No abstract

A system utilizing the polymerase chain reaction (PCR), the BAXTM, was compared and validated against standard selective/enrichment assays to detect the presence of Salmonella spp. in artificially contaminated samples of raw materials and cosmetic/pharmaceutical products. After a 24 h incubation in lactose broth or lactose broth with Tween 20, the inoculated samples were analyzed both by the BAXTM system and by standard enrichment/selective methods. Standard enrichment assays required 5–7 days to confirm the presence and identification of Salmonella typhimurium, while the BAXTM system reduced the detection time to 30 h. The BAXTM system allowed a faster quality control evaluation of those raw materials and cosmetic/pharmaceutical formulations that require Salmonella spp. screening.

A PCR‐based assay using a one step sample preparation was developed and validated against standard methods for the rapid detection of Aspergillus niger contamination in cosmetic/pharmaceutical raw materials and finished products. Artificially contaminated samples were added to Sabouraud Dextrose Broth (SDB) with 10% Tween 20 and 3% Soy Lecithin. Samples were then agitated at 200 revolutions per minute for 24 h at 35C. Prior to the PCR assay, sample preparation consisted of adding 10 μL of the 24 h enrichment broth sample mixture to a lysis buffer containing Tris‐EDTA and 0.4% SDS. DNA extraction was accomplished by boiling for 1 h to release the mycelial DNA. After DNA extraction, a 50 μL aliquot of the lysate was then added to a PCR tube containing the following ingredients: 4 Ready‐To‐Go PCR beads, 2 μL of two fungal primers, and 48 μL of sterile water. The DNA primers encoded for specific sequences of the Aspergillus spp. 18S rRNA gene. A 363 bp DNA fragment was detected in all of the artificially contaminated samples. Standard methods require 6–8 days to complete the isolation and identification of mold contamination. However, the PCR‐based assay was completed within 27–30 h. Rapid detection of mold contamination in cosmetic/pharmaceutical raw materials and finished products can be used to optimize the quality evaluation of a sample to allow the release in 27–30 h.

There are conflicting reports on whether antibacterial hand hygiene products are more effective than nonantibacterial products in reducing bacteria on hands and preventing disease. This research used new laboratory data, together with simulation techniques, to compare the ability of nonantibacterial and antibacterial products to reduce shigellosis risk. One hundred sixtythree subjects were used to compare five different hand treatments: two nonantibacterial products and three antibacterial products, i.e., 0.46% triclosan, 4% chlorhexidine gluconate, or 62% ethyl alcohol. Hands were inoculated with 5.5 to 6 log CFU Shigella; the simulated food handlers then washed their hands with one of the five products before handling melon balls. Each simulation scenario represented an event in which 100 people would be exposed to Shigella from melon balls that had been handled by food workers with Shigella on their hands. Analysis of experimental data showed that the two nonantibacterial treatments produced about a 2-log reduction on hands. The three antibacterial treatments showed log reductions greater than 3 but less than 4 on hands. All three antibacterial treatments resulted in statistically significantly lower concentration on the melon balls relative to the nonantibacterial treatments. A simulation that assumed 1 million Shigella bacteria on the hands and the use of a nonantibacterial treatment predicted that 50 to 60 cases of shigellosis would result (of 100 exposed). Each of the antibacterial treatments was predicted to result in an appreciable number of simulations for which the number of illness cases would be 0, with the most common number of illness cases being 5 (of 100 exposed). These effects maintained statistical significance from 10(6) Shigella per hand down to as low as 100 Shigella per hand, with some evidence to support lower levels. This quantitative microbial risk assessment shows that antibacterial hand treatments can significantly reduce Shigella risk.

The Celsis ATP Bioluminescence method was optimized and validated to detect the presence of microbial contamination in High Fluoride and Triclosan dentifrice formulations. Several enrichment broths were evaluated by using a 24–27 h incubation period. The ATP concentrations of the enrichment broths were found to a range from 0.012 to 0.040 nM. None of the tested enrichment broths were found to exhibit any sample inhibition/enhancement effects on the ATP Bioluminescence reaction. Dentifrice suspensions were inoculated with bacteria, yeast, and mold. All test microorganisms (ca. 1–15 CFU/g) were detected within a 24–27 h incubation period by using TAT Broth Base enrichment broths containing different concentrations of the following ingredients: Tween 20, Neopeptone, Dextrose, Triton X‐100, Thiosulfate, Sodium Dibasic Phosphate, and Glycine. Negative ATP response after 24–27 h of incubation at 35C indicates the absence of contamination from these products.