ERP Micro December 2019

B astin et al . : J ournal of AOAC I nternational V ol . 101, N o . 5, 2018  1615

Table 2017.10D. Comparative results for the confirmation and identification of Listeria species (non- monocytogenes )  

Candidate Tryptic Soy Agar with Yeast Ref. Tryptic Soy Agar with Yeast X a N b Percent PA c X N Percent PA X N Percent PA X N Percent PA X N Percent PA Candidate Ottaviani and Agosti Agar Candidate Oxford Agar Candidate Rapid’L. mono Agar

Target

Collaborator

Listeria species  (non- monocytogenes )

1 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 2 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 3 12 12 100.0 12 12 100.0 12 12 100.0 12 d 12 100.0 12 d 12 100.0 4 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 5 12 12 100.0 12 12 100.0 12 d 12 100.0 12 12 100.0 12 12 100.0 6 12 e 12 100.0 12 12 100.0 12 d 12 100.0 12 12 100.0 12 f 12 100.0 7 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 12 f 12 100.0 8 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 9 12 12 100.0 12 12 100.0 0 0 g 100.0 12 12 100.0 12 e 12 100.0 10 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 12 e 12 100.0 11 12 12 100.0 12 12 100.0 12 d 12 100.0 12 d 12 100.0 12 h 12 100.0 12 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 13 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 14 12 e 12 100.0 12 e 12 100.0 0 0 g 100.0 10 10 i 100.0 12 h 12 100.0 15 12 12 100.0 12 12 100.0 12 12 100.0 12 12 100.0 12 e 12 100.0 16 12 12 100.0 12 12 100.0 12 12 100.0 12 d 12 100.0 12 f 12 100.0

a

X=Total number of isolates tested.

b N=Number of correct identifications. c PA=Positive agreement. d Collaborator confirmed 11 isolates to the species level and 1 isolate to the genus level. e Collaborator confirmed nine isolates to the species level and three isolates to the genus level. f Collaborator confirmed four isolates to the species level and eight to the genus level. g Collaborator did not receive OXA. h Collaborator confirmed eight isolates to the species level and two isolates to the genus level. i Collaborator observed no growth for two isolates and confirmed nine isolates to the species level and one isolate to the genus level.

the safety instructions for future reference. To reduce the risks associated with exposure to chemicals and biohazards, perform pathogen testing in a properly equipped laboratory under the control of trained personnel. Always follow standard laboratory safety practices, including wearing appropriate protective apparel and eye protection while handling chemicals, reagents, and contaminated samples. Avoid contact with the isolates and reagents. Dispose of isolates, chemicals, and reagents according to current industry standards. The Bruker MALDI Biotyper can detect biosafety level 2/3 organisms. Biological samples have the potential to transmit infectious diseases. Follow all applicable local, state/provincial, and/or national regulations on disposal of biological wastes. Wear appropriate protective equipment, which includes but is not limited to protective eyewear, face shield, clothing/lab coat, and gloves. All work should be conducted in properly equipped facilities utilizing the appropriate safety equipment (e.g., physical containment devices). Individuals should be trained in accordance with applicable regulatory and company/institution requirements before working with potentially infectious materials. The cleaning of the target plates should be conducted in a fume cabinet. L. monocytogenes is of particular concern for pregnant women, the aged, and the infirm. It is recommended that these concerned groups avoid handling this organism.

When testing foodborne bacterial isolates, a risk assessment should be performed for any new tests to determine the safety of the protocols and whether the procedure should be performed in a biological safety cabinet. In addition, the use of chemicals and the need to perform certain steps in a fume hood should also be evaluated. When testing is complete, all materials and media possibly containing pathogens should be decontaminated following current industry standards for the disposal of contaminated waste (i.e., autoclave for 20 min at 120°C). Consult the Safety Data Sheet for additional information and local regulations for disposal. To reduce the risks associated with environmental contamination, follow current industry standards for disposal of contaminated waste. D. General Preparation ( a )  Isolation of organisms for testing .—Organisms for testing must be isolated on one of the recommended media. Please refer to the MALDI Biotyper System Quick Guide for Food Testing (No. 1855438) for a list of recommended isolation media (O&A, OXA, MOX, PALCAM, RLM, and TSA/YE). In the collaborative study, a nonselective agar (TSA/YE, Bio-Rad or equivalent), selective agar (OXA, bioMérieux or equivalent),