Comparative decay of culturable faecal indicator bacteria, microbial source tracking marker genes, and enteric pathogens in laboratory microcosms that mimic a sub-tropical environment

2021 ◽  
Vol 751 ◽  
pp. 141475
Author(s):  
Warish Ahmed ◽  
Simon Toze ◽  
Cameron Veal ◽  
Paul Fisher ◽  
Qian Zhang ◽  
...  
Keyword(s):  
Microbial Source Tracking ◽  
Enteric Pathogens ◽  
Tropical Environment ◽  
Indicator Bacteria ◽  
Source Tracking ◽  
Marker Genes ◽  
Faecal Indicator Bacteria

scholarly journals Elucidating fecal pollution patterns in alluvial water resources by linking standard fecal indicator bacteria to river connectivity and genetic microbial source tracking

2020 ◽  
Vol 184 ◽  
pp. 116132
Author(s):  
Christina Frick ◽  
Julia Vierheilig ◽  
Theodossia Nadiotis-Tsaka ◽  
Simone Ixenmaier ◽  
Rita Linke ◽  
...  
Keyword(s):  
Water Resources ◽  
Fecal Indicator Bacteria ◽  
Microbial Source Tracking ◽  
Fecal Pollution ◽  
Indicator Bacteria ◽  
Source Tracking ◽  
Fecal Indicator

scholarly journals Bacteroides Microbial Source Tracking Markers Perform Poorly in Predicting Enterobacteriaceae and Enteric Pathogen Contamination of Cow Milk Products and Milk-Containing Infant Food

2022 ◽  
Vol 12 ◽  
Author(s):  
Kevin Tsai ◽  
Vivian Hoffmann ◽  
Sheillah Simiyu ◽  
Oliver Cumming ◽  
Glorie Borsay ◽  
...  
Keyword(s):  
Microbial Source Tracking ◽  
Enteric Pathogen ◽  
Enteric Pathogens ◽  
Cow Milk ◽  
Source Tracking ◽  
Infant Food ◽  
Lower Sensitivity ◽  
Contamination Assessment ◽  
Milk Products ◽  
Infant Foods

Consumption of microbiologically contaminated food is one of the leading causes of diarrheal diseases. Understanding the source of enteric pathogens in food is important to guide effective interventions. Enterobacteriaceae bacterial assays typically used to assess food safety do not shed light on the source. Source-specific Bacteroides microbial source tracking (MST) markers have been proposed as alternative indicators for water fecal contamination assessment but have not been evaluated as an alternative fecal indicator in animal-derived foods. This study tested various milk products collected from vendors in urban Kenyan communities and infant foods made with the milk (n = 394 pairs) using conventional culture methods and TaqMan qPCR for enteric pathogens and human and bovine-sourced MST markers. Detection profiles of various enteric pathogens and Bacteroides MST markers in milk products differed from that of milk-containing infant foods. MST markers were more frequently detected in infant food prepared by caregivers, indicating recent contamination events were more likely to occur during food preparation at home. However, Bacteroides MST markers had lower sensitivity in detecting enteric pathogens in food than traditional Enterobacteriaceae indicators. Bacteroides MST markers tested in this study were not associated with the detection of culturable Salmonella enterica and Shigella sonnei in milk products or milk-containing infant food. The findings show that while Bacteroides MST markers could provide valuable information about how foods become contaminated, they may not be suitable for predicting the origin of the enteric pathogen contamination sources.

scholarly journals Hollow-Fiber Ultrafiltration and PCR Detection of Human-Associated Genetic Markers from Various Types of Surface Water in Florida

2010 ◽  
Vol 76 (12) ◽  
pp. 4116-4117 ◽  
Author(s):  
Stephaney D. Leskinen ◽  
Miriam Brownell ◽  
Daniel V. Lim ◽  
Valerie J. Harwood
Keyword(s):  
Surface Water ◽  
Genetic Markers ◽  
Hollow Fiber ◽  
Membrane Filtration ◽  
Microbial Source Tracking ◽  
Pcr Detection ◽  
Source Tracking ◽  
Marker Genes ◽  
Water Types ◽  
Marker Detection

ABSTRACT Hollow-fiber ultrafiltration (HFUF) and PCR were combined to detect human-associated microbial source tracking marker genes in large volumes of fresh and estuarine Florida water. HFUF allowed marker detection when membrane filtration did not, demonstrating HFUF's ability to facilitate detection of diluted targets by PCR in a variety of water types.

scholarly journals Biotic Interactions and Sunlight Affect Persistence of Fecal Indicator Bacteria and Microbial Source Tracking Genetic Markers in the Upper Mississippi River

2014 ◽  
Vol 80 (13) ◽  
pp. 3952-3961 ◽  
Author(s):  
Asja Korajkic ◽  
Brian R. McMinn ◽  
Orin C. Shanks ◽  
Mano Sivaganesan ◽  
G. Shay Fout ◽  
...  
Keyword(s):  
Genetic Markers ◽  
Mississippi River ◽  
Early Stage ◽  
Fecal Indicator Bacteria ◽  
Biotic Interactions ◽  
Microbial Source Tracking ◽  
Indicator Bacteria ◽  
Source Tracking ◽  
Viral Lysis ◽  
Fecal Indicator

ABSTRACTThe sanitary quality of recreational waters that may be impacted by sewage is assessed by enumerating fecal indicator bacteria (FIB) (Escherichia coliand enterococci); these organisms are found in the gastrointestinal tracts of humans and many other animals, and hence their presence provides no information about the pollution source. Microbial source tracking (MST) methods can discriminate between different pollution sources, providing critical information to water quality managers, but relatively little is known about factors influencing the decay of FIB and MST genetic markers following release into aquatic environments. Anin situmesocosm was deployed at a temperate recreational beach in the Mississippi River to evaluate the effects of ambient sunlight and biotic interactions (predation, competition, and viral lysis) on the decay of culture-based FIB, as well as molecularly based FIB (Entero1a and GenBac3) and human-associated MST genetic markers (HF183 and HumM2) measured by quantitative real-time PCR (qPCR). In general, culturable FIB decayed the fastest, while molecularly based FIB and human-associated genetic markers decayed more slowly. There was a strong correlation between the decay of molecularly based FIB and that of human-associated genetic markers (r2, 0.96 to 0.98;P< 0.0001) but not between culturable FIB and any qPCR measurement. Overall, exposure to ambient sunlight may be an important factor in the early-stage decay dynamics but generally was not after continued exposure (i.e., after 120 h), when biotic interactions tended to be the only/major influential determinant of persistence.

Sign in / Sign up

Export Citation Format

Share Document