U.S. patent application number 11/919217 was filed with the patent office on 2009-11-05 for cigarette filter capable of removing harmful substance.
This patent application is currently assigned to NISSEI BIO CO., LTD.. Invention is credited to Xiang Dong Liu, Masaji Matsunaga, Norio Nishi.
Application Number | 20090272392 11/919217 |
Document ID | / |
Family ID | 37307669 |
Filed Date | 2009-11-05 |
United States Patent
Application |
20090272392 |
Kind Code |
A1 |
Liu; Xiang Dong ; et
al. |
November 5, 2009 |
Cigarette filter capable of removing harmful substance
Abstract
[PROBLEMS] To provide a cigarette filter that does not impair
the distinctive flavor of a cigarette and the air permeability of
filter while smoking, and at the same time, can more effectively
remove harmful substances such as a pyrene that is generated from
the cigarette. [MEANS FOR SOLVING PROBLEMS] The cigarette filter
comprising a filter fiber bundle body which cigarette smoke passes
through; a fine powder with a high surface area ratio that are
mixed and scattered in the filter fiber bundle body; and a
double-stranded DNA molecule attached to the outer surface of the
fine powder with a high surface area ratio, characterized in that
harmful substances such as benzo[a]pyrene contained in the
cigarette smoke can be removed by intercalation into the
double-stranded DNA molecule.
Inventors: |
Liu; Xiang Dong;
(Sapporo-shi, JP) ; Matsunaga; Masaji; (Sumida-ku,
JP) ; Nishi; Norio; (Sapporo-shi, JP) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 320850
ALEXANDRIA
VA
22320-4850
US
|
Assignee: |
NISSEI BIO CO., LTD.
Eniwa-shi
JP
NATIONAL UNIVERSITY CORPORATION hOKKAIDO UNIVERSITY
Sapporo-shi
JP
|
Family ID: |
37307669 |
Appl. No.: |
11/919217 |
Filed: |
April 28, 2005 |
PCT Filed: |
April 28, 2005 |
PCT NO: |
PCT/JP2005/008163 |
371 Date: |
October 25, 2007 |
Current U.S.
Class: |
131/339 |
Current CPC
Class: |
A24D 3/10 20130101; A24D
3/14 20130101 |
Class at
Publication: |
131/339 |
International
Class: |
A24D 3/04 20060101
A24D003/04 |
Claims
1. A cigarette filer comprising: a filter fiber bundle through
which smoke of a cigarette passes; cellulose beads mixed into the
filter fiber bundle to be scattered therein, and double-stranded
DNA molecules adhered to an outer surface of the cellulose beads,
wherein harmful substances such as benzo[a]pyrene contained in the
smoke of the cigarette are trapped by intercalation with the
double-stranded DNA molecules so as to be removed.
2. The cigarette filter according to claim 1, wherein mean particle
size of the cellulose beads is in a range from 50 to 2000
.mu.m.
3. The cigarette filter according to claim 1, wherein a mean
particle size of the cellulose beads is in a range from 300 to 800
.mu.m.
4. The cigarette filter according to claim 1, wherein the cellulose
beads are present in a range from 1 to 50% by weight and the
double-stranded DNA molecules are present in a range from 0.01 to
10% by weight based on the weight of the filter fiber bundle.
5. The cigarette filter according to claim 1, wherein the filter
fiber bundle is a filter fiber bundle formed of cellulose
acetate.
6. A paper wrapped cigarette provided with the cigarette filter
according to claim 4.
7. The cigarette filter according to claim 2, wherein the cellulose
beads are present in a range from 1 to 50% by weight and the
double-stranded DNA molecules are present in a range from 0.01 to
10% by weight based on the weight of the filter fiber bundle.
8. The cigarette filter according to claim 3, wherein the cellulose
beads are present in a range from 1 to 50% by weight and the
double-stranded DNA molecules are present in a range from 0.01 to
10% by weight based on the weight of the filter fiber bundle.
9. The cigarette filter according to claim 2, wherein the filter
fiber bundle is a filter fiber bundle formed of cellulose
acetate.
10. The cigarette filter according to claim 3, wherein the filter
fiber bundle is a filter fiber bundle formed of cellulose
acetate.
11. The cigarette filter according to claim 4, wherein the filter
fiber bundle is a filter fiber bundle formed of cellulose
acetate.
12. The cigarette filter according to claim 7, wherein the filter
fiber bundle is a filter fiber bundle formed of cellulose
acetate.
13. The cigarette filter according to claim 8, wherein the filter
fiber bundle is a filter fiber bundle formed of cellulose
acetate.
14. A paper wrapped cigarette provided with the cigarette filter
according to claim 7.
15. A paper wrapped cigarette provided with the cigarette filter
according to claim 8.
16. A paper wrapped cigarette provided with the cigarette filter
according to claim 5.
17. A paper wrapped cigarette provided with the cigarette filter
according to claim 9.
18. A paper wrapped cigarette provided with the cigarette filter
according to claim 10.
19. A paper wrapped cigarette provided with the cigarette filter
according to claim 11.
20. A paper wrapped cigarette provided with the cigarette filter
according to claim 12.
21. A paper wrapped cigarette provided with the cigarette filter
according to claim 13.
Description
TECHNICAL FIELD
[0001] The present invention relates to a cigarette filter, and
more particularly, to a cigarette filter capable of more
effectively removing harmful substances in cigarette smoke such as
pyrene while slightly impairing flavor of its own and air
permeability of the filter during smoking.
BACKGROUND ART
[0002] A filter in a paper-wrapped cigarette has been developed to
remove the tarry substance or tar of the cigarette in consideration
with the influence of smoking cigarette to the human health.
Recently, health problems caused by smoking have been increasingly
focused, and the demand for filters capable of removing the harmful
substances in cigarette smoke such as pyrene has been increased.
Patent Document 1 proposes a cigarette filter to which DNA serving
as an active constituent is directly adhered so as to trap
carcinogenic and toxic components in cigarette smoke. Patent
Document 2 proposes art in which UV ray is irradiated so as to fix
DNA to the support such as the cigarette filter.
[0003] Patent Document 1; French Patent No. 2798302
[0004] Patent Document 2: JP-A 2001-81098
DISCLOSURE OF THE INVENTION
Problems to be Solved by the Invention
[0005] The cigarette filter capable of removing a harmful substance
is required not only to remove the harmful substance in cigarette
smoke as much as possible but also not to impair the distinctive
flavor of the cigarette, that is, to allow smooth passage of a
chemical substance which serves as the sour of the flavor and
further to keep the good air permeabilities. If the chemical
substance as the source of the flavor is removed, the smoker my
feel it as tasteless. If the air permeability of the filter is
impaired, the smoker may feel uncomfortable in inhaling cigarette
smoke, which may hurt the commercial value of the cigarette.
[0006] The cigarette filter disclosed in Patent Document 1 has been
developed with no consideration for maintaining the flavor of the
cigarette, and air permeability during smoking. Meanwhile, Patent
Document 2 describes the art in which the filter with the DNA is
used as the cigarette filter, but does not clarify the level of the
effect for removing the harmful substance, the flavor of the
cigarette, and the air permeability of the filter. Thus, the filter
has not been applied to the practical use as the cigarette filter
yet.
Means for Solving the Problem
[0007] The inventor has been dedicated to develop a cigarette
filter that is capable of more effectively removing the harmful
substances in cigarette smoke such as pyrenes, as well as prevents
impairment in the distinct flavor of the cigarette and in the air
permeability of the filter during smoking. In the course of the
development of such cigarette filter, the inventor selected the
double-stranded DNA suitable as a substance for absorbing more
amount of harmful substances such as pyrenes while absorbing less
amount of substances such as nicotine and tasty constituents which
constitute the source of the flavor of the cigarette. Considering
the fact that the air permeability of the filter is likely to be
impaired when the double-stranded DNA molecules are distributed in
the entire filter fiber bundle so as to be adhered thereto,
especially when a large amount of the double-stranded DNA molecules
are distributed, the inventor studied various ways of scattering
the double-stranded DNA in the filter fiber bundle partially rather
than entirely. Then the double-stranded DNA is adhered to fine
powder of the cellulose bead such that the fine powder of the
cellulose bead to which the double-stranded DNA has been adhered is
scattered in the filter fiber bundle. As a result, the harmful
substance was effectively removed, and the substance that is the
source of the distinct flavor of the cigarette smoothly passed
through the filter while suppressing impairment in the air
permeability of the filter. It is confirmed that more
double-stranded DNA was adhered to the outer surface of the fine
powder of the cellulose bead.
[0008] The present invention has been made in view of the
aforementioned background to provide a cigarette filter that is
capable of effectively removing harmful substances in cigarette
smoke such as pyrenes and that suppresses impairment both in the
distinct flavor of the cigarette and in the air permeability of the
filter during smoking, by adhering the double-stranded DNA to the
fine powder with large surface area, such as the cellulose bead, so
as to mix the double-stranded DNA adhered to the fine powder into
the filter fiber bundle.
[0009] According to an aspect of the present invention, a cigarette
filter includes a filter fiber bundle through which cigarette smoke
passes, fine powders with high specific surface area mixed into the
filter fiber bundle to be scattered therein, and a double-stranded
DNA molecule adhered to an outer surface of the fine powder with
high specific surface area. In the cigarette filter, harmful
substances such as benzo[a]pyrene are trapped by intercalation with
the double-stranded DNA particle so as to be removed.
[0010] According to a preferable aspect of the present invention,
the fine powder with high specific surface area is formed of the
cellulose bead.
[0011] Preferably, the mean particle size of the fine powder with
high specific surface area is in a range from 50 to 2000 .mu.m, and
more preferably, from 300 to 800 .mu.m.
[0012] In the present invention, the cigarette filter contains the
fine powder with high specific surface area in the range from 1 to
50% by weight, and the double-stranded DNA particle in the range
from 0.01 to 10% by weight, based on the weight of the filter fiber
bundle.
[0013] Still another aspect of the present invention relates to a
paper-wrapped cigarette provided with the aforementioned cigarette
filter.
EFFECTS OF THE INVENTION
[0014] The cigarette filter according to the present invention
includes the filter fiber bundle through which cigarette smoke
passes, the fine powder with high specific surface area mixed in
the filter fiber bundle, which allows the double-stranded DNA to be
adhered to the outer surface, and the double-stranded DNA molecule
adhered to the outer surface of the fine powder with high specific
surface area. In the structure described above, it is possible to
secure sufficient air permeability of cigarette smoke as well as to
suppress absorption and removal of the tasty constituent contained
in the smoke, such as tar, so as to maintain smoking feel. The
harmful substances such as benzo[a]pyrene may be trapped by
intercalation between the double-stranded DNA molecules effectively
so as to be removed. As the double-stranded DNA molecule is adhered
to the fine powder with high specific surface area so as to become
unlikely to be desorbed compared to the case of direct adhesion to
the cigarette filter. As a result, the effect of removing the
harmful substance may be maintained for an extended period of
time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a view of an electron micrograph showing fine
powder with high specific surface area used in the present
invention;
[0016] FIG. 2 is a view of an electron micrograph of the fine
powder with high specific surface area to which the double-stranded
DNA has been adhered in the present invention;
[0017] FIG. 3 is another view of an electron micrograph of the fine
powder with high specific surface area to which the double-stranded
DNA has been adhered in the present invention;
[0018] FIG. 4A is an explanatory view showing a longitudinal
section of the cigarette filter according to the present invention;
and
[0019] FIG. 4B is an explanatory view showing a longitudinal
section of a cigarette filter having the double-stranded DNA
directly adhered to the filter fiber bundle.
BEST MODES FOR CARRYING OUT THE INVENTION
[0020] In the present invention, fine powder 2 with high specific
surface area having a unique structure with plural gaps 1 formed in
the outer surface as shown in FIG. 1 is used for the purpose of
adhering more double-stranded DNA in a concentrated manner. A
double-stranded DNA 3 is adhered to the outer surface of the fine
powder 2 with high specific surface area (see FIGS. 2 and 3). Any
type of the fine powder 2 with high specific surface area may be
employed so long as it allows the double-stranded DNA molecules to
be adhered thereto. The fold, swindle, or twist may be formed
instead of the gap. The fine powder with high specific surface area
according to the present invention may be formed to have the
aforementioned gap, fold, wrinkle, or twist not only in the outer
surface but also inside. The fine powder with high specific surface
area may be arbitrarily configured, for example, the porous
configuration.
[0021] The cigarette filter according to the present invention, in
which the fine powder with high specific surface area holding more
double-stranded DNA molecules is mixed and scattered, is much more
advantageous compared to the generally employed cigarette filter
having the DNA directly held in the filter in view of the
performance for effectively maintaining the air permeability of the
filter. The aforementioned advantage will be described below, in
comparison with the generally employed cigarette filter in which
the double-stranded DNA molecules are directly adhered to the
filter fiber bundle.
[0022] Referring to FIG. 4A, the double-stranded DNA 3 is adhered
to the outer surface of the fine powder with high specific surface
area with the aforementioned structure. A cigarette filter 5 is
formed by making into and scattering in a filter fiber bundle 4,
the fins powder 2 with high specific surface area, to which the
double-stranded DNA 3 has been adhered. In order to distribute a
predetermined amount of the double-stranded DNA 3 in a filter fiber
bundle 4, the fine powder 2 with high specific surface area holding
the double-stranded DNA 3 is required to be mixed into the filter
fiber bundle 4 while being scattered. As a result the particles of
the fine powder 2 with high specific surface area to which the
double-stranded DNA 3 is adhered are apart from one another to
ensure to form the sufficient passage for cigarette smoke 6.
[0023] Meanwhile, referring to FIG. 4B, in a cigarette filter 7 in
which the double-sided DNA 3 is directly adhered to the filter
fiber bundle 4 (for example, the filter fiber bundle is impregnated
in water solution of DNA, and then dried to hold the DNA), the
double-stranded DNA 3 is substantially uniformly distributed all
over the filter fiber bundle 4 for the purpose of distributing the
same amount of the double-stranded DNA thereon. Consequently the
respective molecules of the double stranded DNA 3 are positioned
adjacent with one another. The resultant narrow passage of the
cigarette smoke 6 impairs air permeability of the filter.
[0024] The cigarette filter according to the present invention is
designed to effectively maintain the air permeability of the
filter.
[0025] Preferably, the mean particle size of the fine powder with
high specific surface area according to the present invention is in
the range from 50 to 2000 .mu.m for the purpose of preventing
clogging of the filter fiber bundle. More preferably, the mean
particle size is in the range from 300 to 800 .mu.m. The fine
powder with high specific surface area is not particularly limited
in terms of material and shape so long as it is pervious with
respect to the cigarette smoke, and is structured to have a large
specific surface area so as to allow adhesion of the
double-stranded DNA molecules to the outer surface. For example,
the fine powder with high specific surface area may be formed of a
synthetic or natural polymer such as polystyrene, polyvinyl
alcohol, polyvinyl chloride, polyethylene, cellulose, starch,
natural rubber, gelatin, chitin, chitosan, and acetate, an
inorganic substance such as silica, alumina, activated carbon, and
diatom, and a mixture thereof. Preferably, the fine powder with
high specific surface area is formed of the cellulose polymer,
especially, cellulose acetate, for example. Preferably, the fine
powder with high specific surface area has a bead-like form, and
the most preferably, the cellulose bead form. It is sufficient to
allow the fine powder with high specific surface area to be simply
mixed in the filter fiber bundle. The double-stranded DNA molecules
may be adhered to the fine powder with high specific surface area
under the physical force such as intermolecular force and
electrostatic force, through the chemical bonding such as covalent
bonding, ion bonding and coordinate bonding, or combination of the
physical forces aid the chemical bondings. In the present
invention, the state where the double-stranded DNA molecules exist
on the fine powder with high specific surface area so as not to be
desorbed therefrom may be considered as being adhered to the fine
powder with high specific surface area.
[0026] Meanwhile, the double-stranded DNA employed in the present
invention is formed of two polynucleotide chains (double helix)
with the helical form. It is preferable to use the DNA derived from
the milt (testis) of fish such as salmon, herring and codfish, or
the double-stranded DNA derived from the thymus of mammal or birds
such as cattle, hog, and chicken. In the double-stranded DNA,
planar bases each having the structural complementation protrude
from the sugar-phosphate frameworks of two polynucleotide chains
toward the center of the helix perpendicularly to the axis thereof,
and the bases are hydrogen bonded. In case of type B structure, a
gap approximately 1.1 nm wide and 0.34 nm high is formed between
the base pairs of the duplex, and so the gap is able to accommodate
the small molecules with the planar structure. The above-described
phenomenon is referred to as the intercalation which may be
accelerated by the charge and hydrophobicity of the small
molecules. As most of the substances harmful to the human health,
such as dioxins are formed of plural benzene rings, and has the
planar structure, the use of the double-stranded DNA is more
effective for removing the harmful substance in cigarette smoke.
The structure of the double-stranded DNA employed in the present
invention is not particularly limited so long as it is capable of
adhering to the outer surface of the fine powder with high specific
surface area. Conceivable forms of the double-stranded DNA may
include powder, fiber, and film, and the fine powder form is
particularly preferable. The use of the fine powder as the
double-stranded DNA allows it surface area to be larger with the
same amount, thereby further improving the effect of
absorbing/removing the harmful substance.
[0027] In view of the efficiency for removing the harmful
substance, the respective contents of the fine powder with high
specific surface area and the double-stranded DNA particles may be
in the ranges from 1 to 50% by weight, and 0.01 to 10% by weight
with respect to the filter fiber bundle, respectively.
[0028] The cigarette filter according to the present invention may
further include an activated carbon, a substance other than Me
double-stranded DNA capable of removing the harmful substance, an
aroma chemical, or the like.
EXAMPLES
[0029] An example of the present invention will be described in
detail, however, the present invention is not limited to the
following explanation.
Example 1
[0030] A cigarette filter 5 having the structure as shown in FIG.
4A according to the present invention and a cigarette A provided
with the cigarette filter 5 are produced as described below.
[0031] Firstly, 750 mg of the double-stranded DNA in the form of
fine powder was applied to be adhered to approximately 100 g of the
cellulose beads (mean particle size: 300 to 800 .mu.m) as the fine
powder with high specific surface area. Then 0.1 g of the cellulose
beads to which the double-stranded DNA was adhered (content of the
double-stranded DNA: 0.75 mg) was mixed into the filter fiber
bundle formed of cellulose acetate (weight: approximately 1.0 g)
using a cigarette filter manufacturing machine. Thereafter, by the
use of the cigarette filter manufacturing machine, the mixture was
wrapped with rice paper so as to be formed into a round-bar like
shape, and thus the cigarette filter according to the present
invention was obtained. The filter of Research Cigarette 2R4F
(trade name, University of Kentucky, United States) was removed to
be replaced by the above-obtained cigarette filter according to the
present invention to produce the cigarette A.
Comparative Example 1
[0032] The filter of Research Cigarette 2R4F (trade name,
University of Kentucky, United States) was removed to be replaced
by the filter (no double-stranded DNA nor the cellulose beads
holding the double-stranded DNA) formed of the filter fiber bundle
used in Example 1 to produce a cigarette B.
Comparative Example 2
[0033] Approximately 1.0 g of the filter fiber bundle used for
producing the cigarette B was impregnated in water solution
containing the double stranded DNA of 5% by weight. Then the filter
fiber bundle was taken out from the water solution of the
double-stranded DNA, and sufficiently dried at approximately
37.degree. C. The ultraviolet ray with the wavelength of 260 nm was
irradiated to the fiber bundle to form the cigarette filter. The
double-stranded DNA adhered to the cigarette filter measured
approximately 1 mg. The thus obtained cigarette filter was wrapped
with rice paper using the cigarette filter manufacturing machine so
as to be formed into a round-bar like shape. The filter of the
Research Cigarette 2R4F (trade name, University of Kentucky, United
States) was removed to be replaced by the cigarette filter having
the round-bar like shape to produce a cigarette C.
Comparative Example 3
[0034] The water solution containing the double-stranded DNA of 5%
by weight was sprayed to approximately 1.0 g of the filter fiber
bundle used for producing the cigarette B, and sufficiently dried
at 37.degree. C. to produce the cigarette filter. The
double-stranded DNA adhered to the cigarette filter measured
approximately 1 mg. The thus obtained cigarette filler was wrapped
with rice paper using the cigarette filter manufacturing machine so
as to be formed into a round-bar like shape. The filter of the
Research Cigarette 2R4F (trade name, University of Kentucky, United
States) was removed to be replaced by the cigarette filter having
the round-bar like shape to produce a cigarette D.
Comparative Example 4
[0035] Approximately 1.0 g of the filter fiber bundle used for
producing the cigarette B was impregnated in the water solution
that contains 5% by weight of the double-stranded DNA and 0.1% by
weight of NaF for about 1 minute. Then the filter was taken out
from the water solution of the DNA, and sufficiently dried at
approximately 37.degree. C. to produce the cigarette filter. The
DNA adhered to the cigarette filter measured approximately 3 mg.
The thus obtained cigarette filter was wrapped with rice paper
using the cigarette filter manufacturing machine so as to be formed
into a round-bar like shape. The filter of Research Cigarette 2R4F
(bade name, University of Kentucky, United States) was removed to
be replaced by the above-obtained cigarette filter having the
round-bar like shape to produce a cigarette E.
Test Example 1
[0036] Experiment with respect to each effect for removing the
benzo[a]pyrene generated by smoking the receptive cigarettes A, B,
C, D and E was implemented.
(Test Procedure)
[0037] A Hamburg II automatic smoking machine was allowed to take
the mainstream smoke (air: cigarette smoke=7:3) 10 times under the
condition where 1 puff/35 ml per two seconds of 20 cigars per day
with respect to the above-produced cigarettes A, B, C, D and E. The
amount of the benzo[a]pyrene contained in the total air discharged
outside after smoking was measured. The measurement results are
shown in Table 1.
[Table 1]
TABLE-US-00001 [0038] TABLE 1 Outflow amount of benzo[a]pyrene
(ng/UNK) A 0.15 B 0.45 C 0.25 D 0.31 E 0.41
(Results)
[0039] From the results shown in Table 1, compared to each outflow
amount of benzo[a]pyrene discharged outside after smoking of the
cigarettes B, C, D and E, that is, 0.45 ng/UNK, 0.25 ng/UNK, 0.31
ng/UNK, and 0.41 ng/UNK, the outflow amount in case of smoking the
cigarette A provided with the cigarette filter according to the
present invention measured only 0.15 ng/UNK. Although the cigarette
A contains only 0.75 mg of the double-stranded DNA, the effect for
removing the benzo[a]pyrene was higher than those of the cigarettes
C, D and E each holding the double-stranded DNA of 1 mg, 1 mg, and
3 mg, respectively. In other words, the cigarette A produced by
mixing the cellulose beads holding the double-stranded DNA into the
fiber bundle exhibits the higher effect for removing the
benzo[a]pyrene than those of the cigarettes C and D produced by
directly adhering the double-stranded DNA to the fiber bundle
through impregnating in the water solution or spray. The cigarette
filter according to the present invention which holds a large
amount of the double-stranded DNA on the cellulose beads to be
mixed into the fiber bundle provides flintier excellent effect for
absorbing/removing the pyrenes such as the benzo[a]pyrene.
Test Example 2
[0040] The test was performed with respect to the smoking feel
level derived from smoking the cigarettes A, B, C, D and E produced
as Example 1 and Comparative Examples 1 to 4.
Test Procedure:
[0041] In the test, 30 subjects smoked the cigarettes A, B, C, D
and E such that the comparison with respect to the flavor and smoke
inhaling feel was made between the cigarettes A, C, D, E each
holding the double-stranded DNA and the cigarette B holding no
double-stranded DNA. The evaluation was performed based on
impairment level in the flavor and in the smoke inhaling feel
resulting from smoking of the cigarettes A, C, D, and E in
reference to the cigarette B. If the subjects determined that the
flavor and smoke inhaling feel derived from smoking the cigarette
A, C, D or E hardly changed or they did not notice such change, a
score of 3 points was given. If they slightly felt discomfort
during smoking, a score of 2 points was given. If they clearly felt
discomfort during smoking, a score of 1 point was given. Each
average score of the cigarettes A, B, C, D and E was calculated,
and the rats are shown in Table 2
[Table 2]
TABLE-US-00002 [0042] TABLE 2 Flavor Smoke inhaling level A 2.7 2.8
B 2.7 2.8 C 2.2 2.3 D 2.1 2.2 E 2.1 2.2
[0043] The test results of the cigarette A with the cigarette
filter according to the present invention holding the
double-stranded DNA with respect to the ease of smoke inhaling and
the flavor are substantially the same as those of the cigarette B
provided with the cigarette filter having no double-stranded DNA.
It also becomes clear that the cigarettes C, D and E each having
the double-stranded DNA directly adhered to the filter fiber bundle
could suppress impairment in the smoke inhaling feel less compared
to the cigarette A. The aforementioned effect is assumed to be
obtained due to the form of the cigarette filter, in which the
double-stranded DNA is adhered to the fine powder with high
specific surface area such as the cellulose beads in the
concentrated manner rather than the direct adhesion such that the
particles of fine powder with high specific surface area are
scattered in the filter fiber bundle of the cigarette at sufficient
intervals with one another.
* * * * *