A microbiological assay has been developed for chromomycin A(3), an antitumor antibiotic showing promise in human trials. The assay bacterium is a derived strain of Streptococcus faecalis resistant to methotrexate. Studies with mice revealed that relatively high concentrations of this antibiotic were maintained in the blood, kidneys, and liver of mice after a single-dose intraperitoneal injecti...

It was reported previously that coenzyme A contained pantothenic acid bound in such a manner as to make it unavailable in microbiological tests (1). A liberation of p;alanine on acid hydrolysis indicated early the presence of pantothenic acid, which was confirmed by chick assay (2). While the chick assay for pantothenic acid and the p-alanine assay by the yeast growth test yielded equivalent am...

We have developed a Real-Time PCR assay to detect M. tuberculosis using the iCycler iQ detection system by TaqMan assay directly on the clinical specimen. A total of 513 clinical samples were taken from patients with suspected tuberculosis and other patients that had an active mycobacterial infection, as well as patients with diagnosed tuberculosis who were receiving antitubercular therapy. The...

Antibiotic concentrations in human sera were estimated in 5 to 6 hr by a modified microbiological assay. By using Staphylococcus aureus and Streptococcus pyogenes as the assay organisms, the seeded assay plates were preincubated for 2 to 6 hr and then were stored at 4 C until used for assay. Paper discs saturated with the specimen were placed on the preincubated assay plates with reference disc...

A logarithmic-ratio microbiological assay has been developed for the estimation of concentrations of actinobolin (or inhibitory equivalents) in human saliva. The utility of this assay has been demonstrated by presenting data that show concentrations of this antibiotic (or inhibitory equivalents) detected in saliva or saline after incubation at 37 C for periods as long as 6 hr. The results of so...

A high-pressure liquid chromatography (HPLC) method has been developed for the analysis of cefazolin in serum. Serum was deproteinized by the addition of 6% trichloroacetic acid and injected onto a reverse-phase column with a mobile phase of 10 to 15% methanol in 1% aqueous acetic acid. Cefazolin chromatographed without interference from ultraviolet-absorbing components of serum, with a retenti...

A simplified microbiological assay for vitamin B12 estimation, completed on microtitre plates using a colistin sulphate resistant strain of Lactobacillus leichmannii (NCIB 12519), and cryopreserved cultures is described. The new assay correlated well with a more conventional "tube" assay and was not influenced by the presence of antibiotics in serum. Evaluation of assay performance showed excel...

The meat industry has taken several measures to expand its shelf life, such as frozen storage and thermal treatments. Hence, the valuable content in red meat, vitamin B12, could be affected by this handling. This study aimed assess B12 losses Algerian Hamra lamb caused (06 months at -18 °C) boiling for 45 minutes 80 °C with regard modifications water-holding capacity (WHC). Samples of Longissim...

Based on the requirement of a glutathione-deficient mutant strain of Saccharomyces cerevisiae to take up external glutathione for growth on synthetic media, a simple agar diffusion test for quantitative detection of total glutathione from various sources was established. Glutathione concentrations can be reliably detected in a less expensive way, requiring less technical effort compared to enzy...

Doctor, V. M. (University of Texas, Houston). Microbiological assay for thymine using a mutant of Streptococcus faecalis. J. Bacteriol. 84:17-22. 1962.-A rapid microbiological assay procedure for the determination of thymine was devised. The test organism, Streptococcus faecalis Akt, a mutant of S. faecalis ATCC 8043, gives one-half the maximal growth response to 1.6 mug of thymine (assay range...