Representative facultative anaerobes of the bacterial flora from the intestine of female Ascaris suum were isolated and identified. The number of bacteria in the intestine was approximately 4 X 10(9) per g wet weight of intestine. Seventeen of 19 of the isolated colonies were found to secrete 5-hydroxytryptamine in culture. Holding A. suum in an antibiotic-containing medium did not affect the levels of 5-hydroxytryptamine in the worm, which were 231 +/- 14 ng/g in antibiotic-media as compared to 250 +/- 16 ng/g in control media. This implied that the bacteria may not be contributing to the level of 5-hydroxytryptamine in the tissues of A. suum.
The chicken is an animal of great economic importance and is widely used in the assay of certain vitamins, but little is known about its intestinal flora. The first study of the microbial flora of the chicken's intestinal tract was conducted by Kern (1897). His investigations embraced not only the chicken and other gallinaceous birds, but many of the common wild birds. Other work on the microflora of chickens has been reported by Rahner (1901), King (1905), Gage (1911), Menes and Rochlin (1929), and Emmel (1930). All of these workers agreed that Escherichia coli and Aerobacter aerogenes made up the greatest proportion of the intestinal flora. Other types of microorganisms commonly found in the chicken's intestines by these workers were lactobacilli, micrococci, pseudomonads, bacilli, sarcinae, clostridia (in two instances), and yeasts. Unfortunately, none of these studies was quantitative, and some were not too exact from a qualitative standpoint. The type of dietary carbohydrate has a marked effect on the intestinal flora of animals. Early studies on the subject are well reviewed by Rettger and Cheplin (1921), who presented further evidence concerning the influence of carbohydrate upon the intestinal microflora. Later studies have confirmed and enlarged upon these earlier reports (Evenson, 1947). From the standpoint of vitamin synthesis, the type of carbohydrate in the diet is an important factor. Elvehjem and Krehl (1947) have reviewed this subject, hence an account of specific reports on the role of carbohydrates upon intestinal biosynthesis of vitamins will be unnecessary. Elvehjem and Krehl state, "One might place the carbohydrates in the following decreasing order in their favorable effect on vitamin requirement: dextrin, starch, lactose, glucose, sucrose, although this varies with different vitamins." The work presented in this paper was carried out over a period of six months in connection with a nutritional investigation (Couch et al., 1948) that was performed to determine the effects of different carbohydrates upon the intestinal synthesis of biotin by chickens. The microbiological work had as its objective the determination of the influence of various carbohydrates upon the numbers and kinds of microorganisms in the intestinal tract.
The microbial dynamics associated with granular activated carbon (GAC) in a pilot water treatment plant were investigated over a period of 16 months. Microbial populations were monitored in the influent and effluent waters and on the GAC particles by means of total plate counts and ATP assays. Microbial populations between the influent and effluent waters of the GAC columns generally increased, indicating microbial growth. The dominant genera of microorganisms isolated from interstitial waters and GAC particles were Achromobacter, Acinetobacter, Aeromonas, Alcaligenes, Bacillus, Chromobacterium, Corynebacterium, Micrococcus, Microcyclus, Paracoccus, and Pseudomonas. Coliform bacteria were found in small numbers in the effluents from some of the GAC columns in the later months of the study. Oxidation of influent waters with ozone and maintenance of aerobic conditions on the GAC columns failed to appreciably enhance the microbial growth on GAC. After the enactment of the Safe Drinking Water Act in 1974, the U.S. Environmental Protection Agency, acting under the authority of this legislation, promulgated the National Interim Primary Drinking Water Standards. These standards set maximum contaminant levels for several inorganic elements, organic compounds, organic pesticides, radioactivity, and microbial
One explanation for the stimulus to growth exerted on animals by some chemotherapeutic agents, particularly antibiotics, is that such compounds suppress the microbial formation of toxic substances in the intestine (1-3). The evidence is indirect, being based mainly on the response of intestinal clostridia to antibacterial agents (4), and on the presence of potentially toxic substances such as amines and indole in the large intestine (5). Pure cultures of intestinal microorganisms can produce these compounds in the test tube, but there is no direct evidence to show that important amounts of "toxins" are generated within the intestinal tract. Furthermore, the complicated ecology of the intestinal microflora cannot be reproduced by the study of pure cultures.We are indebted to Metchnikoff (6) for stimulating an intensive interest in intestinal intoxication. He assumed that bacterial action on protein produced harmful amines or "ptomaines" (7) which led to enterotoxemia; hence he concluded that any diet able to reduce putrefactive activities in the large intestine would favor the well being of the host. Early work showing the intestinal production of pressor amines (8-11) supported his concept. However, later reports suggesting that intestinal amines are oxidized rapidly by enzymes (histaminase and monoamine and diamine oxidases) in the intestinal mucosa and other tissues (12) have cast doubt on the theory. The matter is not yet settled. Mellanby (13) on the one hand reported negligible absorption of amines from the large intestine, while other studies (14, 15) have indicated that significant amounts can be absorbed. Several workers have noted that young rats and human infants possess distinctly lower amine oxidase activity in their tissues than do adults (16-21) which suggests a predisposition in the young to toxemia from amines. Possibly this accounts for the growth promoting effect of antibacterial agents when fed to young animals (22).A number of amino acid-decarboxylating bacteria (EsdtericMa coU, Streptococcus faecalis, Cloaridium spp., Lactobacillus spp., Proteus vulgaris) are known to flourish in the large intestine and produce amines from arginine, omithine, *
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.