Abstract: 2-Deoxy-D-Ribose is used as a carbohydrate source which selectively differentiates all of the Salmonella spp., Arizona spp., and 60% of the Citrobacter freundii from other members of the Enterobacteriaceae family. By combining the 2-Deoxy-D-Ribose with Citrobacter freundii inhibitors and thioglycollic acid, sodium salt to impart semi-anaerobic conditions in the medium as well as suitable nutrients and buffers, a selective Salmonella broth is compounded which lends itself to automated identification or enumeration systems.

Abstract: The improved method of the present invention involves the removal of lipid inhibitors from Limulus amebocyte lysate to increase the sensitivity and quality of the lysate. The method comprises intimately contacting, as by mixing and stirring, Limulus amebocyte lysate with a selected binary liquid solvent system for a time sufficient to draw water into the solvent system from the lysate and to effectively extract and denature the lipid inhibitors in the lysate. The ability of the binary solvent to draw in water from the lysate and form, in effect, a new tertiary system is the important factor in this methodology. The amount of water drawn into the solvent is controlled by the amount of polar solvent in the solvent system. After this extraction and denaturation, the lysate is then separated from the solvent system and recovered in purified form of increased sensitivity.

Abstract: The sensitivity of Klebsiella and Enterobacter organisms to preselected antibiotics is determined with a medium consisting essentially of a nutrient source for Klebsiella and Enterobacter organisms, about 0.01 to about 0.03 g/l 2,4 dinitro phenyl hydrazone of .alpha.-Ketoglutaric acid, about 3.5 to about 6 g/l sodium desoxycholate and the preselected antibiotic.

Abstract: The presence of microorganisms in a sample is determined by culturing micrganisms in a growth medium which is in contact with a measuring electrode and a reference electrode and detecting the change in potential between the electrodes which arises by the migration and accumulation of said microorganisms adjacent the surface of the measuring electrodes thus forming a charge-charge interaction between said measuring electrode and accumulated microorganisms, by measuring the potential change with a high impedance potentiometer.

Abstract: A microorganism identification test container comprises a tray member provided with a plurality of integrally formed open wells. A number of the wells are microorganism identification test wells having biochemical test media which in hydrated form permits growth of microorganisms with the generation of a volatile color-forming compound. Another number of wells are negative control wells corresponding to each of the test wells provided and including an inhibitor which in aqueous solution prevents color formation in the negative control wells from the volatile color-forming compound generated in the test wells. The wells are preferably disposed in a number of generally parallel rows or lines wherein one line or row contains a series of biochemical test media and an adjacent line or row contains the corresponding negative control medium for each test.

Abstract: A broth medium for the detection of DNAse-positive microorganisms. The medium contains conventional nutrients for growing the microorganisms, a source of essential divalent cations to insure activity of the DNAse and a biological indicator comprising DNA, toluidine blue and lambda carrageenan in sufficient quantity so that the medium turns from blue to a visually distinguishable reddish-pink or reddish-violet color in the presence of DNAse-positive microorganisms.

Abstract: In accordance with the invention there is provided a method for identifying or testing an anaerobic microorganism wherein an aqueous suspension of a culture of the microorganism having a culture density of about 2.times.10.sup.8 cells/ml, is brought into contact with an aqueous solution containing an oxidation-reduction indicator which substantially irreversibly undergoes a change in color upon being reduced and a biodegradable test substrate compound which, when catabolized by a microorganism, will engender reduction of the indicator, said aqueous suspension containing nutrient in a concentration sufficient to support microorganism culture growth without engendering reduction of the indicator when said suspension contacts said solution, and said suspension also containing a compound which reduces O.sub.2 but does not reduce the indicator.

Abstract: The detection of "significant bacteriuria" in a urine sample is accomplished by measuring the head space gas oxygen consumption in a closed vial system. A sample to be tested is introduced into a sealed vial containing a growth medium and the head space gas oxygen concentration initially measured. After a suitable incubation period, the oxygen concentration above the sample is again measured using a closed sample loop. A decrease in the head space oxygen concentration below a predetermined level indicates the presence of a significant quantity of oxygen consuming microorganisms in the sample.

Abstract: Improved hypertonic culture media, employing mannitol, erythritol or sorbitol in place of sucrose to provide high osmolarity, are described for the detection and growth of microorganisms in body fluids, particularly of bacteria in blood specimens.

Abstract: Method and automated apparatus are disclosed for determining the time of detection of metabolically produced hydrogen by coliform bacteria cultured in an electroanalytical cell from the time the cell is inoculated with the bacteria. The detection time data provides bacteria concentration values. The apparatus is sequenced and controlled by a digital computer to discharge a spent sample, clean and sterilize the culture cell, provide a bacteria nutrient into the cell, control the temperature of the nutrient, inoculate the nutrient with a bacteria sample, measures the electrical potential difference produced by the cell and measures the time of detection from inoculation.

Abstract: An improved IMViC test method is disclosed which is suitable for conducting multiple bacterial IMViC tests on solid media. The method comprises (1) obtaining a suitable culture of bacteria by growing the bacteria first in LST broth, then in EC broth and finally on EMB agar; (2) inoculating a test plate containing solid test media for the IMViC tests in separate compartments; (3) incubating said inoculated test plate; and (4) determining the results of the tests. The period of incubation for the IMViC tests has been reduced to 48 hours by this method. A test plate suitable for use with this method is also disclosed.

Abstract: A broth medium for the detection of Group D enterococci in urine. The medium employs neomycin sulfate to inhibit growth of Staphylococcus aureus, potassium tellurite to inhibit growth of gram-negative organisms, and ferric ammonium citrate and esculin hydrolysate indicators.