Isolation & Enumeration of Clostridium Perfringens from the Barren River Above & Below the Effluent of the Bowling Green, Kentucky, Sewage Treatment Plant

• Main Author: Hansen, Michael
• Format: Others
• Published: TopSCHOLAR® 1979
• Subjects: Biology; Life Sciences
• Online Access: https://digitalcommons.wku.edu/theses/2443; https://digitalcommons.wku.edu/cgi/viewcontent.cgi?article=3436&context=theses

Samples from five sites on the Barren River were assayed during a one year period from March 1978 to February 1979 for the presence of Clostridium perfringens. These five sites were chosen in relation to their location to the effluent discharge pipe from the Bowling Green, Kentucky, sewage treatment plant. One collection site was located upstream from the discharge point; one station was directly from the mouth of the pipe; and three were located at intermittent points downstream from the discharge point. When counts on the primary isolation medium, egg yolk-free tryptose-sulfite-cycloserine agar (EYF-TSC agar), were compared for each station, the effluent was shown to have a significantly higher mean CFU/ml (p< 0.05) than the other four stations for sulfite-reducing organisms (46 CFU/ml), C. perfringens (31 CPU/ml) and total aerobic chemoorganotrophs (48,000 CFU/ml). Of the physical-chemical Parameters measured at each station only the mean nitrogennitrate (8.8 mg/L) and phosphate (1.13 mg/L) levels were significantly elevated (P< 0.05) from the EFF as compared to the other four stations. Mean values over the sampling period for dissolved oxygen, pH, air temperature, water temperature, iron and turbidity did not differ significantly (p< 0.05) from station to station. Measurements of river flow rate, river stage and precipitation in the 24 hours preceding sampling were applied uniformly to each of the stations, consequently no variations between the stations were expected or demonstrated. The physical-chemical factors that were statistically associated with, or influenced, the changes seen in the C. perfringens and sulfite-reducing organism counts at the effluent appeared to be nitrate, phosphate and river flow rate. These three factors acted independent of each other in their statistical correlation with the bacterial counts. The other physical-chemical parameters measured had no statistical correlation with the counts. A new presumptive test for the identification of C. Perfrinaens, the reverse CAMP test (RCT), was investigated and demonstrated to be a reliable test procedure. Of the organisms giving a RCT positive test, all were identified as C. perfringens. Alternatively, 97.8% of the organisms giving a RCT negative test were identified as being Clostridium spp. other than C. perfringens. The false positive rate for the test was 0.0% while the false negative rate was 2.2%.