Nutrient agar

Nfthr-. nutritive, nutrient, alimentary, -agar, m. nutrient agar, -aquivalent, n. nutritive equivalent or value, -biatt, n. (Bot.) storage leaf, -boden, m. nutrient medium, nutrient substrate, culture medium, -bouillon, -briUie,/. nutrient broth, nahren, v.t. feed nourish support. — nah-rend, p.a. nourishing, nutritive, nutritious, nutrient. 

A culture of NRRL 2773 is produced by growing the organism ing the following composition on a nutrient agar slant hav-... 

Methylprednisone 21-acetate (0.5 g), when hydrolyzed by means of aqueous alcoholic potassium bicarbonate yields 16 fnethylprednisone. An alternative method of the preparation of the compound of this example is as follows. Bacillus sphaericus var. fusifermis (A.T.C.C. 7055) is incubated on a nutrient agar (composed of Bacto-beef extract, 3 g Bacto-peptone,... 

Antibiotic activities are examined by transfer of seed culture of Bacillus subtilis on nutrient agar on a Petri dish. The seed culture for Bacillus subtilis is a simple basal media of... 

Bismuth sulphite agar. This medium was developed in the 1920s for the identification of Salmonella typhi in water, faeces, urine, foods and pharmaceutical products. It consists of a buffered nutrient agar containing bismuth sulphite, ferrous sulphate and brilliant green. 

The test solution is placed in a ditch cut in nutrient agar contained in a Petri dish, or it... 

In this technique the concentration of a drug in an agar plate may (theoretically) be varied infinitely between zero and a given maximum. To perform the test, nutrient agar is melted, the solution under test added, and the mixture poured into a sterile Petri dish and allowed to set in the form of a wedge (Fig. 11.6A). 

The first official test was published by the Food, Drug and Insecticide Administration of the US Department of Agriculture, in which portions of the preparation were placed on the surface of nutrient agar inoculated with Staph, aureus. After incubation the zones of inhibition, if ary, around the preparation were measmed. This test was modified later by incorporating 10% of horse serum in the agar to simulate conditions in a woimd and a control consisting of unmedicated base was also used in each experiment. This test is known as the cup-plate test (see also section 3.6.3 and Fig. 11.5). 

One usually tries to adjust experimental conditions so that only one plasmid or phage is introduced into a single cell. When that cell replicates on a plate of nutrient agar, it will produce millions of cells until a colony becomes visible to the naked eye. If cells are sufficiently diluted before they are spread onto the plate, each colony will consist of a clone derived from a single ancestral cell. If each cell originally contained only one copy of the phage or plasmid vector, each colony will contain recombinant DNA that is homogeneous. That is, each colony will contain cloned DNA. 

Blood of normal subjects was obtained from an antecubital vein, diluted 1 5 with pH 4.5 buffer,2 and autoclaved 30 minutes to convert bound cobalamin into its microbiologically active form serum was treated like blood. This procedure allowed estimation of total vitamin Bi2. For the subsequent inoculation of specimens (a) E. coli as a loopful from nutrient agar suspended in 25 ml of medium, (b) L. leichmannii, an 18-hour culture diluted 1 10 in basal medium, (c) E. gracilis, strain Z, and (d) O. malhamensis are inoculated directly from a 5-day culture grown in liquid maintenance medium. One drop into a culture flask served as inoculum. The bacteria required 18-hours for full growth protozoa, 4-5 days. 

Several types of testing were employed to evaluate the bactericidal efficacies of the coated substrates. Five of the coatings on circular glass cover-slips (12 mm diameter) were challenged with the bacterium Staphylococcus aureus (ATCC 6538). This was accomplished by adding a 50- jlL suspension of 10 CFU S. aureus to the surface of each sample. At predetermined contact times a 25- jlL aliquot was removed from the surface, quenched with sterile 0.02 N sodium thiosulfate, and plated on nutrient agar. The viable bacterial colonies were then counted after 48 h incubation at 37°C. Fabric samples were tested by two methods. In one, small squares (1.0-1.5 cm) were placed on a Tryptic Soy agar plate that was inoculated... 

Resistance Tests. Several transformants were tested for their ability to grow on all three selective media. These transformants were streaked onto nutrient agar plates containing 0.1% naphthalene, dibenzofuran, or... 

Figure 6. Ilyphae from N-limited nutrient agar grown cultures of C. versicolor showing (a) a thick walled skeletal hypha and (b) a thin walled generative hypha labelled for lignin-peroxidase. Label is seen throughout the hypha.1 walls with little labelling in the cytoplasm. Magnification x 15,700.

Figure 7. Higher magnification of generative hyphal walls from N-limited nutrient agar grown cultures labeled for lignin-peroxidase. Double layer of label on both margins of the hyphal wall. Magnification x 11,000.

Cotton swabs or RODAC plate (nutrient agar culture medium)... 

---