanos and Wrolstad, 1990) with some modi-
fications. A standard curve was evaluated using gallic acid concentra-
tions ranging from 0.25 to 50 μg/mL. Firstly, 2.5 mL of 10% (v/v)of
Folin–Ciocalteu reagent were mixed with 0.5 mL of sample solution.
The reaction was incubated at 45 °C for 30 min after the addition of
4 mL of 7.5% (w/v)Na
2
CO
3
. The absorbance against blank was deter-
mined at 765 nm. TPCs were expressed as mg gallic acid equivalents
per gram of dry weight of extract (mg GAE/g extract).
2.4.2. Total flavonoid content
TFCs were assessed according to thealuminum chloride colorimetric
method as described by Dewanto et al. (2002).Briefly, 1 mL of sample
were added to 0.3 mL of NaNO
3
(5%), then 0.3 mL of 1% (w/v)AlCl
3
was added 5 min later. After 6 min, 2 mL of 1 M NaOH were added;
this solution was mixed well and allowed to stand for 30 min at room
temperature. The absorbance was measured at 510 nm. TFCs were
expressed as mg Rutin equivalent per gram of dry weight of extract
(mg RE/g extract).
2.4.3. Total tannin content
The method described by Julkunen-Tiitto (1985) is used to deter-
mine the condensed tannins content. Briefly, an aliquot (50 μL) of
each extract or standard solution was mixed with 1.5 mL of 4% vanillin
(prepared with MeOH), then 750 μL HCl (12 M) was added. The well-
mixed solution was incubated at ambient temperature in the dark for
20 min. The absorbance was read after at 500 nm. Catechin (50–500
μg/mL) was used to make the standard curve and the results were
expressed as mg Catechin equivalents per gram of extract dry weight
(mg CE/g extract).
2.5. Evaluation of the antioxidant activity
2.5.1. DPPH radical scavenging assay
The method using the stable free radical 2,2-diphenyl-1-picrylhyd-
razyl (DPPH) is based upon the reduction of DPPH free radical (Huang
et al., 2011). The extracts were solubilized in a methanol solution of
DPPH (0.02 mM). The reaction mixture was thoroughly vortexed and
incubated in the dark at room temperature for 30 min. Reduction in
the absorbance of the mixture was measured at 517 nm, using BHT as
a positive control. Scavenging of DPPH radicals was calculated using
the following equation:
DPPH (%) = [(Abs
DPPH
–Abs
Sample
)/Abs
DPPH
]∗100
Where Abs
DPPH
is the absorbance of D PPH radical and Abs
sample
is the
absorbance the DPPH radical in the presence of extract/control. Scav-
enging activity in this assay was expressed as IC
50
, which represents
the concentration of the extract required to inhibit 50% of the free rad-
ical scavenging activity.
2.5.2. Trolox equivalent antioxidant capacity (TEAC) assay
The antioxidant capacity assay was carried out using ABTS radical
cation decolorization assay as described by Tuberoso et al. (2013).
ABTS
+
radical were generatedby oxidation of ABTS with potassium per-
sulfate. The blue-green ABTS was produced through the reaction be-
tween 2 mM ABTS and 70 mM potassium persulfate in water. The
mixture was left to stand at room temperature in the dark for 12–16 h
before use. The ABTS
+
solution as diluted with methanol to an absor-
bance of 0.700 ± 0.005 at 734 nm. Then 2 mL of diluted ABTS solution
were mixed with 100 μL of plants extracts and absorbance was mea-
sured after 1 min incubation at room temperature. A standard curve
was obtained by using Trolox standard solution and the antioxidant ac-
tivities of samples were expressed as TEAC values. The results were
represented as Trolox equivalent per gram of extract dry weight
(mg TE/g
extract
).
2.5.3. Ferric reducing power assay (FRAP)
The ferric ion (Fe
3+
) reducing power assay was carried out accord-
ing to the procedure described by Amarowicz et al. (2004), with slight
modifications. Briefly, 1 mL of the extracts were mixed with 2.5 mL of
0.2 M sodium phosphate buffer (pH 6.6) and 2.5 mL of 1% potassium
382 F. Saad et al. / South African Journal of Botany 125 (2019) 381–385
ferricyanide. The mixture was incubated in a boiling water bath at 50 °C
for 20 min. After cooling, 2.5 mL of 10% trichloroacetic acid was added
and centrifuged at 3000 rpm for 10 min. Finally, 2.5 mL of the superna-
tant were mixed with 2.5 mL distilled water and 0.5 mL FeCl
3
solution
(0.1%, w/v). The absorbance was measured at 700 nm and the results
were expressed as ascorbic acid equivalent per gram of extract dry
weight (mg AAE/g extract).
2.6. Enzyme inhibitory activities
2.6.1. α-Glucosidase inhibition assay
The α-glucosidase inhibitory activity was performed in PBS (0.1 M
KH
2
PO
4
–K
2
HPO
4
, pH 6.7), using ρ-nitrophenyl-α-D-glucopyranoside
(ρNPG) as a substrate according to the method described by Kee et al.
(2013) with some modifications. All tested extracts were dissolved in
PBS to a series of different concentrations. Briefly, a mixture of 150 μL
of the samples and 100 μL of PBS containing the enzyme α-glucosidase
solution (0.1 U/mL) were incubated at 37 °C for 10 min. Then, 200 μL
ρ-nitrophenyl-α-D-glucopyranoside (1 mM) were added to the mix-
ture to initiate the reaction. After further incubation at 37 °C for
30 min, 1 mL Na
2
CO
3
(0.1 M) were added and the absorbance was mea-
sured at 405 nm. The results were expressed as percentage inhibition
and calculated using the following formula:
Inhibition (%) = [1 −(A
sample
–A
b sample
)/(A
control
–A
bcontrol
)] ∗100
Where A
control
refers to the absorbance of control (enzyme and
buffer); A
bcontrol
refers to the absorbance of control blank (buffer with-
out enzyme); A
sample
refers to the absorbance of sample (enzyme and
inhibitor); and A
b sample
is the absorbance of sample blank (inhibitor
without enzyme). Acarbose was used as positive control.
2.6.2. α-amylase inhibition assay
The α-amylase inhibitory potential was performed by reactingdiffer-
ent concentrationsof extracts with α-amylase and starchsolution, as de-
scribed by Hashim et al. (2013) with some modifications. Samples
solution(250 μL) weremixed with 250 μL of0.02 M PBS (pH 6.9) contain-
ing the α-amylaseenzyme (240 U/mL)and incubatedfor 20 min at 37 °C.
Soluble starch (1%, PBS 0.02, pH 6.9) wasadded to the mixture and fur-
ther incubated at 37 °C for 20 min. The reaction was stopped by adding
250 μL of dinitrosalicylic acid andthe incubation of the solution at 90 °C
in a water bath for 10 min. The cooled reaction mixture was diluted
with 1 mLdeionized waterand the absorbance was measured at 540 nm.
The α-amylase inhibitory activity was expressed as a percentage in-
hibition, and the IC
50
values were determined. Acarbose was used as a
positive control.
2.7. Acute oral toxicity testing
Acute oral toxicity of extracts was tested on Swice females mice ac-
cording to the instructions of the Organization for Economic Testing of
Chemicals no 423 (Botham, 2004). After fasting overnight, six mice
from each group were received a single oral dose of 2000 mg/kg body
weight (BW) of each extract. The animals were observed for gross
behavioral, neurological, autonomic and toxic sings for 5 hours after ex-
tracts/vehicle administration and daily for 2 weeks. Food consumption
and body weight were recorded daily for 14 days. Untreated control
group received distilled water as vehicle was also assayed.
2.8. Statistical analysis
All the experiments were carried out in triplicate. The data were de-
scribed as the mean ± standard error of mean and expressed by one-
way analysis of variance (ANOVA), followed by Duncan's new analysis
to identify significant differences between means using Multiple
Range Test (p b0.05). All statistical analysis was determined using
GraphPad Prism 6.
3. Results and discussions
Total phenolics (TPC), flavonoid (TFC), and condensed tannins (TCC)
contents of the aqueousand methanol extracts of Ajuga iva are summa-
rized in Table 1. As listed, the methanol extract contained a remarkably
high TPC (65.3 mg GAEs/g extract), TFC (132.6 mg REs/g extract), and
TCC (13.23 mg CEs/g extract). On the other hand, the aqueous extract
was found to be rich on polyphenols specially flavonoids, with a TPC
of (44.41 mg GAEs/g extract), (128.4 mg REs/g extract) respectively.
The results obtained in phenolic content studies in organic extracts of
A. iva revealed the presence of important charges of polyphenols and
flavonoids, with some variability between aqueous and methanol ex-
tract. This difference due certainly to the polarity of each solvent to en-
train phenolic compounds. In comparison with similar works, total
phenolics, and flavonoid of A. iva in this study were higher than those
obtained in the same species from other regions with a TPC of 16.5 mg
GAEs/g and TFC of 1.1 mg QEs/g in Makani’s study (Makni et al.,
2013b), a TPC of 46 mg GAEs/g extract in the study of Bendif et al.
(2017) and 50 mg GAEs/g extract (Bouyahya et al., 2016) and higher
also than those reported for the ethyl acetate extract of A. chamaepitys
(57.0 mg GAEs/g and 91.7 mg REs/g, respectively) (Jakovljevićet al.,
2015).
The different extracts were investigated for their antioxidant capac-
ity using three complementary tests: DPPH, ABTS radical scavenging ca-
pacity, and FRAP (Table 2). The results of DPPH test showed a dose-
dependent activity that can be evaluated by determination of IC
50
values. Low values of IC
50
indicate an important antioxidant activity.
As shown in Table 2, the extracts showed a considerable antioxidant ac-
tivity especially the methanol extract with (IC
50
=0.187± 0.016 mg/-
mL) and this was higher than the IC
50
obtained by infusion
(IC
50
=0.225 ±0.026 mg/mL). The antioxidant activity of these extracts
stayed lower than those of ascorbic acid (IC
50
=0.007± 0.001 mg/mL)
and BHT (IC
50
=0.029 ±0.006 mg/mL) used as positive controls. Ajuga
iva extracts have developed an important antioxidant activity in the
ABTS test, with a correlation to the antioxidant activity shown in the
DPPH test (Table 2). Ajuga iva methanol extract showed the highest an-
tioxidant ability (62.19 ± 0.45 mg TE/g extract) as compared with the
aqueous extract (49.72 ± 0.24 mg TE/g extract). Moreover, in the
FRAP method, the highest reducing power was interestingly observed
Table 1
Total phenolic, flavonoids and condensed tannins contents of different extracts from A. iva. Data are expressed as mean ± SD (n = 3).
Aqueous extract Methanol extract
TPC (mg GAE/g extract) TFC(mg RE/g extract) TCC (mg CE/g extract) TPC(mg GAE/g extract) TFC(mg RE/g extract) TCC (mg CE/g extract)
Ajuga iva 44.41 ± 0.22 128.4 ± 2.14 10.76 ± 1.15 65.3 ± 2.11 132.6 ± 0.24 13.23 ± 1.15
TPC: total phenolic content
TFC: total flavonoid content
TCC: total condensed tannins
mg RE/g extract: mg of Rutin equivalent per gram of extract
mg GAE/g extract: mg Galic Acid equivalent per gram of extract
mg CE/g extract: mg Catechin equivalent per gram of extract
383F. Saad et al. / South African Journal of Botany 125 (2019) 381–385
also in the methanol extract (89.12 ± 0.23 mg AAE/g extract), followed
by the aqueous extract (78.8 ± 1.18 mg AAE/g extract). In these tests,
A. iva revealed interested antioxidants effects with minor differences
between the two tested extracts and different methods used to study
the antioxidant activity. Ajuga iva extracts showed the highest antioxi-
dant activity compared with the reported studies of Medjeldi on the
same species (Medjeldi et al., 2018)withanIC
50
=0.43 ± 0.03 mg/mL
and Movahhedin (Movahhedin et al., 2016)(IC
50
= 0.330 mg/mL)
using DPPH test. The antioxidant potential of methanol and aqueous ex-
tracts of our species in ABTS test were also greater compared to antiox-
idant activity of aqueous and ethanol extracts of A. chamaecistus,a
specie from the same genus, reported in Nasrin study (43.19 ± 1.04
and 39.41 ± 2.13 mg TE/g extract) using ABTS test (Movahhedin
et al., 2016). The antioxidant activity of A. iva methanol and aqueous ex-
tracts could be explained by the presence of important charges of phe-
nolic compounds like polyphenols, and flavonoids. Indeed, numerous
studies reported previously that phenolic compounds possess remark-
able antioxidants properties in vitro and in vivo systems (Granato
et al., 2018; Pang et al., 2018; Yuwang et al., 2018), and the correlation
between phenolic substances and antioxidant effects was established
in several previous studies (Cai et al., 2004; Djeridane et al., 2006).
Ajuga iva aqueous and methanol extracts were also tested for their
inhibitory activities against the enzymes α-glucosidase and α-
amylase. The obtained results are listed in (Table 3). As summarized,
the extract obtained by maceration with methanol exhibited the
greatest inhibition potential activity against α-glucosidase and
α-amylase, with an IC
50
= 0.130 ± 0.008 and 0.172 ± 0.012 mg/mL, re-
spectively (Table 3). The aqueous extract was less efficient against
α-glucosidase and α-amylase as compared to methanol extract, with
an IC
50
= 0.180±0.005 and 0.210 ± 0.003 mg/mL respectively. The
considerable inhibitory effects of A. iva extracts against the enzymes
α-glucosidase and α-amylase showed a correlation with antioxidant ac-
tivity and phenolics compounds. All that demonstrates the potential
abilities of A. iva extracts (specially methanol extract) to reduce
the postprandial increase of blood glucose levels in diabetic patient
and their capacities to prevent type 2 diabetes, and attributes the anti-
oxidant and the inhibitory activities of aerial part extracts to the poly-
phenolic and flavonoid contents of the plant. To our best knowledge,
A. iva extracts have not been yet tested for their antidiabetic
effects. Interestingly, A. iva extracts have exhibited a considerable enzy-
matic inhibition with some variability between methanol and aqueous
extract. This difference is certainly due to the functional phenolic com-
positionin each extract. Several previous works have demonstrated that
phenolic compounds may influence carbohydrate metabolism at
various levels, improving postprandial glycemic levels, fasting blood
glucose levels, acute insulin secretion, and insulin sensitivity, being
that, a strategy to help prevent DM is to limit therate of glucose absorp-
tion from the intestines into the bloodstream (Dada et al., 2017; Zaklos-
Szyda et al., 2015).
The 2000 mg/kg concentration of aqueous and methanol extracts of
A. iva do not induce any related signs of toxicity or mortality in all of the
animals of each groups, during the 14 days of study. The treatment by
each extract did not show a weight loss or changes in the behavioral
pattern or any undesired pathologic changes of the animals. Therefore,
the oral LD
50
of A.iva is greater than 2000 mg/kg (Table 4).
4. Conclusion
This preliminary study investigated the polyphenolic content, anti-
oxidant activity and digestive enzymes inhibitory activities of aqueous
and methanol extracts obtained using different extraction methods.
Our extracts exhibit a considerable antioxidant effect against the
DPPH, ABTS, and the ferric reducing power (FRAP), especially the
methanol extract. Moreover, they have an important inhibitory capacity
against the enzymes α-amylase and α-glucosidase compared to
the standard synthetic compounds. These results suggest that the
polar-extracts from this Mediterranean and underused species from
Morocco can play a therapeutic role with oxidative stress, and diabetes
mellitus type 2 by controlling the hyperglycemia. The obtained results
of this study suggest the potential application use of A. iva crude extracts
in the field of pharmaceutical industries, in particularly as anti-
hyperglycemic treatment. However, preclinical and clinical studies
along with phytochemical studies are required.
Declaration of Competing Interest
The authors have declared that there is no conflict of interest
Acknowledgement
The author Saad Fettach is extremely thankful to all co-authors for
their valuable contribution, and wishes to thank Dr. Marmouzi Ilias
and Mr. Badr Zalmat for their advices, guidance and help.
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Table 4
Effectsof Aqueous and methanolextracts of A. iva on body weight of Swiss mice with dose
of 2000 mg/kg. Data are expressed as mean ± SD (n = 6).
Extracts Dose of extract
mg/kg
Body weight (g)
Initial weight
(1st day)
Final weight
(14th day)
Difference
Aqueous
extract
2000 28 ± 1.21 31.23 ± 1.80 +3.23
Methanol
extract
2000 27 ± 1.18 29.13 ± 1.79 +2.13
Control
group
D.W 27.82 ± 4.78 30.63 ± 2.20 +2.81
Table 2
Antioxidant activities (DPPH, ABTS and FRAP) of A. iva extracts. Data are expressed as
mean ± SD (n = 3).
DPPH (IC
50
) ABTS (mg TE/g
extract)
FRAP (mg AAE/g
extract)
Aqueous extract 0.225± 0.026 49.72±0.24 78.8 ±1.18
Methanol extract 0.187± 0.016 62.19± 0.45 89.12±0.23
BHT 0.029± 0.006 ––
Ascorbic acid 0.007± 0.001 ––
mg TE/g extract: mg Trolox equivalent per gram of extract
mg AAE/g extract: mg Ascorbic Acid equivalent per gram of extract
Table 3
digestive enzymes inhibition activity (α-glucosidase and α-amylase) of A. iva extracts
expressed in IC
50
. Data are expressed as mean ± SD (n = 3).
IC
50
(mg/mL)
α-glucosidase inhibition α-amylase inhibition
Methanol extract 0.130± 0.008 0.172± 0.012
Aqueous extract 0.180± 0.005 0.210 ±0.003
Acarbose 0.018± 0.002 0.097± 0.002
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