Fresh Human Faeces Research Articles

Ovarian development in the blowflies Chrysomyaputoria and C. megacephala on natural diets

Fresh human, chicken and cattle faeces were compared as diets for adult female blowflies Chrysomya megacephala (Fabricius) and C.putoria (Wiedemann) (Diptera: Calliphoridae). As controls, sugar and raw beef liver were used. For females of both species, fresh beef liver was the best of these diets: oogenesis was completed in 10-13 days. Human or chicken faeces facilitated slower oogenesis in 27-48 days. On a diet of cattle faeces, C.putoria females began vitellogenesis only 17 days after emergence, whereas females of C.megacephala remained previtellogenic until the end of the experiment (56 days).

Quantitative determination of methanogenic bacteria in the feces of different mammals

In this research on fresh human, cattle, swine, and rabbit feces, methanogenic bacteria were found in all samples examined, at the following concentrations per gram dry weight: swine, 108; human, 107; cattle, 106; and rabbit, 104. Anaerobic heterotrophic bacteria were found in the following concentrations per gram dry weight: human, 1011; swine, 1011; cattle, 1011; and rabbit, 1010. The total number of O2-intolerant was higher than that of O2-tolerant bacteria: about 10–100 times for methanogenic and 100–1000 times for anaerobic heterotrophic bacteria.

Mutagenic activation of biliary metabolites of benzo(a)pyrene by beta-glucuronidase-positive bacteria in human faeces.

Human faeces hydrolysed synthetic beta-D-glucuronides of both p-nitrophenol and phenolphthalein. The origin of this activity in faeces was localised in the bacterial pellet fraction after centrifugation. Ninety-seven bacterial strains with beta-glucuronidase activity isolated from fresh human faeces were identified as species of Bacteroides, Peptostreptococcus, Fusobacterium, Propionibacterium, Clostridium, Eubacterium and Bifidobacterium. They were classified into two groups according to their activity against two synthetic beta-D-glucuronides. One group hydrolysed p-nitrophenyl glucuronide and phenolphthalein glucuronide to the same extent and the other hydrolysed p-nitrophenyl glucuronide much more strongly than phenolphthalein glucuronide. The bile of rats given benzo(a)pyrene by mouth was tested for mutagenicity in the presence and absence of cell-free extracts of human faeces and bacteria. Extracts of beta-glucuronidase-positive bacteria increased the mutagenicity of metabolites of benzo(a)pyrene, as did faecal extracts, but extracts of beta-glucuronidase-negative bacteria did not. D-Saccharic acid-1,4-lactone inhibited the increase in mutagenicity produced by the faecal extracts and extracts of beta-glucuronidase-positive bacteria except for Peptostreptococcus strains 204 and 952. These results indicate that some intestinal bacteria have beta-glucuronidases heterogenous in substrate specificity and that they may be involved in mutagenicity of benzo(a)pyrene in the intestinal tract.

Isolation and characterization of thirteen intestinal microorganisms capable of 7 alpha-dehydroxylating bile acids.

Thirteen anaerobic bacteria capable of performing the 7 alpha-dehydroxylation of both cholic acid and chenodeoxycholic acid were isolated from human feces and also from sewage. Ten organisms from heat-treated samples were species of Clostridium identical or closely related to the Clostridium bifermentans-C. sordellii group and consisted of four strains elaborating 7 alpha-dehydroxylase alone and six strains capable of catalyzing both 7 alpha-dehydrogenation and 7 alpha-dehydroxylation. The remaining three organisms, recovered from fresh human feces, were gram-positive, nonflagellated, nonsporeforming, anaerobic rods and comprised two distinct species. Strain HD-17, still unidentified, had both activities, but was unique in that it exclusively 7 alpha-dehydroxylated cholic acid while biotransforming chenodeoxycholic acid, preferably though 7 alpha-dehydrogenation. Two unclassified strains, b-8 and c-25, metabolized both acids though 7 alpha-dehydroxylation and 7 alpha-dehydrogenation. Except for strains b-8 and c-25, all of th 7 alpha-dehydroxylating bacteria split the conjugated bile acid series, and hydrolases were detected in cell-free filtrates of early stationary-phase broth cultures.

Faecal coliforms and faecal streptococci in streams in the new guinea highlands

Procedures used to assess faecal water contamination were developed in temperate regions and their applicability to tropical waters has been questioned. This paper reports a detailed study of faecal coliform and faecal streptococci concentrations in the streams of the Saka Valley in the Highlands of New Guinea. The Saka Valley supports large populations of humans and domestic pigs, whose faeces are washed into the streams by surface runoff following rain. Faecal coliforms and faecal streptococci, enumerated by the membrane filtration technique, were found to be excellent indicators of faecal pollution in the New Guinea Highlands. A consideration of faecal coliform to faecal streptococci ratios and other factors, leads to the conclusion that most faecal contamination derives from pigs. All waters investigated, with the exception of spring waters, were grossly contaminated with faecal material and these polluted streams provide the total domestic water needs of the New Guineans. The fluctuations in pollution levels are described and their association with water temperature, rainfall and turbidity is analysed. The interpretation of the water contamination data is made speculative by the lack of information on the coliform and streptococcal flora of fresh pig and human faeces under New Guinea Highlands conditions.

Possible explanations for the inhibitory action of boric acid lactose broth at 43 C on fecal coliform bacteria.

It has been shown (Njoku-Obi and Skinner, 1957) that the most probable number of coliforms and of Escherichia species in human feces is consistently higher when counts are made by dilution extinction methods in standard lactose broth at 35 C than when boric acid lactose broth (Vaughn et al., 1951) at 43 C is used. This is an example of a general phenomenon repeatedly noted in the literature. Another example is the work of Skinner and Brown (1934). When the most probable number of coliforms from fresh human feces was determined by the dilution extinction method, the same sample usually yielded a much higher count of coliforms and of Escherichia species with lactose broth incubated at 37 C than with glucose broth at 46 C according to the original Eijkman method. There have been various theories advanced to explain such phenomena but little or no data which would tenid to substantiate the theories. Actually, in most cases, they are merely postulations or assumptions with no proof whatever. The present paper will attempt to subject some of these postulations to proof with the idea of narrowing down the possibilities to one or two, which can then be investigated themselves.

Possible Explanations for the Inhibitory Action of Boric Acid Lactose Broth at 43 C on Fecal Coliform Bacteria1

It has been shown (Njoku-Obi and Skinner, 1957) that the most probable number of coliforms and of Escherichia species in human feces is consistently higher when counts are made by dilution extinction methods in standard lactose broth at 35 C than when boric acid lactose broth (Vaughn et al., 1951) at 43 C is used. This is an example of a general phenomenon repeatedly noted in the literature. Another example is the work of Skinner and Brown (1934). When the most probable number of coliforms from fresh human feces was determined by the dilution extinction method, the same sample usually yielded a much higher count of coliforms and of Escherichia species with lactose broth incubated at 37 C than with glucose broth at 46 C according to the original Eijkman method. There have been various theories advanced to explain such phenomena but little or no data which would tenid to substantiate the theories. Actually, in most cases, they are merely postulations or assumptions with no proof whatever. The present paper will attempt to subject some of these postulations to proof with the idea of narrowing down the possibilities to one or two, which can then be investigated themselves.

The effect of the respiration of putrid gases upon the growth of guinea pigs

Three years ago Mr. G. T. Palmer and the senior author reported here a series of experiments on human subjects conducted by the New York State Commission on Ventilation which indicated that “there are substances present in the air of an unventilated occupied room (even when its temperature and humidity are controlled) which in some way, and without producing conscious discomfort or detectable physiological symptoms, diminish the appetite for food. A natural assumption would be that odoriferous materials contributed to the stale air by the bodies and clothing of the occupants might produce such an effect upon appetite; and the present study is an attempt to detect a possibly analogous effect of putrid odors of a more intense kind upon the growth of guinea pigs. A galvanized iron box 4 feet wide, 2 feet deep and 3 feet high was constructed and divided into two equal vertical compartments, each holding two standard animal cages and each provided with a separate glass door. Fresh air to the amount of 1.5 cubic feet per minute for each compartment (amounting to 4 liters per minute per animal) was supplied to the box by a small centrifugal fan, the supply to each section of the box being carefully regulated by dampers. On the course of the branch duct leading from the fan to one section was inserted a chamber in which was placed a pan of fresh moist human or dog feces, so as to produce a strong fecal odor in that section of the box. Fifteen different series of tests were conducted with this apparatus during the years 1916, 1917 and 1918, 261 animals in all being used. Young guinea pigs were selected, usually weighing between 150 and 300 grams, and they were kept under the experimental conditions for from 4 to 24 days, being weighed each day.