ACTION OF INTESTINAL MICROORGANISMS ON ASCORBIC ACID' respond to a diet rich in vitamin C; however, upon intramuscular injection of
|
|
- Stella Knight
- 5 years ago
- Views:
Transcription
1 ACTION OF INTESTINAL MICROORGANISMS ON ASCORBIC ACID' RAYMOND M. YOUNG AND L. H. JAMES Department of Bacteriology, University of Maryland, College Park, Maryland Received for publication, July 26, 1941 EFFECT OF PURE AND MIXED BACTERIAL CULTURES ON ASCORBIC ACID Marin (1936) described a clinical case of hemorrhagic scurvy which did not respond to a diet rich in vitamin C; however, upon intramuscular injection of a solution of the vitamin, the patient recovered rapidly. Hetenyi (1935) gave patients suffering from colitis gravis and exhibiting avitaminosis daily intravenous injections of 150 mg. of ascorbic acid; recovery was complete in several cases. The failure of response to a diet rich in vitamin C and the positive effects of intramuscular and intravenous injections of this substance suggest bacterial destruction of ascorbic acid in the gastro-intestinal tract before absorption can take place. The possibility of microbial decomposition of the vitamin has not been overlooked. Stepp and Schroder (1935) found a strain of Escherichia coli that decomposed ascorbic acid, and Kendall and Chinn (1939) reported the isolation of members of the Mucosus capsulatus and Enterococcus groups which fermented the vitamin. Kendall and Chinn showed that bacterial decomposition of this substance is more a strain than a species characteristic, for some strains in these groups failed to show any destructive effect. A strain of the Mucosus capsulatus group, one of the Flexner bacillus and one of Alcaligenes inhibited atmospheric oxidation of ascorbic acid. Glucose exerted a sparing action on the fermentation of ascorbic acid by intestinal strains of enterococci and members of the Mucosus capsulatus group. Because of the importance of the interrelationship between vitamins, bacterial growth and human nutrition, the present research was undertaken to investigate the influence of several pure and mixed cultures of normal intestinal bacteria on the stability of ascorbic acid, and to study various factors involved in the action. It must be assumed that recognition of vitamin C deficiency resulting from microbic destruction in the gastro-intestinal tract must depend, to some degree at least, upon actual isolation of the agents involved and on chemical proof of the destructive action of ascorbic-acid-fermenting bacteria on the vitamin in artificial medium. EXPERIMENTAL WORK Methods Ascorbic acid nutrient broth was employed. The broth was prepared as follows: a weighed amount of crystalline ascorbic acid was dissolved in a small amount of water, filtered through a Berkefeld filter and the sterile filtrate added to sterile standard nutrient broth, giving a final concentration of A portion of the data submitted by the senior author as a thesis in partial fulfillment of the requirements for the degree of Master of Science. 75
2 76 RAYMOND M. YOUNG AND L. H. JAMES mg per ml of broth. This concentration of ascorbic acid was decided upon after consideration of the results of preliminary studies, in which it was observed that ascorbic acid in a concentration as low as 0.01 per cent at times would be completely oxidized by atmospheric oxygen before the bacteria had multiplied sufficiently to attack the vitamin. On the other hand, concentrations of ascorbic acid above 0.14 per cent definitely inhibited growth of the intestinal bacteria. Thus it was considered undesirable to use either very high or low concentrations of the vitamin. Under the conditions existing in the intestinal tract ascorbic acid is present only in relatively small amounts. If it could be demonstrated that intestinal bacteria are capable of oxidizing ascorbic acid in amounts several times the concentration commonly found in the intestinal contents, the evidence for microbial decomposition of vitamin C would be more conclusive. When carbohydrates were used in the medium they were present in a final concentration of 1 per cent, unless indicated otherwise in this paper. The ph for the mediums used was adjusted to Preliminary experiments indicated no significant acceleration or inhibition of oxidation of vitamin C in uninoculated nutrient broth at several ph values ranging from 3 to 8. After removing an aliquot portion for immediate analysis, the ascorbic acid nutrient broth was distributed in 100 ml. portions in 180 ml. bottles which were inoculated with the various organisms studied. All cultures and an uninoculated control were incubated at 37CC. Titrations were made frequently, using a modified procedure of Tillman's sodium 2,6-dichlorophenolindophenol method described by Bessey and King (1933). Duplicate portions of 1 ml. each were removed from the cultures and control to 150 ml. flasks containing 1 ml. glacial acetic acid in 50 ml. of distilled water. The samples were titrated with freshly standardized s6dium, 2, 6-dichlorophenolindophenol, 1 ml. of which was equivalent to 0.22 mg. of ascorbic acid. The end-point was considered reached when a faint pink coloration appeared and remained foratleast 20 seconds. The titration was completed within two minutes, and all determinations were carried out in duplicate or triplicate. For control purposes, all of the cultures employed were tested for ability to produce a dye-reducing substance in ascorbic-acid-free nutrient medium and glucose broths. In no instance was the presence of such a substance detected. Unless indicated otherwise, a heavy inoculum of 0.5 ml. of an 18-hour-old nutrient broth culture was used in the following studies in order to obtain a large bacterial population in a short time. Under these conditions luxuriant growth was evident in all of the cultures within a few hours. In experiments conducted under anaerobic conditions reduced oxygen tension was obtained by use of a vacuum incubator which provided a 30-inch vacuum. The temperature was adjusted to 370C. and was maintained evenly in all parts of the incubator by means of a pump which circulated heated oil around the sides of the incubator.
3 ACTION OF INTESTINAL NaCRO6RGANISMS ON ASCORBIC ACID 77 ACTION OF PURE CULTURES AND MIXTURES OF ENTERIC NaCRO6RGANISMS UPON ASCORBIC ACID Several pure cultures of the Proteus, Alcaligenes and Escherichia genera were inoculated into ascorbic acid nutrient broth. The Proteus cultures included the following strains: OXK, X-19, X-2 and Iowa. The Alcaligenes strains employed were Alcaligenes fecalis and Alcaligmene fecalis var. Iowa. Three varieties of Escherichia coli were used, communis, communior, and H-52. Under aerobic conditions the three varieties of Escherichia coli employed decomposed the ascorbic acid completely within hours, whereas an uninoculated control contained 63 and 34.4 per cent respectively of the initial amount of vitmin C after the same time intervals. The loss of ascorbic acid in the uninoculated controls was due, we must assuime, to atmospheric oxida- TABLE 1 Action of pure cultures and a mixture of pure cultures of intestinal bacteria upon ascorbic acid in nutrient broth under aerobic conditions CULTURES INCUBATION PERIOD IN HOURS Escherichia coli var. communis * E8cherichia coli var. communior Escherichia coli var H Proteus OXK Proteus X Proteus X Proteus vulgari var. Iowa Alcaligenes fecalis Alcaligeneefecalis var. Iowa Mixtures of the above pure cultures Uninoculated control * Milligrams ascorbic acid per ml. tion. Undoubtedly some atmospheric oxidation of the vitamin occurred in the treated cultures, but this does not affect the interpretation of the results, since the control still contained some vitain C several hours after the vitamin had completely disappeared from the broth cultures of Esche7richia coli (see table 1). Unlike the action of Escherichia coli, Proteus and Alcaligenes organisms did not decompose ascorbic acid but markedly inhibited atmospheric oxidation of the substance. As indicated in table 1, the vitamin was not completely oxidized even after 192 hours in the presence of several species or varieties of Proteus and Alcaligenes, whereas the uninoculated control had lost all of the substance between 32 and 72 hours of incubation. The protective action was quite similar with the species of both genera and was operative even in an alkaline ph of from 7.3 to 7.72.
4 78 RAYMOND M. YOU&G AND L. H. JAMES When the protective Alcaligenes and Proteus organisms were mixed with the ascorbic acid decomposers the protective action was not operative; in a mixture of the nine pure cultures listed in table 1 the ascorbic acid was completely destroyed during 14 hours incubation. Since anaerobic conditions prevail in the intestine of man, it was desirable to determine whether the oxidation of vitamin C by intestinal bacteria is effective in the absence of oxygen. Accordingly, ascorbic acid nutrient broth cultures of Escherichia coli, including the communis and communior varieties and a few strains isolated from human feces, together with a typical fecal strain of Aerobacter aerogenes and a strain of Citrobacter, were incubated under anaerobic conditions. The results presented in table 2 show that vitamin C is oxidized by intestinal strains of bacteria also under anaerobic conditions. The oxidation was completed within 14 hours, with the exception of the Citrobacter strain TABLE 2 Action of pure cultures of intestinal bacteria upon ascorbic acid under anaerobic conditions CULTURES INCUBATION PERIOD IN HOURS Citrobacter * Aerobacter aerogenes var. Y Escherichia coli var. communis Escherichia coli var. communior Escherichia coli (typical strains isolated from human feces) Y S B F A A A Uninoculated control * Milligrams ascorbic acid per ml. which oxidized the vitamin completely within 22 hours. The uninoculated control contained 95.4 per cent of the original amount of vitamin after 14 and 22 hours. Small losses of vitamin C from uninoculated controls held under anaerobic conditions are due to unavoidable exposure of the samples to air during sampling and titration. ACTION OF PURE CU1UURES AND OF MIXTURES OF ENTERIC MICROORGANISMS UPON ASCORBIC ACID IN THE PRESENCE OF FERMENTABLE CARBOHYDRATE This study had the following objectives: (1) to determine if the presence of readily fermentable carbohydrate will prevent the oxidation of vitamin C; (2) to learn if the action is similar under both aerobic and anaerobic conditions; and (3) to observe the effect of varying concentrations of glucose upon the oxidation of the vitamin by Escherichia coli var. communss.
5 ACTION OF INTESTINAL MICROORGANISMS ON ASCORBIC ACID One per cent glucose and lactose broths containing 0.41 mg. of ascorbic acid per ml. were prepared and portions inoculated with the communis, communior,and H-52 varieties of Escherichia coli. Uninoculated controls were run with each carbohydrate broth; a second series of controls was employed consisting of nutrient broth containing 0.41 mg. of ascorbic acid per ml. but no glucose. All test samples were placed under aerobic conditions. The data in table 3 give evidence that both glucose and lactose not only spare vitamin C from bacterial oxidation but also protect the vitamin from atmospheric oxidation in actively growing cultures of Escherichia coli. After 48 hours all of the cultures of Escherichia coli in glucose and lactose broth contained at least 80.5 per cent of the initial amount of the vitamin, while the same cultures which had no glucose or lactose present in the medium lost all of the vitamin within 22 hours. Bacterial destruction of the vitamin is evidenced by the presence of 32.2 per cent of the initial amount in the uninoculated con- TABLE 3 Action of pure cultures of enteric bacteria upon ascorbic acid in nutrient, glucose and lactose broths incubated under aerobic conditions CULTURES NUJTRIETwNT GLUCOSE LACTOSE Hours Escherichia coli var. communis * Escherichia coli var. communior Escherichia coli var. H Uninoculated control * Milligrams ascorbic acid per ml. trol after 22 hours, when the sugar-free cultures of Escherichia coli had lost all of the vitamin. Protection from atmospheric oxidation is observed by comparing the amount of vitamin retained in the lactose and glucose broth cultures of Escherichia coli with the vitamin content of uninoculated controls. The former after 48 hours contained at least 80.5 per cent of the initial amount of vitamin C, while the vitamin in uninoculated controls had been completely oxidized by atmospheric oxygen. If no protection from atmospheric oxidation were offered, the glucose and lactose broth cultures at any momentduringthe incubation would contain the same amount of vitamin C as the uninoculated controls for atmospheric oxidation. Since bacteria grow under anaerobic conditions in the intestine of man, it was desirable to determine whether the carbohydrate-sparing action on vitamin C as observed under aerobic conditions would operate under anaerobic conditions. Accordingly, the experimental conditions used in the previous experiment were duplicated with the exception of placing the cultures under anaerobic 79
6 Of0 RAYMOND M. YOUNG AND L. H. JAMES conditions. The bacterial cultures employed included the communiu, communior and Y-12 varieties of Escherichia coli, Aerobacter aerogenes var. Y-12, and a strain of Citrobacter. The results of these tests indicated that ascorbic acid is spared completely from bacterial oxidation also under anaerobic conditions. No decomposition of the vitamin had occurred in any of the cultures containing glucose or lactose when the experiment was concluded after 144 hours incubation whereas the vitamin in the sugar-free nutrient broth control cultures was completely oxidized within 14 hours. In order to determine the effect of concentration of fermentable sugar upon the sparing of vitamin C, a series of tests were carried out in which ascorbic acid broths with varying concentrations, 1 per cent, 0.1 per cent and 0.03 per cent glucose were employed. Escherichia coli var. communis was used as the test culture, and incubation was carried out under anaerobic conditions. Bacterial counts were made during the growth of the culture to ascertain if ascorbic acid stimulates growth which may be observed by comparing the growth curve of bacteria in the presence of vitamin C with the growth curve of bacteria developing in the same medium without the vitamin. The amount of glucose present was determined with each titration of ascorbic acid, and the quantitative platings. The method used for glucose determination was a micro method especially designed by Stiles, Peterson and Fred (1926) for estimating glucose in bacterial cultures. The results of the tests in which glucose was employed are shown in figures 1, 2 and 3. One per cent and 0.1 per cent concentrations of glucose in the presence of Escherichia coli var. communis spared vitamin C to the extent of 99 per cent of the original amount after 60 hours incubation, while in the sugar-free control inoculated with the same organism ascorbic acid was oxidized completely within 25 hours. After 60 hours incubation, the one per cent glucose broth contained 58 per cent of the initial amount of glucose, while the 0.1 per cent broth retained only 15 per cent of the initial amount of glucose. Glucose in the 0.03 per cent broth was entirely utilized after 43 hours; as is evident in figure 3, sparing of vitamin C was operative until the glucose content began to be depleted. The vitamin was spared to the extent of 97 per cent of the initial amount during the first 24 hours of incubation, while in the sugar-free control it was completely oxidized within this period. However, after the glucose had been utilized the destruction of the vitamin was rapid, being completed at 60 hours incubation. The uninoculated control contained 60 per cent of the vitamin after 60 hours, indicating that the bacteria were responsible for rapid decomposition of ascorbic acid after the sparing action of glucose ended. The effect of ascorbic acid upon growth of Escherichia coli var. communis in varying concentrations of glucose also is represented in figures 1, 2, and 3. It will be not.ed that in general the amounts of bacterial growth in the different concentrations were quite similar and that, although the initial counts in all tubes were alike, approximating 200 organisms per ml., vitamin C definitely inhibited bacterial growth to such an extent that at no time did the growth of bacteria in broths containing the vitamin exceed that of the vitamin-free broths, except near the end (fig. 3).
7 ACTION OF INTESINAL CRO6RGANISMS ON ASCORBIC ACID u U I: 54-2Z 0 J 0 goo 9 80 U 50 C d L.. 20 l go 10 o lr 0 INCtJBATION PENOD IN HOURS FIG. 1. EFFECT OF A 1 PER CENT GLuCOSE BROTH UPON THE SPARING OF ASCORBIC ACID IN THE PRESENCE OF ESCHERICHIA COLI VAR. COMMUNIS A-Vit. C in vitamin-glucose culture; B-Vitamin C in uninoculated control; C-Vitamin C in glucose-free culture; D-Glucose in vitamin-glucose culture; E-Bacterial growth in plain broth; F-Bacterial growth in vitamin-glucose broth. OAn 20 I0 4 S I- -.~~~~~~~~~~~ '.. U ~~~El,f *1 -I ~ ~~~~~~~~~~ J1~~~~~~~~~~ INCUBATION PERIOD IN HOURS FIG. 2. EFFECT OF A 0.1 PER CENT GLuCOSE BROTH UPON TEB SPARING OF ASCORBIC ACID IN THE PRESENCE OF ESCHERICHIA COLI VAR. COMMUNIS A-Vit. C in vitamin-glucose culture; B-Vit. C in uninoculated control; C-Vit. C in glucose-free culture; D-Glucose in vitamin-glucose culture; E-Bacterial growth in plain broth; F-Bacterial growth in vitamin-glucose broth.
8 82 RAYMOND M. YOUNG AND L. H. JAMES These studies concerning the effect of varying concentrations of glucose upon the sparing of vitamin C suggest that ascorbic acid, a carbohydrate, is utilized as a source of carbon when the available supply of fermentable sugar is depleted. ACTION OF FECAL CUIrURES UPON ASCORBIC ACID IN PLAIN NUTRIENT AND IN CARBOHYDRATE-CONTAINiNG BROTHS Having observed that pure stock cultures of Escherichia coli and pure cultures of the same species isolated from human feces were able to decompose vitamin C, an experiment was planned with the purpose of determining if normal intestinal flora of a few individuals would exhibit the same destructive in vitro action. 0.~~~~~~~~~~~~~~~~~~~~~~~~~h O INCUBATINPERIODINHOUS FIG. 3. EFFECT OF A 0.03 PER CENT GLUCOSE BROTH UPON TH SPARING OF ASCORBIC ACID IN THE PRESENCE OF ESCHERICHIA COLI VAR. COMMJNIS A-Vit. C in vitamin-glucose; B-vit. C in uninoculated control; C-vit. C in glucosefree culture-d4glucose in vitamin-glucose culture; Bacterial growth in plain broth; F-Bacterial growth in vitamin-glucose broth. The use of mixed fecal cultures more nearly duplicates microbial conditions in the intestines than the use of isolated pure cultures of predominating types. A small fecal sample from each of four human subjects was added to each of four dilution blanks. The suspensions were well shaken, allowed to settle, and a loop of the suspended microorganisms from each was transferred to nutrient broth and the culture incubated. Mfter luxuriant growth was evident inoculations were made in duplicate into glucose and lactose nutrient broths, each tube containing 0.36 mgm. of ascorbic acid per mi. of broth. Incubation was carried out at 370 under both aerobic and anaerobic conditions. The data obtained indicated that under both aerobic and anaerobic conditions sugar-free cultures from the four fecal specimens oxidized ascorbic acid com-
9 ACTION OF INTESTINAL MICRO6RGANISMS ON ASCORBIC ACID pletely within 24 hours, while after the same period 0.16 mg. of ascorbic acid per ml. of broth remained in an uninoculated control under aerobic conditions, and 0.33 mg. per ml. remained in an uninoculated anaerobic control, indicating again that atmospheric oxygen is not necessary in the oxidation of ascorbic acid by intestinal bacteria. As was observed previously with the pure cultures of ascorbic acid oxidizing bacteria, glucose and lactose in concentrations of 1% completely protected the vitamin from bacterial oxidation under both aerobic and anaerobic conditions. DISCUSSION The outstanding observation from the studies of this investigation is the apparent ease with which ascorbic-acid-fermenting bacteria may be isolated from human feces without having to resort to special selection or acclimatization technique. Strains of E8cherichia coli and Aerobacter aerogenes isolated from the intestinal contents of several human subjects were found to destroy ascorbic acid rapidly in nutrient broth after good growth was evidenced. These findings suggest that symptoms of vitamin C deficiency in certain individuals, in spite of a diet adequate in the vitamin, might be traced to an intestinal flora high in ascorbic-acid-fermenting bacteria. Although the point of absorption of ascorbic acid is not well-known as yet, a possibility that significant loss of the vitamin occurs through overgrowth of ascorbic-acid-fermenting bacteria in the alimentary tract has been suggested by several investigators. Abt and Farmer (1938) reported that the normal individual does not excrete over 6-10 mg. of vitamin C daily, even when large amounts are taken by mouth. Under abnormal conditions (diarrhea and colitis) the amount varied according to number and type of stools. Wilder and Wilbur (1937) reported that variable amounts of vitamin C are lost in the stool or destroyed in the gastro-intestinal tract even under normal conditions. Bacterial fermentation in the stomach commonly proceeds unchecked in achlorhydric patients. Einhauser (1936) reported that conditions of hypoacidity were accompanied in several cases by disturbed absorption and destruction of vitamin C. Since gastro-intestinal catarrh also accompanied the vitamin deficiency symptoms, Einhauser believed that the vitamin was oxidized and destroyed by the gastro-intestinal flora. The hypochlorhydric subjects improved markedly after oral administration of large quantities of lemon juice. The destruction of ascorbic acid by bacteria in the intestine of man cannot be of serious consequence in most people or there would be more extensive evidence of vitamin C deficiency. However, with some individuals who have an intestinal flora high in ascorbic-acid-fermenting microorganisms symptoms of scurvy such as lowered resistance, anemia, internal hemorrhage, pains in the joints, and edema in the extremities may be present and wrongly attributed to another cause; thus the possibility of this factor playing a significant part in Added significance the health of some individuals should not be overlooked. is attached to disorder involving anacidity, since this condition favors growth ascorbic-acid-fermenting bacteria of intestinal bacteria in the stomach; and, if 83
10 84 RAYMOND M. YOUNG AND L. H. JAMES are present much or all of the vitamin may be decomposed before it reaches the absorbing tissues of the intestines. The presence of even small amounts of glucose definitely delays the decomposition of ascorbic acid until the sugar is used up. It seems quite possible that the juices of citrus fruits, which are rich in sugars and are natural sources of vitamin C, would deter microbic attack upon ascorbic acid so long as these sugars are present in the digestive tract. The failure of the oral administration of vitamin C in certain conditions in which parental injection yields positive experimental or clinical results, and the favorable results following its use in extremely large doses when small doses were unavailing present a problem which invites further study. SUMMARY Several direct human fecal cultures and isolated cultures of Escherichia coli and Aerobacter aerogenes were found to decompose vitamin C under both aerobic and anaerobic conditions. Organisms of the Proteus and Alcaligenes groups failed to attack. the vitamin and definitely protected the substance from atmospheric oxidation, but the protective action was not operative in the presence of vitamin-c-decomposing bacteria. The presence of glucose or lactose in ascorbic acid nutrient medium definitely "spared" the vitamin from oxidation by the fecal cultures and pure cultures of Escherichia coli. The sparing action was operative under aerobic and anaerobic conditions. The vitamin disappeared rapidly from the medium as soon as the sugar had been completely utilized. REFERENCES ABT, A. F., AND FARMER, C. J Pharmacology and Therapeutics of Vitamin C. J. Am. Med. Assoc., 111, BESSEY, 0. A., AND KING, C. G The Destruction of Vitamin C in Plant and Animal Tissues and its Determination. J. Biol. Chem., 103, EINHAUSER, M Vitamin C and Gastro-Enteritis. Z. ges. exptl. Med., 98, HETENYI, G Treatment of Colitis Gravis with Ascorbic Acid. Orvosi Hetilap, 79, KENDALL, A. I., AND CHINN, H The Decomposition of Ascorbic Acid by Certain Bacteria. Studies in bacterial metabolism. J. Infectious Diseases, 62, MARIN, P Scurvy from the Intestinal Bacterial Destruction of Vitamin C. Minerva med. II, STEPP, W., AND SCHRODER, H The Fate of Vitamin C in the Intestinal Canal. I. The effect of intestinal bacteria on vitamin C. Klin. Wochschr., 14, STILES, H. R., PETERSON, W. H., AND FRED, E. B A Rapid Method for the Determination of Sugar in Bacterial Cultures. J. Bact., 12, WILDER, R. M., AND WILBUR, D. L Diseases of metabolism and nutrition. Arch. Internal Med., 59,
Consequently, the authors decided to investigate the various A STUDY OF METHODS FOR THE DETERMINATION OF
A STUDY OF METHODS FOR THE DETERMINATION OF REDUCING SUGARS IN BACTERIAL CULTURES COLORIMETRIC METHODS DOROTHEA KLEMME AND CHARLES F. POE Division of Sanitary Chemistry, Department of Chemistry, University
More informationlactose-fermenting variants (reds). Appreciable lactose utilization variants. Hershey and Bronfenbrenner (1936) found the non-lactosefermenting
THE LACTASE ACTIVITY OF ESCHERICHIA COLI- MUTABILE' CHARLES J. DEERE, ANNA DEAN DULANEY AND I. D. MICHELSON Department of Chemistry and Department of Bacteriology, University of Tennessee School of Biological
More informationPreliminary in vitro studies by Young and James (1942) showed that
DECOMPOSITION OF VITAMIN C BY BACTERIA' RAYMOND M. YOUNG A"w LEO F. RETTGER Department of Bacteriology, Yale Univer8ity, New Haven, Connecticut Received for publication May 24, 1943 The decomposition of
More informationNON-LACTOSE FERMENTING BACTERIA FROM. While B. coli is generally accepted as a satisfactory index of
NON-LACTOSE FERMENTING BACTERIA FROM POLLUTED WELLS AND SUB-SOIL' I. J. KLIGLER From the Laboratories of the Rockefeller Institute for Medical Research, New York Received for publication February 1, 1918
More informationvolume and surface area. Walker and Winslow (1932) reported metabolic rates per cell being observed towards the end of the
A COMPARISON OF THE METABOLIC ACTIVITIES OF AEROBACTER AEROGENES, EBERTHELLA TYPHI AND ESCHERICHIA COLI C. E. CLIFTON Department of Bacteriology and Experimental Pathology, Stanford University, California
More informationRICINOLEATE UPON BACTERIA
A COMPARATIVE STUDY OF THE ACTION OF SODIUM RICINOLEATE UPON BACTERIA From the Division of Laboratories and Research, New York State Department of Health, Albany Received for publication, May 14, 1928
More informationESCHERICHIA COLI-MUTABILE1. antiseptics employed "activated" the lactase which was present, "activate" the lactase.
ON THE "ACTIVATION" OF THE LACTASE OF ESCHERICHIA COLI-MUTABILE1 CHARLES J. DEERE Department of Chemistry, University of Tennessee School of Biological Sciences, Memphis Received for publication August
More informationapplied. Therefore, it was thought desirable to study the method
A COMPARISON OF THE EIJKMAN TEST WITH OTHER TESTS FOR DETERMINING ESCHERICHIA COLI IN SEWAGE Bureau of Bacteriology, Maryland State Department of Health, Baltimore, Maryland Received for publication July
More informationSimpson (1928), Julianelle (1937), Thompson and Khorazo. that the pathogenic strains, (Staphylococcus aureus and Staphylococcus
THE RELATION OF AEROBIOSIS TO THE FERMENTATION OF MANNITOL BY STAPHYLOCOCCI EUGENIA VALENTINE COLWELL Laboratory of Industrial Hygiene Inc., New York City Received for publication August 5, 1938 While
More informationpossibilities occurs. It has been found that the organism acquires addition of vitamin B1 to cells of P. pentosaceum which had
ADAPTATION OF THE PROPIONIC-ACID BACTERIA TO VITAMIN B1 SYNTHESIS INCLUDING A METHOD OF ASSAY M. SILVERMAN AND C. H. WERKMAN Bacteriology Section, Industrial Science Research Institute, Iowa State College,
More informationhanging-drop technique. The results are macroscopic. They are Semi-solid media have been employed for many years in the
THE USE OF SEMI-SOLID AGAR FOR THE DETECTION OF BACTERIAL MOTILITY' RALPH P. TITTSLER AND LESLIE A. SANDHOLZER Department of Bacteriology, University of Rochester, School of Medicine and Dentistry, Rochester,
More informationRELATIONSHIP TO RESISTANCE IN KLEBSIELLA PNEUMONIAE
THE SIGNIFICANCE OF LACTOSE FERMENTATION AND ITS RELATIONSHIP TO RESISTANCE IN KLEBSIELLA PNEUMONIAE VICTOR J. CABELLI' AND M. J. PICKETT Department of Bacteriology, University of California, Los Angeles,
More informationStorage of waters, underground, surface, sea and sewage, phenomenon is the more puzzling because the waters in their
RELATION BETWEEN FOOD CONCENTRATION AND SURFACE FOR BACTERIAL GROWTH1 H. HEUKELEKIAN2 AND A. HELLER3 Agricultural Experiment Station, New Brunswick, New Jersey Received for publication April 19, 1940 Storage
More informationBACTERIAL EXAMINATION OF WATER
BACTERIAL EXAMINATION OF WATER The bacteriological examination of water is performed routinely by water utilities and many governmental agencies to ensure a safe supply of water for drinking, bathing,
More informationwhether or not acid cleavage products were formed from the STUDIES ON CARBON METABOLISM OF ORGANISMS
STUDIES ON CARBON METABOLISM OF ORGANISMS OF THE GENUS MYCOBACTERIUM III. END PRODUCTS OF CARBOHYDRATE UTILIZATION AS DETERMINED IN SYNTHETIC MEDIA CULTURES MALCOLM H. MERRILL Department of Bacteriology
More information(1946), and Elek (1948) have described different methods. Stuart, van Stratum, and Rustigian (1945) found the method of Rustigian
A COMPARISON OF THE PHENYLPYRUVIC ACID REACTION AND THE UREASE TEST IN THE DIFFERENTIATION OF PROTEUS FROM OTHER ENTERIC ORGANISMS SVERRE DICK HENRIKSEN State Institute for Public Health, Bacteriological
More informationSUGAR IN BACTERIAL CULTURES' of the media, gas or acid production are the usual criteria taken
A RAPID METHOD FOR THE DETERMINATION OF SUGAR IN BACTERIAL CULTURES' H. R. STILES, W. H. PETERSON AND E. B. FRED From the Departments of Agricultural Chemistry and Agricultural Bacteriology, University
More informationOrganisms used. The routine test organism was a putrefactive anaerobe, Company, and Bacilus stearothermophilus, strain NCA 1518.
THE EFFECT OF OXIDATIVE RANCIDITY IN UNSATURATED FATTY ACIDS ON THE GERMINATION OF BACTERIAL SPORES NORMAN G. ROTH2 AND H. 0. HALVORSON Department of Bacteriology, University of Illinois, Urbana, Illinois
More informationRoutine Use of a Modified Eijkman
Routine Use of a Modified Eijkman Medium in the Examination of Oysters, Crabmeat, and Other Substances C. A. PERRY, Sc.D., F.A.P.H.A., AND A. A. HAJNA Bureau of Bacteriology, Maryland State Department
More informationSurvival of Aerobic and Anaerobic Bacteria in
APPLIED MICROBIOLOGY, Mar. 1968, p. 445-449 Copyright 1968 American Society for Microbiology Vol. 16, No. 3 Printed in U.S.A. Survival of Aerobic and Anaerobic Bacteria in Chicken Meat During Freeze-Dehydration,
More informationcontaining China blue-rosolic Acid (C.R.) indicator (Bronfenbrenner, organisms were obtained from one, in which they were
DISSOCIATION AND LACTASE ACTIVITY IN SLOW LACTOSE-FERMENTING BACTERIA OF INTESTINAL ORIGIN A. D. HERSHEY AND J. BRONFENBRENNER Department of Bacteriology and Immunology, Washington University School of
More informationTHE FERMENTATION OF PROPYLENE GLYCOL BY
THE FERMENTATION OF PROPYLENE GLYCOL BY MEMBERS OF THE ESCHERICHIA-AEROBACTER- INTERMEDIATE GROUPS K. PIERRE DOZOIS, GREGORY A. LEE, C. JELLEFF CARR, FRANK HACHTEL AND JOHN C. KRANTZ, JR. Departments of
More informationInfluence of Different Prebiotics and Probiotics on Selective Intestinal Pathogens
ISSN: 2319-7706 Volume 3 Number 10 (2014) pp. 657-663 http://www.ijcmas.com Original Research Article Influence of Different Prebiotics and Probiotics on Selective Intestinal Pathogens Anayata Sharma 1*
More informationA Modified Selenite Brilliant-Green Medium for the Isolation of Salmonella from Egg Products
19551 MODIFIED SELENITE BRILLIANT-GREEN MEDIUM 295 DAY, W. C., GOTTLIEB, S., AND PELCZAR, M. J. 1952 The biological degradatioin of lignin; The inability of Polyporous versicolor to metabolize sodium lignosulfonate.
More informationFitzgerald and Schmidt (1912) and Sears (1916, 1917) have demonstrated that bacteria can produce creatinine and the latter
PRECURSORS TO THE FORMATION OF CREATININE BY BACTERIA C. H. FISH AND T. D. BECKWITH Department of Bacteriology, University of California at Los Angeles Received for publication July 29, 1938 Creatinimne
More informationSTUDIES ON HEMOGLOBIN. III An Ultra-Micro-method for the Determination of Hemoglobin as a Peroxidase.
BY STUDIES ON HEMOGLOBIN. III An Ultra-Micro-method for the Determination of Hemoglobin as a Peroxidase. HSIEN WU (From the L' b)oratory of Physiological CCemistry. Peking Union Medical College, Peking)
More informationA Change in the Contagious Character of a Strain of Swine Influenza
SWINE INFLUENZA V. STUDIES ON CONTAGION BY RICHARD E. SHOPE, M.D. (From the Department of Animal and Plant Pathology of The Rockefeller Institute for Medical Research, Princeton, N. J.) (Received for publication,
More informationTHE EFFECTS OF ACIDITY UPON THE GROWTH OF PNEUMOCOCCUS IN CULTURE MEDIA CONTAINING PROTEINS
THE EFFECTS OF ACIDITY UPON THE GROWTH OF PNEUMOCOCCUS IN CULTURE MEDIA CONTAINING PROTEINS BY WILLIAM H. KELLEY, M.D. (From the Department of Medicine of the Duke University School of Medicine, Durham,
More informationBACTERIAL EXAMINATION OF WATER
BACTERIAL EXAMINATION OF WATER The bacteriological examination of water is performed routinely by water utilities and many governmental agencies to ensure a safe supply of water for drinking, bathing,
More informationorganisms. All cultures conformed with the usual cultural and serological characteristics of the species or groups designated.
THE FERMENTATION OF GLYCEROL BY STREPTOCOCCI I. C. GUNSALUS Ain J. M. SHERMAN Laboratory of Bacteriology, College of Agriculture, Cornell Univer8ity, Ithaca, New York Received for publication July 1, 1942
More informationby some of the laboratories from which they were obtained. been taken up in the order of their importance as nearly as
THE INFLUENCE OF VARIOUS CHEMICAL AND PHYS- ICAL AGENCIES UPON BACILLUS BOTULINUS AND ITS SPORES I. RESISTANCE TO SALT ZAE NORTHRUP WYANT AND RUTH NORMINGTON From the Bacteriological Laboratory of the
More informationbacteriology to an analysis of changes occurring in the sea. The FATE OF FRESH WATER BACTERIA IN T
FATE OF FRESH WATER BACTERIA IN T SEA VICTOR BURKE AD LENNA A. BAIRD Bacteriological Laboratories, State College of Washington, Pullman, Washington Received for publication October 30, 1930 Fresh water
More informationTHE BACTERIA RESPONSIBLE FOR APOCRINE ODOR*
THE BACTERIA RESPONSIBLE FOR APOCRINE ODOR* JOHN S. STRAUSS, M.D.f AND ALBERT M. KLIGMAN, M.D., PH.D. Shelley, et at. (), have shown that apocrine sweat is non-odorous when delivered to the surface but
More informationChanges in the Microflora of Bovine Colostrum During Natural Fermentation
27 f. Milk Food Techno/. Vol. 39. No. I, Pages 27-31!January, 1976) Copyright 1976, International Association of Milk, Food, and Environmental Sanitarians Changes in the Microflora of Bovine Colostrum
More informationThe Action of Chloroform -killed Suspensions of Enteropathogenic Escherichia coli on Ligated Rabbit -gut Segments
J. gm. nghobioi. (i966), 4, 898 Printed in Great Britain 9 The Action of Chloroform killed Suspensions of Enteropathogenic Escherichia coli on Ligated Rabbit gut Segments BY JOAN TAYLOR AND K. A. BETTELHEIM
More informationORGANIC MATTER' organic nutrients upon the growth of microorganisms, most of the experiments
BACTERIAL UTILIZATION OF LOW CONCENTRATIONS OF ORGANIC MATTER' CLAUDE E. ZOBELL AND CARROLL W. GRANT2 Scripps Institution of Oceanography, University of California, La Jolla Received for publication January
More informationNutritional information
3. Processing food 3.3 Food labels 3.3.2 Nutritional information ENERGY AND NUTRIENTS In addition to product information, labels include a host of nutritional information, in particular the product s energy
More informationEXPERIMENT 4 DETERMINATION OF REDUCING SUGARS, TOTAL REDUCING SUGARS, SUCROSE AND STARCH
Practical Manual Food Chemistry and Physiology EXPERIMENT 4 DETERMINATION OF REDUCING SUGARS, TOTAL REDUCING SUGARS, SUCROSE AND STARCH Structure 4.1 Introduction Objectives 4.2 Experiment 4a: Reducing
More informationEFFECTS ON THE THERMAL RESISTANCE OF BACTERIA. (1934). This author found that sucrose and glucose in concentrations
HEAT STERILISED REDUCING SUGARS AND THEIR EFFECTS ON THE THERMAL RESISTANCE OF BACTERIA J. G. BAUMGARTNER Research Laboratory, 36, Crimscott Street, London, S.E.1., England Received for publication March
More informationA new selective blood agar medium for Streptococcus pyogenes and other haemolytic streptococci
J. clin. Path. (1964), 17, 231 A new selective blood agar medium for Streptococcus pyogenes and other haemolytic streptococci E. J. L. LOWBURY, A. KIDSON, AND H. A. LILLY From the Medical Research Council
More informationNitrate and Nitrite Key Words: 1. Introduction 1.1. Nature, Mechanism of Action, and Biological Effects (Fig. 1)
7 Nitrate and Nitrite Key Words: Nitrate; nitrite; methemoglobin; blood pressure; asphyxia; spinach; spongy cadmium column; zinc metal; sodium nitrate; sodium nitrite; ammonia buffer solution; Jones reductor.
More informationCV. THE CHEMICAL NATURE OF VITAMIN C.
CV. THE CHEMICAL NATURE OF VITAMIN C. BY JOSEPH LOUIS SVIRBELY1 AND ALBERT SZENT-GYORGYI. From the Institute of Medical Chemistry, University of Szeged, Hungary. (Received April 25th, 1932.) HEXURONIc
More informationEXERCISE. Proteins,Amino Acids, and Enzymes VII: Oxidase Test. Suggested Reading in Textbook. Pronunciation Guide. Materials per Student
EXERCISE 30 Proteins,Amino Acids, SAFETY CONSIDERATIONS Be careful with the Bunsen burner flame. No mouth pipetting. The oxidase reagent is caustic. Avoid contact with eyes and skin. In case of contact,
More informationA MICRO TIME METHOD FOR DETERMINATION OF REDUCING SUGARS, AND ITS APPLICATION TO ANALYSIS OF BLOOD AND URINE.
A MICRO TIME METHOD FOR DETERMINATION OF REDUCING SUGARS, AND ITS APPLICATION TO ANALYSIS OF BLOOD AND URINE. BY JAMES A. HAWKINS. (From Ike Hospital of The Rockefeller Institute for Medical Research,
More information(Ostrolenk and Hunter, 1946) revealed that approximately 7 per cent of the spec- 197
COMPARATIVE STUDIES OF ENTEROCOCCI AND ESCHERICHIA COLI AS INDICES OF POLLUTION MORRIS OSTROLENK, NORMAN KRAMER, AND ROBERT C. CLEVERDON U. S. Food and Drug Administration, Washington, D. C. Received for
More informationIntrinsic and Extrinsic Parameters of Foods That Affect Microbial Growth
Lec.3 Food microbiology Dr.Jehan Abdul Sattar Intrinsic and Extrinsic Parameters of Foods That Affect Microbial Growth The ability of microorganisms to grow or multiply in a food is determined by the food
More information320 MBIO Microbial Diagnosis. Aljawharah F. Alabbad Noorah A. Alkubaisi 2017
320 MBIO Microbial Diagnosis Aljawharah F. Alabbad Noorah A. Alkubaisi 2017 Pathogens of the Urinary tract The urinary system is composed of organs that regulate the chemical composition and volume of
More informationTHE BACTERICIDAL PROPERTIES OF ULTRAVIOLET IRRADIATED LIPIDS OF THE SKIN
THE BACTERICIDAL PROPERTIES OF ULTRAVIOLET IRRADIATED LIPIDS OF THE SKIN BY FRANKLIN A. STEVENS, M.D. (From the Department of Medicine, College of Physicians and Surgeons, Columbia University, and the
More informationFood acidity FIRST LAB
Food acidity FIRST LAB objective To determine total acidity of milk, juice, vinegar and oil acid value Food acidity Food acids are usually organic acids, with citric, malic, lactic, tartaric, and acetic
More informationSUGARS AND GLYCOLYTIC ENZYMES OF SPINAL FLUID IN EPIDEMIC CEREBROSPINAL MENINGITIS
SUGARS AND GLYCOLYTIC ENZYMES OF SPINAL FLUID IN EPIDEMIC CEREBROSPINAL MENINGITIS By ROGER S. HUBBARD, NELSON G. RUSSELL, JR., AND NELLIE M. RUSSELL (From the Buffalo General Hospital, Buffalo, New York)
More informationERYSIPELOTHRIX RHUSIOPATHIAE1. ordinary culture media. This is especially true when pathogens are to be isolated SELECTIVE MEDIUM FOR STREPTOCOCCI AND
THE USE OF SODIUM AZIDE (NaNs) AND CRYSTAL VIOLET IN A SELECTIVE MEDIUM FOR STREPTOCOCCI AND ERYSIPELOTHRIX RHUSIOPATHIAE1 Department of Veterinary Hygiene, Division of Veterinary Medicine, Iowa State
More informationBY ZACHARY MODISPACHER 11 TH GRADE CENTRAL CATHOLIC HIGH SCHOOL
BY ZACHARY MODISPACHER 11 TH GRADE CENTRAL CATHOLIC HIGH SCHOOL INTRODUCTION Chicken is one of the most consumed meats in the world, though can pose health risks (salmonella). Salmonella was thought only
More informationMETABOLISM OF d-mannohepttjlose. EXCRETION OF THE SUGAR AFTER EATING AVOCADO
METABOLISM OF d-mannohepttjlose. EXCRETION OF THE SUGAR AFTER EATING AVOCADO BY N. R. BLATHERWICK, HARDY W. LARSON, AND SUSAN D. SAWYER (From the Biochemical Laboratory of the Metropolitan Life Insurance
More informationThe Effects of Alcohol and Nicotine on Microbial Flora. Jeff Van Kooten Grade 11 Pittsburgh Central Catholic High School
The Effects of Alcohol and Nicotine on Microbial Flora Jeff Van Kooten Grade 11 Pittsburgh Central Catholic High School Microbial Flora The internal and external flora has eukaryotic fungi, protists, and
More informationSTUDIES ON THE PROTEOLYTIC BACTERIA OF MILK
STUDIES ON THE PROTEOLYTIC BACTERIA OF MILK III. ACTION OF PROTEOLYTIC BACTERIA OF MILK ON CASEIN AND GELATIN WILLIAM C. FRAZIER AND PHILIP RUPP From the Research Laboratories, Bureau of Dairy Industry,
More informationGASTRIC FLORA OF FASTING HEALTHY SUBJECTS AND ITS RELATIONS TO ph
GASTRIC FLORA OF FASTING HEALTHY SUBJECTS AND ITS RELATIONS TO ph Pages with reference to book, From 113 To 116 Rakhshanda Baqai, Sarwar J. Zuberi, Pirzada M.A. Siddiqui ( PMRC Research Centre, Jinnah
More informationChapter 4. Anti-bacterial studies of PUFA extracts from Sardinella longiceps and Sardinella fimbriata. 4.1 Introduction
Anti-bacterial studies of PUFA extracts from Sardinella longiceps and Sardinella fimbriata C o n t e n t s 4.1 Introduction 4.2 Materials and Methods 4.2.1 Extract Preparation and Determination of PUFA
More informationVITAMINS, MINERALS AND THE GUT
VITAMINS, MINERALS AND THE GUT Nutrients Looking at individual nutrients that are involved with gut health can be misleading This is not about taking individual nutrients It supports more a whole food
More informationThe respiratory quotient is the relation by volume of the carbon dioxide DEXTROSE AND LE VULOSE IN HUMANS
415 THE METABOLIC EFFECT OF ENEMA TA OF ALCOHOL, DEXTROSE AND LE VULOSE IN HUMANS By THORNZ, M. CARPZNTBR NUTRITION LABORATORY OF THU CARNEGIS INSTITUTION OF WASHINGTON, BOSTON, MASS. Communicated April
More informationLaboratory report. Test: Leaky gut test. Sample material: stool. John Doe Main St 1 Anytown
1 / 5 Verisana LAB John Doe Main St 1 Anytown Surname, First name Doe, John DOB 02/13/1980 Sex male Laboratory # 20020181 Date collected 01/25/2018 Date received 02/01/2018 Report date 02/13/2018 Laboratory
More informationTSI AGAR INTENDED USE
TSI AGAR INTENDED USE TSI (Triple Sugar Iron) Agar is used for the identification of enterobacteria by the rapid detection of the fermentation of lactose, glucose (with or without gas production) and of
More informationSOME OBSERVATIONS ON THE STUDY OF THE INTESTINAL BACTERIA. (Received for publication, September 14, 1909.)
SOME OBSERVATIONS ON THE STUDY OF THE INTESTINAL BACTERIA. BY ARTHUR I. KENDALL. (From the Laboratory of Dr. C. A. Herter, New York.) (Received for publication, September 14, 1909.) The alimentary canal
More informationVitamin C and Ibuprofen Effects on Escherichia Coli. Timothy Leisenring Grade 11 Central Catholic High School
Vitamin C and Ibuprofen Effects on Escherichia Coli Timothy Leisenring Grade 11 Central Catholic High School Rationale for Experiment Commonly, ingested materials are investigated for effects on human
More informationFACTORS AFFECTING THE GROWTH OF MICRO-ORGANISMS IN FOODS
FACTORS AFFECTING THE GROWTH OF MICRO-ORGANISMS IN FOODS FACTORS AFFECTING THE GROWH OF MICRO-ORGANISMS IN FOODS Several factors related to the environment and the conditions in which food is stored influence
More informationExperimental. Schmidt, in his experiments, boiled his solutions
PROTECTION OF TRYPSIN FROM DESTRUCTION BY HEAT. BY D. IL DE SOUZA. (From the Institute of Physiology, University College, London.) E. W. SCHMIDT' has recently claimed: that trypsin in the presence of peptone,
More information(Mardeshev et al., 1948) and that the coenzyme of the decarboxylase has been
STUDIES ON THE ASPARTIC ACID DECARBOXYLASE OF RHIZOBIUM TRIFOLII DANIEL BILLEN AND HERMAN C. LICHSTEIN Department of Bacteriology, University of Tennessee, Knoxville, Tennessee Received for publication
More informationAnimal Digestion and Nutrition
Animal Digestion and Nutrition Competency: Analyze the parts and functions of the digestive system of farm animals By : ARI WIBOWO, S.Pt.,M.Si & SUHARDI, S.Pt.,MP Ruminants Objective: Describe the function
More informationAntimicrobial Effects of Vinegar. Daniel Crawford Grade 9 Central Catholic High School
Antimicrobial Effects of Vinegar Daniel Crawford Grade 9 Central Catholic High School Antibacterial Agents Humans interest in microbial growth/survivorship for over 100 years Many products/technologies
More informationMicrobiology Activity #6 Metabolism of Small Molecules.
Microbiology Activity #6 Metabolism of Small Molecules. Analysis of Carbohydrate Metabolism Organisms that use CO 2 as a carbon source and fix the carbon into biomass are autotrophs, usually obtaining
More informationSoil organic matter composition, decomposition, mineralization and immobilization
Soil organic matter composition, decomposition, mineralization and immobilization SOIL ORGANIC MATTER Substances containing carbon are organic matter. Soil organic matter consists of decomposing plant
More informationdetermined within a reasonably short period. The procedure
PHYSIOLOGICAL STUDIES ON RHIZOBIUM V. THE EXTENT OF OXIDATION OF CARBONACEOUS MATERIALS' 0. R. NEAL2 AND R. H. WALKER' Iowa State College, Ames, Iowa Received for publication March 28, 1936 The earlier
More informationNational Standard of the People s Republic of China. National food safety standard. Determination of pantothenic acid in foods for infants and
National Standard of the People s Republic of China GB 5413.17 2010 National food safety standard Determination of pantothenic acid in foods for infants and young children, milk and milk products Issued
More informationFOOD SPOILAGE AND FOOD PRESERVATION
FOOD SPOILAGE AND FOOD PRESERVATION Intrinsic Factors Affecting Microbial Growth ph Moisture Content Water activity Oxidation-reduction potential Physical structure of the food Available nutrients Presence
More informationfiltrates from serum when the deproteinization had been carried out with a solution of this acid 0.51 and 0.52 N.
FACTORS THAT INFLUENCE THE PASSAGE OF ASCORBIC ACID FROM SERUM TO CELLS IN HUMAN BLOOD By MARTIN HEINEMANN1 AND PAULINE M. HALD (From the Department of Internal Medicine, Yale University School of Medicine,
More informationChapter # 3. Microbial Growth GROWTH
Chapter # 3 Microbial Growth GROWTH It is defined as an increase in cellular constituents that may result in either Increase in cell number; or Increase in cell size However when it comes to microorganisms,
More informationpoints raised, and the following is an account of what I have done under touched, but my work has fallen under two main heads:
NOTES ON CREATININE. BY P. C. COLLS, late Assistant Demonstrator in Physiology, King's College, London. (From the Physiological Laboratory, King's College, London.) ABOUT two years ago, a lengthy correspondence
More informationHAGEDORN AND JENSEN TO THE DETER- REDUCING SUGARS. MINATION OF LARGER QUANTITIES OF XIV. AN APPLICATION OF THE METHOD OF
XIV. AN APPLICATION OF THE METHOD OF HAGEDORN AND JENSEN TO THE DETER- MINATION OF LARGER QUANTITIES OF REDUCING SUGARS. By CHARLES SAMUEL HANES (Junior Scholar of the Exhibition of 1851). From the Botany
More informationArtificial Sweetener Effects on Microbial Flora. Thomas Peilert Central Catholic High School
Artificial Sweetener Effects on Microbial Flora Thomas Peilert Central Catholic High School Problem Can the artificial sweetener Equal Original affect survivorship of Escherichia coli? Microbial Flora
More informationSTUDIES ON THE ENZYMES OF PNEUMOCOCCUS.
Published Online: 1 November, 1920 Supp Info: http://doi.org/10.1084/jem.32.5.583 Downloaded from jem.rupress.org on September 29, 2018 STUDIES ON THE ENZYMES OF PNEUMOCOCCUS. III. CARBOHYDRATE-SPLITTING
More information(*) (*) Ingestion, digestion, absorption, and elimination. Uptake of nutrients by body cells (intestine)
Human Digestive System Food is pushed along the digestive tract by peristalsis the rhythmic waves of contraction of smooth muscles in the wall of the canal Accessory glands. Main stages of food processing
More informationcerevisiae are affected by vitamins. similar claims were put forth in regard to their importance in the
VITAMIN EFFECTS IN THE PHYSIOLOGY OF MICRO- ORGANISMS C. H. WERKMAN From the Laboratories in Bacteriology, Iowa Agricultural Experiment Station, Ames Received for publication March 15, 1927 No sooner had
More informationinoculated to give an initial viable count of approximately 104 to 105 cells per ml, and incubated at 37 C with shaking, or under the desired gas
ENVIRONMENTAL CONDITIONS AFFECTING THE POPULATION DYNAMICS AND THE RETENTION OF VIRULENCE OF PASTEURELLA PESTIS: THE ROLE OF CARBON DIOXIDE E. A. DELWICHE,1 G. M. FUKUI, A. W. ANDREWS, AND M. J. SURGALLA
More information(1933) suggest this to be due to the greater affinity of the sucrose particle for
RELATIVE INHIBITION OF MICROORGANISMS BY GLUCOSE AND SUCROSE SIRUPS1 Massachusetts Agricultural Experiment Station, Amherst, Mass. Received for publication, December 29, 1941 In concentrations above 30
More informationFigure 1. Bacterial growth curve.
INTRODUCTION In order for suitable growth and division, a microorganism must be placed into a favorable environment. Bacterial growth refers to an increase in cell number rather than cell size. Bacteria
More informationReduction of Population Levels of Some Indigenous Bacteria by Lactobacilli in the Gastrointestinal Tract of Gnotobiotic Rats
Microbiol. Immunol. Vol. 21 (9), 495-503, 1977 Reduction of Population Levels of Some Indigenous Bacteria by Lactobacilli in the Gastrointestinal Tract of Gnotobiotic Rats Tsugio WATANABE, Masami MOROTOMI,
More informationINTESTINAL TRACT1 By J. DE LA HUERGA AND HANS POPPER. utilize this substance. TTMA or choline determination after oral administration
FACTORS INFLUENCING CHOLINE ABSORPTION IN THE INTESTINAL TRACT1 By J. DE LA HUERGA AND HANS POPPER (From the Hektoen Institute for Medical Research and the Departments of Pathology of Cook County Hospital
More informationRelation of the Heat Resistance of Salmonellae to
APPLED MICROBIOLOGY, Mar. 1970, p. 9- Copyright 1970 American Society for Microbiology Vol. 19, No. Printed in U.S.A. Relation of the Heat Resistance of Salmonellae to the Water Activity of the Environment1
More informationLACTOSE/ SUCROSE/D-GLUCOSE
www.megazyme.com LACTOSE/ SUCROSE/D-GLUCOSE ASSAY PROCEDURE FOR THE MEASUREMENT OF LACTOSE, SUCROSE AND D-GLUCOSE IN FLOURS K-LACSU 06/15 (100 Assays of each per Kit) Megazyme International Ireland 2015
More informationELECTROPHORETIC STUDIES OF SONIC EXTRACTS OF PROTEUS VULGARIS
ELECTROPHORETIC STUDIES OF SONIC EXTRACTS OF PROTEUS VULGARIS I. EFFECT OF GROWTH ENVIRONMENT ON ELECTROPHORETIC PATTERNS' SIDNEY D. RODENBERG Laboratory of Microbiology, Division of Biology, University
More informationAnimal Digestion and Nutrition. Objective 7.02: Understand the digestive process
Animal Digestion and Nutrition Objective 7.02: Understand the digestive process RUMINANTS Ruminant Animals Animals with complex digestive systems Capable of digesting material with a high fiber concentration
More informationMethods of food preservation
Methods of food preservation ACTIVITY 3 CLIL TECHNOLOGY SOME INTERESTING VIDEOS https://www.youtube.com/watch?v=zchoopshgz4 FOOD SPOILAGE https://www.youtube.com/watch?v=yrowhowiutk BACTERIA GROWTH https://www.youtube.com/watch?v=trxdlhg-2ho
More informationBlair Bean Grade 9 Pittsburgh Central Catholic Highschool
Blair Bean Grade 9 Pittsburgh Central Catholic Highschool Variety of organisms that live in and on the body Skin Gastrointestinal tracts Nose Pharynx Mouth Conjunctiva Provide moisture, nourishment, and
More informationEffect of dietary fiber on intestinal gas production and small bowel transit time in man13
ffect of dietary fiber on intestinal gas production and small bowel transit time in man13 John H. Bond,4 M.D. and Michael D. Levitt,5 M.D. ABSTRACT The influence of dietary fiber on intestinal gas production
More informationA STUDY OF THE CONCENTRATION AND PROPERTIES OF TWO AMYLASES OF BARLEY MALT
A STUDY OF THE CONCENTRATION AND PROPERTIES OF TWO AMYLASES OF BARLEY MALT BY M. L. CALDWELL AND S. E. DOEBBELING (From the Department of Chemistry, Columbia University, New York) (Received for publication,
More informationStreptococcus thermophilus which grows actively at temperatures
STREPTOCOCCI WHICH GROW AT HIGH TEMPERATURES Department of Dairy Industry, Cornell University, Ithaca, New York Received for publication, "April 16, 1931 INTRODUCTION Although streptococci have been exhaustively
More informationWhat is Dietary Fibre?
Fibre What is Dietary Fibre? Non digestible part of plant foods Consists of one or more of edible CHO polymers and synthetic CHO polymers Types of Dietary Fiber There are many different types of fiber,
More informationNONSPOREFORMING, ANAEROBIC BACTERIA'
THE FERMENTATION OF GLUCOSE BY CERTAIN GRAM-POSITIVE, NONSPOREFORMING, ANAEROBIC BACTERIA' New York State Agricultural Experiment Station, Geneva, N. Y. Received for publication June 30, 1945 The identity
More information