FIELD OF THE INVENTION
The present invention relates to oral care compositions, and more particularly, to
the stabilization of herbal oral care compositions.
BACKGROUND OF THE INVENTION
Nature has endowed us with a variety of herbs that possess numerous medicinal
properties, and that are used to prepare herbal medicines. Several herbal extracts
contain powerful ingredients, which are bio-active chemical entities occurring in
nature that can be harnessed to remedy the myriad pathologies of the oral cavity.
Herbs with proven beneficial effects on the oral cavity include Anacyclus
pyrethrum, commonly referred to as Akarkara; Olea europaea, commonly
referred to as Olive tree; Acacia nilotica, commonly known by the name of Babul
or Kikar; Azadirachta indica, also known as Neem; and so forth.
Anacyclus pyrethrum, commonly referred to as Akarkara, is widely recognized in
ayurvedic system of Indian medicine for its medicinal properties including antimicrobial
effect, local anaesthetic effect and anti-inflammatory activity. It
contains an alkaloid, ‘Pellitorin’, which induces local anaesthesia. Traditional
animal experiments have confirmed the local anaesthetic activity. The other
components of Anacyclus pyrethrum extract include phenols, tannins and
flavonoids. The extract has been found to be useful in toothache, apnoea, paralysis
of the tongue and muscles of the throat and neuralgic afflictions of the teeth.
Olea europaea (Olive tree). is the most important fruit tree in the Mediterranean
region. Olea europaea. is widely studied for the beneficial effects of its oil on the
health of a large section of the world’s population. Its leaves contain secondary
metabolite compounds, such as Oleacein and Oleuropein that are responsible for
hypotensive activity, hypoglycemic activity, and increased blood flow in the
coronary arteries, relieving arrhythmia and preventing intestinal muscle spasms.
Researchers have also found out that Oleuropein, inhibits 'gram negative'
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bacteria that are responsible for oral diseases and tooth cavity. Olive leaf extracts
have shown an antibacterial and antifungal action, which suggest their potential as
antimicrobials in oral care formulations (Phenolic Compounds and Antimicrobial
Activity of Olive (Olea europaea L. Cv. Cobrançosa) Leaves,
Molecules 2007, 12(5), 1153-1162;).
The medicinal herb Acacia nilotica, commonly known by the name Babul or
Kikar, is another herb known for its beneficial effect on the oral cavity. Although
the tree is basically grown for its bark, extracts of its leaves, pods and gums also
have various uses in traditional medicine. The chemical constituents of Babul
include catechins, epicatechins, dicatechins, resins, tanin, epigallo-catechin, gallic
acid, leucocyanidine gallate, galactose and rhamnose. Mouthwashes made of
Babul tree extracts are used to relieve tonsillitis, and chewing the bark of the
Babul tree is extremely effective in keeping the gums and the teeth healthy.
Azadirachta indica, also known as Neem, is native to India and the Indian
subcontinent. Researchers have long realized the antibacterial and antifungal
properties of Neem tree extracts. Both oils and aqueous extracts of Neem
comprise strong antiseptic compounds; that destroy the bacteria that cause
cavities, halitosis, and gum disease. Neem’s powerful anti-microbial activity
makes it a well-known ingredient in toothpaste, mouthwash, and oral health
tonics.
In view of the above facts, using herbal extracts in oral care compositions is an
attractive preposition for combating the numerous maladies of the oral cavity and
maintaining oral health. However, oral care compositions containing herbal
extracts present a unique set of issues. For example, herbal extracts contain potent
antioxidants, which easily undergo oxidation and polymerization, thereby causing
unattractive discoloration of oral care compositions containing said extracts.
Further, degradation of the active components reduces the efficacy of said oral
care compositions. Still further, degradation of its key constituents may result in
phase separation, i.e. oozing out of liquid from a gel.
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Attempts have been made in prior art to solve the above shortcomings. For
instance, United States publication US 20070053851 A1 discloses a topical agent
with oral activity in the form of a tooth paste, a mouthwash or a mouthwash
concentrate comprising one or more green tea poly-phenols, wherein the water
content according to Karl Fischer is 7.5% w/w or less. The document discloses a
method to mitigate the problem of decomposition of substances sensitive to
oxidation and especially the discoloration of green tea poly-phenols.
United States publication US 20100008869 A1 discloses a method of suppressing
coloration of catechins, by adding, a water-soluble polymer which forms a waterinsoluble
complex with catechins in dentifrice compositions.
United States publication US 20060141072 A1 discloses low water tooth pastes
containing a variety of plant extracts such as rosemary and green tea extracts,
humectants, abrasive compounds, along with an additional antioxidant
component. The additional antioxidant compound is added to make the dentifrice
composition resistant to oxidation and browning.
United States Patent US 5094842 A discloses oral compositions, such as tooth
pastes which contain Vitamin C and a copper compound such as copper sulphate.
The tendency of these compositions to discolour, particularly if they also contain a
zinc compound such as zinc citrate, can be reduced, by the inclusion in the
compositions, a stannous compound such as stannous pyrophosphate.
On preparing an oral care compositions containing above herbal extracts, the
inventors of the present invention noticed syneresis, darkening and unattractive
discoloration, especially at elevated temperatures and during storage. Further,
there are no reports in the prior art, pertaining to the stabilization of herbal oral
care compositions containing extracts of Akarkara, Olive leaves, Neem, and
Babul, and preventing syneresis therein. Furthermore, an oral composition that
shows discoloration over time is despised by consumers who generally prefer a
white or transparent composition. Hence, it is desirable to provide oral care
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compositions, containing said herbal extracts that suppress syneresis and
discoloration on long term storage or exposure to high temperatures.
SUMMARY OF THE INVENTION
The present invention broadly relates to an herbal oral care composition and its
colour stabilization.
In accordance with an embodiment of the invention, there is provided an herbal
oral care composition, comprising:
(a) an herbal extract;
(b) a stabilizing substance; and
(c) additives;
wherein the stabilizing substance suppresses syneresis and discoloration of the
herbal oral care composition.
Preferably, the herbal extract is derived from Anacyclus pyrethrum (Akarkara),
Olea europaea (Olive) leaves, Acacia nilotica (Babul or Kikar), Azadirachta
indica (Neem) or combinations thereof, and present in an amount in the range
from 0.1 to 1.0%, and more preferably in an amount of 0.2%.
Preferably, the stabilizing substance is selected from an anti-oxidant, a source of
zinc ions, or combinations thereof and present in an amount in the range from 0.1
to 2.0%.
The herbal oral care composition, contains an anti-oxidant selected from the group
consisting of tocopheryl acetate, ascorbic acid, stannous compounds, stannates,
ammonium sulphate, butylated hydroxytoluene (BHT), sodium meta-bisulfite or
combinations thereof.
Further, the source of zinc ions is selected from the group consisting of zinc
acetate, zinc citrate, zinc gluconate, zinc oxide and combinations thereof.
Still further, the herbal oral care composition of the present invention comprises
additives selected from the group consisting of thickeners, humectants, water,
surfactants, abrasive polishing materials, preservatives, sweetening agents,
colouring agents, titanium dioxide, and combinations thereof.
Preferably, the thickener is selected from the group consisting of carboxyvinyl
polymers, carrageenan, hydroxyethyl cellulose, sodium carboxymethylcellulose,
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sodium carboxymethyl hydroxyethyl cellulose, gum karaya, xanthan gum, gum
arabic, gum tragacanth, colloidal magnesium aluminum silicate, finely divided
silica or thickening silica, and combinations thereof and present in an amount in
the range from 0.20 to 20.00%.
Preferably, the humectant is selected from the group consisting of glycerin,
sorbitol, polyethylene glycol, propylene glycol, edible polyhydric alcohols, and
combinations thereof, and present in an amount in the range from 5.00 to 70.00%.
Preferably, the surfactant is selected from the group consisting of anionic
surfactants, non-ionic surfactants, amphoteric surfactants, zwitterionic surfactants,
cationic surfactants, and combinations thereof, and present in an amount in the
range from 1.20 to 2.50%.
Preferably, the abrasive polishing material is selected from the group consisting of
silica gel, precipitated silica, abrasive silica, calcium carbonate, dicalcium
orthophosphate dihydrate, calcium pyrophosphate, tricalcium phosphate, calcium
polymetaphosphate, insoluble sodium polymetaphosphate, hydrated alumina,
particulate condensation products of urea and formaldehyde and combinations
thereof, and present in an amount in the range from 0.00 to 55.00%.
Preferably, the preservative is selected from the group consisting of methyl
paraben, sodium methyl paraben, sodium benzoate, ethyl paraben, propyl paraben
and combinations thereof, and present in an amount in the range from 0.10 to
1.00%.
The herbal oral care composition may be in the form of toothpaste, a gel, an
anhydrous toothpaste and a tooth serum gel.
BRIEF DESCRIPTION OF DRAWINGS
Figure 1. depicts a comparison between a silica based toothpaste containing zinc
salts (right, example 12) and a silica based toothpaste without zinc salts (left,
example 9).
Figure 2. depicts a comparison between a calcium carbonate based toothpaste
containing zinc salts (right, example 24) and a calcium carbonate based toothpaste
without zinc salts (left, example 22).
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Figure 3. depicts a comparison between a gel toothpaste containing zinc salts
(right, example 39) and a gel toothpaste without zinc salts (left, example 35).
Figure 4. depicts a comparison between an anhydrous toothpaste containing zinc
salts (right, example 45) and an anhydrous toothpaste without zinc salts (left,
example 42).
Figure 5. depicts a comparison between a tooth serum gel containing zinc salts
(right, example 49) and a tooth serum gel without zinc salts (left, example 47).
DETAILED DESCRIPTION OF THE INVENTION
Discussed below are some representative embodiments of the present invention.
The invention in its broader aspects is not limited to the specific details and
representative methods. The illustrative examples are described in this section in
connection with the embodiments and methods provided. The invention according
to its various aspects is particularly pointed out and distinctly claimed in the
attached claims read in view of this specification.
It is to be noted that, as used in the specification and the appended claims, the
singular forms "a," "an," and "the" include plural referents unless the context
clearly dictates otherwise. Thus, for example, a reference to a composition
containing “a compound” includes a mixture of two or more compounds. It should
also be noted that the term “or” is generally employed in its sense including
“and/or” unless the content clearly dictates otherwise.
The expression of various quantities in terms of “%” or “% w/w” means the
percentage by weight of the total solution or composition unless otherwise
specified.
All cited references are incorporated herein by reference in their entireties.
Citation of any reference is not an admission regarding any determination as to its
availability as prior art to the claimed invention.
Oral care compositions containing herbal extracts suffer from syneresis, darkening
and un-attractive discoloration, especially at elevated temperatures and on
prolonged storage. Moreover, consumer preferences towards oral care
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compositions have changed, who, now, generally prefer a white or transparent
composition. Hence, it is desirable to provide oral care compositions, containing
said herbal extracts that is free from the aforementioned drawbacks.
Accordingly, the inventors of the present invention have developed a novel
composition; comprising:
(a) an herbal extract;
(b) a stabilizing substance; and
(c) additives;
wherein the stabilizing substance suppresses syneresis and discoloration of the
herbal oral care composition.
Preferably, the herbal extract is present in an amount of 0.1 to 1%, and more
preferably in an amount of 0.2%. Examples of the plant species from which the
herbal extracts are derived include, but not limited to, Anacyclus pyrethrum
(Akarkara), Olea europaea (Olive) leaves, Acacia nilotica (Babul or Kikar), and
Azadirachta indica (Neem). These may be present either individually or in
combinations.
The term “stabilizing substance” used herein refers to a substance that prevents
discoloration and syneresis in a herbal oral care composition. Preferably, the
stabilizing substance is present in an amount of 0.1 to 2.0%. Stabilizing
substances that can be used in the herbal oral care compositions of the present
invention include anti-oxidants, a source of zinc ions, or combinations thereof.
Non-limiting examples of anti-oxidants include tocopheryl acetate, ascorbic acid,
stannous compounds, stannates, ammonium sulphate, butylated hydroxytoluene
(BHT), sodium meta-bisulfite and combinations thereof. The source of zinc ions
may include, but not limited to, zinc acetate, zinc citrate, zinc gluconate, zinc
oxide and combinations thereof.
Apart from herbal extracts, anti-oxidants and sources of zinc ions, the herbal oral
care composition, comprises additives selected from thickeners, humectants,
water, surfactants, abrasive polishing materials, sweetening agents, coloring
agents, titanium dioxide, and combinations thereof.
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The oral care compositions in the form of toothpastes, typically contain some
thickeners or binders to provide desirable consistency or viscosity. Examples of
thickeners include, but not limited to, carboxyvinyl polymers, carrageenan,
hydroxyethyl cellulose, sodium carboxymethylcellulose, sodium carboxymethyl
hydroxyethyl cellulose, gum karaya, xanthan gum, gum arabic, gum tragacanth,
colloidal magnesium aluminum silicate, finely divided silica or thickening silica,
and combinations thereof. The thickener is present in an amount in the range from
0.20 to 20.00%.
Another component of the composition desired herein is a humectant. The
humectants serve to keep an oral composition from hardening upon exposure to
air and certain humectants can also impart desirable sweetness to oral
compositions. Non-limiting examples of humectants that can be used in the
present invention include glycerin, sorbitol, polyethylene glycol, propylene glycol,
edible polyhydric alcohols, and so forth, each of which can be used individually or
in combination, in an amount in the range from 5.00 to 70.00%
Yet another important component of the present invention is a surfactant.
Depending on the property desired, in the oral composition, one or more suitable
surfactants may be present. Suitable surfactants are those which are reasonably
stable and foam throughout a wide pH range. The surfactant may be anionic,
nonionic, amphoteric, zwitterionic, cationic, or mixtures thereof. Anionic
surfactants useful herein include the water-soluble salts of alkyl sulfates having
from 8 to 20 carbon atoms in the alkyl radical (e.g., sodium alkyl sulfate) and the
water-soluble salts of sulfonated monoglycerides of fatty acids having from 8 to
20 carbon atoms. Sodium lauryl sulfate and sodium coconut monoglyceride
sulfonates are examples of anionic surfactants of this type. Other suitable anionic
surfactants are sarcosinates, such as sodium lauroyl sarcosinate, taurates, sodium
lauryl sulfoacetate, sodium lauroyl isethionate, sodium laureth carboxylate, and
sodium dodecyl benzenesulfonate. Mixtures of anionic surfactants can also be
employed. Non-ionic surfactants which can be used in the compositions of the
present invention can be broadly defined as compounds produced by the
condensation of alkylene oxide groups (hydrophilic in nature) with an organic
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hydrophobic compound which may be aliphatic or alkyl-aromatic in nature.
Examples of suitable nonionic surfactants include polyoxyethylene sorbitan esters,
fatty alcohol ethoxylates, polyethylene oxide condensates of alkyl phenols,
products derived from the condensation of ethylene oxide with the reaction
product of propylene oxide and ethylene diamine, ethylene oxide condensates of
aliphatic alcohols, long chain tertiary amine oxides, long chain tertiary phosphine
oxides, long chain dialkyl sulfoxides, and mixtures of such materials. The
amphoteric surfactants useful in the present invention can be broadly described as
derivatives of aliphatic secondary and tertiary amines in which the aliphatic
radical can be a straight chain or branched and wherein one of the aliphatic
substituents contains from about 8 to about 18 carbon atoms and one contains an
anionic water-solubilizing group, e.g., carboxylate, sulfonate, sulfate, phosphate,
or phosphonate. Other suitable amphoteric surfactants are betaines, specifically
cocamidopropyl betaine. Mixtures of amphoteric surfactants can also be
employed. The oral care composition of the present invention contains the
surfactant in an amount in the range from 1.20 to 2.50%.
An abrasive polishing material may also be included in the toothpaste
composition. The abrasive polishing material contemplated for use in the
compositions of the present invention can be any material which does not
excessively abrade dentine. These include, for example silica gel, abrasive silica,
precipitated silica, calcium carbonate, dicalcium orthophosphate dihydrate,
calcium pyrophosphate, tricalcium phosphate, calcium polymetaphosphate,
insoluble sodium polymetaphosphate, hydrated alumina, particulate condensation
products of urea and formaldehyde and combinations thereof. The abrasives are
present in an amount in the range from 0.00 to 55.00%.
A preservative may be included in the present invention to inhibit the growth of
microorganisms. Preservatives useful for use in the present invention include, but
not limited to, methyl paraben, sodium methyl paraben, sodium benzoate, ethyl
paraben, and propyl paraben. The preservative is present in an amount in the range
from 0.10 to 1.00%.
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Titanium dioxide, a white powder which adds opacity to the compositions, may
also be added to the present composition. Further, coloring agents may also be
added to the present composition. Still further, the composition of the present
invention may also contain sweetening agents selected from the group consisting
of sodium saccharin, dextrose, sucrose, chlorinated sucrose, lactose, maltose,
levulose, aspartame, sodium cyclamate, D-tryptophan, dihydrochalcones,
acesulfame, monoammonium glycyrrhizinate and combinations thereof.
The present invention is more particularly described in the following non-limiting
examples that are intended as illustrations only since numerous modifications and
variations within the scope of the present invention will be apparent to a skilled
artisan. Unless otherwise noted, all parts, percentages, and ratios reported in the
following examples are on a weight basis, and all reagents used in the examples
were obtained or made available from the chemical suppliers.
Examples 1-8
Table 1. Lists the ingredients and their amounts present in the oral care
composition of the present invention. The unit of each value is percent weight of
the composition. Ingredients are combined and mixed by conventional means as
known by one of ordinary skill in the art.
Table 1. Oral care compositions containing anti-oxidants
Ingredients 1 2 3 4 5 6 7 8
Extract of Akarkara
(Anacyclus pyrethrum)
0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2
Tocopheryl Acetate 0.0 0.1 0.2 0.5 0.0 0.0 0.0 0.0
Ascorbic Acid 0.0 0.0 0.0 0.0 0.1 0.2 0.5 1.0
Glyceirne 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0
Propylene glycol 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0
Preservatives 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50
Purified water qs qs qs qs qs qs qs qs
qs = quantity sufficient
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Examples 9-15
Table 2. Lists the ingredients and their amounts present in the oral care
composition of the present invention. The unit of each value is percent weight of
the composition. Ingredients are combined and mixed by conventional means as
known by one of ordinary skill in the art.
Table 2. Silica based toothpaste containing Zinc acetate or Zinc citrate
Ingredients 9 10 11 12 13 14 15
Extract of
Akarkara
(Anacyclus
pyrethrum)
0.2 0.2 0.2 0.2 0.2 0.2 0.2
Zinc acetate 0.00 0.5 1.0 2.0 0.00 0.00 0.00
Zinc citrate 0.00 0.00 0.00 0.00 0.5 1.0 2.0
Humectant 24.00 24.00 24.00 24.00 24.00 24.00 24.00
Thickener 1.00 1.00 1.00 1.00 1.00 1.00 1.00
Preservative 0.25 0.25 0.25 0.25 0.25 0.25 0.25
Sweetening agent 0.25 0.25 0.25 0.25 0.25 0.25 0.25
Thickening silica 6.90 6.90 6.90 6.90 6.90 6.90 6.90
Abrasive silica 13.50 13.50 13.50 13.50 13.50 13.50 13.50
Surfactant 2.20 2.20 2.20 2.20 2.20 2.20 2.20
Flavouring agent 1.20 1.20 1.20 1.20 1.20 1.20 1.20
Purified Water qs qs qs qs qs qs qs
qs = quantity sufficient
Examples 16-21
Table 3. Lists the ingredients and their amounts present in the oral care
composition of the present invention. The unit of each value is percent weight of
the composition. Ingredients are combined and mixed by conventional means as
known by one of ordinary skill in the art.
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Table 3. Silica based toothpaste containing Zinc gluconate or Zinc oxide
Ingredients 16 17 18 19 20 21
Thickening silica 6.90 6.90 6.90 6.90 6.90 6.90
Abrasive silica 13.50 13.50 13.50 13.50 13.50 13.50
Extract of Akarkara
(Anacyclus pyrethrum)
0.2 0.2 0.2 0.2 0.2 0.2
Zinc gluconate 0.5 1.0 2.0 0.00 0.00 0.00
Zinc oxide 0.00 0.00 0.00 0.5 1.0 2.0
Humectant 24.00 24.00 24.00 24.00 24.00 24.00
Thickener 1.00 1.00 1.00 1.00 1.00 1.00
Preservative 0.25 0.25 0.25 0.25 0.25 0.25
Sweetening agent 0.25 0.25 0.25 0.25 0.25 0.25
Surfactant 2.20 2.20 2.20 2.20 2.20 2.20
Flavouring agent 1.20 1.20 1.20 1.20 1.20 1.20
Purified water qs qs qs qs qs qs
qs = quantity sufficient
Examples 22-28
Table 4. Lists the ingredients and their amounts present in the oral care
composition of the present invention. The unit of each value is percent weight of
the composition. Ingredients are combined and mixed by conventional means as
known by one of ordinary skill in the art.
Table 4. Calcium carbonate based toothpaste containing Zinc acetate or Zinc
citrate
Ingredients 22 23 24 25 26 27 28
Calcium carbonate 38.00 38.00 38.00 38.00 38.00 38.00 38.00
Extract of
Akarkara
(Anacyclus
pyrethrum)
0.2 0.2 0.2 0.2 0.2 0.2 0.2
Zinc acetate 0.00 0.5 1.0 2.0 0.00 0.00 0.00
Zinc citrate 0.00 0.00 0.00 0.00 0.5 1.0 2.0
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Humectant 30.00 30.00 30.00 30.00 30.00 30.00 30.00
Thickener 1.00 1.00 1.00 1.00 1.00 1.00 1.00
Preservative 0.25 0.25 0.25 0.25 0.25 0.25 0.25
Sweetening agent 0.25 0.25 0.25 0.25 0.25 0.25 0.25
Abrasive silica 3.50 3.50 3.50 3.50 3.50 3.50 3.50
Surfactant 2.20 2.20 2.20 2.20 2.20 2.20 2.20
Flavouring agent 1.20 1.20 1.20 1.20 1.20 1.20 1.20
Purified Water qs qs qs qs qs qs qs
qs = quantity sufficient
Examples 29-34
Table 5. Lists the ingredients and their amounts present in the oral care
composition of the present invention. The unit of each value is percent weight of
the composition. Ingredients are combined and mixed by conventional means as
known by one of ordinary skill in the art.
Table 5. Calcium carbonate based toothpaste containing Zinc gluconate or
Zinc oxide
Ingredients 29 30 31 32 33 34
Calcium carbonate 38.00 38.00 38.00 38.00 38.00 38.00
Extract of Akarkara
(Anacyclus pyrethrum)
0.20 0.20 0.20 0.20 0.20 0.20
Zinc gluconate 0.5 1.0 2.0 0.00 0.00 0.00
Zinc oxide 0.00 0.00 0.00 0.5 1.0 2.0
Humectant 30.00 30.00 30.00 30.00 30.00 30.00
Thickener 1.00 1.00 1.00 1.00 1.00 1.00
Preservative 0.25 0.25 0.25 0.25 0.25 0.25
Sweetening agent 0.25 0.25 0.25 0.25 0.25 0.25
Abrasive silica 3.50 3.50 3.50 3.50 3.50 3.50
Surfactant 2.20 2.20 2.20 2.20 2.20 2.20
Flavouring agent 1.20 1.20 1.20 1.20 1.20 1.20
Purified Water qs qs qs qs qs qs
qs = quantity sufficient
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Examples 35-41
Table 6. Lists the ingredients and their amounts present in the oral care
composition of the present invention. The unit of each value is percent weight of
the composition. Ingredients are combined and mixed by conventional means as
known by one of ordinary skill in the art.
Table 6. Compositions of gel toothpaste containing Zinc acetate or Zinc
citrate
Ingredients 35 36 37 38 39 40 41
Thickening silica 6.90 6.90 6.90 6.90 6.90 6.90 6.90
Abrasive silica 13.50 13.50 13.50 13.50 13.50 13.50 13.50
Extract of Akarkara
(Anacyclus pyrethrum)
0.20 0.20 0.20 0.20 0.20 0.20 0.20
Zinc acetate 0.00 0.5 1.0 2.0 0.00 0.00 0.00
Zinc citrate 0.00 0.00 0.00 0.00 0.5 1.0 2.0
Humectant 55.00 55.00 55.00 55.00 55.00 55.00 55.00
Thickener 1.00 1.00 1.00 1.00 1.00 1.00 1.00
Preservative 0.25 0.25 0.25 0.25 0.25 0.25 0.25
Sweetening agent 0.25 0.25 0.25 0.25 0.25 0.25 0.25
Surfactant 2.20 2.20 2.20 2.20 2.20 2.20 2.20
Flavouring agent 1.20 1.20 1.20 1.20 1.20 1.20 1.20
Purified Water qs qs qs qs qs qs qs
qs = quantity sufficient
Examples 42-46
Table 7. Lists the ingredients and their amounts present in the oral care
composition of the present invention. The unit of each value is percent weight of
the composition. Ingredients are combined and mixed by conventional means as
known by one of ordinary skill in the art.
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Table 7. Compositions of anhydrous toothpastes containing a source of zinc
ions.
Ingredients 42 43 44 45 46
Extract of Akarkara
(Anacyclus pyrethrum)
0.2 2.0 0.2 0.2 0.2
Zinc acetate 0.00 2.0 0.00 0.00 0.00
Zinc citrate 0.00 0.00 2.0 0.00 0.00
Zinc Gluconate 0.00 0.00 0.00 2.0 0.00
Zinc Oxide 0.00 0.00 0.00 0.00 2.0
Thickener 1.00 1.00 1.00 1.00 1.00
Preservative 0.25 0.25 0.25 0.25 0.25
Sweetening agent 0.25 0.25 0.25 0.25 0.25
Surfactant 2.20 2.20 2.20 2.20 2.20
Flavouring agent 1.20 1.20 1.20 1.20 1.20
Thickening silica 6.90 6.90 6.90 6.90 6.90
Abrasive silica 13.50 13.50 13.50 13.50 13.50
Humectant qs qs qs qs qs
qs = quantity sufficient
Examples 47-52
Table 8. Lists the ingredients and their amounts present in the oral care
composition of the present invention. The unit of each value is percent weight of
the composition. Ingredients are combined and mixed by conventional means as
known by one of ordinary skill in the art.
Table 8. Compositions of tooth serum gel containing a source of zinc ions
Ingredients 47 48 49 50 51 52
Extract of Akarkara
(Anacyclus pyrethrum)
0.2 0.2 0.2 0.2 0.2 0.2
Zinc acetate 0.00 0.5 0.00 0.00 0.1 0.2
Zinc citrate 0.00 0.00 0.5 0.00 0.1 0.2
Zinc gluconate 0.00 0.00 0.00 0.5 0.00 0.00
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Glyceirne 8.0 8.0 8.0 8.0 8.0 8.0
Thickener 1.00 1.00 1.00 1.00 1.00 1.00
Propylene glycol 2.0 2.0 2.0 2.0 2.0 2.0
Preservatives 0.50 0.50 0.50 0.50 0.50 0.50
Purified water qs qs qs qs qs qs
qs = quantity sufficient
Process for preparing extract of Akarkara (Anacyclus pyrethrum):
1. Akarkara (Anacyclus pyrethrum) was dried and ground into coarse
powder.
2. Weigh approx 500 g of ground Akarkara (Anacyclus pyrethrum) and
extract with hydro-alcoholic (70:30) extraction media using hot extraction
technique.
3. After complete extraction, the extract was filtered using a buchner funnel
fitted with a vacuum pump.
4. After filtration, extract was concentrated to afford extract of Akarkara
(Anacyclus pyrethrum) in the form of a semi- solid.
Stability studies
The above compositions were kept at 60 °C for 1 week and 45 °C for a period of 6
months for determining their stabilities. The formulations stored at 10 °C and
room temperature served as control.
Oral care compositions containing neither anti-oxidants nor sources of zinc ions
suffered from syneresis and unattractive darkening on being stored at 60 °C for 1
week as shown in figures 1 to 5. Compositions 2 to 4 and 5 to 8 present reduced
darkening effects with increased concentrations of Tocopheryl acetate and
Ascorbic acid. Further, silica based toothpaste formulation containing 1.0% zinc
acetate had a stabilizing effect, whereas other zinc salts were found to be
ineffective. Likewise, a chalk based toothpaste formulation comprising 1.0% zinc
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acetate effectively mitigated darkening and syneresis whereas other sources of
zinc ions were marginally effective. In both the gel toothpaste and the tooth serum
gel, 0.5% zinc citrate was effective in preventing discoloration and syneresis
while other zinc salts were generally ineffective. Finally, zinc gluconate in a
concentration of 2% effectively stabilized an oral care formulation in the form of
an anhydrous toothpaste.
While particular embodiments of the composition of the present invention have
been illustrated and described, it would be obvious to those skilled in the art that
various other changes and modifications can be made without departing from the
spirit and scope of the invention. It is thereof intended to cover in the appended
claims such changes and modifications that are within the scope of the invention.

We claim:
1. An herbal oral care composition, comprising:
(a) an herbal extract;
(b) a stabilizing substance; and
(c) additives;
wherein the stabilizing substance suppresses syneresis and discoloration of
the herbal oral care composition.
2. The herbal oral care composition, as claimed in claim 1, wherein the
herbal extract is derived from Anacyclus pyrethrum (Akarkara), Olea
europaea (Olive) leaves, Acacia nilotica (Babul or Kikar), Azadirachta
indica (Neem) or combinations thereof, and present in an amount in the
range from 0.1 to 1.0%, preferably 0.2%.
3. The herbal oral care composition, as claimed in claim 2, wherein the
stabilizing substance is selected from an anti-oxidant, a source of zinc
ions, or combinations thereof and present in an amount in the range from
0.1 to 2.0%.
4. The herbal oral care composition, as claimed in claim 3, wherein the antioxidant
is selected from tocopheryl acetate, ascorbic acid, stannous
compounds, stannates, ammonium sulphate, butylated hydroxytoluene
(BHT), sodium meta-bisulfite or combinations thereof.
5. The herbal oral care composition, as claimed in claim 3, wherein the
source of zinc ions is selected from the group consisting of zinc acetate,
zinc citrate, zinc gluconate, zinc oxide and combinations thereof.
6. The herbal oral care composition, as claimed in claims 3, 4 and 5, wherein
the additive is selected from thickeners, humectants, water, surfactants,
abrasive polishing materials, preservatives, sweetening agents, colouring
agents, titanium dioxide, and combinations thereof.
7. The herbal oral care composition, as claimed in claim 6, wherein the
thickener is selected from the group consisting of carboxyvinyl polymers,
carrageenan, hydroxyethyl cellulose, sodium carboxymethylcellulose,
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sodium carboxymethyl hydroxyethyl cellulose, gum karaya, xanthan gum,
gum arabic, gum tragacanth, colloidal magnesium aluminum silicate,
finely divided silica or thickening silica, and combinations thereof and
present in an amount in the range from 0.20 to 20.00%.
8. The herbal oral care composition, as claimed in claim 6, wherein the
humectant is selected from the group consisting of glycerin, sorbitol,
polyethylene glycol, propylene glycol, edible polyhydric alcohols, and
combinations thereof, and present in an amount in the range from 5.00 to
70.00%.
9. The herbal oral care composition, as claimed in claim 6, wherein the
surfactant is selected from the group consisting of anionic surfactants, nonionic
surfactants, amphoteric surfactants, zwitterionic surfactants, cationic
surfactants, and combinations thereof, and present in an amount in the
range from 1.20 to 2.50%.
10. The herbal oral care composition, as claimed in claim 6, wherein the
abrasive polishing material is selected from the group consisting of silica
gel, precipitated silica, abrasive silica, calcium carbonate, dicalcium
orthophosphate dihydrate, calcium pyrophosphate, tricalcium phosphate,
calcium polymetaphosphate, insoluble sodium polymetaphosphate,
hydrated alumina, particulate condensation products of urea and
formaldehyde and combinations thereof, and present in an amount in the
range from 0.00 to 55.00%.
11. The herbal oral care composition, as claimed in claim 6, wherein the
preservative is selected from the group consisting of methyl paraben,
sodium methyl paraben, sodium benzoate, ethyl paraben, propyl paraben
and combinations thereof, and present in an amount in the range from 0.10
to 1.00%.
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12. The herbal oral care composition, as claimed in claims 1 to 11, wherein
said composition may be in the form of a toothpaste, a gel, an anhydrous
toothpaste and a tooth serum gel.