Hawkeye-Jensen, Inc. 4408-B Pottsville Pike Reading, Pennsylvania 19605 (610) 921-5955
TEST:
24-hour reduction test
TEST ORGANISMS:
Esherichia Coli ATCC 13047
Pseudomonas Aeruginose ATCC 27853
Staphylococcus Aurous ATCC 6538
Candida Albicans ATCC 14053
Aspergillus niger ATCC 16404
OBJECTIVE:
To determine if any of the above test samples has the ability to be substantially detrimental to a significant population of known organisms.
PROCEDURE:
Twenty milliliters (ml) of sample were transferred to each of five sterile, capped sample cups. Each cup was inoculated with a calculated inoculum of approximately 1 x 10 of each of the given microbial suspensions and mixed. Samples were taken and plated at 24 hours after inoculation.
RESULTS:
| 3ppm | 10ppm | 20ppm | 1.0% Germaben II | |
| E.Coli | 130 | <10 | 50 | <10 |
| Aeruginosa | 50 | <10 | 10 | <10 |
| Staph.Aureus | 4,000 | 750 | 370 | 2,000 |
| C.Albicans | 50 | 80 | 70 | <10 |
HOW TO READ THIS LAB TEST:
The results show and compare how much each test organism was reduced in each product (3,10, 20 and 1.0%) in a 24-hour period.
Starting with approximately a 750,000 population of each organism, the 3ppm reduced the E.Coli 130 times, the l0ppm less than ten times, the 20ppm 50 times and the 1.0% Germaben II less than 10.
Test Organisms:
| Group | Organisms Used | |
| Ferm. Gram-neg | Enterbacter Cloacae Eacherichia Coli |
ATCC 13047 ATCC11775 |
| Non-form.Gram-negs | Pseudomonas Aeruginosa Burkholderia Cepacia |
ATCC 27853 ATCC25415 |
| Gram Pos. Cocci | Staphylococcus Aureus | ATCC 6538 |
| Yeasts | Candida Albicans | ATCC 14053 |
| Molds | Aspergillus Niger | ATCC 18404 |
Culture Maintenance:
| Culture | Maintenance Agar | Storage | Transfer Options |
| Bacteria | Trypticase Soy | Refrigeration | Monthly |
| Yeasts | Bactrol Disks | Refrigeration | As needed |
| Molds | Sabouraud Dextrose | Refrigeration | Monthly |
Diluents/Recovery,Media
| Diluents | Agars |
| Lotheen broth | Lotheen agar (bacteria, yeasts) |
| Sabouraud Dextrose (molds) |
Inoculum Preps:
| Culture | Incubation |
| Bactaris | 30-35 C/24-48 hrs. |
| Yeasts | same |
| Molds | 20-25 C/7-14 days |
Procedure:
1. At least 20 g of product is inoculated with microbial suspension, so as to give 10 bacteria or 10 yeasts or molds per gram of product.
2. Using minimum sample size of 1 g. prepare decimal dilutions, and determine plate count/g of sample, by pour or surface plating methods.
3. Read plates after 2-3 days @ 30-35 C (bacteria/yeasts), and 3-7 days @ 20-25 C (molds).
4. Resample @ 1,2,3,7,14,28 days at ambient temp.
5. Rechallenge if specified.
Interpretation:
At least 99.9% reduction (veg. Bacteria)/90.0% reduction (molds) within 7 days. Ref: CTFA 1993 Sect. 13 pp 1-2
Challenge testing for the Burn Cream with Colloidal silver was begun on 10/22/97 for the yeast and bacteria groups (excluding Gram positive, which has not been started). And 10/30/97 for the mold group.
The yeast on bacteria groups were reduced 99.99% by day 1 and continued through day 7. The mold had a lesser percent reduction on day one however further testing must be done to make substantial claim.