WO2013092117A2

WO2013092117A2 - An oral care composition

Info

Publication number: WO2013092117A2
Application number: PCT/EP2012/073591
Authority: WO
Inventors: Nandini BALARAM SINGH; Gautam Banerjee; Suresh Murigeppa NADAKATTI; Smitha Ashok Upadhyaya
Original assignee: Unilever N.V.; Unilever Plc; Hindustan Unilever Limited; Conopco, Inc., D/B/A Unilever
Priority date: 2011-12-20
Filing date: 2012-11-26
Publication date: 2013-06-27
Also published as: WO2013092117A3

Abstract

The present invention relates to an oral care composition more particularly to an oral care composition for anti-inflammatory benefit. Catechins in general are known for health benefit. In the world of tea, green tea is also well known for its health benefits. We have found that the catechins in general and those present in the green tea tend to be oxidized at the pH of the oral care composition and therefore no longer available to provide for the desired benefit. It is an object of the present invention to provide an oral care composition with minimum amount of catechins yet provide desired anti-inflammatory benefits. The present inventors while working with the oral care composition comprising catechins preferably green tea catechins for providing anti-inflammatory benefits, surprisingly found that very low amount of catechins when combined with black tea extract in a particular ratio is able to provide the desired anti-inflammatory benefits.

Description

AN ORAL CARE COMPOSITION Technical field of the invention: The present invention relates to an oral care composition more particularly to an oral care composition for anti-inflammatory benefit.

Background of the invention: Oral care and oral hygiene is one of the most important requirements for a healthy life. Everyday most of the people brush their teeth to keep themselves orally hygienic. Many people brush their teeth at least twice each day and sometimes even more than twice. On the other hand due to lack of proper dental care a number of people suffer from inflammation in their gums which causes irritation and diseases in their mouth. The most commonly known oral care compositions are toothpaste, tooth powder and mouthwash. People throughout the world use these compositions for their oral health and hygiene.

Efforts have been made to incorporate plant extracts and/or antibacterial agents in toothpaste compositions to combat oral inflammation.

US2006/0140881 (COLGATE-PALMOLIVE COMPANY, 2006) discloses an oral care composition containing: a free-B-ring flavonoids and a flavan; as well as at least one bioavailability-enhancing agent. Methods of using the oral compositions are also provided.

US2008/069783 (WANG JIUN ER, 2008) discloses an oral cavity cleaning composition, comprising 35-50 parts by weight of tea leaves extract, 10-25 parts by weight of Stevia leaf extract, 10-25 parts by weight of lemon extract, 10-15 parts by weight of mint leaf extract, 10-20 parts by weight of Lonicerae Flos extract, 20-30 parts by weight of kuding tea leaf extract, 5-10 parts by weight of xylitol and 25-35 parts by weight of ethanol. All ingredients in the composition are obtained from edible plants that are very effective in oral cavity care.

Catechins in general are known for their health benefit. In the world of tea, green tea is also well known for its health benefits. We have found that the catechins in general and those present in the green tea tend to be oxidized at the pH of the oral care composition and therefore no longer available to provide for the desired benefit. Therefore there is a need for developing an oral care composition containing catechins (such as green tea catechins) which is able to provide desired antiinflammatory benefit.

Objects of the invention:

In view of the foregoing, one of the objects of the present invention is to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a suitable alternative. It is yet another object of the present invention to provide an anti-inflammatory oral care composition.

It is a further object of the present invention to provide an oral care composition containing green tea which provides the desired anti-inflammatory benefits.

The present inventors while working with oral care compositions comprising green tea surprisingly found that low amount of green tea when combined with black tea extract in a particular ratio is able to provide the desired antiinflammatory benefits thereby satisfying one or more of the aforesaid objects.

Summary of the invention: According to a first aspect of the present invention there is provided an oral care composition comprising:

a) 0.01 to 5% by weight of green tea extract of Camellia sinensis species, b) 0.01 to 5% by weight of a black tea extract of Camellia sinensis

species ; and

c) an orally acceptable base,

wherein the amount of polyphenols in the black tea extract is from 25 to 40% by dry weight and the ratio of green tea extract to polyphenols in the black tea extract is from 1 :1 to 1 :50.

According to a second aspect the present invention provides a process of making an oral care composition comprising the steps of mixing 0.01 to 5% by weight of green tea extract of Camellia sinensis and 0.01 to 5% by weight of a black tea extract of Camellia sinensis with an orally acceptable base, wherein the amount of polyphenols in the black tea extract is from 25 to 40% by dry weight and the ratio of green tea extract to polyphenols in the black tea extract is from 1 :1 to 1 :50. According to a third aspect the present invention provides the use of an oral care composition of the first aspect for anti-inflammatory benefit.

According to a preferred aspect the present invention provides an oral care composition of the first aspect wherein the source of catechins is a green tea extract of Camellia sinensis.

These and other aspects, features and advantages will become apparent to those of ordinary skill in the art from a reading of the following detailed

description. For the avoidance of doubt, any feature of one aspect of the present invention may be utilised in any other aspect of the invention. It is noted that the figures given in the description below are intended to clarify the invention and are not intended to limit the invention to those figures per se. Similarly, all

percentages are weight/weight percentages unless otherwise indicated. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use are to be understood as modified by the word "about". Numerical ranges expressed in the format "from x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "from x to y", it is understood that all ranges combining the different endpoints are also

contemplated.

Detailed description of the invention:

The present invention provides an oral care composition comprising:

species ; and

c) an orally acceptable base,

The oral care composition of the invention comprises 0.01 to 5%, preferably 0.1 to 5% and more preferably 1 to 4% by weight of green tea extract. The source of green tea extract is Camellia sinensis.

Green tea is well known in the world of teas. Generally green tea is produced by steaming or pan-firing the tea leaves immediately after plucking so that enzyme action is inhibited and endogenous components in the leaves are retained in the product mainly unchanged. Therefore, the taste is primarily determined by the choice of clone, time of the plucking, shoot maturity and the cultivation method. Major constituents of green tea polyphenols are (-) epicatechin, (-)

epigallocatechin, (-) epicatechingallate and epigallocatechingallate (EGCG).

The preferable source of catechins for the composition of the present invention is green tea extract. The green tea extract is preferably fine granulated and comprises Gallic acid, catechins and their derivatives viz. Gallic acid,

Epigallocatechin (EGC), Epicatechin gallate (ECG), Epigallocatechin gallate (EGCG), Caffeine, and Catechins. The green tea extract preferably used for making the oral care formulation of the invention comprises 50 to 75 %, preferably 55 to 75% and more preferably 60 to 75% of polyphenols by dry weight of green tea extract.

The green tea extract preferably used for making the oral care formulation of the invention comprises 8 - 14 % of Epigallocatechin by dry weight of green tea extract, preferably 9 -14 % and more preferably 10 - 14%.

The green tea extract preferably used for making the oral care formulation of the present invention comprises 25 - 40%, preferably 28 - 40% and more preferably 32 - 40% of Epigallocatechin gallate by dry weight of green tea extract.

The green tea extract preferably used for making the oral care formulation of the present invention comprises 2 - 8%, preferably 3 - 8% , more preferably 4 - 8% and most preferably 5 -8% of Epicatechin gallate by dry weight of green tea extract.

The Epicatechins content of the green tea extract is between 2 - 8 %, preferably 3 - 8 % and more preferably 4 - 8 % by dry weight of the green tea extract.

The caffeine content of the green tea extract is in between 6 - 14%, preferably 8 - 14% and more preferably 10 - 14%. The green tea extract is from Camellia sinensis var. sinensis and/or Camellia sinensis var. assamica. Commercially available green tea powder with the particular specification as stated above (in terms of polyphenols, EGC, EGCG, ECG content) may be used for making the oral care composition. Alternatively instead of green tea extract, purified green tea catechins may be used.

The oral care composition of the present invention also comprises 0.01 to 5%, preferably 1 to 5% and more preferably 1 to 4% of black tea extract of Camellia sinensis. The black tea extract comprises 25 - 40%, preferably 28 - 40% and more preferably 30 - 40% of polyphenols by dry weight of black tea extract.

The aqueous extract of black tea is preferably made by extracting black tea leaf with water in a ratio of 1 :5 to 1 :30 at a temperature of 80 - 98°C for 10 minutes to 2 hours. After the extraction process preferably the extract is subjected to centrifugation to separate out the residual leaf and the aqueous extract. Then the aqueous extract is dried preferably in a spray dryer to get black tea extract powder. Optionally black tea extract in liquid form may be used for making the compositions of the invention.

The preferred ratio of one or more catechins to polyphenols in the black tea extract is from 1 : 10 to 1 :50 and more preferably from 1 : 15 to 1 :50.

The oral care composition of the invention comprises an orally acceptable base. The orally acceptable base is a base formulation which is suitable for application in the human mouth. The oral compositions can be formulated in any suitable form, such as gels, mouthwashes, toothpowders and toothpastes.

The oral care compositions of the present invention may comprise optional, conventional ingredients such as pharmaceutically acceptable carriers like starch, sucrose, water or water/alcohol systems etc.. Small amounts of surfactants may also be included, such as anionic, nonionic and amphoteric surfactants. The oral care composition may contain all the usual oral care composition ingredients. They may also comprise particulate abrasive materials such as silicas, aluminas, calcium carbonates, dicalcium phosphates, calcium pyrophosphates

hydroxyapatites, trimetaphosphates, insoluble hexametaphosphates or agglomerated particulate abrasive materials. Furthermore, the oral care composition may comprise humectants such as glycerol, sorbitol, propylene glycol, xylitol, lactitol and so on.

Binders and thickeners such as sodium carboxymethyl-cellulose, xanthan gum, gum arabic etc. may also be included, as well as synthetic polymers such as polyacrylates and carboxyvinyl polymers such as Carbopol.

Flavours, such as peppermint and spearmint oils may also be included, as well as preservatives, opacifying agents, colouring agents, pH-adjusting agents, sweetening agents and so on.

Anti-bacterial agents may also be included such as Triclosan, chlorhexidine, copper-, zinc- and stannous salts such as zinc citrate, sodium zinc citrate and stannous pyrophosphate, sanguinarine extract, metronidazole. Further examples of anti-bacterial agents are quaternary ammonium compounds such as cetylpyridinium chloride; bis-guanides such as chlorhexidine digluconate, hexetidine, octenidine, alexidine; halogenated bisphenolic compounds such as 2,2' methylenebis-(4-chloro-6-bromophenol).

Polymeric compounds which can enhance the delivery of active ingredients such as anti-bacterial agents can also be included. Examples of such polymers are copolymers of polyvinylmethylether with maleic anhydride and other similar delivery enhancing polymers.

Anti-caries agents such as sodium- and stannous fluoride, aminefluorides, monosodium fluorophosphate, casein, plaque buffers such as urea, calcium lactate, calcium glycerophosphate, strontium polyacrylates may also be included. Other optional ingredients include vitamins such as Vitamin C, and plant extracts. Desensitising agents such as potassium citrate, potassium chloride, potassium tartrate, potassium bicarbonate, potassium oxalate, potassium nitrate as well as strontium salts may also be included.

Buffers and salts to buffer the pH and ionic strength of the compositions may also be included. The pH of the compositions usually ranges from 5-10, preferably 6-9 and especially preferably 7-8.5.

Liposomes and other encapsulates may also be used to improve delivery or stability of active ingredients.

Furthermore, the oral compositions may comprise anti-calculus agents such as alkalimetal pyrophosphates, hypophosphite-containing polymers, organic phosphonates, phosphocitrates etc..

In addition, the compositions may comprise functional biomolecules such as bacteriocins, antibodies, enzymes and so on.

Other optional ingredients that may be included are effervescing systems such as sodium bicarbonate/citric acid systems, colour change systems, and so on.

When formulated as a mouthwash, the oral care composition usually comprises a water/alcohol solution, flavour, humectant, sweetener and colorant. The present invention also provides for a process of making an oral care composition comprising the steps of mixing 0.01 to 5% by weight of green tea extract of Camellia sinensis and 0.01 to 5% by weight of a black tea extract of Camellia sinensis with an orally acceptable base, wherein the amount of polyphenols in the black tea extract is from 25 to 40% by dry weight and the ratio of green tea extract to polyphenols in the black tea extract is from 1 :1 to 1 :50.

Preferably, the process comprises the steps of mixing 0.1 to 5%, more preferably 1 to 4 % of green tea extract and 0.1 to 5%, preferably 1 to 4 % of black tea extract of the Camellia sinensis species with an orally acceptable base. The amount of polyphenols in the black tea extract is from 25 to 40%, preferably 28 to 40% and more preferably 30 to 40% by dry weight, and the ratio of one or more catechins to polyphenols in the black tea extract is from 1 :1 to 1 :50 preferably 1 : 10 to 1 :50 and more preferably from 1 : 15 to 1 :50.

The mixing may be preferably carried out in a conventional mixer used for making such formulation. Sileverson® mixer is the preferred one.

The present invention also provides the use of an oral care composition as for anti-inflammatory benefit.

Now, the invention will be demonstrated with the help of following non-limiting examples.

Examples

Example 1 : Preparation of an oral care composition of the invention

Toothpaste compositions were made according to the formulations in Table 1. Table 1

Ingredient Amount (g) Ex. 1A Ex. 1 B Ex. 1 C

Sodium Nitrate 0.50 0.50 0.50

Saccharin 0.25 0.25 0.25

Sorbitol (70% solution) 15.00 15.00 15.00

FGNC 43.30 43.30 43.30

SCMC 0.62 0.62 0.62

Mfil 3.17 3.17 3.17

SLS 2.50 2.50 2.50

Green tea extract 1.5 0.5 0.1

Black tea extract 1.5 2.5 2.9

Na-Silicate (30% solution) 1.75 1.75 1 .75

SMFP 1.12 1.12 1 .12

Water To 100 To 100 To 100

Sodium carboxymethyl cellulose (SCMC) was added to water and then the solution was stirred for 15 minutes in a mixer toensure its complete solubilisation. Then sodium nitrate, Saccharin and 70% sorbitol solution were added one after another followed by mixing after addition of each ingredient. After that sodium lauryl sulfate (SLS) was added and mixed well till it dissolved completely. Then Fine ground natural chalk (FGNC), silica (trade name- Mfil®, supplier - Madhu silica pvt. Ltd., India), sodium silicate and sodium monofluorophosphate (SMFP) were added one after another and mixed well to assure the homogeneity of the paste. This was followed by addition of Green tea extract powder (Trade name - Sunphenone® having a polyphenol content of ~ 60%, EGCG content -32%, ECG content ~ 6.7%, EGC content ~ 12.8% and EC content of ~ 5% by dry weight, Supplier- Taiyo Green Power Co Ltd., Japan) and black tea extract powder (having a polyphenol content of ~ 30 %). Then mixing was continued for 5 minutes.

The black tea extract powder was made by taking Lipton® Yellow label leaf tea product available in the market. The leaf tea was extracted with water in a ratio of 1 :20 at a temperature of 92±2°C for 45 minutes. The extract was subjected to ultra filtration to obtain concentrated extract and then it was dried in a spray dryer to obtain the black tea extract powder. Example 2: Conversion of green tea catechins at high pH of the toothpaste

A toothpaste was made using the formulation of Table 1 , except instead of both black tea extract and green tea extract, only green tea catechins were added at a level of 5% by dry weight of the toothpaste. This toothpaste was stored in a tube at ~25°C and the catechin content was measured after 4 months and 1 1 months using the ISO method for the determination of catechins, using high performance liquid chromatography (ISO 14502-2:2005). The results are summarized in Table 2. The pH of the toothpaste was 9.

Table 2

From Table 2 it is evident that the catechin content decreases with time at the pH of the toothpaste, i.e. the toothpaste which contains a high amount of catechins is susceptible to destabilization of catechins. Example 3: ln-vitro experiments showing that a combination of green tea catechins and black tea extract provides anti-inflammatory benefits

Fresh blood was withdrawn by vein puncture from healthy volunteers (free of infection) and collected into a vacutainer containing heparin (to prevent coagulation of the samples).

RPMI medium was prepared by mixing 10.4 g of RPMI-1640 (from Sigma having Cat. No. 6504), 1 .5 g of sodium bicarbonate (from SRL), 2.5 g of glucose and 2.38 g of Hepes (from Sigma) in 900 mL of autoclaved Mili-Q water. After adjusting the pH to ~ 7.2, the solution was filtered using a membrane filter (from Pall Corporation, Specification - vacucap 90pf filter unit, pore size 0.2 micron), followed by adding 10 mL of antibiotic-antimycotic solution (from Sigma, Cat No. A5955). Finally the volume was made up to 1 L with autoclaved Mili-Q water.

1 mL of the fresh blood was diluted in 6.5 mL of RPMI medium. Then the diluted blood was distributed in a 24 well culture plate (0.5 mL / well). Test samples containing different amounts of green tea catechins (GT), black tea extract (BT) and mixtures of both (GT + BT) were prepared. The amounts are shown in Table 3. The black tea extract (BT) used had a total polyphenols content of -30.2%. The green tea catechins (GT) used above was supplied by Taiyo Green Power Co Ltd., Japan under the brand name of Sunphenone®. The green tea catechins had an EGCG content of ~ 32.4 %, EGC ~ 12.8%, ECG ~ 6.7% , TPP ~ 60% and caffeine ~ 1 1 .7% by dry weight of the green tea catechins powder.

0.5 mL / well of each test sample (as shown in Table 3) which has 100 μί of Escherichia coli lipopolysaccharide (E. coli LPS from Sigma, Cat. No. L-4130) was added to the wells in the culture plate. The concentration of LPS was 100 ng/mL, diluted in RPMI medium. A control well (C-1 ) was maintained in which there was no LPS (i.e. only 0.5 mL of blood and 0.5 mL of RPMI medium) and another control (C-2) with only LPS (0.5 mL of blood with 0.5 mL of RPMI medium containing 100 μΙ of LPS) was maintained separately. The culture plate was then incubated in an incubator (Forma series II water jacket CO₂ incubator: Thermo Scientific) at a temperature of ~37°C with 5% CO₂ for 24 hours. After incubation the culture plate was centrifuged at 1900 g for ~ 10 minutes. The supernatant was then collected and aliquoted (in tubes) and stored in a freezer maintained at -70°C for 12 hours. A 96-well microtiter plate (Nunc-lmmuno Plates MaxiSorp F96, Cat. No. 468667) was taken and coated with a solution of 100μΙ_ / well (concentration: 2μ9/ηιΙ_) of primary antibody (antihuman IL-6, R& D Systems, cat no AF-206-NA). After that the plate was kept for 12 hours at a temperature of ~ 4°C without any

disturbance.

The tubes containing supernatant were taken out and thawed at room

temperature (~25°C). Then the supernatant was diluted with RPMI medium (1 μΙ_ of supernatant with 10 μΙ_ of RPMI medium).

The 96 well plate was taken out from the refrigerator and washed with 300μΙ_ / well of wash buffer. The wash buffer was prepared by adding 0.05% (v/v) of Tween 20 in 500 ml_ of phosphate buffered saline (4 g NaCI + 0.1 g KCI + 0.58 g Na₂HP0₄ + 0.1 g KH₂P0₄ in 500 ml_ of autoclaved Mili-Q water). The washing step was done three times. The plate was then drained completely till all the liquid was removed. Then the plate was blocked with 300μΙ_ / well of 5% (w/v) skimmed milk in phosphate buffered saline (PBS) for 2 hours at ~25°C. The washing step was repeated three times. In the 96 well plate 100μΙ_ / well of human IL-6 standard (R&D Systems; Cat. No. 206-IL-050) ranging from 0.075ng/ml_ to 4.8ng/ml_ (prepared in PBS) was added to the first two strips and diluted culture supernatant (prepared above) was added in the remaining strips (all in duplicates). The plate was then incubated for 2 hours at ~25°C. The washing step mentioned above was repeated again thrice. The plate was then drained out completely. After that, 100μΙ_ / well (concentration O^g/mL) of human biotinylated antibody IL-6 (R&D Systems; Cat. No. BAF-206) was added to the plate. The plate was again incubated for 2 hours at ~25°C. The washing step mentioned above was repeated again thrice. The plate was then drained out completely. After that 100 L/well of 1 :200 diluted (in PBS) streptavidin-HRP conjugate (R & D Systems cat no DY 998) was added to the plate. The plate was then incubated for 30 minutes at 25°C. The washing and draining out step were repeated. This was followed by adding 100μΙ_ / well of 20 times water diluted TMB/H₂0₂ substrate (Bangalore Genei, Cat No. 106035). This plate was incubated in a dark room for 10 - 20 minutes for colour development. The reaction was then stopped by adding 50 μΙ_ / well of H₂S0₄ having a normality of 2N.

Then the OD (optical density) of the wells was measured at a wavelength of 450nm using Micro Plate Reader (BIO RAD, Model no 680).

The slope (A) of the standard curve (first two stripes of the plate using IL-6 standard) was calculated from the measured OD. The amount of IL-6 released (ng/mL) from the sample can be calculated with the use of the following formula:

Amount of IL-6 released = Absorbance (O.D) of the sample X-^

The results of the experiment are summarized below in Table 3, which shows the IL-6 release for GT catechins alone, BT alone and GT catechins + BT. The lower the IL-6 value the better the composition is at providing anti-inflammatory benefits.

Table 3

Concentration

IL - 6 (ng/mL) (in the test sample) Ratio of GT IL - 6 (ng/mL)

(Controls) catechins to BT

/o /o (Test Samples) polyphenols

catechins polyphenols

C-1 C-2 GT BT GT BT GT Cat

Catechins Cat. + BT

0.0035 0.0034 1 :1 13.2 ± 12.9 ± 7.5 ±

2.0 ± 15.01 ± 1 .0 1 .9 0.02 0.5 1.77 0.0049 0.00476 1 :1 1 1.58 ± 10.78 ± 6.62 ±

1.34 0.42 0.0

3.57 ± 42.65 ± 0.007 0.0068 1 :1 18.4 ± 25.05 ± 3.4 ± 1.14 9.8 7.03 7.73 1.19

0.0007 0.017 1 :24 44.18 ± 34.44 ± 12.36 ± 3.7 2.62 3.28

0.0007 0.034 1 :49 44.18 ± 12.46 ± 1 .52 ±

5.46 ± 47.53 ± 3.7 4.52 0.56 2.24 3.68

0.0007 0.000034 20:1 44.1 ± 43.55 ± 48.66 ±

6.4 6.6 8.2

0.0007 0.0000068 100:1 43.2 ± 43.2 ± 48.6 ±

6.8 6.8 7.5

From the above table it is evident that green tea catechins and black tea extract in a ratio within the scope of the present invention reduces the inflammation at much higher degree when compared to green tea catechins alone, black tea extract alone and combination of both at a ratio outside the scope of the present invention. It should be appreciated that this is an in-vitro assay, with low concentrations of GT catechins and BT extract (% polyphenols). It is expected that these concentrations at the cellular level would extrapolate to the concentration of these ingredients as claimed.

Example 4: ln-vivo experiments to show that a combination of green tea catechins and black tea extract provides plaque reduction benefits

The volunteers for this study were selected on the basis of their oral health (i.e. without any oral inflammation) and medical history. The study was conducted for 14 days (7+7) in two phases. During this period they were asked not to use any oral care product other than what was supplied to them for the study.

In the first phase, the mouth was rinsed with citrate buffer (sodium citrate and citric acid at a ratio of 1 :10) of concentration 75 mM, pH~5.5, for 30 sec. using 20 ml_ of the sample 3 times a day for 7 days. They were asked to brush the mouth (as usual, twice in a day) using the toothpaste provided for the study which did not include any anti microbial agent (only the base formulation). Then the plaque index was assessed at the t=0 (at start), t=7 days and the difference in the index was determined, which represents decrease in plaque index. In the second phase, the same procedure was repeated for next 7 days with the same volunteers with the test sample which was 1 .5% (based on polyphenols content) of black tea extract + 1 .5% green tea catechins mixed in the same citrate buffer. For this test sample the green tea catechins and black tea extract was the same as disclosed in Example 1 .

The plaque index was assessed by oral care experts using the procedure generally known to dentists. The results of the experiments are summarized in Table 4:

Table 4

From Table 4, it is clear that a combination of green tea catechins and black tea extract provides much higher reduction in plaque index than the control.

Claims

Claims:

1. An oral care composition comprising:

species; and

c) an orally acceptable base,

2. An oral care composition as claimed in claim 1 wherein the green tea

extract comprises 50 to 75 % polyphenols by dry weight of green tea extract

3. An oral care composition as claimed in claim 1 or 2 wherein the green tea extract comprises 8 - 14 % of Epigallocatechin by dry weight of green tea extract.

4. An oral care composition as claimed in any one claims 1 to 3 wherein the green tea extract comprises 25 - 40% of Epigallocatechin gallate by dry weight of green tea extract.

5. An oral care composition as claimed in any one of the preceding claims wherein the green tea extract comprises 2 - 8% of Epicatechin gallate by dry weight of green tea extract.

6. An oral care composition as claimed in any one of the preceding claims wherein the black tea extract is a water extract.

7. An oral care composition as claimed in any one of the preceding claims wherein the pH of the composition is from 5 to 10. A process of making an oral care composition comprising the steps of mixing 0.01 to 5% by weight of green tea extract of Camellia sinensis and 0.01 to 5% by weight of a black tea extract of Camellia sinensis with an orally acceptable base, wherein the amount of polyphenols in the black tea extract is from 25 to 40% by dry weight and the ratio of green tea extract to polyphenols in the black tea extract is from 1 :1 to 1 :50.

Use of an oral care composition as claimed in any one of claims 1 to 7 for anti-inflammatory benefit.