FIELD OF THE INVENTION
This invention relates to a user friendly, safe and novel topically applied skin-lightening cosmetic composition having melanin synthesis inhibiting activity made predominantly from natural products and to methods for the manufacture of such composition.
BACKGROUND OF THE INVENTION
The skin of human beings is coloured differently in different races and also with remarkable differences even within members of the same race. The skin has been differentiated as epidermis, dermis and further deeper layers. The top most epidermis of the skin consists essentially of two major layers, the basal layer which exists at the bottom of the epidermis in contact with the dermis, and the dead corneal or honey layer above the basal layer, extending upward to tne surface of the skin.
The colour of human skin is determined by melanin, a pigment manufactured by cells known as melanocytes, residing mostly below or between the basal ceils of the epidermis. Melanin once produced, travels to the dendrites of the melanocyte.
Although primary regulation of melanin production is via genetic controls, environmental factors may also play an important role in synthesis. Exposure to sunlight or other UV radiation can stimulate the melanocytes to produce melanin.
Melanin production can also increase in response to hormone fluctuations associated with child bearing or the use of birth-control pills.
Normal pigmentation of the skin surface is uniform. However, localized, excessive pigmentation can occur and such colorization is collectively referred to as hyperpigmentation. Hyperpigmentation encompasses a wide array of afflictions all of which are accompanied by increased melanin production. Hyperpigmentation of the human skin may include skin blemishes or disorders including freckles, age spots, sunburn pigmentation and other similar small, fixed pigmented lesions. In addition and from a cosmetic standpoint, it may often be desirable to decolorize what is considered normally pigmented skin to increase "fairness" or to blend hyperpigmented regions into that of the surrounding normal skin. Regardless of the type of hyperpigmentation, it is almost always viewed as cosmetically undesirable and often to the point of being psychologically disabling to the patient.
Accordingly, a number of prior art methods and compositions have been developed in an attempt to depigment the skin. Most of these prior art attempts have focused on skin-bleaching compositions such as hydro-quinone, sodium hypochlorite, zinc peroxide, mercurous chloride, ammoniated mercury and bichloride of mercury. These compounds are often disadvantageous due to sensitization, irritation and lack of predicable results.
To be effective, any treatment must inhibit the synthesis or the activity of tyrosinase, since this enzyme is ultimately responsible for conversion of tyrosine into melanin.
It is known that certain compounds effectively inhibit synthesis of melanin. For example, recent studies have shown that 6-nitroquipazine, a serotonin uptake antagonist, inhibits melanin synthesis without affecting tyrosinase activity.
Although various depigmentation agents are known already, there is continuous search for more active materials or to improve the activity of already known materials or to increase the safety aspects of already known materials. For example, in U.S. Pat. No. 4,919,291 (Hatae) kojic acid and its esters have been combined with vitamin C in a topical composition for use as a depigmentation cream. Kojic acid is known to inhibit the synthesis of melanin. U.S. Pat. No. 3,856,934 (Kligman) discloses a topical composition combining retinoic acid and corticosteriod to synergistically create a melanin inhibiting topical composition. U.S. Pat. No. 4,096,240 (Mathur) discloses combining Niacinamide with a UV absorbing sunscreen for use in a topical composition to retard melanin dispersion or distribution into the epidermis. Although each of above noted compositions include melanin inhibiting ingredients in various topical oils, lotions or emulsions, each of the compositions has their own limitations.
The existing composition available in the market contains Niacin and/or Niacinamide as one of the Skin whitening Agents. It has been found in studies that 26% of the people using such composition were affected by irritation due to the presence of Niacin and/or Niacinamide in such composition. In the US Patent 5968528 (assigned to The P&G Company, Ohio), it has been mentioned that 'Current vitamin B3 (Niacin) formulations, however, can be drying and irritating. Such formulations may cause individuals to refrain from using vitamin B3 products as frequently and copiously as is necessary for optimum benefit. Vitamin B3 compound means (a) Niacinamide (b) Nicotinic acid (3) Nicotinyl alcohol and derivatives thereof; and slats of any of the foregoing'. Therefore, cosmetic compositions containing Niacin, Niacinamide or its derivatives are not user friendly and safe to use in the long run.
Most of the presently available skin whitening agents are synthetic chemicals or chemicals which are occurring in nature but the materials used in the compositions are synthesised in Laboratories.
It is in the continuous search for inventing/improving user friendly and safe natural herbal extracts as skin whitening agents, the present patent is related with.
It is therefore an object of the present invention to provide a user friendly and safe skin lightening cosmetic composition.
It is a further object of the present invention to provide a cosmetic composition which comprises substantially of natural products.
It is a further object of the present invention to provide a cosmetic composition which not only has virtually no side effects but also protects the skin from harmful UV radiations.
SUMMARY OF THE INVENTION
The present invention is related to a skin lightening topical cosmetic composition which comprises a synergistic combination of the undermentioned herbal extracts-
1. Doorba (Cynodon dactylon)
2. Kustha (Saussurea lappa)
3. Sariva (Haemindus indicus)
4. Gurmar (Gymnema sylvestre)
Besides, the composition may also comprise of Manjistha (Rubia cordifolia), Priyangu (Callicara macrophylla) and Usheer (Vetiveria zizaniodes).
DESCRIPTION OF THE INVENTION
The present invention relates to novel composition for skin lightening through herbal extract(s) for lightening (whitening) the skin, which promotes depigmentation of the human skin and process for the manufacture of such composition.
It has been found by the inventors during their continuous search for suitable herb(s) for the benefits of the skin to improves its complexion and condition, that some of the herb(s), reported herein, have the synergistic and surprising properties of lightening (whitening) the skin, making the skin whiter, brighter.
The composition of the present invention is unique in that it protects the skin from the harmful UV radiations and at the same time reduces the melanin synthesis by using herbal extract(s) and thereby resulting in skin lightening.
The composition of the present invention is also characterized by the feature that it has a high SPF (Sun Protection Factor) preferably in the range of 1 to 10, which can go to as high as 30.
The ingredients of the composition of the present invention being from natural sources is also unique, since it has virtually no side effects and is rather very much compatible with the skin.
The inventors of the present invention have also developed novel processes for extracting the active ingredients from the herb(s) and plant(s), in the right proportion and concentration and thereafter incorporating it in a suitable delivery form, such as a cream, lotion, gel, oil, etc. for topical application on the skin.
In accordance with the present invention, the composition of the present invention comprises a synergistic combination of the undermentioned herbal extracts-
1. Doorba (Cynodon dactylon)
2. Kustha (Saussurea lappa)
3. Sariva (Haemindus indicus)
4. Gurmar (Gymnema sylvestre)
Preferably the cosmetic composition comprises the herbal extracts in the
following range-
1. Doorba {Cynodon dactylon) from 0.1 % to 99.9 % w/w
2. Kustha (Saussurea lappa) from 0.1 % to 99.9 % % w/w
3. Sariva (Haemindus indicus) from 0.1 % to 99.9 % % w/w
4. Gurmar (Gymnema sylvestre) from 0.1% to 99.9 %% w/w
More preferably the cosmetic composition further comprises one or more of the undermentioned herbal extracts in the range mentioned-
1. Manjistha (Rubia cordifolia) 1.0 to 99.0 % w/w
2. Priyangu {Callicara macrophylla) 1.0 to 99.0 % w/w
3. Usheer (Vetiveria zizaniodes) 1.0 to 99.0 % w/w
Preferably the composition comprises one or more skin conditioning agents.
More preferably the skin conditioning agents are selected from the group comprising Masoordaal, Saffron, Sandalwood, Milk, Papaya, Liquorice, Achuka, purified water, Coconut water / coconut milk alone or combination thereof.
Preferably the composition may further comprise known skin lightening (whitening) agents.
More preferably the skin lightening agents are selected from the group comprising Arbutin, Niacinamide alone or in combination.
Preferably the composition comprises one or more sunscreen agents, comprising chemical sunscreens (UVA and UVB absorbers) like Octyl methoxycinnamate, Avobenzone, Oxybenzone, etc., alone or combination thereof or physical sunscreens (of various particle size) like Titanium dioxide, Zinc oxide etc., alone or in combination thereof.
Experiment 1:
The following extracts were prepared by extraction in various solvents like Water (Aqua), Alcohol, Aqueous-Alcoholic, Oil or any combination thereof, of the whole or part of the herb selected from the following group -
1. Doorba {Cynodon dactylon)
2. Kustha (Saussurea lappa)
3. Manjistha (Rubia cordifolia)
4. Priyangu (Callicara macrophylla)
5. Sariva (Haemindus indicus)
6. Usheer (Vetiveria zizaniodes)
7. Gurmar {Gymnema sylvestre)
Besides the above disclosed herbs the composition may also contain
8. Masoor daal
9. Saffron
10. Sandalwood
11. Milk
In accordance with the present invention, extracts of these herbs were made in various solvents (as mentioned above) by several methods and studied for their skin lightening property.
Experiment 2:
The analysis of the skin pigmentation was performed using Mexameter MX 18 (Courage and Khazaka).
This instrument Mexameter measures the melanin content (responsible for the colour of the skin) of the skin, using a probe. The instrument contains a probe, which emits light. When pressed on the skin, the melanin of the skin absorbs some of the light and the instrument measures the difference between the emitted and reflected light, using sophisticated electronic circuit. The amount of light absorbed depends on the colour of the skin, which in turn depends on its melanin content. The probe and the instrument are so sensitive that even smallest differences in the skin colour could be detected. At the same time, the probe controls the environmental light, using a foamed ring, so that there is no interference from the light emitted from other light sources.
The skin lightening efficacy of the herbal extract(s) as well as the compositions containing these extract(s) were studied using this Mexameter instrument. The Herbal extract individually as well as in mixture were applied on the skin of the hand twice a day (in the morning and in the evening) for 24 days on previously cleaned skin and left in contact with the skin for the rest of the time. As control, plain water was used.
The compositions (cream, lotion, gel, oil, etc) made with the herbal extract(s) were also studied twice a day (in the morning and in the evening) for 24 days on previously cleaned hands and left in contact with the skin for the rest of the time and the measurements were made at regular intervals. As control, the base product (cream, lotion, gel, oil, etc) was used.
In addition to the Mexameter readings the change in the colour of the skin was recorded by a panel of experienced individuals/ volunteers. Their observations also showed that the herbal(s) extracts have skin whitening property and synergism between the herbs in whitening the skin. Also the improvement in the efficacy of the other known skin whitening agents with the herbal extract(s) observed.
For example, a 5 % extract of Doorba decreased the melanin content of the skin by 19 % in 24 days, a 10 % extract of Kustha by 13 % in 24 days and a 10 % Extract of Gurmar by 45 % in 24 days and a 5% extract of Sariva decreased the melanin content by 12%. On the other hand a mixture of 5% of an extract of all these four herbs decreased the melanin content of the skin by 52% in 24 days. This is a surprising and synergistic activity not expected of the herbs individually.
It is also observed that the herbal extract(s) individually or as a mixture thereof does not produce any adverse reaction on the skin, like skin redness, rash
formation, etc or any other allergic reaction on the individuals/volunteers. This shows that they are safe to use on the skin.
As an example, the skin lightening effect of the pure herbal extract; on the skin is presented in the following Graph 1:
(Graph Removed)
Graph 1 As clear from the Graph 1, the percentage change in the melanin content of the skin decreases on application of the Herbal extract when compared to the control (Water).
A cream composition was made with the herbal extract. The percentage of the herbal extract may change from 0.1 to 90 % preferably from 20 to 70 % and more preferably from 5 to 40 %. In addition to the herbal extract, a known skin lightening agent, viz. Arbutin was used in the composition. As control, a cream composition containing Arbutin only was used. The composition may also
contain sunscreen agents. The observations were presented in the following Graph 2.
(Graph Removed)
As clear from the Graph 2, the composition containing the herbal extract in
addition to the Arbutin lightens the skin better than the cream containing Arbutin
only.
Further, another cosmetic composition containing another known skin lightening
agent, Niacinamide was evaluated with and without the herbal extract. The
findings were presented in the following Graph 3:
(Graph Removed)
Graph 3 CONCULSIONS As clear from the above studies and the Graph 1, the extracts were found to lighten the skin colour. Further, as evident from the Graphs 2 and 3, the Herbal Extracts improve the efficacy of the already known skin lightening (whitening) agents like Arbutin, Niacin and its derivatives, and other skin whitening agents, in a synergistic manner.
The composition may also contain chemical sunscreens (UVA and UVA absorbers) like Octyl methoxycinnamate, Avobenzone, Oxybenzone, etc., alone or combination thereof or physical sunscreens (of various particle size) like Titanium dioxide, Zinc oxide etc., alone or combination thereof to improve the efficacy of the composition.
The invention will now be described with reference to the following examples which are only illustrative and should in no way be understood to limit the scope of the invention in any manner whatsoever:
Example 1 -
A cream was prepared by using the ingredients of the Herbal extract as
mentioned hereinbelow and as discussed hereinbefore -
Item Weight
1. Dorba 5-10 gm
2. Kustha 5-10 gm
3. Sariva 5-10 gm
4. Gurmar 2-5 gm
Example 2-
A cream was prepared by using the ingredients of the Herbal extract as
mentioned hereinbelow and as discussed hereinbefore -
Item Weight
1. Dorba 5-10 gm
2. Kustha 5-10 gm
3. Sariva 5-10 gm
4. Gurmar 2-5 gm 5.Manjistha 15-25 gm

6. Priyangu
7. Usheer 15-25 gm
Example 3-
A cream was prepared by using the ingredients of the Herbal extract as
mentioned hereinbelow and as discussed hereinbefore -
Item Weight
LDorba 5-10 gm
2. Kustha 5-10 gm
3. Sariva 5-10 gm
4. Gurmar 2-5 gm 5.Manjistha 15-25 gm

6. Priyangu
7. Usheer 15-25 gm
8. Milk 1-3 gm
9. Arbutin 0.1-5gm
10. Octyl methoxycinnamate 0.5 -8gm

WE CLAIM
1. A skin lightening topical cosmetic composition which comprises a synergistic
combination of the undermentioned herbal extracts-
1. Doorba (Cynodon dactylon)
2. Kustha (Saussurea lappa)
3. Sariva (Haemindus indicus)
4. Gurmar (Gymnema sylvestre)
2. A cosmetic composition as claimed in claim 1 which comprises the herbal extracts in the following range-
1. Doorba (Cynodon dactylon) from 0.1 % to 99.9 % w/w
2. Kustha {Saussurea lappa) from 0.1% to 99.9 %% w/w
3. Sariva (Haemindus indicus) from 0.1 % to 99.9 % % w/w
4. Gurmar (Gymnema sylvestre) from 0.1 % to 99.9 % % w/w
3. A skin lightening cosmetic composition as claimed in claim 1 which further comprises one or more of the undermentioned herbal extracts in the range mentioned-
1. Manjistha (Rubia cordifolia) 1.0 to 99.0 % w/w
2. Priyangu (Callicara macrophylla) 1.0 to 99.0 % w/w
3. Usheer (Vetiveria zizaniodes) 1.0 to 99.0 % w/w

4. A composition as claimed in claim 1 or 2 which further comprises one or more skin conditioning agents.
5. A composition as claimed in claim 3 wherein the skin conditioning agents are selected from the group comprising Masoor daal, Saffron, Sandalwood and Milk,
Papaya, Liquorice, Manjistha, Sariva, Achuka, purified water, Coconut water / coconut milk alone or combination thereof.
6. A composition as claimed in claim 1 or 2 which further comprises one or more skin lightening (whitening) agents.
7. A composition as claimed in claim 5 wherein the skin lightening agents are selected from the group comprising Arbutin, Niacinamide, or any other Skin Lightening agents known in the art or to be developed, alone or in combination
8. A composition as claimed in claim 1 or 2 which further comprises one or more sunscreen agents.
9. A composition as claimed in 7 wherein the sunscreen agents are selected from the group comprising Octyl methoxycinnamate, Avobenzone, Oxybenzone, etc, physical sunscreens (of various particle size) such as like Titanium dioxide, Zinc oxide, etc alone or in combination thereof.
10. A composition as claimed in any of the preceding claims which is in a
topically usable form such as a cream, lotion, gel, oil, emulsion and the like.
11. A process for the manufacture of a skin lightening topical composition which
comprises mixing together in any conventional manner a synergistic combination
of herbal extracts of the following herbs
1. Doorba (Cynodon dactylon)
2. Kustha (Saussurea lappa)
3. Sariva (Haemindus indicus)
4. Gurmar {Gymnema sylvestre)
and preparation of a suitable dosage form to be used topically.
12. A skin whitening topical cosmetic composition substantially as herein described with reference to the foregoing description and the accompanying experiments and examples.
13. A process for the preparation of a skin whitening topical cosmetic composition substantially as herein described with reference to the foregoing description and the accompanying experiments and examples.