the present invention utilizes propionic acid and / or salts thereof in compositions and methods of fungal inhibition and eradication . in certain embodiments of the present invention , the compositions and methods disclosed herein are directed toward imparting fungal resistance to construction materials . in certain such embodiments , a concentration of greater than 0 . 0 % and less than 5 . 0 % of calcium propionate ( or the equivalent value of propionic acid ) is in the compositions of the present invention . in still other embodiments of the compositions of the present invention , the concentration of propionic acid ( or equivalent chemical value thereof ) can range from 0 . 5 % to 3 . 0 %, or from 1 . 0 % to 2 . 5 %. the propionate compound concentrations described above are capable of providing a benign but effective fungicide as described herein . in certain embodiments , the compositions of the present invention further include a dual cationic component . the dual cationic component of the present invention includes : wherein said quaternary ammonium compound (“ quat ”) is selected from the group consisting of n - alkyldimethyl benzyl ammonium saccharinate ; 1 , 3 5 5 - triazine - 1 , 3 , 5 ( 2h , 4h , 6h )- triethanol ; 1 - decanaminium , n - decyl - n , n - dimethyl -, chloride ( or ) didecyl dimethyl ammonium chloride ; 2 -( 2 -( p -( diisobutyl ) cresosxy ) ethoxy ) ethyl dimethyl benzyl ammonium chloride ; 2 -( 2 -( p -( diisobutyl ) phenoxy ) ethoxy ) ethyl dimethyl benzyl ammonium chloride ; alkyl 1 or 3 benzyl - 1 -( 2 - hydroxyethyl )- 2 - imidazolinium chloride ; alkyl bis ( 2 - hydroxyethyl ) benzyl ammonium chloride ; alkyl demethyl benzyl ammonium chloride ; alkyl dimethyl 3 , 4 - dichlorobenzyl ammonium chloride ( 100 % c12 ); alkyl dimethyl 3 , 4 - dichlorobenzyl ammonium chloride ( 50 % c14 , 40 % c12 , 10 % c16 ); alkyl dimethyl 3 , 4 - dichlorobenzyl ammonium chloride ( 55 % c14 , 23 % c12 , 20 % c16 ); alkyl dimethyl benzyl ammonium chloride ; alkyl dimethyl benzyl ammonium chloride ( 100 % c14 ); alkyl dimethyl benzyl ammonium chloride ( 100 % c16 ); alkyl dimethyl benzyl ammonium chloride ( 41 % c14 , 28 % c12 ); alkyl dimethyl benzyl ammonium chloride ( 47 % c12 , 18 % c14 ); alkyl dimethyl benzyl ammonium chloride ( 55 % c16 , 20 % c14 ); alkyl dimethyl benzyl ammonium chloride ( 58 % c14 , 28 % c16 ); alkyl dimethyl benzyl ammonium chloride ( 60 % c14 , 25 % c12 ); alkyl dimethyl benzyl ammonium chloride ( 61 % c11 , 23 % c14 ); alkyl dimethyl benzyl ammonium chloride ( 61 % c12 , 23 % c14 ); alkyl dimethyl benzyl ammonium chloride ( 65 % c12 , 25 % c14 ); alkyl dimethyl benzyl ammonium chloride ( 67 % c12 , 24 % c14 ); alkyl dimethyl benzyl ammonium chloride ( 67 % c12 , 25 % c14 ); alkyl dimethyl benzyl ammonium chloride ( 90 % c14 , 5 % c12 ); alkyl dimethyl benzyl ammonium chloride ( 93 % c14 , 4 % c 12 ); alkyl dimethyl benzyl ammonium chloride ( 95 % c16 , 5 % c18 ); alkyl dimethyl benzyl ammonium chloride ( and ) didecyl dimethyl ammonium chloride ; alkyl dimethyl benzyl ammonium chloride ( as in fatty acids ); alkyl dimethyl benzyl ammonium chloride ( c12 - c16 ); alkyl dimethyl benzyl ammonium chloride ( c12 - c18 ); alkyl dimethyl benzyl and dialkyl dimethyl ammonium chloride ; alkyl dimethyl dimethylbenzyl ammonium chloride ; alkyl dimethyl ethyl ammonium bromide ( 90 % c14 , 5 % c16 , 5 % c12 ); alkyl dimemyl ethyl ammonium bromide ( mixed alkyl and alkenyl groups as in the fatty acids of soybean oil ); alkyl dimethyl ethylbenzyl ammonium chloride ; alkyl dimethyl ethylbenzyl ammonium chloride ( 60 % c14 ); alkyl dimethyl isopropylbenzyl ammonium chloride ( 50 % c12 , 30 % c14 , 17 % c16 , 3 % c18 ); alkyl trimethyl ammonium chloride ( 58 % c18 , 40 % c16 , 1 % c14 , 1 % c12 ); alkyl trimethyl ammonium chloride ( 90 % c18 , 10 % c16 ); alkyldunethyl ( ethylbenzyl ) ammonium chloride ( c12 - 18 ); di -( c8 - 10 )- alkyl dimethyl ammonium chlorides ; dialkyl dimethyl ammonium chloride ; dialkyl dimethyl ammonium chloride ; dialkyl dimethyl ammonium chloride ; dialkyl methyl benzyl ammonium chloride ; didecyl dimethyl ammonium chloride ; diisodecyl dimethyl ammonium chloride ; dioctyl dimethyl ammonium chloride ; dodecyl bis ( 2 - hydroxyethyl ) ocryl hydrogen ammonium chloride ; dodecyl dimethyl benzyl ammonium , chloride ; dodecylcarbamoyl methyl dimethyl benzyl ammonium chloride ; heptadecyl hydroxyethylimidazolinium chloride ; hexahydro - 1 , 3 , 5 - thris ( 2 - hydroxyethyl )- s - triazine ; myristalkonium chloride ( and ) quat rnium 14 ; n , n - dimethyl - 2 - hydroxypropylammonium chloride polymer ; n - alkyl dimethyl benzyl ammonium chloride ; n - alkyl dimethyl ethylbenzyl ammonium chloride ; n - tetradecyl dimethyl benzyl ammonium chloride monohydrate ; octyl decyl dimethyl ammonium chloride ; octyl dodecyl dimethyl ammonium chloride ; octylphenoxyethoxyethyl dimethyl benzyl ammonium chloride ; oxydiethylenebis ( alkyl dimethyl ammonium chloride ); quaternary ammonium compounds , dicoco alkyldimethyl , chloride ; trimethoxysilyl propyl dimethyl octadecyl ammonium chloride ; trimethoxysilyl quats , and trimethyl dodecylbenzyl ammonium chloride . in some of these embodiments , the dual cationic component is maquat ™ 2525 m 50 % ( mason chemical company hereinafter “ maquat ”) at a concentration ranging from greater than 0 . 0 % to 5 % weight per weight . maquat is comprised of two quaternary ammonium compounds in equal weight to total composition of matter . the two cationic surfactants in maquat are alkyl dimethyl benzyl ammonium chloride and alkyl dimethyl ethyl benzyl ammonium chloride . both of these cationic surfactants are known to possess limited antimicrobial effects and are classified as disinfectants . certain of these cationic components will readily mix with propionate compounds in solution . for example , 0 . 5 % maquat can be mixed with calcium propionate ( at the concentrations listed above ) to readily admix and provide a stable , clear solution . certain embodiments of the compositions of the present invention are made by adding maquat to water at a concentration of 0 . 5 % total weight . after thorough mixing , calcium propionate is introduced to the solution in the concentration of 2 . 5 % by weight to the original water weight and thoroughly solubilized . the resultant composition is then ready for use as a surface disinfectant with relatively long residual effectiveness as a fungicide , bactericide , and viricide . dual quat blends , such as maquat are known to be a highly effective disinfectant with numerous species of bacteria including enterococcus faecium , escherichia coli , escherichia coli 0157 : h7 , pseudomonas aeruginosa , salmonella cholerasuis , salmonella typhi , listeria monocytogenes , staphylococcus aureus , mycobacterium tuberculosis , methicillin resistant staphylococcus aureus , vancomycin intermediate resistant staphylococcus aureus , and vancomycin resistant enterococcus faecalis . the virucidal effectiveness of the quaternary compounds contained maquat includes hepatitis a , b , and c , hiv - 1 , poliovirus type 1 , canine parvovirus , norwalk virus , human coronavirus , and rabies virus . as a fungicide , an example is trichophyton mentagrophytes ( athlete &# 39 ; s foot fungus ) ( 3m tb quat disinfectant cleaner rtu technical data brochure , september 2005 ). to retard leaching and / or dilution of the solution upon application , a cellulose ether can be added to certain embodiments of the compositions of the present invention to aid in film - forming of the solution on a treated surface . those of skill in the art will recognize that other film - forming agents can be utilized in the present invention , including , but not limited to , guar . in some embodiments , the cellulose ether can be sodium carboxymethylcellulose . the sodium carboxymethylcellulose concentrations in certain such embodiments can range from 0 . 05 % to 0 . 5 % weight per weight . the compositions of the present invention can be applied by immersion of the material to be treated , by surface wiping , by brush , roller , pump spray applicator or pressure sprayer . the material can then be allowed to air dry the treated surfaces . suitable materials for treatment with the compositions and methods of the present invention include , but are not limited to , inanimate surfaces such as walls , floors , ceilings , countertops , and any exposed surface where fungal growth is present , as well as textiles , leather , paper , coatings , paints , caulks , adhesives , sealants and surface contact cleaners . furthermore , certain compounds of the present invention , such as those containing solubilized propionic acid or its solid salts with a dual cationic surfactant mixture , can be incorporated within paints and coatings to provide fungal resistance where said paints or coatings are applied ; or , as an additive to impart fungal resistant properties in said paints or coatings by the consumer at times of application . paper and textiles can furthermore be treated in pulp process and fiber process waters with the compounds of the present invention . in certain such embodiments , propionic acid or its solid salts can be solubilized at a concentration of greater than 0 . 0 % and less than 5 . 0 % in combination with a dual cationic component . propionic acid and its salts are inhibitors of some fungi with effectiveness for a period of approximately six days . in laboratory testing with a variety of methods and standards , each of the components when tested individually did not demonstrate resistance to various fungal species . however , as a combination in the concentrations described , immediate and sustained resistance to all fungi tested was demonstrated beyond the times as stipulated by the protocols of industry standards . a disk diffusion method of determining susceptibility of fungi to maquat 2525m 50 % was developed from the kirby - bauer bactericidal disk diffusion method . the diffusion method assumes the migration of active compounds into a surrounding agar medium ( potato dextrose agar ) to intercept and retard the growth of test inoculum seeded to the agar surface . this method was utilized as a screening method to achieve a rapid means of fungal inhibition after 5 days of incubation . the inoculum was composed of a suspension of fungal spores harvested from one week cultures of atcc # 6205 - chaetomium globosum ; atcc # 6275 - aspergillus niger ; and , atcc # 10690 - aspergillus terreus . once the plates were seeded with inoculum , difco concentration disks ( ¼ ″) were impregnated with a 0 . 5 % solution of maquat 2525m 50 %, allowed to air dry in sterile petri dishes and placed at equidistant locations on each plate . at the end of the five day incubation at 30 ° c ., 5 plates containing four disks each were examined visually and microscopically . no zones of inhibition manifested and on six of the twenty disks viable spores were observed . the specimens were graded as moderately resistant . grading is based on the following scale : ( 1 ) not resistant — confluent growth and surface growth on disks ; ( 2 ) moderately resistant — confluent growth without surface growth on disks ; and ( 3 ) resistant — exhibits a zone of inhibition ( no growth ) surrounding disks with no surface growth or sporulation on disks . concurrent with the maquat disk diffusion testing , exact methods were replicated for testing of calcium propionate . a 2 . 5 % solution of calcium propionate was prepared and the difco disks were impregnated with the solution , allowed to air dry and placed on the plates . at the end of the incubation period , the plates were examined visually and microscopically . all of the disks were occluded with profuse growth and were designated as no resistance . concurrent with the above described testing , a solution of 0 . 5 % maquat and 2 . 5 % calcium propionate was prepared and difco disks were impregnated , allowed to air dry , and placed on the plates . after the incubation period , zones of inhibition were observed around all the disks measuring 12 mm . no growth was detected under microscopic examination . the plates demonstrated the exact effects for a period exceeding six weeks . the specimens were graded fully resistant . concurrent with the above described tests , 0 . 5 % of sodium carboxymethylcellulose was added to impart a solution with film forming properties and to determine if a cross linking agent would have any effects on the present invention . examination of the incubated specimens was conducted and zones of inhibition of 10 mm manifested . no growth was present on any disks and an extended period of incubation exceeding six weeks presented no change in resistance or diminution of the zones of inhibition . the specimens were graded fully resistant . another cationic surfactant was selected to determine if calcium propionate exhibited the same synergistic , enhancing effects of resistance with fungi . a solution was created using 0 . 125 % of cetylpyridinium chloride , equivalent to the concentrations of each of the components in maquat 2525m 50 %. exact protocol was followed and examination of the specimen plates revealed no zone of inhibition surrounding the disks . the specimens were graded moderately resistant . long term protection provided by a preservative mechanism to inhibit fungal growth is best demonstrated by the industry recognized tappi test method t 487 . this method is used to determine the resistance of paper and paperboard to fungal growth in ideally suited controlled conditions of light , temperature , moisture , and food supply . treated 50 mm test coupons of paper are placed on a surface of test agar , flooded with a test inoculum of fungal spores , and incubated to determine fungal resistance . the rating that is provided follows an established protocol to determine the degree of mold growth on a rating scale reported as 1 ) not fungal resistant ; 2 ) moderately fungal resistant ; and 3 ) resistant . challenges of treated porous surfaces , represented by selected samples of untreated paper product specified as whatman filter paper # 4 and paper product specified as whatman filter paper # 4 treated with a solution of fungicides , are exposed to designated fungal suspensions known to cause failure under certain use conditions . the test samples are prepared according to t 487 pm - 99 by aseptically removing pre - sterilized 50 mm paper coupons , previously equilibrated to room temperature , and then placed in a controlled chamber at 28 +/− 1 ° c . ( 82 . 40 f ) and 95 %- 98 % rh . the chamber is fitted with a tray filled with a salt solution to maintain humidity control . the test ensues continuously for 21 days and samples are observed weekly . the panels are rated each week according to the appearance of fungal growth . this series of tests according to the tappi t 487 pm - 99 protocol were conducted with multiple specimens of treated and untreated ( control ) paper substrates with the specified fungal species of aspergillus niger ( atcc # 6275 ), chaetomium globosum ( atcc # 6205 ), and aspergillus terreus ( atcc # 10690 ) suspensions . the suspensions of inoculum were harvested from 14 day potato dextrose agar cultures into sterile water , combining the culture suspensions from each fungal genus and adjusting to concentrations of 10 6 / ml . triplicate substrate samples were then prepared from sheets of cellulose fiber papers ( whatman ) cut into 50 mm squares and steam sterilized . the sterilized paper coupons were immersed in a solution of each challenge solution , allowed to soak for ten minutes , removed and placed into aluminum drying trays in a drying oven for 24 hours at 67 ° c . the test papers were placed onto the surface of prepared agar plates containing mineral - salt agar as outlined in t 487 pm - 99 . two plies of paper were treated as a single test specimen and were directly pipetted with 1 ml of fungal suspension on the surface of each test coupon . the plates were then inverted and placed into humid incubation chambers and incubated at 28 ° c .+/− 1 c for 21 days . observations for growth were conducted on successive weekly schedules as well as verification of test inocula to distinguish contaminants or naturally occurring molds from actual challenge organisms . growth was defined as sporulating , hyphael appearances directly from the paper substrate . the following comparative table depicts the various solutions and resistance results :
a novel composition comprised of a monocarboxylic fatty acid synergistically enhanced with a dual quaternary ammonium compound to provide immediate fungal and sporicidal destruction with long term residual resistance .