ABSTRACT
A simple method for the detoxification of ultrafiltration concentrates of wastewaters for rotavirus assay by the indirect immunofluorescence technique has been developed. Polyacrylamide (Bio-Gel) or dextran (Sephadex G50) beads were mixed with concentrates (0.5 g/10 ml, wt/vol) of wastewaters seeded with simian rotavirus SA11 and allowed to stand for 2 h. The supernatant was decontaminated with antibiotics and then assayed for rotaviruses. Concentrates from raw sewage and treated effluents seeded with SA11 were used to infect MA104 or LLC MK2 cell lines. The concentrates, particularly those from raw sewage and anaerobic waste stabilization ponds, were very toxic to the tissue culture cells. These toxic effects were determined by the detachment and subsequent loss of cells after incubation with concentrates and assay medium for 24 h. They were either completely eliminated or were reduced by greater than 80% after treatment with beads.
Subject(s)
Rotavirus/isolation & purification , Sewage , Waste Disposal, Fluid , Water Microbiology , Animals , Cell Line , Chromatography, Ion Exchange , Rotavirus/growth & development , Ultrafiltration/methodsABSTRACT
A modified membrane-Bovis agar, containing a reduced quantity of sodium azide, for the isolation and enumeration of Streptococcus bovis is described and evaluated. Higher counts, with larger colonies, were obtained from water and sewage samples with this medium than with the original formulation.
Subject(s)
Streptococcus/isolation & purification , Agar , Animals , Animals, Domestic/microbiology , Feces/microbiology , FiltrationABSTRACT
Bifidobacteria were consistently present in the faeces of both man and pigs but only occasionally in the faeces of cattle and sheep, and they were not isolated from faecal samples from other animals; total counts of bifidobacteria were obtained by membrane filtration with YN-17 medium, a modification of Resnick and Levin's YN-6 medium. Mannitol-fermenting strains of bifidobacteria were isolated from both human and animal faeces, but sorbitol-fermenting strains were obtained only from human samples. These sorbitol-fermenting strains were identified as either Bifidobacterium adolescentis or B. breve and their numbers were obtained by membrane filtration of Human Bifid Sorbitol agar (HBSA). Sorbitol-fermenting bifidobacteria are specific indicators of human faecal pollution of waters and wastewaters.
Subject(s)
Bifidobacterium/isolation & purification , Feces/microbiology , Sewage , Water Pollution , Animals , Bifidobacterium/metabolism , Cattle/microbiology , Culture Media , Fermentation , Humans , Sheep/microbiology , Sorbitol/metabolism , Swine/microbiologyABSTRACT
Rhodococcus coprophilus and Clostridium perfringens survived in fresh water samples held at 5, 20, and 30 degrees C for over 17 weeks, whereas Escherichia coli and fecal streptococci disappeared after 5 weeks at all three temperatures. R. coprophilus survived for more than 8 months in sterilized sewage and deionized water at all three temperatures, whereas in normal sewage held at 20 degrees C, the survival time was 12 to 26 weeks. In samples held at 30 degrees C, survival times were shorter, probably because of interbacterial competition or protozoal predation. The results indicate that R. coprophilus may be a useful indicator of the presence of remote fecal pollution of farm animal origin, but not of recent pollution, when enumerated alone in polluted waters or wastewaters.
Subject(s)
Actinomycetales/growth & development , Sewage , Water Microbiology , Clostridium perfringens/growth & development , Escherichia coli/growth & development , Streptococcus/growth & development , Temperature , Time FactorsABSTRACT
Freshwater, sewage, and fecal samples from various sources were examined for Rhodococcus coprophilus, associated actinomycetes, Escherichia coli, and fecal streptococci. Rhodococcus coprophilus was isolated consistently from feces of farm animals, poultry reared in proximity to farm animals, freshwater, and wastewater polluted with animal fecal wastes. It was not isolated from samples of human feces. The ratio of R. coprophilus total actinomycetes was higher in feces from cattle, sheep, ducks, and geese than in specimens from pigs, horses, and fowl. In samples from two freshwater streams polluted by fecal material from farm animals, the ratios of R. copropilus to total actinomycetes were similar to those found in fecal specimens from cattle and sheep. Ratios of fecal coliform to fecal streptococci could not distinguish between fresh human and animal fecal samples and, furthermore, were not reflected in the stream waters polluted by animal fecal material. R. coprophilus has potential in water and dairy bacteriology as a specific indicator organism of fecal pollution due to farm animal wastes.
