Anaerobe Systems PRAS Laked
                   Blood Agar (LBA) AS-115

View the full product insert:  LBA Insert.pdf

Formula

Pancreatic Digest of Casein, 10.0 g

Soy Peptone, 3.0 g

Animal Tissue, 10.0 g

Dextrose, 1.0 g

Yeast Extract, 2.0 g

Sodium Chloride, 5.0 g

Sodium Bisulfite, 0.1 g

Hemin (0.1% soln), 5.0 ml

L-Cysteine, 0.5 g

Vitamin K₁ (1% soln), 1.0 ml

Tryptophan, 0.2 g

Agar, 15.0 g

Laked Sheep Blood, 45.5 ml

Distilled Water, 1000.0 ml

 

Final pH 7.1 +/- 0.2 at 25 degrees C.

Final weight 16.0 g +/- 1.6.

                                                                                                               

Precautions

For IN VITRO DIAGNOSTIC USE only.  Approved biohazard precautions and aseptic techniques should be observed when using this product.  This product is for use only by properly-trained and qualified personnel.  Sterilize all biohazard waste prior to disposal.

Storage and Shelf Life

Storage:  Upon receipt, store at room temperature (13°C - 27°C) in original container until use.  Avoid overheating or freezing.  Do not use medium if there are signs of deterioration (shrinking, cracking or discoloration due to oxidation of media) or contamination.  The expiration date applies to the product in its original packaging and stored as directed.  Do not use product past the expiration date shown on the container.

Shelf Life:  90 days from date of manufacture.

 

Procedure

Specimen Collection:  Specimens for anaerobic culture should be protected from air (oxygen) during collection, transport and processing.  Consult appropriate references for detailed instructions concerning collection and transport of anaerobes.

Methods for Use:  LBA should be inoculated directly with clinical material or a broth that has been previously inoculated from clinical material.  Inoculated plates should be streaked to obtain isolated colonies, immediately placed in an anaerobic atmosphere and incubated at 35-37^oC for 18-48 hours.  Additional periods of incubation may be necessary to recover some anaerobes.  Detailed instructions for processing anaerobic cultures can be found in the appropriate references (1, 2, 3, 4, 5, 6).

 

Materials Required But Not Provided

Standard microbiological supplies and equipment such as loops, saline blanks, slides, staining supplies, microscope, incinerator / autoclave, incubators, anaerobic chamber, other culture media and serological and biochemical reagents.

 

Limitations

LBA will not provide complete information for identification of bacterial isolates.  Additional test procedures and media are required for complete identification. In some cases LBA may be overgrown with swarming Proteus spp. or Clostridium spp.  It is recommended that selective media such as Anaerobic Brucella Laked Blood Agar with Kanamycin and Vancomycin (LKV) and/or Anaerobic Brucella Blood Agar with Phenylethyl Alcohol (PEA) also be inoculated from clinical specimens to prevent such overgrowth and thus provide isolated colonies.  Consult reference materials for additional information (1, 2, 3, 4, 5, 6).

 

Quality Control

LBA should support good growth of members of obligate anaerobes found in clinical infections.  In addition, the medium should support typical pigment production by Prevotella melaninogenica and Porphyromonas asaccharolytica.

The following organisms are routinely used for quality control testing at Anaerobe Systems. 

Organism Tested	ATCC #	Results	Time (Hours)	Special Reaction
Bacteroides fragilis	25285	Growth	24 hrs
Prevotella melaninogenica	25845	Growth	24 – 48 hrs	pigmentt
Porphyromonas asaccharolytica	25260	Growth	24 – 48 hrs	pigmentt
Fusobacterium necrophorum	25286	Growth	24 hrs
Fusobacterium nucleatum	25586	Growth	24 – 48 hrs
Clostridium perfringens	13124	Growth	24 hrs
Peptostreptococcus anaerobius	27337	Growth	24 hrs
Staphylococcus aureus	25923	Growth	24 hrs

                               ^t  Pigment production may require more than 48 hours incubation

User Quality Control: The final determination to the extent and quantity of user laboratory quality control must be determined by the end user.

If sterility testing is to be performed on this product, the appropriate percentage of the original shipment amount should be incubated anaerobically and aerobically for 48 – 96 hours.

If the nutritive capacity of this medium is to be tested for performance, it is recommended that the following ATCC organisms be evaluated for growth.

 

Organism	Expected Growth	Special Reaction
B. fragilis	24 hrs	-
P. melaninogenica	24-48 hrs	Pigment
F. necrophorum	24 hrs	-
P. asaccharolytica	24-48 hrs	Pigment

                           ^t  Pigment production may require more than 48 hours incubation

 Physical Appearance:  LBA should appear opaque to translucent burgundy red in color.

 

References

1.        Dowell, V. R., Jr. and T. M. Hawkins.  1974.  Laboratory Methods in Anaerobic Bacteriology.  CDC Laboratory Manual.  USDHEW C. D. C. Atlanta, GA 30333.

 

2.        Dowell, V. R., Jr. and G. L. Lombard.  1977.  Presumptive Identification of Anaerobic Non-sporeforming Gram-negative Bacilli.  USDHEW, CDC.  Atlanta, GA 30333.

 

3.        Dowell, V. R., Jr., G. L. Lombard, F. S. Thompson and A. Y. Armfiedl.  1977.  Media for the Isolation, Characterization, and Identification of Obligately Anaerobic Bacteria.  USDHEW, CDC, Atlanta, GA 30333.

 

4.        Holdeman, L. V., F. P. Cato and W. E. C. Moore.  1977.  Anaerobe Laboratory Manual.  Virginia Polytechnic Institute and State University.  Blacksburg, VA 24061.

 

5.        Somer-Jousimies, H. R., Summanen, P., Citron, D. M., Baron, E. J., Wexler, H. M. and S. M. Finegold.  2002.  Wadsworth – KTL Anaerobic Bacteriology Manual.  Star Publishing Co., Belmont, CA 94002.

 

6.        NCCLS.  Quality Control for Commercially Prepared Microbiological Culture Media; Approved Standard- Third Edition.  (2004).  NCCLS document M22-A3.  NCCLS, 940 West Valley Road, Suite 1400, Wayne, PA 19087-1898.