Field of the invention
The present invention relates to herbal formulation derived from Cassia auriculata
flowers useful for protection of skin from ageing and to control the multiplication of
microbes. More particularly the formulation of the present invention comprising extract
from the said herb provide superior skin benefits in terms of skin whitening (tyrosinase
inhibition), anti-aging (anti-oxidant property) and pathogen protection (anti-microbial).
Background and prior art
A large number of skin care formulations are available for addressing the skin benefits
like whitening, anti-wrinkle, anti-aging, skin tightening and UV protection. These
formulations when topically applied on the skin may or may not interfere in the melanin
synthesis, a key characteristic of skin lightening and inhibiting the growth of
dermatophytes with or without killing them. The key actives added in these formulations
may be of natural origin or synthetic compounds, therefore posing minor or significant
side effects. Cassia auriculata is grown in different parts of India and is known for its
effects on diabetes and on leprosy and skin diseases.
JP8113515 teaches barks and leaves of Cassia auriculata showed skin beautifying
activity, hyaluronidase activity-inhibition action, antioxidant action, anti-plasmin action
and collagenase activity- inhibition action etc. However no skin-beneficial property by
the Cassia auriculata flowers is either described in this patent or known in the literature.
It has been reported in the literature that the pod husk of Cassia auriculata contains
nonacosane and nonacosan-6-one, chrysophanol, emodin and rubiadin (Khare.C.P.,
2007. Indian Medicinal plants: An illustrated dictionary. Springer publications: 127-128).
Which of this component causing the inhibiting the tyrosinase enzyme is yet to be
established. Similarly, the actives in the leaves and bark of Cassia auriculata are also
yet to be determined. No mention of this is made in the reported prior art. Cassia
auriculata extract is significantly different in chemical properties from the reported
commercial product described under Cassia betaglycan species.
Objects of the invention
The primary objective of the invention is to provide a composition comprising extract of
Cassia auriculata in amount of 0.5 - 5% for the skin whitening activity.
This invention is also to provide a composition comprising extract Cassia auriculata in
amount of 0.5 - 5.0% for the anti-oxidant activity in Cassia auriculata flower, which
signifies the anti-aging property.
Another objective of this invention is to provide a composition comprising extract of
Cassia auriculata in amount of 0.5 - 5.0% for the anti-microbial properties, which has
bearing on its germ protection of human skin
Detailed Description of the Invention
The properties of Cassia auriculata as anti-diabetic remedy known in the traditional
medical literature and its practice by humans put this herb in the list of potential safe
ingredients, which can be readily used in product formulations for topical application on
human skin.
Cassia auriculata has been shown to provide superior skin benefits in terms of skin
whitening (tyrosinase inhibition), anti-aging (anti-oxidant property) and pathogen
protection (anti-microbial). The extract has no or low side effects when compared with
other chemical ingredients, as they are known and used as hypo-glycemic compounds
as reported in traditional medical practices
A group of enzymes namely, tyrosinase and tyrosinase related proteins are responsible
for skin darkening as they are involved in melanogenesis. Inhibition of these enzymes
prevents the melanin accumulation, responsible for the skin darkness. The normal
microbial flora of the skin is responsible for various manifestations ranging from malodor
to superficial infections like acne when the number of microbes increases. The
multiplication of microbial flora can be prevented or controlled by using various
antimicrobials. A number of chemical ingredients have inhibitory property against the
action of tyrosinase and controlling the number of microbes.
The present invention is directed towards formulation comprising herbal extracts of
Cassia auriculata flowers to inhibit the tyrosinase enzyme, to protect the skin from aging
through the anti-oxidant property and to control the multiplication of microbes.
The composition comprises extract of Cassia auriculata flowers in water or petroleum
ether
The chemical components present in the aqueous extract were found to be responsible
for the tyrosinase inhibition properties, whereas petroleum ether extracts were found to
be effective as anti-oxidant and antimicrobial agents.
The composition of the present invention comprises extracts of Cassia auriculata
flowers in amount of 0.5 to10.0 %, preferably 0.5 to 5%, most preferably 1 to 3%.
Other components that may be included in the composition include sunscreen, Octyl
methyl cinnamate.
The carrier include polyoxyethylene (2) strearyl ether, polyethylene (21) stearyl ether
and isopropyl palmitate.
Further conventional additives include, staeric acid, cetostearyl alcohol, mineral oil and
propylene glycol.
The process of preparing the composition comprises the steps of hot mixing and
emulsification followed by cooling.
The invention is now defined by way of non limiting illustrative examples:
Example 1.
A composition comprising Cassia extracts as in the present invention was prepared by
extracting dry flowers in water (1:10 ratio) and continuously extracting for 1hr at 50 deg
C. The mixture was cooled to room temperature, filtered and centrifuged the filtrate to
obtain a clear yellow liquid and compared with known compositions.
The skin beneficial properties exhibited by Cassia extracts, like skin lightening, anti-
aging and protection against skin pathogens were evaluated by several standard in-vitro
biochemical and microbiological assays.
A number of herbal extracts in the current studies showed significant activities beneficial
to the skin. Herbal extracts derived from Cassia auriculata flower showed skin lightening
properties superior to the well-known Glycyrrhiza glabra (licorice) extract. Skin
darkening / toning is due to the production of a group of pigments called Melanin. The
biochemical pathway involved in the production of melanin is a multi-step process,
catalysed by various enzymes. Tyrosinase is the key regulatory enzyme involved in
initiating the pigment production. If an inhibitor either from natural or syntheic source
blocks the activity of this enzyme, it will result in the skin lightening benefits. In order to
screen the herbals for its skin lightening property, tyrosinase enzyme isolated from the
mushroom was used as a model system in the cosmetic industry over decades. From
the in-vitro experiments, it is ascertained that the extract of Cassia auriculata flowers
contains compounds capable of blocking/suppressing one or more steps in the
biochemical pathways of melanin synthesis. During the current work, we evaluated the
efficacy of the plant extract in inhibiting the activity of enzyme and it was expressed in
terms of percentage inhibition (in comparison with the corresponding control). The
percentage inhibition of tyrosinase by Cassia auriculata was much higher than that
exhibited by licorice extracts of similar concentrations; the latter extract is commonly
used in commercial formulations of skin lightening creams. These superior multi-
beneficial properties of Cassia auriculata open up potential opportunities for its usage
in skin creams as skin whitening, anti-aging and anti- microbial actives.
Mushroom tyrosinase inhibition assay was carried out by incubating the enzyme with
buffered substrate with and without inhibitors for 30 mins. The absorbance was read at
492 nm and the percentage inhibition of the extracts on the enzyme was calculated
(Kang Tae Lee, Kwang Sik Lee, Ji Hean Jeong, Byoung Kee Jo, Moon Young Heo, and
Hyun Pyo Kim, 2003. Inhibitory effects of lamulus mori extracts on melanogenesis. J.
Cosmet. sci., 54, 133-142). The results were compared with various herbal extracts and
also the Glycyrrhiza glabra extract, which is normally used in commercial skin whitening
creams, acting through its tyrosinase inhibition property. The percent inhibition of
Cassia auriculata was found to be superior to Glycyrrhiza extract.
The percent inhibition of tyrosinase activity by various herbal extracts is given in Table
1. It is quite evident from these data that Cassia auriculata flower aqueous extract is
superior in its tyrosinase inhibition activity and better than a commercially used skin
whitening licorice extract.
Table 1. Percent inhibition of tyrosinase by herbal extracts

Note: Aq -Aqueous extract, PET- Petroleum Ether extract,
Example 2
In the process of aging, there is an imbalance between the reactive oxygen/ nitrogen
species and its counteracting antioxidant systems in the cell. Such imbalance results in
the free radical mediated damage of the cellular macromolecules. Membrane lipids are
the major site of attack for the free radicals because cell membrane comprises of the
unsaturated fatty acids like linoleic acid, linolenic acid and Arachidonic acid. Since
unsaturated fatty acids easily prone to free radical mediated damage and results in the
formation of lipid peroxides. Thus free radical mediated damage to lipids results in the
altered fluidity of cell, which reflects in the texture of skin.
One-way of protecting the skin texture due to aging is to prevent the lipid peroxidation.
Such prevention can happen in the aging skin though the supplement of antioxidants to
the skin cell through topical applications. Since medicinal plants are the very good
source of antioxidants, they are evaluated for their antioxidant potential by using linoleic
acid micelles as a model of membrane.
In the standard protocol used, a predetermined amount of linoleic acid was oxidized by
air at 40 °C by overnight incubation (Kikuzaki H, Nakatani N. 1993. Antioxidant effects
of some ginger constituents. J Food Sci 58: 1407-1410). The extent of inhibiting the
oxidation lipids by the herbal compounds was determined as percent inhibition. The
percent inhibition of lipid peroxidation activity by various herbals is given in Table 2. It is
quite evident that the petroleum ether extract of Cassia auriculata is again superior in
LPO inhibition than any other herbal extract studied in this project.
Table 2: Percent inhibition of LPO by herbal extracts

Note: Aq -Aqueous extract, PE- Petroleum Ether extract,
Ac- Acetone extract, Me- Methanol extract
Example 3
The skin, our body's largest organ, is located at the interface between the external and
internal environments, and so is strategically placed to harbor many microorganisms
from the environment. The population (Count) and the various types of the
microorganisms that harbours in the skin decides the harmness and pathogenecity. In
order to protect the skin from infections and biological insults, it is essential to control
the growth of microbes on the skin. Medicinal plants acts as good source of
antimicrobial agent against a wide spectrum of microorganisms. Hence the antimicrobial
efficacy of the extracts was determined by disc diffusion method (Bauer, A. W., W. M.
Kirby, J. C. Sherris, and M.Turck. 1966. Antibiotic susceptibility testing by a
standardizedsingle disc method. Am. J. Clin. Pathol. 45: 493-496) against Escherichia
co/i and Staphylococus aureus. The inoculated plates containing the herbal extract
coated discs were incubated for 24 hrs and the zone of inhibition was measured (zone
of inhibition is the area wherein the extracts inhibits the growth of microorganisms). The
zone of inhibition in terms of the millimeter (mm) helps in the qualitative screening the
potential plant extracts.
Brief Description of Figures
FIG.1 Percent inhibition of tyrosinase enzyme by herbal extracts
FIG.2 Percent inhibition of LPO by herbal extracts
FIG.3 Antimicrobial activity of Cassia auriculata flower extract - Zone of Inhibition
against Escherichia coli and Staphylococcus aureus
Detailed Description of the figures
FIGURE 1 The percent inhibition of tyrosinase activity by various herbal extracts is
given in Figure 1. It is evident from these data that Cassia auriculata flower aqueous
extract is superior in its tyrosinase inhibition activity and better than a commercially
used skin whitening licorice extract.
FIGURE 2 The percent inhibition of lipid peroxidation activity by various herbals is given
in Fig.2. It is quite evident that the petroleum ether extract of Cassia auriculata is again
superior in LPO inhibition than any other herbal extract studied in this project.
FIGURE 3. Of the various herbal extracts studied for their anti-microbial properties
against Staphylococus aureus and Escherichia coli, many herbal extracts observed in
the present study showed significant activity against these species. In particular Cassia
auriculata flower extract showed a zone of inhibition of 15mm against Staphylococus
aureus.
Brief Description of Figures
FIG.1 Percent inhibition of tyrosinase enzyme by herbal extracts
FIG.2 Percent inhibition of LPO by herbal extracts
FIG.3 Antimicrobial activity of Cassia auriculata flower extract - Zone of Inhibition
against Escherichia coli and Staphylococcus aureus
Detailed Description of the figures
FIGURE 1 The percent inhibition of tyrosinase activity by various herbal extracts is
given in Figure 1. It is evident from these data that Cassia auriculata flower aqueous
extract is superior in its tyrosinase inhibition activity and better than a commercially
used skin whitening licorice extract.
FIGURE 2 The percent inhibition of lipid peroxidation activity by various herbals is given
in Fig.2. It is quite evident that the petroleum ether extract of Cassia auriculata is again
superior in LPO inhibition than any other herbal extract studied in this project.
FIGURE 3. Of the various herbal extracts studied for their anti-microbial properties
against Staphylococus aureus and Escherichia coli, many herbal extracts observed in
the present study showed significant activity against these species. In particular Cassia
auriculata flower extract showed a zone of inhibition of 15mm against Staphylococus
aureus.
We Claim
1. A herbal composition comprising extract from Cassia auriculata flowers in
aqueous or petroleum ether.
2. The composition as claimed in claim 1 wherein the extract is present in amount
0.5 to 10.0%, preferably 0.5 to 5.0%.
3. The composition as claimed in any preceding claim which comprises
conventional additives selected from polyoxyethylene(2) strearyl ether,
polyethylene(21) stearyl ether and isopropyl palmitate, staeric acid, cetostearyl
alcohol, mineral oil and propylene glycol.
4. The composition as claimed in any preceding claim wherein the Cassia
auriculata flower extract is adapted to show a zone of inhibition of 15mm against
Staphylococus aureus.
5. The composition as claimed in claim 1 comprising aqueous extract of Cassia
auriculata adapted to provide tyrosinase inhibition
6. The composition as claimed in claim 1 comprising petroleum ether extract of
Cassia auriculata adapted to provide anti-oxidant and antimicrobial effects
7. A process for preparation of a herbal composition comprising extract from
Cassia auriculata flowers comprising steps of hot mixing, emulsification
followed by cooling.

The invention provides a herbal formulation related to skin care products useful for addressing the skin beneficial properties exhibited by Cassia extracts, like skin lightening, anti-aging and protection against skin pathogens which are evaluated by several standard in-vitro biochemical and microbiological assays. It is ascertained that the extract of Cassia auriculata flowers contains compounds capable of blocking/suppressing one or more steps in the biochemical pathways of melanin synthesis. In the present work, it was observed that the percentage inhibition of tyrosinase by Cassia auriculata was much higher than that exhibited by licorice extracts. The present invention is directed towards the application of various herbal extracts, particularly of Cassia auriculata flowers to inhibit the tyrosinase enzyme, to protect the skin from aging through the anti-oxidant (studied by linoleic acid as a model system) property and to control the multiplication of microbes (determined by disc diffusion method against Escherichia coli and Staphylococus aureus).