Quantification transfer rates of foodborne pathogens and its optimal conditions using propidium monoazide - quantitative polymerase chain reaction (PMA-qPCR)
學生姓名:
陳字雲
指導教授:
蕭心怡
學期:
111下
摘 要:
The aim of this report was to review the current research on determining biofilm transfer scenarios on food contact surfaces and optimization of PMA-qPCR options to exclude DNA from dead cells in food processing environments. The presence E. coli and L. monocytogenes was evaluated using scanning electron microscopy (SEM), confocal laser scanning method (CLSM), PMA-qPCR, microbial analysis test. With the quantification of biofilm transfer was enumerated by using transfer rates (%) and typical logistic model could be used to describe the transfer of biofilm cells as parameters by using root mean square error (RMSE) values, and adjusted coefficients of determination (R2adj). The results of this review shows that (i) higher attachment of mature L. monocytogenes ST9 and ST87 biofilm (p < 0.05) compared to adhesion and dispersion stages; (ii) The transmission of L. monocytogenes ST9 and ST87 (RMSE: <0.31, and R2adj: 0.84 – 0.95) biofilm was successful transferred at various biofilm stages; (iii) PMA-qPCR exposure of 650 W intensity with 50 𝜇𝑀 of PMA for 15 min demonstrated a better detection than 500 W ; (iv) Long amplicons (1561 bp) were found to be more specific in PMA-qPCR detection than short amplicons (199 bp). In conclusion, PMA-qPCR (650 W, 50 𝜇𝑀 of PMA for 15 min combined with long amplicons) proved effective in distinguishing viable and dead cells as well as quantification of E. coli and L. monocytogenes biofilms in food contact surface and food processing industry. This information could be used to detect the presence of microbiological risk assessment in food contact surfaces and food processing environment.
11132055-摘要20230329-陳字雲(final).pdf