*Corresponding author,
e-mail : anis.yohana.chaerunisaa@unpad.ac.id (A. Y.
Chaerunisaa)
https://doi.org/10.24198/idjp.v2i1.26106
© 2020 Rahmania et al
Vol 2, Issue 1, 2020 (20-26)
http://journal.unpad.ac.id/idjp
Formulation of Antioxidant Emulgel containing Beluntas China (Gynura
pseudochina (L.) DC)
Fitriani J. Rahmania1, Marline A. Bratadiredja1, Muhaimin2, Anis Y. Chaerunisaa
1*
1 Department of Pharmaceutical Technology, Faculty of Pharmacy, Universitas Padjadjaran, West Java –
Indonesia
2 Department of Chemistry, Faculty of Science and Technology, Universitas Jambi, Jambi – Indonesia
Received: 5 Feb 2020/Revised: 8 Feb 2020/Accepted: 12 Feb 2020/Published: 12 Feb 2020
ABSTRACT
Skin exposed by the environmental stresses constantly, such as pollutants, solar radiation, heat, and

be reduced by natural antioxidants such as Beluntas china (Gynura pseudochina (L.) DC) extract. The
antioxidants use of beluntas china extract for skin will be more optimal if it is applied by appropriate
form, emulgel, which has stronger consistency and longer contact time than gel due its lipophilic content.
The aim of this research was to formulate an antioxidant emulgel from beluntas china extract, which

gelling agents which were carrageenan, hydroxypropyl methylcellulose (HPMC), and carbomer 934.
Then, the physical stability was evaluated, including organoleptic, homogeneity, pH, viscosity, and
freeze thaw. The results showed that formulation of carbomer 934 1% 2xIC
50
extract concentration give
the best physical stability evaluationat at room temperature for 60 days storage time.
Keywords: antioxidant, beluntas china extract, emulgel, free radicals, skin
1. Introduction
Skin is one of the body’s largest organs and
protects the body from various types of stimuli,
external damage and loss of moisture. However, the
skin is constantly exposed by daily environmental
stresses such as pollutants, solar radiation, heat, and
cold, which form reactive oxygen species (ROS)
from oxygen-based molecules that contain unpaired
electrons (free radicals) such as super oxide (O
2-
) or hydrogen peroxide (H
2
O) [1]. Free radicals
cause damage to DNA, collagen, elastin, and
hydration balance which is important for elasticity
and skin renewal process, so that cause aging and

Antioxidants are compounds that inhibit oxidation
reactions with free formation chain reactions, thus
prevent the formation of peroxides, and even cell
damage will be inhibited [7, 8]. There are 2 types
of antioxidants, which are natural and synthetic.
However, the use of synthetic antioxidants could be
carcinogenic and toxic if it is used for a long time
and high doses [9]. Therefore, natural sources of
antioxidants are needed, one of it is Beluntas China
(Gynura pseudochina (L.) DC).
Beluntas China is one of Indonesian native plant
that has been used by the ancient as traditional
medicine [10-12]. Based on several research, it is

analgesic, and decreasing cholesterol levels [13].
Beluntas China contains chemicals that are useful

saponins, tannins, terpenoids, and sterols. Phenolics

of Beluntas China leaves [14, 15].
Emulgel is a gel consist of lipid phases dispersed
in water and a two-phase system that contains
water and lipid molecules. Emulgel has a better
consistency, lower risk of forming coalescence
and more stable viscosity, so it can reduce the
foam structure of the emulgel itself. Emulgel has
the advantage of being a hydrophobic material
carrier that cannot be integrated directly into a gel
base [16]. Based on this background, research on
the formulation of emulgel antioxidants containing
Beluntas China extract has been carried out.
Emulgels were formulated using various gelling
agents to optimize its physicochemical stability
during storage.
F. J. Rahmania et al / Indo J Pharm 1 (2020) 20-26
21
2. Methods
2.1 Extraction
Gynura pseudochina (L.) DC was obtained from
the Jambi area, Jambi Province. Beluntas china was
cleaned, air-dried for 7 days, chopped until they are
somewhat powdery and weighed 1 kg. Simplisia
of beluntas china macerated with 70% ethanol
solvent for 3x24 hours at room temperature. Then


with a rotary evaporator so that a thick extract was
obtained [17]. To obtain the extract yield value, the
extract is calculated by the following equation:
........... (Eq. 1)
2.2 Phytochemical Screening
Phytochemical screening was carried out on
both simplisia and extract of beluntas china leaf
to determine the content of secondary metabolites

polyphenols, saponins, steroids and triterpenoids,
quinones, monoterpenoids, and sesquiterpenoids.
2.3 Formulation of Emulgel Antioxidant Beluntas
China Extract
Emulgel base optimization was conducted
by determining the two best concentrations
between three types of gelling agent, which were
carrageenan, HPMC, and carbomer. Emulgel base
optimization was shown in Table 1.
Table 1. Emulgel Base Optimization
Ingredients
F1
(%)
F2
(%)
F3
(%)
F4
(%)
F5
(%)
F6
(%)
Carrageenan 1 1.25 - - - -
HPMC - - 5 6 - -
Carbomer - - - - 0.5 1
 7.5 7.5 7.5 7.5 7.5 7.5
Tween 20 1 1 3 3 1 1
Span 20 1.5 1.5 4.5 4.5 1.5 1.5
Propylene
glycol
10 10 10 10 10 10
Nipagin 0.03 0.03 0.03 0.03 0.03 0.03
Nipasol 0.01 0.01 0.01 0.01 0.01 0.01
TEA - - - - 1 1
Aquadest
Ad
100
Ad
100
Ad
100
Ad
100
Ad
100
Ad
100
F1 = Carrageenan 1%; F2 = Carrageenan 1,25%; F3 = HPMC
5%; F4 = HPMC 6%; F5 = Carbomer 0,5%; F6 = Carbomer
1%
Antioxidant emulgel formula containing beluntas
china extract is listed in Table 2. The concentration
of beluntas china was determined based on the
antioxidant activity test using the DPPH method
which is 2 x IC
50
. Emulsions were made by heating
  
water phase (Propyleneglycol, tween 20, nipagin,
and nipasol in aquadest) on a water bath at 60-
70°C. Both phases were mixed, then added by
extract of Gynura pseudochina, methylparaben,
and propylparaben (preservative) that had been
dissolved in propylene glycol (humectant). It was
stirred until homogenous. Furthermore, gelling
agents (carrageenan, HPMC, and carbomer) in
which concentration based on optimization results
were then added to the emulsion and stirred
homogeneously.
Table 2. Formulation of Emulgel Antioxidant Beluntas
China Extract
Ingredients
F1a
(%)
F1b
(%)
F4a
(%)
F4b
(%)
F6a
(%)
F6b
(%)
Beluntas
China Extract
-
2 x
IC
50
-
2 x
IC
50
-
2 x
IC
50
Carrageenan 1 1 - - - -
HPMC - - 6 6 - -
Carbomer - - - - 1 1
Liquid

7.5 7.5 7.5 7.5 7.5 7.5
Tween 20 1 1 3 3 1 1
Span 20 1.5 1.5 4.5 4.5 3 3
Propylene
glycol
10 10 10 10 10 10
Nipagin 0.03 0.03 0.03 0.03 0.03 0.03
Nipasol 0.01 0.01 0.01 0.01 0.01 0.01
TEA - - - - 1 1
Aquadest
Ad
100
Ad
100
Ad
100
Ad
100
Ad
100
Ad
100
F1a = Carrageenan w/o extract; F1b = Carrageenan 2x IC50
extract; F4a = HPMC w/o extract; F4b = HPMC 2x IC50
extract; F6a = Carbomer w/o extract; F6b = Carbomer 2x
IC50 extract
2.4 Physical Stability Evaluation of Emulgel
Antioxidant Beluntas China Extract
Physical evaluations involved organoleptic,
homogeneity, pH, viscosity, and freeze – thaw
F. J. Rahmania et al / Indo J Pharm 1 (2020) 20-26
22
were done at day- 0, 3, 7, 14, 28, 42, and 60. The
organoleptic and homogeneity evaluations were
carried out by visually observing the changes in
shape, color, and odor of the emulgel [18]. The
pH measurement was done using a pH meter by
dissolving a sample of 1 g into 10 mL of distilled
        
pH change during storage time [19]. Viscosity was

appropriate spindle and speed (rpm) [20]. Freeze
thaw was done by storing the sample at 4ºC for
48 hours then transferred to 40ºC for 48 hours (1
cycle). It was done for 5 cycle. Every one cycle
was complete, then checked if there was a phase
separation occurs [18].
3. Result
3.1 Extraction
200 grams of simplicia were extracted using

compounds is higher in extracts with hydro-catholic
solvents compared with extracts that use ethanol
or pure methanol [21]. The extraction process was
done by maceration. The thick extract was obtained
for 14.84 grams with a yield of 7.42%. Organoleptic
examination of beluntas china ethanol extract
showed that the extract was in the form of thick
liquid, distinctively smelling, dark green and bitter.
3.2 Phytochemical Screening
Phytochemical screening was carried out to
determine the content of secondary metabolites
contained in the extract qualitatively. Based on
the results of phytochemical screening-detected
in simplicia and ethanol extracts of beluntas china
    
saponins, and steroids. Flavonoid and polyphenols
detected by phytochemical screening are the active
compounds used as antioxidants [22-24].
3.3 Formulation of Emulgel Antioxidant Beluntas
China Extract
The formula with the most stable evaluation
results of each type of gelling agent for 7 days will
be used as a base for variations of the formulation
added by the extract later. The parameters
observed were Organoleptic and Homogeneity,
pH (Figure 1), and Viscosity (Figure 2). Based on
observations, all emulgel bases are white, odorless,
and homogeneous. The selected base concentration
from each type of gelling agent are F1 (carrageenan
1%), F4 (HPMC 6%), and F6 (carbomer 1%).
Figure 1. pH During the Optimization Period
Figure 2. Viscosity During the Optimization Period
(F1 = Carrageenan 1%; F2 = Carrageenan
1,25%; F3 = HPMC 5%; F4 = HPMC 6%; F5
= Carbomer 0,5%; F6 = Carbomer 1%)
3.4 Physical Stability Evaluation of Emulgel
Antioxidant Beluntas China Extract
The result of organoleptic and homogeneity
evaluations is shown in Table 3, while pH in Figure
3, and Viscosity in Figure 4. The results of the
freeze-thaw test showed that F1a, F1b, F6a, and
F6b showed physical stability for 5 cycles, but F4a
and F4b showed phase separation in the 3
rd
cycle.
This indicated that the formula was not resistant to
temperature stress.
F. J. Rahmania et al / Indo J Pharm 1 (2020) 20-26
23
Table 3. Organoleptic and Homogeneity of Emulgel
Antioxidant Beluntas China Extract
Charac-
teristic
Day
F1a
(%)
F1b
(%)
F4a
(%)
F4b
(%)
F6a
(%)
F6b
(%)
Color
1 W G W G W G
3 W G W G W G
7 W G W G W G
14 W G W G W G
28 W G W G W G
42 W G W G W G
60 W G W G W G
Odor
1 OL OL OL OL OL OL
3 OL OL OL OL OL OL
7 OL OL OL OL OL OL
14 OL OL OL OL OL OL
28 OL OL OL OL OL OL
42 OL OL OL OL OL OL
60 OL OL OL OL OL OL
Homoge-
neity
1 H H H H H H
3 H H H H H H
7 H H H H H H
14 H H H H H H
28 H H H H H H
42 H H H H H H
60 H H H H H H
Color – W (White); G (Green); Odor – OL (Odorless); SO
       
homogeneous)
Figure 3. pH of Emulgel after 60 Days (n=3)
4. Discussion
4.1 Formulation of Emulgel Antioxidant Beluntas
China Extract
Carrageenan is one of the carbohydrate
polymers derived from seaweed, especially
Eucheuma cottonii. Carrageenan can form a gel in a
thermoreversible manner so that it is widely used as
a gelling agent, thickener, and stabilizer in various
industries such as food, medicine, cosmetics, and
textiles [25]. HPMC produces clear, odorless, and
tasteless products. It is commonly used in topical
preparations and it resistants to phenol compounds
so that beluntas china ethanol extracts will not
be damaged [26, 27]. Carbomer 934 has better
properties for the release of active substances
and easy dispersion [28, 29]. Carbomer is a very
acidic compound (pH 2-3), so that triethanolamine
(TEA) is needed to balance the pH in the emulgel
which was an ionized form. When it is added, the
carbomers pH increases to pH 6-7. Under these
conditions, the carbomer becomes thicker, because
the carboxyl group of the carbomer will change to
(COO
-
) so that the carbomer expands and becomes
more rigid [30].
      
spread of dispersion, increase in adhesion, and
inhibit the release of active substances [25]. Based
on the viscosity graphic images during optimization,
the viscosity will increase along with the high
concentration of the gelling agent in the emulgel.
       
is caused by the structure of each gel base, the
more hydroxyl groups (-OH) on the gel base, the
higher the viscosity. This hydroxyl group will form
hydrogen bonds with water molecules that play a
role in the hydration process during the swelling
process [26].
The pH stability is also one of the factors in
determining the best formula because the pH of
the preparation is expected to remain stable during
storage so that it stays within the skin’s pH range of
4.5 - 6.5 [27].
Figure 4. Viscosity of Emulgel after 60 Days (n=3)
F. J. Rahmania et al / Indo J Pharm 1 (2020) 20-26
24
Formula 1 (carrageenan 1%), Formula 4
(HPMC 6%), and Formula 6 (carbomer 1%) were
chosen because they provide better stability, pH,
viscosity and organoleptic compared to formula 2
(carrageenan 1.25%), formula 3 (HPMC 5%), and
formula 5 (carbomer 0.5%). This can be seen from
the standard deviation values of pH and viscosity
for 7 days of stable observation.
4.2 Physical Stability Evaluation of Emulgel
Antioxidant Beluntas China Extract
Organoleptic and homogeneity test was done
by visually observation involved odor, color,
      
organoleptic in terms of color. It turned green
after the extract was added, while observations of
odor, consistency, and homogeneity did not show

To see stability during the observation period, the
pH value of the preparation needs to be considered.
Based on Figure 3, it can be seen that the longer the
storage time, the relative pH decreases. However,
the pH reduction of the preparation is still in the
skin pH range of 4.6 - 6.5 so that changes in pH are
still acceptable. The pH value used in this topical
preparation must be by the skin’s pH range of
4.5 - 6.5. In this range, the skin can accept topical
preparations that do not irritate. If the preparation
is below pH 4.5 will cause skin irritation while the
preparation is above pH 6.5 will cause scaly skin
[27].
A decrease in pH value during storage can
       which reacts with
the aqueous phase on the preparation so that it
becomes acidic [20]. The concentration of H
+
ions
is used as a measure of the acidity of a solution,
if the solvent contains CO, the CO will bind to
the H
+
ion and then reduce the concentration of
H
+
ions in the solution so that the pH becomes
higher than the original. The pH will become more
alkaline if the amount of H
+
ions in the preparation

by temperature, the content of other substances in
the preparations that react, which can disturb the
stability of the pH [26].
Viscosity is used as an evaluation parameter
     
the dispersion, adhesion, and release of active
substances. The speed of drug release will increase
with decreasing viscosity. This is because the higher
the viscosity will form a strong barrier so that the
rate of drug release slows [25, 29]. Viscosity of
topical formulation should be physically give good
rheology for ease in handling and distributio, as well


for topical preparation has been stated.
The optimum viscosity will maintain the active
substance to be dispersed and maintain uniformity
of concentration on that basis [30]. The longer the


The decrease in viscosity can also occur due to the
impermeable preparation of the container so that the
preparation can absorb water from the environment
so that the volume of water in the preparation
increases and decreases the viscosity [20]. The
resulting viscosity value based on Figure 4 of each
formula is lower when compared to each negative
control, namely due to the extract given into the
preparation thereby reducing the consistency of the
preparation [16].
5. Conclusion
Based on research on the formulation of
antioxidant emulgel beluntas china extract (Gynura
pseudochina (L.) DC), it can be concluded that
the best emulgel base formulation of each type of
gelling agent based on the evaluation of physical
observations shown by 1% carrageenan, 6%
HPMC, and carbomer 934 1% base. And, the best
formula of antioxidant emulgel beluntas china
(Gynura pseudochina (L.) DC) extract based on
physical evaluation during storage is carbomer 934
1%.
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