This paper investigates differences in efficacy of isolating pathogenic bacteria Salmonella Enteritidis, Listeria monocytogenes and Escherichia coli O157:H7 between conventional cultivation (ISO method) and immunomagnetic separation (IMS method) related to the types of dairy products and initial numbers of bacteria. Different milk products (dairy pudding-vanilla or chocolate; a mixture of yoghurt and pudding; solid, liquid and fruit yoghurt; AB culture -with or without fruit; cheese spread) were intentionally contaminated with different numbers (≈10 and ≈30) of live cells of the observed bacteria per mL. The obtained results showed that the classical ISO procedure still represents an equally adequate method for the detection of S. Enteritidis and L. monocytogenes in dairy products as well as the IMS method. However, the ISO method was found to be inefficient for determination of E. coli O157:H7 when the initial contamination was low (≈10 live cells per mL). In such cases, even the IMS method appeared to be inefficient when used for fermented dairy products analysis. Fermented dairy products in contrast to the non-fermented ones, still represent a challenge for the development of routine detection methods, especially for S. Enteritidis, whilst the detection of L. monocytogenes and E. coli O157:H7 has improved by introducing the IMS method. The largest difference in the ability to detect bacteria in dairy product samples with reference to the initial number of bacteria by both methods was in the detection of E. coli O157:H7. The choice of broth (non-selective fluid broth vs. selective fluid broth) did not matter in the in the detection of S. Enteritidis and L. monocytogenes by applying the IMS procedure. However, for the detection of E. coli O157:H7 the application of modified tripton-soya broth with novobiocin (mTSB+Nb) has proved to be superior when compared to using the buffered peptone water (BPW). The presented results may be of importance as a scientific basis for future determination of standard methods related to laboratory detection of pathogens in dairy products.
The aim of the paper was to determine the level of soil contamination with lead and perform risk assessment by calculating the Hazard Quotient Index (HQI). The research was carried out during 2015 and 2016 at three locations in Herzegovina (Mostar, Čapljina, and Stolac), where nectarine cultivars ('Big Top' and 'Caldesi 2000') were cultivated. At the Mostar and Čapljina locations, the total content of lead in the soil exceeded MPC values in both years of research. Estimated daily intake (EDI) and estimated weekly intake (EWI) values of lead in the studied nectarine varieties showed no acute or chronic risk for human health.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.