CLIAMS:1. A system for scavenging chemicals generated from smoke in a tobacco product, preferably a cigarette; said system comprising
(i) at least one or more carrier extending through a cigarette filter, said carrier being made from cotton or cellulose acetate or polymers and is in the form of a discrete thread, yarn, filament, strand, fiber or cord;
(ii) 1-20% by weight of actives namely antioxidants being present in the said carrier.
2. The system as claimed in claim 1, wherein said carrier is preferably one or more discrete cotton thread.
3. The system as claimed in claim 1, wherein said antioxidants are selected from the group consisting of phyto extracts, synthetic compounds and/or a combination thereof.
4. The system as claimed in claim 3, wherein phyto extracts are selected from the group consisting of extracts from rosemary, caffeine, lycopene, prenyl flavonoids, Camellia sinensis, alfalfa, onions, spinach, broccoli, kale, garlic, coriander, red bell peppers, beets, fruits, red grapes and seeds, white grapes and their seeds, oranges, strawberries, kiwi fruit, tomato, apple, cocoa and combinations thereof.
5. The system as claimed in claim 1, wherein said antioxidants are preferably selected from butylated hydroxyl toluene, butylated hydroxyl anisole, gallic acid, resveratrol, tert butyl hydroquinone, octyl gallate, lactone and a combination thereof.
6. The system as claimed in claim 1, wherein said actives are applied onto a carrier, which extends through the cigarette filter, with or without pretreatment of solvent.

7. The system as claimed in claim 1, wherein said antioxidants scavenges chemicals include smoke chemical constituents of smoke such as TSNA, B(a)P and free radicals.
8. The system as claimed in claim 1, wherein said cigarette with filter thread containing antioxidants is stable for atleast 6 months.
9. A method of scavenging chemicals generated from smoke in a tobacco product; said method comprising steps of
i) coating a carrier with 1-20% by weight actives such as antioxidants;
ii) providing said carrier into a cigarette filter such that the carrier extends through the cigarette filter, said carrier being made from cotton or cellulose acetate or polymers and is in the form of a discrete thread, yarn, filament, strand, fiber or cord;
such that the carrier with the antioxidants scavenge chemicals generated from smoke in the tobacco product in the range of 10-60%.
10. The process as claimed in claim 9, wherein said carrier is preferably one or more discrete cotton thread.
11. The process as claimed in claim 9, wherein said antioxidants are selected from the group consisting of phyto extracts, synthetic compounds and/or a combination thereof.
12. The process as claimed in claim 9, wherein phyto extracts are selected from the group consisting of extracts from rosemary, caffeine, lycopene, prenyl flavonoids, Camellia sinensis, alfalfa, onions, spinach, broccoli, kale, garlic, coriander, red bell peppers, beets, fruits, red grapes and seeds, white grapes and their seeds, oranges, strawberries, kiwi fruit, tomato, apple, cocoa and combinations thereof.
13. The process as claimed in claim 9, wherein said antioxidants are preferably selected from butylated hydroxyl toluene, butylated hydroxyl anisole, gallic acid, resveratrol, tert butyl hydroquinone, octyl gallate, lactone and a combination thereof.

14. The process as claimed in claim 9, wherein said antioxidants scavenges chemicals include smoke chemical constituents of smoke such as TSNA, B(a)P and free radicals.
,TagSPECI:FIELD OF THE INVENTION
The present invention relates to delivery of various antioxidants through cigarette filters. More particularly the invention relates to a system for delivering various antioxidants using filter thread route to tobacco containing smoking articles and methods thereof.

BACKGROUND AND THE PRIOR ART
Cigarette smoke contains free radicals which are undesirable. Cigarette filters are well known in the art to deliver antioxidants. Various approaches were made to reduce or quench free radicals in smoke using antioxidants.

KR100903951 discloses a cigarette filter containing ascorbic acid derivatives for reducing free radicals in mainstream smoke.

JP62232371, titled “Filter For Combustion Gas Of Tobacco” discloses a cigarette filter to which a radical scavenger such as benzoquinone and vitamin C are added. JPO6062824 discloses a method for removing free radical from tobacco smoke in which synthetic and natural antioxidants or mixture thereof at a concentration of 0.0001-100 mg preferably 0.1-10 mg were directly incorporated in the filter resulting free radicals in tobacco main stream smoke can be trapped or detoxified. JPO‘824’ teaches natural antioxidants as derived from fermented soybean such as ascorbic acid and synthetic antioxidants such as BHT, BHA etc. Scavenging activity as mentioned in JPO‘824’ is with reference to the removal of active oxygen species.

Removal of active oxygen species as disclosed in JPO‘824’ is 67% when synthetic antioxidant BHT directly incorporated into cigarette filter. Removal rate is further high as 81% when synthetic antioxidant is incorporated along with natural antioxidant into the cigarette filter.

However to quench all of the key radicals (R., RO. and ROO.) such as alkyl radicals, alkoxy radicals, peroxyl radicals and simultaneously reduce the levels of TSNA and B(a)P in main stream smoke (MSS) is unknown. ‘824 uses ESR spin trapping experiment (conventional method) which comes with an inherent limitations and is not sufficiently sensitive to peroxyl radicals (ROO.) which are considered to be the dominant radicals present in main stream smoke and also highly undesirable. Further ‘824 is silent about reduction in TSNA, B(a)P levels in main stream smoke.

Further JP2001526913 discloses a tobacco filter in which polyphenol compound obtained from plant extract such as rosemary extract in the range of 0.5mg to 0.5g preferably 0.002-0.1g more preferably 0.01g, is dissolved in solvent (ethanol) and introduced into cigarette filter. The solvent is later removed or evaporated from the filter. The system of JP‘913’ is capable of scavenging free radicals generated from tobacco smoke as 70%. Further, JP‘913’ discloses an alternative method for preparing such system wherein polyphenol compound is bonded with a carrier. The carrier as disclosed is being made from polystyrene polymer and is used in the form of micro-bead. However JP‘913’ mentions that said carrier increases the weight of polyphenol compound.

JP’913 however does not teach about reducing B(a)P and TSNA levels from the main stream smoke.

US2002074009 discloses a cigarette filter that has a scavenging effect on smoking induced gas phase free radicals. The filter ingredients are comprised of proanthocyanidins and include, but are not limited to, extracts of barks of pine tree, extracts of cones of cypress trees, extracts of grape seeds and any combination thereof. Also, vitamin C and other known antioxidant ingredients may be added. Example 1 of US2002074009 discloses a combination of proanthocyanidins and vitamin C (100%) in the proportion of 1:2 in a 95% ethanol solution. Such ethanol solution containing proanthocyanidins and vitamin C when sprayed over cigarette filaments and dried the gas phase free radical scavenging rate was in the range of 20%-29.1%.

Further US6207600 discloses a fiber containing remarkably high heat resistance and softness and fiber-processed products using the same. The fiber is formed from a polypropylene serving as at least one raw material. US6207600 mentions that the primary products can be secondarily processed to serve a wide range of uses including clothing, filter materials such as air filters, tobacco filters etc. US6207600 also mentions that additives such as antioxidant may be incorporated into polypropylene which is serving as a raw material of the fiber.

All above stated prior arts relating to delivering the antioxidants comprises several drawbacks and they are: direct injection of antioxidants onto the filter may lead to uneven distribution of actives. Further, antioxidants may also been added to the filters along with adsorbents / carrier molecules such as zeolites etc or using entrapment techniques which may lead to additional load of ingredients and also adds up process complexities.

Further menthol thread filter consists of an acetate filter with a flavored additive is also known in art. There are products available with flavoring agentslocated in the cigarette filter, e.g. mentholated “thread” in the middle. Several brands of such type of cigarette are available such as “Kent Citric Methol (BAT)” and “Salem Alaska Menthol”, “Seven Stars Cutting Menthol (JTI)” or “Silver Mint” and “Ice Mint” by Marlboro (PM).

Further there are a prior art which discloses, the reduction of free radical and tobacco-specific nitrosamines (TSNAs) by tea filter where the content of free radical in cigarette mainstream smoke was detected by ESR spectroscopy in conjunction with the spin trapping method. The experimental results showed that the contents of free radical in gas phase and solid phase of tea filter cigarette main stream smoke were reduced by 0.48% - 16.42 and 12.36-16.48%, respectively compared with regular filter cigarette. The tobacco-specific nitrosamines (TSNAs) were detected by gas chromatography thermal energy analyzer. The results indicated that the contents of NNN, NAT, NAB, NNK, and total TSNAs in tea filter flue-cured cigarette mainstream smoke were to be reduced by 16.88%, 15.12%, 26.04%, 11.39%, and 14.61% respectively. The contents of NNN, NAT, NAB, NNK and total TSNAs in tea filter blended cigarette mainstream smoke were to be reduced by 23.04%, 11.62%, 17.41%, 17.38%, and17.41% respectively. (Yao, Er-min; Zhang, Jun-song; Liang, Yong-lin, Chaye Kexue (2009), Journal of Tea Science, 29(2), 127-130). However, the results are found to be insignificant when it is delivered via conventional cigarette filter route. Thus there is a need to provide a method to deliver antioxidants to scavenge the free radicals and reduce TSNA and B(a)P through a non-conventional method such as cigarette filters thread route.

Delivering the flavors through a filter or filter thread has a different functionality which means the distribution of flavors need not be uniform. Further flavors have high vapor pressure and can easily evaporate and get released easily.

To overcome the above mentioned drawbacks there is a need to develop a system and method for delivering various antioxidants using filter thread preferably through an enhanced thread route that can be incorporated onto a tobacco containing combustible product formats such as cigarettes to scavenge chemicals generated from smoke and which also provides thermal stability and uniform distribution of the actives during manufacturing, storage and usage.

OBJECT OF THE INVENTION
It is an object of the invention to provide a system that uniformly delivers actives such as antioxidants through cigarette filters containing a carrier, such that the antioxidant scavenges chemicals generated from the smoke.

It is another object of the invention to provide a method of preparing the system.

It is yet another object of the present invention to provide a method of scavenging chemicals generated from smoke in tobacco product.

It is further an object of the invention to provide a method which allows adding the said actives onto a carrier which extends through the cigarette filter with or without pretreatment of solvents.

SUMMARY OF THE INVENTION
According to one aspect of the present invention there is provided a system for scavenging chemicals generated from smoke in a tobacco product, preferably cigarette; said system comprising;
(i) at least one or more carrier extending through a cigarette filter, said carrier being made from cotton or cellulose acetate or polymers and is in the form of a discrete thread, yarn, filament, strand, fiber or cord;
(ii) 1-20% by weight of actives namely antioxidants being present in the said carrier.

According to yet another aspect of the present invention there is provided a method of scavenging chemicals generated from smoke in a tobacco product; said method comprising steps of
i) coating a carrier with 1-20% by weight actives such as antioxidants;
ii) providing said carrier into a cigarette filter such that the carrier extends through
the cigarette filter, said carrier being made from cotton or cellulose acetate or polymers and is in the form of a discrete thread, yarn, filament, strand, fiber or cord;
such that the carrier with the antioxidants scavenge chemicals generated from smoke in the tobacco product in the range of 10-60%.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
Figure 1 illustrates the filter thread coated with antioxidants in accordance with the present invention;
Figure 2 illustrates the antioxidant property rendered by various actives measured through spectro- flourimetry method in accordance with present invention;
Figure 3 illustrates the reduction in levels of Tobacco Specific Nitroso Amines (TSNA) by the actives in comparison with the control in accordance with present invention;
Figure 4 illustrates the reduction in levels of Benzo[a]pyrene [B(a)P] by the actives in comparison to control in accordance with present invention.

DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a delivery system for delivering various antioxidants selected from the group consisting of phyto extracts, synthetic compounds and/or a combination thereof to the cigarette smoke through filter carrier route wherein said antioxidants being present in the range of 1-20 wt% and the range of scavenging chemicals from smoke is of at least 10-60%.

The carrier used in present invention being made from cotton or cellulose acetate or polymers and is in the form of a discrete thread, yarn, filament, strand, fiber or cord. The carrier used in present invention is preferably one or more discrete cotton thread.

The antioxidants used in present invention is plausible phyto extracts, selected from the group consisting of extract from rosemary, caffeine, lycopene, prenyl flavonoids, Camellia sinensis, alfalfa, onions, spinach, broccoli, kale, garlic, coriander, red bell peppers, beets, fruits, red grapes and seeds, white grapes and their seeds, oranges, strawberries, kiwi fruit, tomato, apple, cocoa.

The antioxidants used in present invention are preferably selected from butylated hydroxyl toluene (hereinafter after BHT), butylated hydroxyl anisole (hereinafter after BHA), gallic acid, resveratrol, tert butyl hydroquinone (hereinafter TBHQ), octyl gallate and lactone.

Solvent used in the present invention is propylene glycol (hereinafter PG) in the range of 80-99% by weight.

According to preferred embodiment of the present invention a method of scavenging chemicals generated from smoke in a tobacco product comprising steps of (i) coating a cotton thread with 1-20% by weight actives such as antioxidants; (ii) providing said cotton thread into a cigarette filter such that the cotton thread extends through the cigarette filter.

Chemical constituents generated from the main stream smoke includes free radicals, TSNA, and B(a)P. The present inventors have found that the antioxidant which is present in filter containing carrier, scavenges/quenches these chemicals in the range of 10-60%. It has been found that there is uniform distribution of antioxidants and reduction in free radicals, TSNA and B(a)P in mainstream smoke, i.e., these harmful radicals are not delivered to the smoker or to the environment. The absorbed free radicals are uniformly held in the filter.

Thus the present invention provides prevention of the free radicals from entering the body of the subject or disseminating to the environment by quenching the free radicals and retaining the same in the filter containing thread itself.

The present invention is now illustrated with a few representative but non-limiting examples.

Example 1
Incorporation of actives onto a filter rod:
A sample tray was prepared containing preferred actives at the concentration of 0.33 mg to 2.4 mg per filter plug. The cotton threads are dipped in the sample tray containing actives and the same are packed inside a filter tow. 1 filter rod equals to 108 mm which can be made into 4 filter plugs of each 27 mm. The wt% of actives that can be incorporated onto the 27 mm filter plug ranges between 0.33 mg to 2.4 mg.

Process of coating of antioxidant onto the filter:
12 mg of various concentrations of antioxidants as gallic acid (10% in PG), resveratrol (5% in PG), THBQ (20% in PG), octyl gallate (20% in PG) were applied onto the cellulose acetate filter via a cotton thread (obtained from Madura coats). Lactone was coated onto the thread without any propylene glycol as a neat because lactone used is a liquid in nature and has solvent properties by itself. Smoke characteristic of antioxidant coated filter was compared with control wherein no antioxidant was coated.

Example 2:
Experiments to show the stability of antioxidant in the solvent and filter:
In order to ascertain the ‘stability’ of antioxidant on the filter, analysis of representative antioxidants (12 mg of gallic acid in 10% PG and 12 mg Resveraterol in 5% PG) was carried out at two different time intervals using HPLC method-a known conventional method for such routine activities. Firstly at the time of the preparation of filter and secondly two weeks post preparation (antioxidants loaded on to the filter thread i.e. 1.2 mg of Gallic acid and 2.4 mg of resveratrol). Study confirmed that these antioxidants were quite stable (at least for 3 months) and did not decompose under the conditions.
Details of HPLC analysis:

Sample preparation:
Cigarette plug was separated from the cigarette and was taken in 50 mL erlenmeyer flask, treated with absolute ethanol (20 mL) and shaken for 1hr after which the solution was passed through 0.45 µm syringe filter. Filtrate was injected into HPLC-UV at 280 nm for quantification of gallic acid & resveraterol respectively.

HPLC conditions: Mobile phase A: 1.5% Ethyl acetate in 0.2% Ortho phosphoric acid in water; Mobile phase B: Methanol, Wave length: lmax- 280 nm, Column: Thermo, Synchronis, C18, 250 mm x 4.5 mm x 5 µm, Flow rate: 1 mL per min for 30 min. Gradient used is as below:

Time (min) A B
0.01 95 5
5 95 5
15 40 60
20 40 60
23 95 5
30 95 5

Results of HPLC quantification:
Antioxidant Observeda(2 weeks)Weight per filter Observeda(6 months)Weight per filter Expected weightPer filter
Gallic acid 0.9 mg 1.3 mg 1.2 mg
Resveraterol 0.5 mg 0.7 mg 0.6 mg
a - Single time un-optimized results. Observed increase in weight from 2 weeks to 6 months is within 20% analytical variability from the expected weight.

Example 3:
Studies to show the permeation of antioxidant from thread into the filter for a given solvent:
The radical scavenging activity of antioxidant attributes to the effectiveness of the antioxidant in Propylene glycol to distribute from thread into the filter. Representative concentrations of Gallic acid and Resveraterol in thread and filter were carried using HPLC and details are tabulated in table 1.
Gallic acid was found to penetrate to the extent of 59% into the thread and Resveraterol was found to penetrate to the extent of 74% into the thread. Lesser the quantity of antioxidants in thread indicates more penetration / permeation into the filter.

Table 1 - Study on permeation of antioxidant from thread into the filter:
Antioxidant % Remaining in thread % Remaining in filter
Gallic Acid 41% 59%
Resveraterol 26% 74%

Example 4
Experiments to show the free radical scavenging activity of antioxidants in accordance with the present invention.
Detection of reactive oxygen species (ROS) scavenging activity of ingredients in cigarette smoke was done through standard curve of Rhodamine 6G. The present inventors have prepared Rhodamine 6G stock (100 µM) by dissolving rhodamine 6G in dimethylacetamide (DMA) solution. The stock solution was serially further diluted to generate a series of dilutions ranging from 1 µM to 10µM in DMA solution. 100 µl of each standard was pipette out in duplicate into COSTAR 96 well flat bottomed black plate. Two wells pipetted with 100 µl of plain DMA solution acted as assay blank. Care was taken such that there are no bubbles in the wells. Fluorescent reading were taken in Varioskan Flash (photometric plate reader) with 526/546 nm as excitation/emission maxima. The resulting fluorescent readings were prepared plotted against the concentration of Rhodamine 6G to obtain the standard curve.

ROS converts dihydrorhodamine (DHR 6G) to rhodamine 6G which is highly fluorescent. The conversion of DHR 6G to rhodamine 6G is directly proportional to the amount of ROS present in the smoke. Cigarette smoke was bubbled through dihydrorhodamine (DHR 6G) containing trapping solution with different filter containing actives. The resultant trapping solutions were analyzed using fluorescence reader (Varioskan Flash) to check for the amount of rhodamine 6G production along with standards and required blanks as explained above in the standard curve plotting.

Preparation of smoke solution and determination of ROS:
Cigarette smoking was carried out according to ISO 3308 machine smoking standard conditions (35 mL puff, drawn for 2 seconds at 60 seconds intervals). 2 replicates (two cigarettes per replicate) of cigarettes in accordance with the present invention were smoked under ISO regime without using Cambridge filter. The cigarette smoke was then drawn through a single glass impinger that contained 30 mL of trapping solvent which consisted of 100 µM DHR-6G (8.8 mg in 200 mL with 3 drops of concentrated hydrochloric acid) of 60% DMA in 0.01 M phosphate buffer saline (PBS). For the determination of ROS yields, the fluorescence intensity of the smoke-bubbled solution was measured with an excitation maximum of 526 nm and an Emission maximum at 546 nm. Percentage of reduction in fluorescence intensity on test samples with respect to control sample was obtained as shown in Figure 2. According to Figure 2, gallic acid brings about 14.57% reduction, TBHQ brings about 43.57% reduction, octyl gallate 32.11% reduction and lactone brings about 36.54% reduction with respect to control.

Reduction of TSNA and B(a)P on modified filter:
Cigarette smoking was carried out according to ISO 3308 machine smoking standard conditions (35 mL puff, drawn for 2 seconds at 60 seconds intervals). 2 replicates (two cigarettes per replicate) of cigarettes in accordance with the present invention were smoked and the smoke was analyzed for TSNA and B(a)P reduction.

Figure 3 of the present invention demonstrated the reduction in levels of TSNA by the antioxidants in comparison to control.

Figure 4 of the present invention demonstrated the levels of B(a)P by the actives in comparison to control.

Example 5
The present inventors have conducted experiments to demonstrate that the percentage reduction of smoke chemical constituents such as TSNA, B(a)P is significant through cigarette filter thread route. Experiments were conducted with control (which has thread in the filter but without any antioxidant), cigarette samples in accordance with the present invention which are treated with TBHQ and Octyl gallate. These cigarettes were analyzed for TSNA and B(a)P amounts.
TSNA quantification involves by extracting 5 Cigarette smoke pads with Methanol (20 mL) containing deuteriated standard. An aliquot (5 µl) of extracted solution was injected for quantification by LCMS-MS Method, which is known in the art. Whereas, B(a)P quantification involves by extracting 5 Cigarette smoke pads with isoctane solvent (25 mL). Extraction was followed by SPE (Solid Phase Extraction) purification. Aliquot (1 µl in hexane) was injected for quantification by GC-MS-MS method, which is well known in the art. The results of the quantification is as shown below.

The control sample which is not treated with any antioxidants consists of 6.8 ng B(a)P/cig. When the same has been treated with TBHQ and Octyl gallate, there was 16% and 26% reduction respectively. Similarly, the control sample consists 243.4 ng/cig of TSNA, when the same is treated with TBHQ and octyl gallate, it got reduced to 53% and 56% respectively. It was observed that through cigarette filter thread route, the % smoke chemical constituents such as TSNA, B(a)P reduction is significant.