Inoculation Of Solid Media

Specimens can be inoculated (plated) onto solid media either quantitatively by a dilution procedure or by means of a quantitative loop, or semiquantitatively using an ordinary inoculating loop. Urine cultures and tissues from burn victims are plated quantitatively; everything else is usually plated semiquantitatively. Plates inoculated for quantitation are usually streaked with a 1:100 or 1:1000 loop, as shown in Figure 5-4, A. The original streak line is cross-struck with an ordinary inoculating loop to produce isolated, countable colonies. Plates inoculated for semiquantitation are usually struck out in four quadrants, as shown in Figure 5-4, B. The inoculum is applied by swabbing a dime-sized area or placing a drop of liquid specimen on the plate. The original inoculum is then cross-struck with an ordinary reuseable nichrome inoculating loop (quadrant one) or a sterile plastic single-use loop. The

Alpha Hemolysis

Figure 5-2 Examples of various types of hemolysis on blood agar. A, Streptococcus pneumoniae showing alpha (a)-hemolysis (i.e., greening around colony). B, Staphylococcus aureus showing beta ((J)-hemolysis (i.e., clearing around colony). C, Enterococcus faecalis showing gamma (y)-hemolysis (i.e., no hemolysis around colony).

Figure 5-2 Examples of various types of hemolysis on blood agar. A, Streptococcus pneumoniae showing alpha (a)-hemolysis (i.e., greening around colony). B, Staphylococcus aureus showing beta ((J)-hemolysis (i.e., clearing around colony). C, Enterococcus faecalis showing gamma (y)-hemolysis (i.e., no hemolysis around colony).

Figure 5-3 MacConkey agar. A, Escherichia coli, a lactose fermenter. B, Pseudomonas aeruginosa, a non-lactose fermenter.

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Bacterial Vaginosis Facts

Bacterial Vaginosis Facts

This fact sheet is designed to provide you with information on Bacterial Vaginosis. Bacterial vaginosis is an abnormal vaginal condition that is characterized by vaginal discharge and results from an overgrowth of atypical bacteria in the vagina.

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