scholarly journals The urinary excretion of orally administered pteroyl-l-glutamic acid by the rat

1971 ◽  
Vol 123 (5) ◽  
pp. 907-914 ◽  
Author(s):  
J. A. Blair ◽  
E. Dransfield
Keyword(s):  
Oral Dose ◽  
Oral Administration ◽  
Urinary Excretion ◽  
Glutamic Acid ◽  
Decomposition Products ◽  
Naturally Occurring ◽  
Pteroylglutamic Acid

1. The urinary excretion of folates after oral administration of [2-14C]pteroyl-l-glutamic acid was studied by assaying the radioactivity in the urine and in materials purified and characterized by t.l.c. 2. Radioactivity excreted was 6.8, 5.9 and 30.7% of the oral dose in the first 24h after doses of 3.1, 32 and 320μg/kg respectively. 3. Extensive decomposition of urinary folates to pteroyl-l-glutamic acid was prevented by antioxidants or collection of urine frozen. 4. At the three dosages, two major and one minor radioactive compounds were isolated. One of the major metabolites was 5-methyltetrahydropteroylglutamic acid. The others were unidentified but were not pteroylglutamic acid, 7,8-dihydro-, 5,6,7,8-tetrahydro-, 5- or 10-formyl-tetrahydro-, 5,10-methylidyne-tetrahydro-, 5-formimidoyl-tetrahydro-, 5,10-methylene-tetrahydro-, 5-methyltetrahydro-pteroylglutamic acid, nor any decomposition products of these compounds formed during isolation. Labelled unconjugated pteridines were absent. 5. Labelled pteroyl-l-glutamic acid was displaced by oral administration of unlabelled pteroyl-l-glutamic acid (1.6mg/kg) when given 3.5h after, but not when given 24h after the labelled dose. 6. The results show that orally administered [2-14C]pteroyl-l-glutamic acid is absorbed without metabolism and is then metabolized into naturally occurring tetrahydro-folates. 7. These findings are discussed with reference to previous work.

scholarly journals Time Pattern of Vitamin B12Co60 Urinary Excretion in Man After Oral Administration and Parenteral "Flushing"

Blood ◽  
1956 ◽  
Vol 11 (4) ◽  
pp. 352-356 ◽  
Author(s):  
WILLIAM R. BEST ◽  
WENDELL A. LANDMANN ◽  
LOUIS R. LIMARZI
Keyword(s):  
Oral Dose ◽  
Oral Administration ◽  
Urinary Excretion ◽  
Pernicious Anemia ◽  
Intrinsic Factor ◽  
Time Pattern ◽  
Number Of Patients ◽  
Excretion Rates ◽  
The Individual ◽  
Factor Concentrate

Abstract Serial urine collections in a number of patients with pernicious anemia given 2 µg B12Co60 orally followed in two hours by 1000 µg nonradioactive vitamin B12 showed little urinary radioactivity at any time. When these tests were repeated together with a potent oral dose of intrinsic factor concentrate, there was little activity during the first four hours. Peak excretion rates occurred most commonly between 6 and 12 hours after ingestion of radioactive B12, sometimes even later. The time of peak excretion was fairly characteristic for the individual. Secondary peaks occasionally occurred, and only slight radioactivity usually remained after 24 hours. It is postulated that the delayed peak is related to the time it takes for B12 to be transported in the intestine to the point of absorption or to the duration of the intracellular metabolic processes of absorption. For most purposes the use of fractional urinary collections is not necessary.

The Application and Functional Progress of γ-Poly-Glutamic Acid in Food: A Mini-Review

2020 ◽  
Vol 26 (41) ◽  
pp. 5347-5352
Author(s):  
Guoliang Wang ◽  
Qing Liu ◽  
Ying Wang ◽  
Jingyuan Li ◽  
Yue Chen ◽  
...  
Keyword(s):  
Glutamic Acid ◽  
Food Industry ◽  
Water Solubility ◽  
Drug Carrier ◽  
Physical Property ◽  
Coating Material ◽  
Vaccine Adjuvant ◽  
Food Ingredient ◽  
Naturally Occurring

γ-Poly-glutamic acid (γ-PGA) is a naturally occurring homo-polyamide produced by various strains of Bacillus. As a biopolymer substance, γ-PGA possesses a few predominant features containing good water solubility, biocompatibility, degradability and non-toxicity. Based on this, γ-PGA can be used in pharmaceutical, such as drug carrier/deliverer, vaccine adjuvant, and coating material for microencapsulation, etc. Moreover, it has also been applied in a broad range of industrial fields including food, medicine, bioremediation, cosmetics, and agriculture. Especially, γ-PGA is an extremely promising food ingredient. In this mini-review, our aim is to review the function and application progress of γ-PGA in the food industry: e.g., improving taste and flavor, enhancing physical property, and promoting health.

scholarly journals Cochleate formulations of amphotericin b designed for oral administration using a naturally occurring phospholipid

2021 ◽  
pp. 120688
Author(s):  
Antonio Lipa-Castro ◽  
Valérie Nicolas ◽  
Angelina Angelova ◽  
Ghozlene Mekhloufi ◽  
Bastien Prost ◽  
...  
Keyword(s):  
Oral Administration ◽  
Amphotericin B ◽  
Naturally Occurring

Pharmacokinetics of the Antimalarial Drug, AQ-13, in Rats and Cynomolgus Macaques

2004 ◽  
Vol 23 (3) ◽  
pp. 179-189 ◽  
Author(s):  
Sandhya Ramanathan-Girish ◽  
Paul Catz ◽  
Moire R. Creek ◽  
Benjamin Wu ◽  
David Thomas ◽  
...  
Keyword(s):  
Oral Dose ◽  
Oral Administration ◽  
Antimalarial Drug ◽  
Dose Range ◽  
Plasmodium Species ◽  
Repeat Dose ◽  
Nonlinear Kinetics ◽  
Dose Administration ◽  
Blood Concentrations ◽  
Cynomolgus Macaques

The purpose of this study was to evaluate the bioavailability and pharmacokinetics of a new antimalarial drug, AQ-13, a structural analog of chloroquine (CQ) that is active against CQ-resistant Plasmodium species, in rats and cynomolgus macaques. Sprague-Dawley rats ( n = 4 /sex) were administered a single dose of AQ-13 intravenously (i.v.) (10 mg/kg) or orally (20 or 102 mg/kg). Blood and plasma samples were collected at several timepoints. AQ-13 achieved Cmax after oral administration at approximately 3 to 4 h and could be detected in blood for 2 to 5 days after oral administration. The ratio of area under the curve (AUC) values at the high and low dose for AQ-13 deviated from an expected ratio of 5.0, indicating nonlinear kinetics. A metabolite peak was noted in the chromatograms that was identified as monodesethyl AQ-13. Oral bioavailability of AQ-13 was good, approximately 70%. The pharmacokinetics of AQ-13 was also determined in cynomolgus macaques after single (i.v., 10 mg/kg; oral, 20 or 100 mg/kg) and multiple doses (oral loading dose of 50, 100, or 200 mg/kg on first day followed by oral maintenance dose of 25, 50, or 100 mg/kg, respectively, for 6 days). The AUC and Cmax values following single oral dose administration were not dose proportional; the Cmax value for AQ-13 was 15-fold higher following an oral dose of 100 mg/kg compared to 20 mg/kg. MonodesethylAQ-13 was a significant metabolite formed by cynomolgus macaques and the corresponding Cmax values for this metabolite increased only 3.8-fold over the dose range, suggesting that the formation of monodesethyl AQ-13 is saturable in this species. The bioavailability of AQ-13 in cynomolgus macaques following oral administration was 23.8% for the 20-mg/kg group and 47.6% for the 100-mg/kg group. Following repeat dose administration, high concentrations of monodesethyl AQ-13 were observed in the blood by day 4, exceeding the AQ-13 blood concentrations through day 22. Saturation of metabolic pathways and reduced metabolite elimination after higher doses are suggested to play a key role in AQ-13 pharmacokinetics in macaques. In summary, the pharmacokinetic profile and metabolism ofAQ-13 are very similar to that reported in the literature for chloroquine, suggesting that this new agent is a promising candidate for further development for the treatment of chloroquine-resistant malaria.

IDIOPATHIC HYPERGLYCINEMIA: A NEW DISORDER OF AMINO ACID METABOLISM

PEDIATRICS ◽  
1961 ◽  
Vol 27 (4) ◽  
pp. 539-550 ◽  
Author(s):  
William L. Nyhan ◽  
Margaret Borden ◽  
Barton Childs
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Oral Administration ◽  
Dietary Intake ◽  
Urinary Excretion ◽  
Cation Exchange ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Acute Illness ◽  
Progressive Decrease

The amino acids of blood and urine have been investigated using chromatography on cation exchange columns in the study of a patient with idiopathic hyperglycinemia. Marked increases in concentrations of glycine, serine, alanine, isoleucine and valine were found in the plasma. These changes were not reflected in increased excretion of these amino acids in the urine (with the exception of glycine). Restriction of the dietary intake of protein resulted in a decrease in the concentrations of glycine and other amino acids in the blood and urine, and there was a concomitant decrease in the frequency and severity of episodes of acute illness. The oral administration of leucine was found to induce a decrease in the levels of a number of amino acids in the patient and in controls. Continued decrease during the 3 hours of observation was noted for serine, isoleucine and valine. A mild but progressive decrease in threonine concentration was observed in the controls, while in the patient the concentration increased after the administration of leucine. Decreased levels at 1½ hours, returning toward the fasting levels at 3 hours, were observed for alanine, taurine and glycine. These apparently normal responses to leucine loads were not mediated through increase in the urinary excretion of the amino acids involved, and the data are interpreted to indicate entry of these amino acids into cells.

Human Metabolism and Urinary Excretion Kinetics of Nonylphenol in Three Volunteers after a Single Oral Dose

2021 ◽  
Author(s):  
Benedikt Ringbeck ◽  
Vladimir N. Belov ◽  
Christoph Schmidtkunz ◽  
Katja Küpper ◽  
Wolfgang Gries ◽  
...  
Keyword(s):  
Oral Dose ◽  
Urinary Excretion ◽  
Single Oral Dose ◽  
Human Metabolism ◽  
Excretion Kinetics ◽  
Kinetics Of
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