Fuji Chemical : Inorganic Silver Antimicrobial Effective against E.Coli O-111
Fuji Chemical (Nishi-Ku , Osaka) has confirmed that its inorganic silver antimicrobial “Bactikiller” is effective against infectious E.Coli O-111. In antimicrobial testing conducted by the Food Analysis Center of Japan , in which a plate containing 0.5% Bactikiller glass type was inoculated with a liquid containing O-111 , a result of “not detected” after 24 hours was obtained. This is the first time effectiveness against O-111 has been confirmed in this country. The company will use the claim of effectiveness against O-111 to increase sales.
Food poisoning by O-111has become a public problem because of such events as the fatal incidents in April at a barbeque chain.
The testing was congruent with the JIS Z 2801 test of Antimicrobial efficacy. The target bacterium was “O-111 :HNM”. After inoculation with the test liquid the plate is covered with a film to assure intimate contact with the bacterium and is incubated for 24 hrs at 35 oC and 90% RH. The inoculants is rinsed off and the number of living cells per square centimeter is counted.
The sample consisted of 3 plates treated with Bactikiller and 3 untreated plates. On the untreated plates the bacteria had increased to counts of 360,000 to 420,000 ; while for each of the Bactikiller- treated plates bacteria were not detected (below minimum level of the detection). In this test “Antimicrobial Efficacy” is defined to require a minimum antimicrobial activity level of 2.0 ; in this case the very high activity level of 5.7 was proven
The results of other tests conducted simultaneously also confirmed antimicrobial efficacy against O-111. Viewing the silver component to be working effectively. Fuji says there is strong likelihood of antimicrobial effectiveness against other strains of E.Coli. As an antimicrobial products additive Bactikiller is penetrating markets such as kitchen cutting boards and other household products , flooring materials , and films for wrapping meat. The company expected this proof of effectiveness against O-111 to provide the opportunity to increase sales.