Identification of Clostridium spp. derived from a sheep and cattle slaughterhouse by matrix-assisted laser desorption and ionization-time of flight mass spectrometry (MALDI-TOF MS) and 16S rDNA sequencing

Autor(en)
Farzaneh Bakhtiary, Hamid Reza Sayevand, Marlene Remely, Berit Hippe, Alexander Indra, Hedayat Hosseini, Alexander G. Haslberger
Abstrakt

Clostridia are widespread and some of them are serious human pathogens. Identification of Clostridium spp. is important for managing microbiological risks in the food industry. Samples derived from sheep and cattle carcasses from a slaughterhouse in Iran were analyzed by MALDI-TOF MS using direct transfer and extended direct transfer sample preparation methods and 16S rDNA sequencing. MALDI-TOF MS could identify ten species in 224 out of 240 Clostridium isolates. In comparison to the 16S rDNA sequencing, correct identification rate of the Clostridium spp. at the species level by MALDI-TOF MS technique was 93.3%. 16 isolates were not identified by MALDI-TOF MS but 16s rDNA sequencing identified them as C. estertheticum, C. frigidicarnis, and C. gasigenes species. The most frequently identified Clostridium species were: C. sporogenes (13%), C. cadaveris (12.5%), C. cochlearium (12%) and C. perfringens (10%). Extended direct transfer method [2.26 ± 0.18 log (score)] in comparison to direct transfer method [2.15 ± 0.23 log (score)] improved Clostridium spp. identification. Using a cut-off score of 1.7 was sufficient for accurate identification of Clostridium species. MALDI-TOF MS identification scores for Clostridium spp. decreased with longer incubation time. Clostridium species predominantly were isolated from carcasses after skinning and evisceration steps in the slaughterhouse. MALDI-TOF MS could be an accurate way to identify Clostridium species. Moreover, continuous improvement of the database and MALDI-TOF MS instrument enhance its performance in food control laboratories.

Organisation(en)
Department für Ernährungswissenschaften
Externe Organisation(en)
AGES - Österreichische Agentur für Gesundheit und Ernährungssicherheit, Shahid Beheshti University of Medical Sciences (SBMU)
Journal
Journal of Food Science and Technology
Band
55
Seiten
3232-3240
Anzahl der Seiten
9
ISSN
0022-1155
DOI
https://doi.org/10.1007/s13197-018-3255-2
Publikationsdatum
08-2018
Peer-reviewed
Ja
ÖFOS 2012
303002 Bakteriologie
Schlagwörter
ASJC Scopus Sachgebiete
Food Science
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/2ec51d5e-2011-48e7-ab6e-1185df00fb68