Applicability of universal Bacteroidales genetic marker for microbial monitoring of drinking water sources in comparison to conventional indicators

Abstract

Water quality monitoring is essential for the provision of safe drinking water. In this study, we compared a selection of fecal indicators with universal Bacteroidales genetic marker to identify fecal pollution of a variety of drinking water sources. A total of 60 samples were collected from water sources. The microbiological parameters included total coliforms, fecal coliforms, Escherichia coli and fecal streptococci as the fecal indicator bacteria (FIB), Clostridium perfringens and H2S bacteria as alternative indicators, universal Bacteroidales genetic marker as a promising alternative fecal indicator, and Salmonella spp., Shigella spp., and E. coli O157 as pathogenic bacteria. From 60 samples analyzed, Bacteroidales was the most frequently detected indicator followed by total coliforms. However, the Bacteroidales assay failed to detect the marker in nine samples positive for FIB and other alternative indicators. The results of our study showed that the absence of Bacteroidales is not necessarily an evidence of fecal and pathogenic bacteria absence and may be unable to ensure the safety of the water. Further research, however, is required for a better understanding of the use of a Bacteroidales genetic marker as an indicator in water quality monitoring programs.

Feasibility study of using various types of microorganisms for assessing microbial growth in drinking water distribution systems

“…Moreover, it was observed that a signi cant difference existed between clostridium perfringens and fecal coliform and fungi. A similar result was seen between total coliform and clostridium perfringens and fungal species (Mhlongo et al, 2019;Mirshekar et al, 2019;Shahryari, Nikaeen, Khiadani, et al, 2014). Of course, it is important to note that false-positive and false-negative results were seen between measured microorganisms.…”

“…The positive sample was subcultured anaerobically on Tryptose Sulphite Cycloserine (TSC) agar and formation of colonies of yellow-brown, grey or black on TSC was reported as positive. The con rmed test was then performed using gram staining, motility and nitrate reduction (Shahryari, Nikaeen, Khiadani, et al, 2014). The numbers of total and fecal coliforms, fecal streptococci and Clostridium perfringens were counted using a 10.0-tube table as the Most Probable Number (MPN) per 100.0 ml (APHA, 2017).…”

“…Basically, fecal coliforms and Escherichia coli are used to determine the microbial quality of drinking water (Ashbolt, Grabow, & Snozzi, 2001). Nonetheless, there are a number of research indicating that these two organisms could not be su cient alone for assessing microbial safety and healthy risks (Figueras, 2010;Raeisi et al, 2017;Shahryari, Nikaeen, Khiadani, et al, 2014). For this reason, it is recommended to use the other indicator microorganisms for achieving accurate data microbiological characteristics of consumed water in DWDS.…”

The Adhesion and Spoilage of Shewanella putrefaciens in Tilapia

“…HC-71 and JR-18 with a high adhesion ability were close, located between the positive axis of PC1 and the negative axis of PC2; HR-15 was located between the positive axis of PC1 and PC2; while the similarity of con0 and con6 in the control group were close, indicating that the addition of S. putrefaciens significantly affected the flora composition and had a certain relationship with the adhesion ability of the strains. Bacteroidales, a common pathogen of fish [21]. On day 6 of storage, the differential bacteria in the control group changed into Lactococcus and Acidisphaera.…”

“…Cetobacterium is a common bacterium in fish. Barnesiellaceae mostly comes from water pollution including Bacteroidales, a common pathogen of fish [21]. On day 6 of storage, the differential bacteria in the control group changed into Lactococcus and Acidisphaera.…”