U.S. patent application number 17/469773 was filed with the patent office on 2022-01-20 for self-assembled active agents.
The applicant listed for this patent is Method Products, PBC, The United States of America, as represented by the Secretary of Agriculture, The United States of America, as represented by the Secretary of Agriculture. Invention is credited to DIANA M. FRANQUIVILLANUEVA, WILLIAM M. HART-COOPER, KAJ JOHNSON, LAUREN E. LYNN, WILLIAM J. ORTS.
Application Number | 20220015367 17/469773 |
Document ID | / |
Family ID | 1000005871892 |
Filed Date | 2022-01-20 |
United States Patent
Application |
20220015367 |
Kind Code |
A1 |
HART-COOPER; WILLIAM M. ; et
al. |
January 20, 2022 |
SELF-ASSEMBLED ACTIVE AGENTS
Abstract
A self-assembled active agent may be formed by a process
including covalently bonding at least a first component molecule
and a second component molecule, the two component molecules
displaying synergy such that the effective amount of the
self-assembled active agent is lower than the sum of the effective
amounts of the first component molecule and the second component
molecule. The component molecules may be chosen such that the
covalent bonding is reversible, for example through a hydrazone
bond between an amine and an aldehyde. The active agent may thus
have controllable activity such as an antimicrobial agent, a
biocide, an antiviral agent, a preservative, an antifouling agent,
a disinfectant, or a sensor agent, such as for a particular
molecule or for pH.
Inventors: |
HART-COOPER; WILLIAM M.;
(RICHMOND, CA) ; ORTS; WILLIAM J.; (BURLINGAME,
CA) ; JOHNSON; KAJ; (SAUSALITO, CA) ; LYNN;
LAUREN E.; (GLEN GARDNER, NJ) ; FRANQUIVILLANUEVA;
DIANA M.; (CONCORD, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
The United States of America, as represented by the Secretary of
Agriculture
Method Products, PBC |
Washington
San Francisco |
DC
CA |
US
US |
|
|
Family ID: |
1000005871892 |
Appl. No.: |
17/469773 |
Filed: |
September 8, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15909421 |
Mar 1, 2018 |
11166464 |
|
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17469773 |
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62467324 |
Mar 6, 2017 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A01N 49/00 20130101;
A01N 55/08 20130101; C07C 281/18 20130101; A01N 31/00 20130101;
A01N 2300/00 20130101; A01N 47/44 20130101; C07C 281/16 20130101;
C07C 279/18 20130101 |
International
Class: |
A01N 47/44 20060101
A01N047/44; C07C 279/18 20060101 C07C279/18; A01N 49/00 20060101
A01N049/00; A01N 55/08 20060101 A01N055/08; C07C 281/18 20060101
C07C281/18; C07C 281/16 20060101 C07C281/16 |
Claims
1. A method of treating for a pathogen or microbe, the method
comprising applying an effective amount of an active agent to a
designated area or object, wherein the active agent is a compound
of the formula: ##STR00027## wherein R.sub.1 and R.sub.3 are,
independently, optionally substituted one or more times, wherein in
the case of either of R.sub.1 or R.sub.3 having at least one
substitution, a first substitution is one of an alcohol group, an
aldehyde group, a 5-member ring, a 6-member ring, a halide, a
halide-diol, an ether, and a straight or branched, saturated or
unsaturated aliphatic group, wherein n is at least 2, and wherein
R.sub.1 is one of the following: ##STR00028## ##STR00029## wherein
R.sub.2 is: ##STR00030## and wherein R.sub.3 is one of:
##STR00031## ##STR00032##
2. The method of treating for a pathogen or microbe of claim 1,
wherein the active agent is one of: ##STR00033## ##STR00034##
##STR00035## ##STR00036## ##STR00037## ##STR00038## ##STR00039##
##STR00040## ##STR00041## ##STR00042## ##STR00043## and an analog
thereof.
3. An active agent, wherein the active agent is formed by a process
comprising covalently bonding at least a first component molecule
and a second component molecule, wherein an effective amount of the
active agent is lower than the sum of an effective amount of the
first component molecule when used individually and an effective
amount of the second component molecule when used individually,
wherein the first component molecule is an amine and the second
component molecule is one of an aldehyde and a ketone, and wherein
the covalent bonding between the first component molecule and the
second component molecule includes the formation of a hydrazone
bond.
4. The active agent of claim 3, wherein the active agent is formed
by self-assembly of the first component molecule and the second
component molecule.
5. The active agent of claim 3, wherein the first component
molecule has two or more amine functional groups.
6. The active agent of claim 3, wherein the first component
molecule is 1,3-diaminoguanidine or aminoguanidine.
7. The active agent of claim 3, wherein the second component
molecule has two or more aldehyde functional groups.
8. The active agent of claim 3, wherein the second component
molecule has the following chemical structure: ##STR00044## wherein
R.sup.1 is --CHCO, and wherein R.sup.2, R.sup.3, R.sup.4, R.sup.5,
and R.sup.6 are, independently, one of H, --CHCO, a saturated or
unsaturated branched or unbranched aliphatic, a halide, a
halide-diol, or --OH.
9. The active agent of claim 8, wherein at least one of R.sup.3,
R.sup.4, and R.sup.5 is --CHCO.
10. The active agent of claim 9, wherein R.sup.3 and R.sup.5 are
both --CHCO.
11. The active agent of claim 3, wherein the second component is
one of glyoxal, glutaraldehyde, benzylaldehyde, phthalaldehyde,
terephthalaldehyde, isophthalaldehyde,
benzene-1,3,5-tricarboxaldehyde, 2-bromoisophthalaldehyde,
4-tBu-2,6-diformylphenol, 4-Me-2,6-diformylphenol,
3,5-diformyl-2-propoxyphenylboronic acid, 2,5-thiophenedialdehyde,
and 2,5-furandialdehyde.
12. A method of killing a microbe, the method comprising: treating
a growth of the microbe with an effective amount of an active
agent, an effective amount of the active agent being achieved by
adding a combination of a pre-determined amount of a first
component molecule and a pre-determined amount of a second
component molecule, wherein the first component molecule and the
second component molecule are capable of self-assembly via the
formation of a hydrazone covalent bond.
13. The method of killing a microbe of claim 12, wherein the first
component molecule is 1,3-diaminoguanidine or aminoguanidine.
14. The method of killing a microbe of claim 12, wherein the second
component molecule has two or more aldehyde functional groups.
15. The method of killing a microbe of claim 12, wherein the second
component molecule has the following chemical structure:
##STR00045## wherein R.sup.1 is --CHCO, and wherein R.sup.2,
R.sup.3, R.sup.4, R.sup.5, and R.sup.6 are, independently, one of
H, --CHCO, a saturated or unsaturated branched or unbranched
aliphatic, a halide, a halide-diol, or --OH.
16. The method of killing a microbe of claim 15, wherein at least
one of R.sup.3, R.sup.4, and R.sup.5 is --CHCO.
17. The method of killing a microbe of claim 16, wherein R.sup.3
and R.sup.5 are both --CHCO.
18. A method of producing a self-assembled active agent, the method
comprising combining a first component with a second component in a
solution, wherein the first component is a molecule with an amine
functional group and the second component is a molecule with an
aldehyde or a ketone functional group, wherein the first component,
the second component, and the combination of the first component
and the second component each has a bioactivity, and wherein the
bioactivity of the combination of the first component and the
second component is greater than the sum of the bioactivity of the
first component and the bioactivity of the second component.
19. The method of producing a self-assembled active agent of claim
18, wherein the first component and the second molecule are capable
of self-assembly via the formation of a hydrazone covalent
bond.
20. The method of producing a self-assembled active agent of claim
18, wherein the first component has two or more amine functional
groups.
21. The method of producing a self-assembled active agent of claim
18, wherein the second component has two or more aldehyde
functional groups.
22. The method of producing a self-assembled active agent of claim
18, wherein the second component molecule has the following
chemical structure: ##STR00046## wherein R.sup.1 is --CHCO, and
wherein R.sup.2, R.sup.3, R.sup.4, R.sup.5, and R.sup.6 are,
independently, one of H, --CHCO, a saturated or unsaturated
branched or unbranched aliphatic, a halide, a halide-diol, or
--OH.
23. The method of producing a self-assembled active agent of claim
22, wherein at least one of R.sup.3, R.sup.4, and R.sup.5 is
--CHCO.
24. The method of producing a self-assembled active agent of claim
23, wherein R.sup.3 and R.sup.5 are both --CHCO.
25. A composition comprising at least one compound of the formula
##STR00047## wherein R.sup.1 and R.sup.2 independently are (1)
hydrogen (--H), or (2) an aliphatic functional group that may be
substituted with additional aliphatic groups, --OH groups, ethers,
esters, acids, thiols, thioesters, halogens, or a 1-2 ring
heterocycle that contains O, N and/or S as the heteroatom, or (3)
an aromatic functional group wherein one or more --H is substituted
with an alkyl, aliphatic groups, OH groups, ethers, esters, acids,
amines, ammoniums, alcohols, thiols, thioesters, halogens, or a 1-2
ring heterocycle that contains O, N and/or S as the heteroatom,
R.sup.3, R.sup.4 and R.sup.5 independently are aliphatic functional
group that may be substituted with additional aliphatic groups,
--OH groups, ethers, esters, acids, amines, ammoniums, alcohols,
thiols, thioesters or halogens.
26. The composition of claim 25, wherein the compound is an active
agent.
27. The composition of claim 26, wherein the active agent is formed
by self-assembly of a first component molecule and a second
component molecule.
28. The composition of claim 26, wherein the active agent has
antimicrobial activity.
29. The composition of claim 25, wherein said compound is a
compound in FIG. 10 or FIG. 11.
30. A method for killing microorganisms on or in an object or area,
said method comprising contacting said object or area with an
effective microorganisms killing amount of a composition comprising
at least one compound of claim 25.
31. The method of claim 49, wherein said compound is a compound in
FIG. 10 or FIG. 11.
32. An active agent, wherein the active agent is formed by a
process comprising covalently bonding at least a first component
molecule and a second component molecule, and wherein an effective
amount of the active agent is lower than the sum of an effective
amount of the first component molecule when used individually and
an effective amount of the second component molecule when used
individually; wherein said active agent is a compound of claim
25.
33. The active agent of claim 32, wherein the active agent is
formed by self-assembly of the first component molecule and the
second component molecule.
34. The active agent of claim 32, wherein the first component
molecule is an amine and the second component molecule is an
aldehyde.
35. The active agent of claim 32, wherein the first component
molecule is an amine and the second component molecule is a
ketone.
36. The active agent of claim 32, wherein the covalent bonding
between the first component molecule and the second component
molecule includes the formation of a hydrazone bond.
37. The active agent of claim 32, wherein the first component
molecule is 1,3-diaminoguanidine or aminoguanidine.
38. The active agent of claim 32, wherein the second component
molecule has the following chemical structure: ##STR00048## wherein
R.sup.1 and R.sup.2 independently are (1) hydrogen (--H), or (2) an
aliphatic functional group that may be substituted with additional
aliphatic groups, --OH groups, ethers, esters, acids, thiols,
thioesters, halogens, or a 1-2 ring heterocycle that contains O, N
and/or S as the heteroatom, or (3) an aromatic functional group
wherein one or more --H is substituted with an alkyl, aliphatic
groups, OH groups, ethers, esters, acids, amines, ammoniums,
alcohols, thiols, thioesters, halogens, or a 1-2 ring heterocycle
that contains O, N and/or S as the heteroatom, and R.sup.3, R.sup.4
and R.sup.5 independently are aliphatic functional group that may
be substituted with additional aliphatic groups, --OH groups,
ethers, esters, acids, amines, ammoniums, alcohols, thiols,
thioesters or halogens.
39. The active agent of claim 32, wherein said active agent is a
compound in FIG. 10 or FIG. 11.
40. A method of killing a microbe on or in an object or area, said
method comprising contacting said object or area with an effective
microorganisms killing amount of a self-assembled active agent, an
effective amount of the active agent being achieved by adding a
combination of a pre-determined amount of a first component
molecule and a pre-determined amount of a second component
molecule, wherein the first component molecule and the second
component molecule are capable of self-assembly via the formation
of a hydrazone covalent bond.
41. The method of killing a microbe of claim 40, wherein the first
component molecule is an amine and the second component molecule is
one of an aldehyde and a ketone.
42. The method of killing a microbe of claim 40, wherein the first
component molecule is 1,3-diaminoguanidine or aminoguanidine.
43. The method of killing a microbe of claim 40, wherein the second
component molecule has the following chemical structure:
##STR00049## wherein R.sup.1 and R.sup.2 independently are (1)
hydrogen (--H), or (2) an aliphatic functional group that may be
substituted with additional aliphatic groups, --OH groups, ethers,
esters, acids, thiols, thioesters, halogens, or a 1-2 ring
heterocycle that contains O, N and/or S as the heteroatom, or (3)
an aromatic functional group wherein one or more --H is substituted
with an alkyl, aliphatic groups, OH groups, ethers, esters, acids,
amines, ammoniums, alcohols, thiols, thioesters, halogens, or a 1-2
ring heterocycle that contains O, N and/or S as the heteroatom, and
R.sup.3, R.sup.4 and R.sup.5 independently are aliphatic functional
group that may be substituted with additional aliphatic groups,
--OH groups, ethers, esters, acids, amines, ammoniums, alcohols,
thiols, thioesters or halogens.
44. The method of killing a microbe of claim 40, wherein said
active agent is a compound in FIG. 10 or FIG. 11.
45. A method of producing a self-assembled active agent, the method
comprising combining a first component with a second component in a
solution, wherein the first component is a molecule with an amine
functional group and the second component is a molecule with an
aldehyde or a ketone functional group, wherein the first component,
the second component, and the combination of the first component
and the second component each has a bioactivity, and wherein the
bioactivity of the combination of the first component and the
second component is greater than the sum of the bioactivity of the
first component and the bioactivity of the second component.
46. The method of producing a self-assembled active agent of claim
45, wherein the first component and the second molecule are capable
of self-assembly via the formation of a hydrazone covalent
bond.
47. The method of producing a self-assembled active agent of claim
45, wherein the first component is 1,3-diaminoguanidine or
aminoguanidine.
48. The method of producing a self-assembled active agent of claim
45, wherein the second component molecule has the following
chemical structure: ##STR00050## wherein R.sup.1 and R.sup.2
independently are (1) hydrogen (--H), or (2) an aliphatic
functional group that may be substituted with additional aliphatic
groups, --OH groups, ethers, esters, acids, thiols, thioesters,
halogens, or a 1-2 ring heterocycle that contains O, N and/or S as
the heteroatom, or (3) an aromatic functional group wherein one or
more --H is substituted with an alkyl, aliphatic groups, OH groups,
ethers, esters, acids, amines, ammoniums, alcohols, thiols,
thioesters, halogens, or a 1-2 ring heterocycle that contains O, N
and/or S as the heteroatom, and R.sup.3, R.sup.4 and R.sup.5
independently are aliphatic functional group that may be
substituted with additional aliphatic groups, --OH groups, ethers,
esters, acids, amines, ammoniums, alcohols, thiols, thioesters or
halogens.
49. The method of producing a self-assembled active agent of claim
45, wherein said self-assembled active agent is a compound in FIG.
10 or FIG. 11.
Description
REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. patent application
Ser. No. 15/909,421, filed Mar. 1, 2018, which itself claims
priority from Provisional Patent Application No. 62/467,324, filed
on Mar. 6, 2017, the contents of both of which are incorporated
herein by reference in their entireties.
BACKGROUND OF THE INVENTION
[0002] Chemical antimicrobial agents such as antibiotics,
antiseptics, disinfectants and preservatives are essential for
modern medicine, agriculture and other industries. Despite this
importance, chemical antimicrobial agents often exhibit significant
toxicity to non-microbial organisms, thereby causing collateral
damage to ecosystems and also accelerating the evolution of
antimicrobial resistance. The latter two problems may result from a
substance's persistence in the environment. The longer a substance
persists in the environment, the greater the potential for
bioaccumulation and microbial exposure at sub-inhibitory
concentrations, the latter of which enables the evolution of
antimicrobial resistance. This effect is cause for concern; some
estimates predict mortalities from antibiotic resistant infections
may surpass those from cancer within several decades. Given the
growing hazard of antimicrobial resistance and the damage to the
environment caused by persistent chemicals, the development of
antimicrobials that are short-lived in the environment is
needed.
[0003] Hydrazone bond formation has been widely used to construct
thermodynamically stable, yet kinetically reversible, covalent
molecular complexes that are stable in aqueous solution near
neutral pH (Dirksen, et al., Nucleophilic Catalysis of Hydrazone
Formation and Transimination: Implications for Dynamic Covalent
Chemistry, J. Am. Chem. Soc., 128: 15602-15603 (2006);
Rodriguez-Docampo, Z., and S. Otto, Orthogonal or Simultaneous Use
of Disulfide and Hydrazone Exchange in Dynamic Covalent Chemistry
in Aqueous Solution, Chem. Commun., pages 5301-5303 (2008)). Bond
formation and dissociation is dynamic and rapid, often occurring
within seconds to minutes at room temperature (King, T. P., et al.,
Preparation of Protein Conjugates via Intermolecular Hydrazone
Linkage, Biochemistry (Mosc.), 25: 5774-5779 (1986); Dirksen, A.,
and P. E. Dawson, Rapid Oxime and Hydrazone Ligations with Aromatic
Aldehydes for Biomolecular Labeling, Bioconjug. Chem., 19:
2543-2548 (2008); and Nguyen, R., and I. Huc, Optimizing the
Reversibility of Hydrazone Formation for Dynamic Combinatorial
Chemistry, Chem. Commun., pages 942-943 (2003)). These reversible
bonds enable pathways for environmental degradation as they
dissociate at extreme pH or upon dilution. Custalcean and coworkers
employed hydrazone bond formation to construct a class of
self-assembled cations that associate strongly with anions
(Custelcean, R., et al., Aqueous Sulfate Separation by
Crystallization of Sulfate-Water Clusters, Angew. Chem. Int. Ed.,
54: 10525-10529 (2015); Custelcean, R., et al., Aqueous Sulfate
Separation by Sequestration of
[(SO.sub.4).sub.2(H.sub.2O).sub.4].sub.4--Clusters within Highly
Insoluble Imine-Linked Bis-Guanidinium Crystals, Chem.-Eur. J., 22,
1997-2003 (2016)). These complexes structurally resemble
conventional polyguanidines (e.g., chlorhexidine), a class of
widely used antimicrobials that are persistent and toxic.
SUMMARY OF THE INVENTION
[0004] According to at least one aspect of the invention, a
composition may include a compound of the formula:
##STR00001##
wherein R.sub.1 and R.sub.3 are, independently, one of a straight
chain or branched, saturated or unsaturated aliphatic group, a
5-member ring, or a 6-member ring, R.sub.1 and R.sub.3 are,
independently, optionally substituted one or more times, in the
case of either of R.sub.1 or R.sub.3 being a 6-member ring, the
6-member ring is optionally an aromatic ring, and in the case of
either of R.sub.1 or R.sub.3 having at least one substitution, a
first substitution is one of an alcohol group, an aldehyde group, a
5-member ring, a 6-member ring, a halide, a halide-diol, an ether,
and a straight or branched, saturated or unsaturated aliphatic
group.
[0005] According to a further aspect of the invention, the compound
may be one of the compounds disclosed in FIG. 5A, FIG. 5B, FIG. 5C
and FIG. 5D.
[0006] According to at least one aspect of the invention, a
composition may include a compound of the formula:
##STR00002##
wherein R.sup.1 and R.sup.2 independently represent: (1) hydrogen
(--H), or (2) an aliphatic (saturated or unsaturated, straight
chain or branched) functional group (e.g., C.sub.1-10 alkyl) that
may be substituted with additional aliphatic groups (e.g. -Me, -Et,
where the aliphatic portion ranges from C.sub.1 to C.sub.10),
phenolic, --OH groups, ethers (e.g. --OMe, --OEt, where the alkyl
portion of the ester ranges from C.sub.1 to C.sub.10), esters (e.g.
--CO.sub.2Me, --CO.sub.2Et, where the alkyl portion of the ester
ranges from C.sub.1 to C.sub.10), acids (e.g. boronic, --BO.sub.2,
or carboxylic, --CO.sub.2H), amines and ammoniums (e.g.
--NR.sup.3R.sup.4 or --(NR.sup.3R.sup.4R.sup.5).sup.+), alcohols
(e.g. --CH.sub.2OH where the alkyl portion of the alcohol ranges
from C.sub.1 to C.sub.10), thiol and thioesters (e.g. --SH, --SMe,
--SEt, where the alkyl portion of the thioester ranges from C.sub.1
to C.sub.10), halogens (e.g. --Cl, --Br), and/or a 1-2 ring
heterocycle that contains O, N and/or S as the heteroatom, such as
morpholine, or (3) an aromatic functional group (e.g.,
C.sub.6H.sub.5 or derivatives wherein one or more --H is
substituted with an alkyl (e.g., C.sub.1-10), with aliphatic groups
(e.g. -Me, -Et, where the aliphatic portion ranges from C.sub.1 to
C.sub.10), phenolic, --OH groups, ethers (e.g. --OMe, --OEt, where
the alkyl portion of the ester ranges from C.sub.1 to C.sub.10),
esters (e.g. --CO.sub.2Me, --CO.sub.2Et, where the alkyl portion of
the ester ranges from C.sub.1 to C.sub.10), acids (e.g. boronic,
--BO.sub.2, or carboxylic, --CO.sub.2H), amines and ammoniums (e.g.
--NR.sup.3R.sup.4 or --(NR.sup.3R.sup.4R.sup.5).sup.+), alcohols
(e.g. --CH.sub.2OH where the alkyl portion of the alcohol ranges
from C.sub.1 to C.sub.10), thiol and thioesters (e.g. --SH, --SMe,
--SEt, where the alkyl portion of the thioester ranges from C.sub.1
to C.sub.10), halogens (e.g. --Cl, --Br), and/or a 1-2 ring
heterocycle that contains O, N and/or S as the heteroatom, such as
pyridine or indole; R.sup.3, R.sup.4 and R.sup.5 independently
represent a hydrogen of aliphatic (saturated or unsaturated,
straight chain or branched, e.g., C.sub.1-10 alkyl) functional
group that may be substituted, for example, with additional
aliphatic groups (e.g. -Me, -Et, where the aliphatic portion ranges
from C.sub.1 to C.sub.10), --OH groups, ethers (e.g. --OMe, --OEt,
where the alkyl portion of the ester ranges from C.sub.1 to
C.sub.10), esters (e.g. --CO.sub.2Me, --CO.sub.2Et, where the alkyl
portion of the ester ranges from C.sub.1 to C.sub.10), acids (e.g.
boronic, --BO.sub.2, or carboxylic, --CO.sub.2H), amines and
ammoniums alcohols (e.g. --CH.sub.2OH where the alkyl portion of
the alcohol ranges from C.sub.1 to C.sub.10), thiol and thioesters
(e.g. --SH, --SMe, --SEt, where the alkyl portion of the thioester
ranges from C.sub.1 to C.sub.10), or halogens (e.g. --Cl,
--Br).
[0007] According to a further aspect of the invention, the compound
may be an active agent.
[0008] According to a further aspect of the invention, the active
agent may be formed by self-assembly of a first component molecule
and a second component molecule.
[0009] According to yet a further aspect of the invention, the
active agent may have antimicrobial activity.
[0010] According to another aspect of the invention, a method for
treating a pathogen or microbe may include applying an effective
amount of an active agent to a designated area or object, the
active agent being the compound described above.
[0011] According to a further aspect of the invention, the active
agent may be one of the compounds disclosed in FIG. 5A, FIG. 5B,
FIG. 5C and FIG. 5D, or FIG. 10 and FIG. 11.
[0012] According to another aspect of the invention, a
self-assembled active agent may be formed by a process including
covalently bonding at least a first component molecule and a second
component molecule, and the effective amount of the self-assembled
active agent is lower than the sum of the effective amounts of the
first component molecule and the second component molecule.
[0013] According to a further aspect of the invention, the first
component molecule may be an amine and the second component
molecule may be an aldehyde.
[0014] According to a further aspect of the invention, the first
component molecule may be an amine and the second component
molecule may be a ketone.
[0015] According to a further aspect of the invention, the covalent
bonding between the first component molecule and the second
component molecule may include the formation of a hydrazone
bond.
[0016] According to a further aspect of the invention, the first
component molecule may have two or more amine functional
groups.
[0017] According to a further aspect of the invention, the first
component molecule may be one of 1,3-diaminoguanidine and
aminoguanidine.
[0018] According to a further aspect of the invention, the second
component molecule may have one or more aldehyde functional
groups.
[0019] According to a further aspect of the invention, the second
component molecule may have three or more aldehyde functional
groups.
[0020] According to a further aspect of the invention, the second
component may be one of glyoxal, glutaraldehyde, benzylaldehyde,
phthalaldehyde, terephthalaldehyde, isophthalaldehyde,
benzene-1,3,5-tricarboxaldehyde, 2-bromoisophthalaldehyde,
4-tBu-2,6-diformylphenol, 4-Me-2,6-diformylphenol,
3,5-diformyl-2-propoxyphenylboronic acid, 2,5-thiophenedialdehyde,
and 2,5-furandialdehyde.
[0021] According to another aspect of the invention, a method for
killing a microbe may include treating a growth of the microbe with
an effective amount of a self-assembled active agent (e.g., a
compound disclosed herein that has self-assembled); an effective
amount of the self-assembled active agent may be achieved by adding
a combination of a pre-determined amount of a first component
molecule and a pre-determined amount of a second component
molecule, wherein the first component molecule and the second
component molecule are capable of self-assembly via the formation
of a covalent bond.
[0022] According to another aspect of the invention, a method of
producing a self-assembled active agent may include combining a
first component with a second component, wherein the first
component is a molecule with an amine functional group and the
second component is a molecule with an aldehyde or a ketone
functional group, wherein the first component, the second
component, and the combination of the first component and the
second component each has a bioactivity, and wherein the
bioactivity of the combination of the first component and the
second component is greater than the sum of the bioactivity of the
first component and the bioactivity of the second component.
[0023] According to a further aspect of the invention, the first
component and the second component may be capable of self-assembly
via the formation of a covalent bond.
[0024] According to a further aspect of the invention, the
formation of a covalent bond between the first component and the
second component may include the formation of a hydrazone bond.
[0025] We have developed a new class of antimicrobials (useful
against Gram-negative and Gram-positive bacteria, fungi, molds,
yeasts, and viruses) based on nontoxic aldehydes and ketones (see
the Figures). When treated with a potentiating agent (e.g.,
aminoguanidine or diaminoguanidine), a reversible covalent complex
is formed that surprisingly exhibits selective or narrow- or
broad-spectrum antimicrobial activity. Potencies of the resulting
complexes are up to 1000 times greater than the sum of their parts.
Owing to their surprisingly reversible nature, these complexes are
designed to dissociate to nontoxic subcomponents after use. This
degradation pathway minimizes the risks of collateral toxicity and
antimicrobial resistance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Advantages of embodiments of the present invention will be
apparent from the following detailed description of the exemplary
embodiments. The following detailed description should be
considered in conjunction with the accompanying figures in
which:
[0027] Exemplary FIG. 1 shows exemplary reversible interactions
which may be used to construct self-assembled complexes, including
self-assembled active agents, as described below.
[0028] Exemplary FIG. 2 shows an exemplary scheme for the
self-assembly of an active agent using a hydrazone bond through the
combination of isophthalaldehyde with either aminoguanidine or
1,3-diaminoguanidine as described below.
[0029] Exemplary FIG. 3 shows IR spectra of an aldehyde alone and
in combination with two different amines, demonstrating the
formation of the hydrazone bond, as described below.
[0030] Exemplary FIG. 4 shows general schema for some of the
self-assembled active agents described by the current invention as
described below.
[0031] Exemplary FIG. 5A, FIG. 5B, FIG. 5C and FIG. 5D show
structures for some particular self-assembled active agents as
described below; a crisscrossed bond indicates that a double bond
may be in either the cis or trans configuration.
[0032] Exemplary FIG. 6 shows the effect of varying weight ratios
of the component compounds on synergy (1/FICI) (FICI=fractional
inhibitory concentration indices) for a particular self-assembled
active agent as described below.
[0033] Exemplary FIG. 7 shows the effect of pH on synergy (1/FICI)
for a particular self-assembled active agent as described
below.
[0034] Exemplary FIG. 8 shows a general scheme describing the
formation of 2:1 (4) and 1:1 (5) adducts of mono-aldehydes or
ketones with diaminoguanidine (2) or aminoguanidine (1) as
described below.
[0035] Exemplary FIG. 9 shows synthesis, properties and end-of life
for reversible antimicrobials based on benzaldehyde (top) compared
to conventional polyguanide and quaternary ammonium (quat)
antimicrobials (bottom) as described below.
[0036] Exemplary FIG. 10 shows examples of the structures of
reversible antimicrobials.
[0037] Exemplary FIG. 11 shows additional examples of the
structures of reversible antimicrobials.
DETAILED DESCRIPTION OF THE INVENTION
[0038] Aspects of the invention are disclosed in the following
description and related drawings directed to specific embodiments
of the invention. Alternate embodiments may be devised without
departing from the spirit or the scope of the invention.
Additionally, well-known elements of exemplary embodiments of the
invention will not be described in detail or will be omitted so as
not to obscure the relevant details of the invention. Further, to
facilitate an understanding of the description, discussion of
several terms used herein follows.
[0039] As used herein, the word "exemplary" means "serving as an
example, instance or illustration." The embodiments described
herein are not limiting, but rather are exemplary only. It should
be understood that the described embodiment are not necessarily to
be construed as preferred or advantageous over other embodiments.
Moreover, the terms "embodiments of the invention", "embodiments"
or "invention" do not require that all embodiments of the invention
include the discussed feature, advantage, or mode of operation.
[0040] Unless defined otherwise, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which the invention belongs. As used
herein, the term "about" refers to a quantity, level, value, or
amount that varies by as much as 10% to a reference quantity,
level, value, or amount. Although any methods and materials similar
or equivalent to those described herein can be used in the practice
or testing of the present invention, the preferred methods and
materials are now described.
[0041] Other compounds may be added to the composition provided
they do not substantially interfere with the intended activity and
efficacy of the composition; whether or not a compound interferes
with activity and/or efficacy can be determined, for example, by
the procedures utilized below.
[0042] The amounts, percentages, and ranges disclosed herein are
not meant to be limiting, and increments between the recited
amounts, percentages, and ranges are specifically envisioned as
part of the invention. All ranges and parameters disclosed herein
are understood to encompass any and all subranges subsumed therein,
and every number between the endpoints. For example, a stated range
of "1 to 10" should be considered to include any and all subranges
between (and inclusive of) the minimum value of 1 and the maximum
value of 10 including all integer values and decimal values; that
is, all subranges beginning with a minimum value of 1 or more,
(e.g., 1 to 6.1), and ending with a maximum value of 10 or less,
(e.g. 2.3 to 9.4, 3 to 8, 4 to 7), and finally to each number 1, 2,
3, 4, 5, 6, 7, 8, 9, and 10 contained within the range.
[0043] "Biological activity" or, in context, "activity" refers to
the ability of a compound or composition to (i) prevent the growth
of a pathogen or microbe, (ii) inhibit the growth of a pathogen or
microbe, or (ii) substantially kill or eliminate a pathogen or
microbe population. An active agent is a compound or composition
which exhibits substantial biological activity.
[0044] The term "treat," "treating," or "treatment," as used
herein, refers to the use of a composition to reduce or prevent a
condition, symptom, or disease caused by a pathogen or microbe by
(i) preventing the growth of the pathogen or microbe, (ii)
inhibiting the growth of the pathogen or microbe, or (ii)
substantially killing or eliminating the pathogen or microbe. In
addition, the term "treat," "treating," or "treatment" may also
refer to the use of a composition to kill, reduce the population
of, or inhibit the growth of a pest or pest population.
[0045] "Microbe" as used herein is synonymous with "microorganism"
and may refer to a bacterium, fungus, algae, mold, protozoan,
yeast, or other unicellular organism, or a virus.
[0046] The term "effective amount" of a compound or property as
provided herein is meant such amount as is capable of performing
the function of the compound or property for which an effective
amount is expressed. As will be pointed out below, the exact amount
required will vary from process to process, depending on recognized
variables such as the compounds employed and the processing
conditions observed. Thus, it is not possible to specify an exact
"effective amount." However, an appropriate effective amount may be
determined by one of ordinary skill in the art using only routine
experimentation.
[0047] As used herein, "analog" or "chemical variant" of a compound
refers to a structural analog of the identified compound having a
similar structure and similar activity.
[0048] Objects treated by the methods described herein include
surfaces. Objects treated by the methods described herein also
include foods and beverages. Foods and beverages treated by the
methods described herein include meat, poultry, seafood, eggs,
nuts, fruits and vegetables. Particularly included are apples,
melons, apricots, peaches, pears, artichokes, beans, bell peppers,
carrots, celery, tomato, lettuce, and spinach. Foods particularly
include fresh-cut produce (e.g., fruits and vegetables) which is
produce that has been, for example, peeled, cut, sliced, or
shredded. The fresh-cut produce may be subsequently made into
juice, or dried or dehydrated or frozen by methods known in the
art. Objects treated by the methods described herein also include a
surface, such as a kitchen countertop.
[0049] Contacting or exposing objects with the antimicrobial
composition described herein (to reduce and/or kill bacteria) may
occur by conventional methods such as spraying or dipping or
immersion wherein the object is in contact with the antimicrobial
solution for a certain period of time (e.g., about 120
seconds).
[0050] Unless otherwise indicated, all numbers expressing
quantities of ingredients, properties such as molecular weight,
reaction conditions (e.g., reaction time, temperature), percentages
and so forth as used in the specification and claims are to be
understood as being modified in all instances by the term "about."
Accordingly, unless otherwise indicated, the numerical properties
set forth in the following specification and claims are
approximations that may vary depending on the desired properties
sought to be obtained in embodiments of the present invention. As
used herein, the term "about" refers to a quantity, level, value,
or amount that varies by as much as 10% to a reference quantity,
level, value, or amount.
[0051] The term "consisting essentially of" excludes additional
method steps or composition components that substantially interfere
with the intended activity of the method or composition, and can be
readily determined by those skilled in the art (for example, from a
consideration of this specification or practice of the invention
disclosed herein).
[0052] All of the references cited herein, including U.S. patents
and U.S. Patent Application Publications, are incorporated by
reference in their entirety.
[0053] A wide range of application rates of the compositions may be
suitable in accordance with the present methods. Those working in
this field would of course be readily able to determine in an
empirical manner the optimum rates of application for any given
combination of target microorganisms to be killed or eliminated.
The amount of composition used will be at least an effective amount
to reduce and/or kill microorganisms. The term "effective
microorganisms killing amount" as used herein, means the minimum
amount of composition needed to reduce and/or kill the number of
microorganisms on or in an object or area (e.g., soil, structures,
plants, or agricultural commodities such as grain or wood). Of
course, the precise amount of the composition needed will vary in
accordance with the particular composition used; the type of object
to be treated; the number of days of effectiveness needed; and the
environment in which the object is located. The precise amount of
the composition can easily be determined by one skilled in the art
given the teaching of this application. Other compounds may be
added to the composition provided they do not substantially
interfere with the intended activity of the composition; whether or
not a compound interferes with activity can be determined, for
example, by the procedures described below.
[0054] The optional carrier may be, for example, agronomically or
physiologically or pharmaceutically acceptable carriers known in
the art. The carrier component can be a liquid or a solid material.
The term "carrier" as used herein includes carrier materials such
as those described below. As is known in the art, the vehicle or
carrier to be used refers to a substrate such as a mineral oil,
paraffin, silicon oil, water, membrane, sachets, disks, rope,
vials, tubes, septa, resin, hollow fiber, microcapsule, cigarette
filter, gel, natural and/or synthetic polymers, elastomers or the
like. All of these substrates have been used to control and release
an effective amount of a composition containing the compounds
disclosed herein in general and are well known in the art. Suitable
carriers are well-known in the art and are selected in accordance
with the ultimate application of interest. Agronomically acceptable
substances include aqueous solutions, glycols, alcohols, ketones,
esters, hydrocarbons halogenated hydrocarbons, polyvinyl chloride;
in addition, solid carriers such as clays, laminates, cellulosic
and rubber matrices and synthetic polymer matrices, or the
like.
[0055] "Optional" or "optionally" means that the subsequently
described event or circumstance may or may not occur, and that the
description includes instances in which said event or circumstance
occurs and instances where it does not. For example, the phrase
"optionally comprising a known antimicrobial" means that the
composition may or may not contain a known antimicrobial and that
this description includes compositions that contain and do not
contain a known antimicrobial. Also, by example, the phrase
"optionally adding a known antimicrobial" means that the method may
or may not involve adding a known antimicrobial and that this
description includes methods that involve and do not involve adding
a known antimicrobial.
[0056] Compositions containing one or more (e.g., two) of the
compounds described herein may contain one specific compound or may
not contain that specific compound. For example, a composition may
contain
##STR00003##
or the composition may not contain
##STR00004##
[0057] The invention illustratively disclosed herein suitably may
be practiced in the absence of any element (e.g., method steps or
composition components) which is not specifically disclosed herein.
Further, the invention described herein may include any one or more
of the listed active agents described herein, and in the case of
the invention including a single active agent, any other active
agent may be optionally excluded.
[0058] According to at least one embodiment, self-assembled active
agents may be produced using known processes. A self-assembled
active agent may be the result of the assembly of two or more
components. For example, the self-assembled active agent may be a
complex formed by the covalent bonding of two or more component
molecules. The self-assembly may occur under a variety of
conditions, depending on the desired application. According to at
least some embodiments, the self-assembly occurs at room
temperature in an aqueous medium. Further, a controlling factor for
self-assembly may be concentration of the self-assembled active
agent and/or components. For example, in the case where the active
agent is sufficiently diluted, the assembly may reverse, and the
active agent may break apart into its separate components. The
self-assembled active agent may be in the form of an individual
molecule, consisting of as little as two components. Alternatively,
the self-assembled active agent may be an oligomer or a
polymer.
[0059] The active agent may have one or more activities. For
example, the active agent may be an antimicrobial agent, such as an
antibacterial agent. The active agent may also be a biocide such as
an herbicide, a pesticide, or an antiviral agent. Additionally or
alternatively the active agent may be a preservative, an
antifouling agent, or a disinfectant. In the case of the active
agent being active against a microbe, bacterium, or virus, the
active agent may be termed as having bioactivity. The active agent
may also be a sensor agent, such as for a particular molecule or
for pH.
[0060] The bioactivity of a compound or active agent means the
strength of the compound or active agent to kill, treat, reduce the
number of, or inhibit growth of a microbe or other biological
entity. For example, in the case of inhibition of growth of an
organism, bioactivity is inversely proportional to the minimum
concentration needed to inhibit the growth of the organism. The
bioactivity of a compound or active agent also means the strength
of the compound or active agent to remove a microbe or other
biological entity depending on the carrier system such as a gel or
encapsulating matrix; also the compound or active agent may be a
cationic surfactant which can "sweep away" microbes from
surfaces.
[0061] The components of the active agent may be benign and/or
biodegradable compounds. Exemplary components which may be used in
an active agent may be amines, aldehydes, and/or ketones. For the
purposes of this disclosure, an aldehyde is a molecule with at
least one aldehyde functional group, a ketone is a molecule with at
least one ketone functional group, and an amine is a molecule with
at least one amine functional group. In the case of an amine and an
aldehyde being two components to form an active agent, the
self-assembly may be achieved via dehydration synthesis. The active
agent may thus be formed via a covalent bond, such as a hydrazone
bond. Exemplary amines for a component in an active agent may
include 1,3-diaminoguanidine and aminoguanidine. Exemplary
aldehydes for a component in an active agent may include glyoxal,
glutaraldehyde, benzylaldehyde, phthalaldehyde, terephthalaldehyde,
isophthalaldehyde, benzene-1,3,5-tricarboxaldehyde,
2-bromoisophthalaldehyde, 4-tBu-2,6-diformylphenol,
4-Me-2,6-diformylphenol, 3,5-diformyl-2-propoxyphenylboronic acid,
2,5-thiophenedialdehyde, and 2,5-furandialdehyde. The active agent
may alternatively be formed via an oxime bond, a boronic acid
adduct, or any other suitable reversible bond scheme. Exemplary
reversible interactions which may be used to construct
self-assembled complexes, including self-assembled active agents,
are shown in FIG. 1 (adapted from DOI: 10.1002/anie.201610372 and
references therein).
[0062] An exemplary scheme for the self-assembly of an active agent
using a hydrazone bond is shown in FIG. 2 and FIG. 8.
[0063] One general procedure for preparation of the antimicrobials
(e.g., FIG. 8) is by treating an aldehyde (e.g., 20 mg) or ketone
(e.g., 20 mg) with aminoguanidine HCl stock solution (e.g., 180 mg;
37 wt % aminoguanidine HCl in dH.sub.2O) or diaminoguanidine.
Reactions proceed within seconds but were typically heated for at
least about 30 min at about 70.degree. C. to ensure completion.
Reactions can be typically run at about 20.degree. to about
70.degree. C. for about 1 minute to about 48 h; lower and higher
temperatures also afford the same complexes, albeit at different
rates. Typically reactions were run at neutral pH; lower and higher
pH affords the same complexes at different rates and purity.
[0064] Complexes were constructed from non-toxic aldehydes or
ketones and aminoguanidine or diaminoguanidine subcomponents
through a dynamic covalent hydrazone linkage (typical reaction
conditions: at least about 30 minutes at about 70.degree. C. and
about neutral pH). This reversible bond dissociates on the order of
seconds to hours when exposed to dilution, changes in pH,
temperature, or chemical treatment (e.g., hydrazine or
hydroxylamine). Hydrazone bond reversibility is well documented in
the scientific literature (Nguyen, R., and I. Huc, Chem. Commun.,
8: 942-943 (2003)). Association constants for hydrazone bonds (1:1
hydrazine to aldehyde) in water are typically 10.sup.5-10.sup.7
M.sup.-1. An association constant of 10.sup.6 M.sup.-1 would be
>99% complex as a 1 wt % solution, and dissociate .about.94% to
its subcomponents upon dilution of a 1 L product in a 25-meter
swimming pool (375,000 Liters). By providing a novel degradation
pathway through dissociation, reversible antimicrobials are
produced. Reversible and "controllable" antimicrobial agents are
put forward as a way to limit the development of collateral
antimicrobial resistance and toxicity through environmental
persistence. The general advantage of these microbial agents is
that they are active when present in their complexed state and can
thus substitute for toxic, nonrenewable antiseptics, disinfectants,
and preservatives that are used so prevalently in many
consumer/medical products. However, when antimicrobial activity is
no longer needed, these active complexes can be de-activated via
dissociation, for example though changes in concentration, pH,
temperature, or salt concentration.
[0065] Although mechanistic investigations are ongoing, without
being bound by theory these antimicrobials are envisioned to
inhibit microbial growth through multiple mechanisms (e.g.,
membrane disruption, inhibition of oxidative phosphorylation
similar to Robenidine, etc.). Minimum inhibitory concentrations for
several complexes were as low as 6-70 ppm for example against
resilient strains of Pseudomonas aeruginosa and Aspergillus
brasiliensis. This high degree of potency is comparable to
conventional, market-leading antibiotics.
[0066] Aldehyde and ketone components used to produce the novel
antimicrobials may be agriculturally derived (e.g., benzaldehyde,
cuminaldehyde, citral from Prunus, cumin and lemongrass-based
feedstocks), which could create a novel market for these green
product substances. In addition, plant extracts, oils, flavors or
fragrances can be used to produce the novel antimicrobials. The
antimicrobial complexes themselves may find use as preservatives
that would minimize food and water waste. These substances may also
be used as antimicrobials, antibiotics, antiparasitics, repellents
and pesticides (e.g. against insects), and herbicides and could
replace current synthetic chemicals which are generally more toxic
and contribute to microbial and pest resistance. These substances
could substitute for current pesticides, adjuvants/boosters,
anti-biofilm actives, probiotics, disinfectants, antiseptics,
antibiotics (topical and oral), and preservatives. These
antimicrobials may also be delivered through incorporation of the
complex or a subcomponent in packaging. The antimicrobials could be
used to coat or be incorporated into bottles, packaging, films,
transfer lines/tubing, in process--cleaning tanks, pump surfaces
etc.
[0067] One big advantage of these antimicrobials is that they
exhibit a limited post-use lifetime, thus minimizing opportunities
for sub-inhibitory microbial exposure and resulting in development
of antimicrobial resistance. Thus antibiotics currently used for
agriculture may be replaced by these inexpensive, non-toxic,
biobased, and reversible antimicrobials.
[0068] To summarize the advantages of this system more directly, in
normal use of the consumer product the product would provide
maximum efficacy when the complex is together, likely, for example,
when both components are at a high concentration. Thus, it is
active when needed. However, after use, when efficacy is no long
needed and the molecules are being washed down the drain, for
example, the complex would naturally and immediately become
diluted, whereby the separate molecules are benign and represent
little risk to the environment. In the case of agriculture (e.g.,
when acting as a miticide, pest control, or food preservative), the
net effect in almost all imaginable applications is that the
complex would become immediately benign after use. It should be
noted that the complex could be used in food or feed supplements
which lose efficacy in the stomach or soon after digestion.
[0069] Reversible antimicrobials, such as those described herein,
are relatively safe and benign, and thus would displace many of the
current antimicrobials being banned or heavily scrutinized by
regulatory agencies and consumers. In cases where current biocides
are being heavily regulated, reversible analogues could completely
substitute for these products by offering the novel advantage of
controlled or predictable dissociation.
[0070] While this invention may be embodied in many different
forms, there are described in detail herein specific preferred
embodiments of the invention. The present disclosure is an
exemplification of the principles of the invention and is not
intended to limit the invention to the particular embodiments
illustrated. Furthermore, the invention encompasses any possible
combination of some or all of the various embodiments and
characteristics described herein and/or incorporated herein. In
addition the invention encompasses any possible combination that
also specifically excludes any one or some of the various
embodiments and characteristics described herein and/or
incorporated herein.
[0071] The following examples are intended only to further
illustrate the invention and are not intended to limit the scope of
the invention as defined by the claims.
Examples
[0072] Antimicrobial Agents: Self-assembled active agents were
created using the components shown in Table 1.
[0073] The formation of complexes through a hydrazone bond was
confirmed through IR spectroscopy. FIG. 3 shows exemplary IR
spectrographs for teraphthaldehyde only (top), and teraphthaldehyde
combined with aminoguanidine or diaminoguanidine (middle and
bottom, respectively). The concomitant disappearance of the
aldehyde peak (.about.1650-1700 cm.sup.-1) and appearance of the
hydrazone peak (.about.1550-1650 cm.sup.-1) is clear for both of
the middle and bottom spectra.
[0074] To compare antimicrobial efficacy of self-assembled
complexes to their components, fractional inhibitory concentration
indices (FICIs) were calculated from measured minimum inhibitory
concentrations (MICs) against Pseudomonas aeruginosa and
Escherichia coli. The MIC of each substance was determined
according to standard guidelines in cation-adjusted Mueller-Hinton
broth at a total volume of .about.100 .mu.l with test
concentrations decreasing two-fold to span the
empirically-determined MIC (J. Med. Chem., 59: 2126-2138 (2016)).
Wells contained starting microbe concentrations of approximately
10.sup.7 cells/mL. Absorbance at 600 nm (abs600) was determined
immediately after inoculation using a 96 well plate reader. Plates
were incubated at 37.degree. C. and abs600 measured after 24 hours.
For the purposes of these experiments, minimum inhibitory
concentrations are defined as the minimum concentration observed to
inhibit microbial growth over this time span, with a change in
abs600 less than or equal to 0.1.
[0075] Following MIC testing, FICI were calculated as shown in
Equation 1:
F .times. .times. I .times. .times. C .times. .times. I X .times. Y
= MIC .times. .times. X c .times. o .times. m .times. b .times. i
.times. n .times. a .times. t .times. i .times. o .times. n MIC
.times. .times. X a .times. l .times. o .times. n .times. e + MIC
.times. .times. Y c .times. o .times. m .times. b .times. i .times.
n .times. a .times. t .times. i .times. o .times. n MIC .times.
.times. Y a .times. l .times. o .times. n .times. e ( Equation
.times. .times. 1 ) ##EQU00001##
[0076] The FICI can be used to quantify the synergy between two
components (X and Y). Specifically, 1/FICI can be used as a measure
of synergy, interpreted as factors by which the potency of a given
combination is greater than the sum of its parts (see Journal of
Antimicrobial Chemotherapy, 52: 1 (2003)). For example, in the
present invention, synergy may be found when the effective amount
of the self-assembled active agent is lower than the sum of the
effective amounts of the two or more component molecules.
[0077] Neutral oxygen and sulfur-containing analogues of A and B
were treated with aldehydes 1-7. Under otherwise identical
conditions, these neutral analogues failed to exhibit significant
synergies (1/FICI<5) (data not shown).
[0078] MICs for combinations of A and B with aldehydes 1-13 were
measured as against P. aeruginosa and E. coli. General schema for
some of the studied compounds are shown in FIG. 4. Specifically
shown in FIG. 4 are general structures showing compound B combined
in a complex with any of compounds 6, 8, or 11 (top left), 12 or 13
(top right), 5 (bottom left), and 1 or 2 (bottom right). It is
noted that for designations R.sub.1, R.sub.2, R.sub.3, and X, the
represented atom(s) need not be the same within the same structure.
For example, the top left structure represents B+8 if R.sub.1 is H
and R.sub.2 represents both H and Br. This simplified version is
thus used for brevity. The specific structures formed by the
combinations of each of A and B with compounds 1, 2, and 4-13 can
be found in the list in FIG. 5A, for example.
[0079] An exemplary set of measured MICs is shown in Table 2. For
the data in Table 2, when multiple components were used to form a
complex, the amine component was present in excess of a 1:1 molar
ratio.
[0080] The MICs determined as per above were then used to calculate
FICIs. Synergism (1/FICI) was then tabulated, as shown in Table 3.
Note that 1/FICI values varied with subcomponent ratio; unless
otherwise noted, the values shown in Table 3 represent a molar
ratio of 6:1, amine:aldehyde.
[0081] It is noted that of the studied compounds, the aldehydes
with the strongest synergies in FIG. 5A, FIG. 5B, FIG. 5C, and FIG.
5D generally are aromatic compounds with two or more aldehyde
groups. Further, though B tended to exhibit synergy with compound
5, 6, and 7, glyoxal (1) exhibited greater synergy with A than B by
a small but notable margin.
[0082] In addition, relative concentration of components was
studied. Components A and 5 were combined in varying ratios to
determine a maximum effective FICI. The conditions were that P.
aeruginosa was grown in Mueller-Hinton broth under aerobic
conditions and with a starting concentration of 10.sup.5 cells/mL.
Growth was assessed after 24 hours at 37.degree. C. The weight
ratios of A:5 were 1:1, 2:1, 4:1, 8:1, 16:1, 32:1, and 64:1. The
results are shown in FIG. 6. As can be seen, the maximum synergy
was achieved with the 8:1 weight ratio.
[0083] The effect of pH on synergy was also studied. Components B
and 7 were combined in a 3:1 ratio (B:7). P. aeruginosa was grown
in Mueller-Hinton broth under aerobic conditions and with a
starting concentration of 10.sup.5 cells/mL. Growth was assessed
after 24 hours at 37.degree. C. The results are shown in FIG. 7.
Synergy decreased markedly as pH diverged from 7.
[0084] Other Activities: Activity against the toxin-producing
blue-green algae (cyanobacteria) Microcystis aeruginosa was also
observed in a combination of B+6 (MIC (wt %) Component B: 0.001;
Component 6: 0.0001). Thus, the agents also have activity as
against photosynthetic organisms (e.g., algae, plants) and/or as an
herbicide.
[0085] Additional Examples. Formulas: Manual Dish Cleaner (MDC) and
All Purpose Cleaner (APC) obtained from UL's Prospector
(www.ulprospector.com; accessed 4 PM, 9-15-17): MDC: Water 78.0%,
Plantapon 611L UP (Sodium Laureth Sulfate, Lauryl Glucoside,
Cocoamidopropyl Betaine, 22.0%); APC: Water 91.68%; Glucopon 420 UP
(Caprylyl//Myristyl Glucoside 3.50%, Citric Acid 0.40%, NaOH 0.52%,
NaHCO.sub.30.40%, Ethanol 3.50%).
[0086] General procedure for preparation of actives: Complexes were
formed by treating 20 mg of aldehyde or ketone with 180 mg of
aminoguanidine HCl stock solution (37 wt % aminoguanidine HCl in
dH.sub.2O) and heating at 60.degree. C. for 48 h. The resulting
product mixtures were subsequently screened for antimicrobial
activity.
[0087] Minimum inhibitory concentrations (MIC) determination: MIC
were determined similarly as previously reported (Design and
Testing of Safer, More Effective Preservatives for Consumer
Products-ACS Sustainable Chemistry & Engineering (ACS
Publications) with one exception: actives were dissolved in an
all-purpose cleaner and diluted in Mueller Hinton (MH) broth. A
cleaning formulation (generic All Purpose Cleaner or Manual Dish,
as mentioned in "Formulas") was used to test compatibility of
actives with a representative product formulation.
[0088] Viability of microbes in formula over time: The viability of
microorganisms were determined by adding complexes in 0.05-1 wt %
to formulations (all-purpose cleaner and manual dish) and
inoculation with Aspergillus brasiliensis (ATCC 16404) to make a
total cell concentration of .about.1.times.10.sup.6 spores/mL. The
total volume of the mixture was 5 mL. The inoculated mixture was
kept in a shaker at 30.degree. C. for 7 days. Microorganism
viability was determined by plating 100 .mu.m of inoculated mixture
on MH agar plates on days 0, 3, and 7.
[0089] Results and discussion: Following treatment with
aminoguanidine, a library of 54 aldehydes were evaluated as fungal
inhibitors (Table 4; conditions: spores/mL, time, temp). The most
potent of these complexes were re-evaluated alongside parent
aldehydes under similar experimental conditions (Table 5;
conditions: spores/mL, time, temp).
[0090] Surprisingly aminoguanidine complexes with benzaldehydes
were generally more potent than their parent aldehydes. Increases
in potency surprisingly ranged from one to two orders of magnitude
(Table 5). The most potent of these complexes were added in formula
(all-purpose cleaner and manual dish) at 0.1 wt %. A. brasiliensis
cell counts were monitored and counted over seven days.
[0091] The potency of the aminoguanidine complexes against microbes
were affected by the formulation that they were placed in. The
manual dish formulation surprisingly inhibited the potency of the
aminoguanidine complex against the microbes, as observed by the
logarithmic reduction of one (Table 6).
[0092] Without being bound by theory, the reversible complexes are
hypothesized to disrupt cellular membranes in a manner analogous to
quaternary ammonium compounds (quats) and guanide based
antimicrobials, such as chlorhexidine and
polyhexamethyleneguanidine (Jennings, M. C., et al., ACS Infect.
Dis., 1: 288-303 (2015)). In contrast to these conventional
antimicrobials, reversible complexes are designed to dissociate to
nontoxic, biodegradable subcomponents after use. This process is
anticipated to minimize collateral toxicity and antimicrobial
resistance.
[0093] Producers are facing growing restrictions on use of biocides
with poor human and environmental Producers health attributes.
Reversible antimicrobials, such as those described herein, may
compete with current products where consumer and environmental
safety is a prominent concern. In cases where current biocides are
being heavily regulated, reversible analogues could completely
substitute for these products by offering the novel advantage of
controlled or predictable dissociation.
[0094] Antibiotic resistant infections kill approximately 700,000
people per year. If resistance trends continue, global annual GDP
could be reduced by 2-3.5% by 2050, a loss of $60-$100 trillion of
cumulative economic output. The persistence of antibiotics that
linger in the environment long after their targeted use is a major
cause of this problem. Antibiotics currently used for agriculture
may be replaceable by inexpensive, biobased, and non-toxic
reversible antimicrobials described herein.
[0095] Table 7 surprisingly shows good to excellent performance of
aminoguanidine-cuminaldehyde complex in home cleaning formulations.
This complex was deactivated by high levels of ionic surfactants,
such as in the manual dish formulation. Aminoguanidine adducts of
more hydrophilic aldehydes (i.e., 4-hydroxybenzaldehyde,
2,6-dimethoxybenzaldehyde, 2,4,6-trimethoxybenzaldehyde,
m-anisaldehyde) circumvented deactivation in this manner and
enabled effective preservation of the high surfactant manual dish
formula.
[0096] Tables 8 and 9 show that the addition of aminoguanidine
surprisingly increased the antimicrobial properties of complex
mixtures of flavors, fragrances and bulk plant extracts and oils
that are often rich sources of bioactive aldehydes. Increases in
potency were typically one to two orders of magnitude. So the
second component can be plant extracts, oils, flavors or
fragrances.
[0097] Conclusions: Treatment of aldehydes and ketones with
aminoguanidine or diaminoguanidine surprisingly affords complexes
that exhibit antimicrobial potencies that may be orders of
magnitude greater than the sum of their parts. Because complex
formation is surprisingly reversible, products dissociate due to
thermodynamic changes such as dilution or pH. This property appears
to be general to a broad class of substrate aldehydes and ketones,
surprisingly enabling the activation of nontoxic subcomponents. As
in several of the aforementioned cases (e.g., cuminaldehyde,
benzaldehyde, syringaldehyde, vanillin) these subcomponents may be
agriculturally-derived, nontoxic and biodegradable. Compared to
covalent analogues (e.g., chlorhexidine,
polyhexamethyleneguanidine, quaternary ammonium compounds), this
class of reversible compounds will minimize the potential for
collateral toxicity and antimicrobial resistance by dissociating to
nontoxic subcomponents in the environment.
[0098] The invention illustratively disclosed herein suitably may
be practiced in the absence of any element (e.g., method (or
process) steps or composition components) which is not specifically
disclosed herein. Thus the specification includes disclosure by
silence ("Negative Limitations In Patent Claims," AIPLA Quarterly
Journal, Tom Brody, 41(1): 46-47 (2013): [0099] " . . . Written
support for a negative limitation may also be argued through the
absence of the excluded element in the specification, known as
disclosure by silence . . . . [0100] Silence in the specification
may be used to establish written description support for a negative
limitation. As an example, in Ex parte Lin [No. 2009-0486, at 2, 6
(B.P.A.I. May 7, 2009)] the negative limitation was added by
amendment . . . . In other words, the inventor argued an example
that passively complied with the requirements of the negative
limitation . . . was sufficient to provide support . . . . [0101]
This case shows that written description support for a negative
limitation can be found by one or more disclosures of an embodiment
that obeys what is required by the negative limitation . . . ."
[0102] The foregoing description and accompanying figures
illustrate the principles, preferred embodiments, and modes of
operation of the invention. However, the invention should not be
construed as being limited to the particular embodiments discussed
above. Additional variations of the embodiments discussed above
will be appreciated by those skilled in the art.
[0103] Therefore, the above-described embodiments should be
regarded as illustrative rather than restrictive. Accordingly, it
should be appreciated that variations to those embodiments can be
made by those skilled in the art without departing from the scope
of the invention as defined by the following claims.
[0104] The composition when it contains only one active compound
does not contain the following compounds:
##STR00005## ##STR00006## ##STR00007##
[0105] This trypanocidal compound is not used by itself as a
trypanocidal compound:
##STR00008##
[0106] This anti-malarial compound is not used by itself as an
anti-malarial compound:
##STR00009##
[0107] This anti-protozoa and anti-bacterial compound is not used
by itself as an anti-protozoa and anti-bacterial compound:
##STR00010##
[0108] This anti-fungal compound is not used by itself as an
anti-fungal compound:
##STR00011##
[0109] Other embodiments of the invention will be apparent to those
skilled in the art from a consideration of this specification or
practice of the invention disclosed herein. It is intended that the
specification and examples be considered as exemplary only, with
the true scope and spirit of the invention being indicated by the
following claims.
TABLE-US-00001 TABLE 1 Exemplary Components Compound Name
(designation) Compound Structure Amines 1,3-diaminoguanidine (A)
##STR00012## aminoguanidine (B) ##STR00013## Aldehydes glyoxal (1)
##STR00014## glutaraldehyde (2) ##STR00015## benzylaldehyde (3)
##STR00016## phthalaldehyde (4) ##STR00017## terephthalaldehyde (5)
##STR00018## isophthalaldehyde (6) ##STR00019##
benzene-1,3,5-tricarboxaldehyde (7) ##STR00020##
2-Bromoisophthalaldehyde (8) ##STR00021## 4-tBu-2,6-diformylphenol
(9) ##STR00022## 4-Me-2,6-diformylphenol (10) ##STR00023##
3,5-Diformy1-2- propoxyphenylboronic acid (11) ##STR00024##
2,5-thiophenedialdehyde (12) ##STR00025## 2,5-furandialdehyde (13)
##STR00026##
TABLE-US-00002 TABLE 2 MICs for Lone Components and Complexes
Conditions Component MIC (wt %) alone A 0.3.sup.i B >2.sup.i 1
0.04.sup.i 5 0.3.sup.i 7 0.3.sup.i A + 1 A 0.008.sup.i 1
0.001.sup.i A + 5 A 0.06.sup.i 5 0.01.sup.i A + 7 A 0.02.sup.i 7
0.003.sup.i B + 1 B 4.sup.i 1 0.7.sup.i B + 5 B 0.06.sup.i 5
0.01.sup.i B + 7 B 0.002.sup.i 7 0.0003.sup.i B + 8 B 0.004.sup.ii
8 0.0004.sup.ii B + 9 B 0.00005.sup.ii 9 0.00001.sup.ii B + 10 B
0.02.sup.ii 10 0.002.sup.ii B + 11 B 0.03.sup.ii 11 0.003.sup.ii B
+ 12 B 0.007.sup.ii 12 0.001.sup.ii B + 13 B 0.01.sup.ii 13
0.005.sup.ii .sup.iP. aeruginosa; .sup.iiE. coli
TABLE-US-00003 TABLE 3 Synergism (1/FICI) of Several Aldehydes and
Amines Component A B 1 20 0.1 2 3 <5 3 <5 <5 4 3 <5 5
20 20 6 30 200 7 20 1000* *extrapolated from eight FICI
measurements where the weight ratio of B:7 varied from 1:1 to
9:1.
TABLE-US-00004 TABLE 4 Minimum inhibitory concentrations (MICs) of
aminoguanidine-aldehyde adducts against A. brasiliensis ATCC16404.
(4 .times. 10.sup.5 spores/mL starting spore counts) MIC Entry
ALDEHYDE (R1, R2 = H for all) (wt %) 1 4-isobutylbenzaldehyde
0.0074 2 4-tert-butylbenzaldehyde 0.0298 3 4-butylbenzaldehyde
0.1190 4 4-octylbenzaldehyde 0.0149 5 2-ethoxybenzaldehyde 0.0149 6
benzaldehyde, redistilled 0.1190 7 cuminaldehyde, stock 0.0074 8
o-tolualdehyde 0.0595 9 p-tolualdehyde 0.1190 10
3-pyridinecarboxaldehyde 0.1190 11 m-tolualdehyde 0.1190 12
m-anisaldehyde 0.0595 13 cuminaldehyde, from oil 0.0149 14
cuminaldehyde, from bath 0.0298 15 veratraldehyde 0.0149 16
2,6-dimethylbenzaldehyde 0.0298 17 2-bromoisophthalaldehyde 0.0074
18 2-hydroxy-5-methyl-1,3- 0.0149 benzenedicarboxaldehyde 19
2,5-thiophenedicarboxaldehyde 0.0149 20 2,5-furandicarboxaldehyde
0.0074 21 3,4-dihydroxybenzaldehyde 0.0595 22
2,6-dimethoxybenzaldehyde 0.0149 23 2,5-dimethoxybenzaldehyde
0.0149 24 2,4-dimethoxybenzaldehyde 0.0149 25
2,4,6-trihydroxybenzaldehyde 0.0298 26 3,4,5-trimethoxybenzaldehyde
0.4762 27 2,4,5-trimethoxybenzaldehyde 0.4762 28
2,3,4-trimethoxybenzaldehyde 0.1190 29 2,4,6-trimethoxybenzaldehyde
0.0595 30 2,3-dimethoxybenzaldehyde 0.0298 31
3,5-dimethoxybenzaldehyde 0.0595 32 3,5-dihydroxybenzaldehyde
0.1190 33 2,5-dihydroxybenzaldehyde 0.1190 34
2,4-dihydroxybenzaldehyde 0.2381 35 4-hydroxybenzaldehyde 0.0298 36
4,6-dimethoxysalicylaldehyde 0.0298 37 2,3-dihydroxybenzaldehyde
0.0149 38 3-hydroxybenzaldehyde 0.0149 39
4-hydroxyl-3-methoxycinnamaldehyde 0.0298 see entry 34 40
2-hydroxyl-4-methoxybenzaldehyde 0.0149 41
3,4-dihydroxy-5-methoxybenzaldehyde 0.0595 42
3,4-dihydroxy-5-hydroxybenzaldehyde 0.0298 43 Syringaldehyde 0.0149
44 4-ethoxybenzaldehyde 0.0595 45
2,6-dimethoxy-4-hydroxybenzaldehyde 0.2381 46
1,3,5-triformylbenzene 0.4762 47 p-anisaldehyde 0.1190 48
o-anisaldehyde 0.0298 49 vanillin 0.4762 50 o-vanillin 0.0595 51
isovanillin 0.0595 52 vanillin acetate 0.2381 53 vanillin
isobutyrate 0.1190
TABLE-US-00005 TABLE 5 Minimum inhibitory concentrations of
aminoguanidine complexes compared to subcomponents (aldehyde,
aminoguanidine or biocide standard Kathon CG) against A.
brasiliensis ATCC 16404. MIC MIC (wt %) ALDEHYDE (wt %) sub- Entry
(R1, R2 = H for all) Complex component 1 4-isobutylbenzaldehyde
0.0595 0.4762 4 4-octylbenzaldehyde 0.0595 0.4762 5
2-ethoxybenzaldehyde 0.0595 0.4762 7 cuminaldehyde, stock
<0.0037 0.4752 15 veratraldehyde 0.0595 0.4762 17
2-bromoisophthalaldehyde <0.0037 0.0595 18
2,5-dihydroxybenzaldehyde >0.4762 >0.4762 19
2-hydroxy-5-methyl-1,3- <0.0037 0.0595 benzenedicarboxaldehyde
20 2,5-thiophenedicarboxaldehyde <0.0037 0.0595 21
2,5-furandicarboxaldehyde 0.0149 0.1190 24
2,5-dimethoxybenzaldehyde 0.1190 0.2381 25
2,4-dimethoxybenzaldehyde 0.0298 0.4762 38
2,3-dihydroxybenzaldehyde >0.4762 >0.4762 39
3-hydroxybenzaldehyde >0.4762 0.1190 41 2-hydroxyl-4- 0.0298
0.2381 methoxybenzaldehyde 44 syringaldehyde 0.1190 >0.4762 --
Amino Guanidine >0.4762 -- Kathon cg 0.0149
TABLE-US-00006 TABLE 6 Viability of microorganisms over seven days,
measured by the logarithmic reduction in cell count of A.
Brasiliensis (initial concentration = 5 .times. 10.sup.6 cells/mL).
Log Log Reduction Reduction ALDEHYDE in APC in MDC Entry (R1, R2 =
H for all) formula formula 7 cuminaldehyde, stock 5 1 17
2-bromoisophthalaldehyde 2 1 19 2-hydroxy-5-methyl-1,3- 4 1
benzenedicarboxaldehyde 20 2,5-thiophenedicarboxaldehyde 2 1 21
2,5-furandicarboxaldehyde 1 1 25 2,4-dimethoxybenzaldehyde 6 1 41
2-hydroxyl-4- 1 1 methoxybenzaldehyde -- Kathon cg 6 6
TABLE-US-00007 TABLE 7 Preservative Test Results of Reversible
Antimicrobial in Home Cleaning Formulations Log reduction in
formula Aspergillus Pseudomonas Concentration brasillensis,
aeruginosa Formula Antimicrobial (wt, %) ATCC16404 ATCC9027 Shower
Spray Aminoguanidine + cuminaldehyde 1 Fail* Pass Shower Spray
Aminoguanidine + cuminaldehyde 0.2 Fail* Pass Window Cleaner
Aminoguanidine + cuminaldehyde 0.2 Pass Pass All Purpose
Aminoguanidine + cuminaldehyde 0.1 Pass Pass Cleaner Toilet Cleaner
Aminoguanidine + cuminaldehyde 0.2 Pass Pass Bath Cleaner
Aminoguanidine + cuminaldehyde 0.2 Fail Pass Hand soap
Aminoguanidine + cuminaldehyde 0.2 Pass Pass Hand lotion
Aminoguanidine + cuminaldehyde 0.5 Pass Pass Manual Dish
Aminoguanidine + cuminaldehyde 1 Fail** Fail** Manual Dish
Aminoguanidine + 4- 1 Pass ND hydroxybenzaldehyde Manual Dish
Aminoguanidine + 2,4,6- 1 Pass ND trimethoxybenzaldehyde Manual
Dish Aminoguanidine + m-anisaldehyde 1 Pass ND Manual Dish
Aminoguanidine + 2,6- 1 Pass ND dimethoxybenzaldehyde Key 6 log
(<1 wk) 3 log (<1 wk) fail* <3 log (2 wk) fail**
TABLE-US-00008 TABLE 8 Aminoguanidine may enhance the antimicrobial
properties of plant extracts and oils (E. coli ATCC 8739) MIC after
amino- guanidine Factor addition MIC Essential increase Extract or
oil wt %) Oil (wt %) in potency 1 Bergamont 1.25 greater than 2.5 2
2 Grapefruit 2.5 greater than 2.5 1 3 Orange greater than 2.5
greater than 2.5 1 4 Spearmint 1.25 greater than 2.5 2 5 Cinnamon
0.0390625 0.15625 4 6 Lavender 2.5 greater than 2.5 1 7 Patchouli
greater than 2.5 greater than 2.5 1 8 Tea Tree Oil 2.5 1.25 0.5 9
Clary Sage 2.5 greater than 2.5 1 10 Lemongrass 0.15625 2.5 16 11
Lemon 1.25 greater than 2.5 2 12 Peppermint 2.5 greater than 2.5 2
13 Eucalyptus greater than 2.5 greater than 2.5 1 14 Lime 2.5
greater than 2.5 1 15 Rosemary 2.5 2.5 1 15 Vanilla 1.25 2.5 2 17
Vetiver 1.25 greater than 2.5 2 18 Bay Leaf 2.5 2.5 1 19 Cinnamon
cassia 0.0390625 0.078125 2 20 Tonka Bean 2.5 1.25 0.5 21 Cedarwood
greater than 2.5 greater than 2.5 1 22 Sandalwood 1.25 greater than
2.5 2 23 Clove 2.5 1.25 0.5 24 Oregano 0.3125 0.15625 0.5
TABLE-US-00009 TABLE 9 Aminoguanidine may enhance the antimicrobial
properties of flavors/fragrances (E. coli ATCC 9739) MIC after
amino- guanidine Factor addition MIC Fragrance increase Fragrance
(wt %) (wt %) in potency 1 Olive Leaf 0.625 greater than 2.5 4 2
Lime and Sea 0.625 greater than 2.5 4 3 Lemon Mint 0.0390625 1.25
32 4 Eucalyptus Mint 0.625 2.5 4 (tub/tile) 5 Eucalyptus Mint
0.3125 2.5 8 6 Clementine (Dish) 0.3125 greater than 2.5 8 7 Pink
Grapefruit 0.3125 greater than 2.5 8 8 Wisteria 0.0390625 2.5 64 9
French Lavender 2.5 2.5 1 10 Lavender Cedar 0.625 2.5 4 11 Fresh
Air 0.625 greater than 2.5 4 12 Waterfall 0.15625 greater than 2.5
16 13 Toasted Vanilla 1.25 2.5 2 14 Mandarin Mango 1.25 greater
than 2.5 2 15 Ginger Mango 4x 2.625 2.5 4 16 Beach Sage 4x 2.5
greater than 2.5 1 17 Parsley and Thyme 0.625 2.5 4 18 Mint 1.25
2.5 2 19 Almond 0.15625 2.5 16 20 Almond WF 0.073175 2.5 32
* * * * *