%PDF-1.5 %���� Divide the suspension into two tubes (0.5ml each), one labeled "TEST," the other labeled "CONTROL." Negative result: Appearance of unlysed colonies indicates a negative result. Then, inoculate heavy inoculum from the blood agar via a sterile inoculating loop. Scientific classification; Domain: Phylum: Class: Order: Family: Genus: Species: Binomial name; Streptococcus pneumoniae (Klein 1884) Chester 1901. The bile solubility test is based on the observation that pneumococcal cells lyse when sodium desoxycholate (bile salts) is applied to the colony under specified conditions of time and temperature. Your email address will not be published. 0 Principle of bile solubility test. At last, observe the tubes for the turbidity clearance. FA stain (digitally colored). The bile solubility test is based on the observation that S. pneumoniaecells visibly lyse when 2% or 10% sodium desoxycholate is applied, while other alpha-hemolytic streptococci do not. The reason for the dissolution of the Streptococcus pneumoniae is due to the presence of an autolytic enzyme (Autolysins), which activates in response to the bile spot reagent. Then equally, partition the solution containing saline and bacterial suspension into two separate test tubes, and label them as control and test culture. The bile (sodium deoxycholate) solubility test distinguishes S. pneumoniaefrom all other alpha- hemolytic streptococci. The bile solubility test is based on the observation that Streptococcus pneumoniae visibly lyse when 2% or 10% sodium desoxycholate (bile salts) is applied to the colony under specific condition of time and temperature, but other Streptococci do not lyse. Your email address will not be published. Then add a drop of bile spot reagent on a glass slide. Vigorously shake the test tubes to ensure uniform mixing of the cell suspension with the reagent. The mechanism of the bile solubility test depends upon the “Autolysis reaction”. Bile Solubility Test- Principle, Procedure, Result Interpretation, Examples and Limitation. The basis of bile solubility test is the lysis of pneumococcal cells when bile salts especially sodium desoxycholate and sodium taurocholate is applied to the colony under particular conditions of time and temperature, whereas other streptococci do not. 30 0 obj <> endobj To prepare 2% of bile solubility reagent: Take 2 grams of sodium deoxycholate bile salt in 100 ml of sterile water. The higher concentration of bile salt may also restrain the autolysis of Streptococcus pneumoniae. Positive result: Cocci will not appear on microscopic examination. It is prepared by dissolving bile salt like sodium deoxycholate in sterile water. Positive result: Clearing of turbidity represents a positive test result. *�k���3�_�-�j����M�MP�V������S�cN��>V"���Z2�D��;nԌc�vHg5g��n�s�N��~�. Published 9 March 2014 Last updated 13 August 2018 — see all updates. Bile solubility test. [���'�^FJ��no��� Bile Solubility test: Principle, Procedure, and Results Principle. Bile solubility test makes the use of 2% and 10% bile spot reagent of sodium deoxycholate solution. It results in the cell disruption of Streptococcus pneumoniae, after which an intracellular autolytic enzyme activates. Since the discovery of the germ theory of disease, scientists have been finding ways to harvest specific organisms. Bile solubility test: Related Topics These medical condition or symptom topics may be relevant to medical information for Bile solubility test. Streptococcus pneumoniae; S. pneumoniae in spinal fluid. ]2� d�b���l���е��*^уĿ��>�ٜU5��⁙��L�q�Dݩ$��~���+:�J�j�82$�WK��"�M���CNu=hj�ع�V��h�X�/�˻:dUj!��(�z.oՀ�Z�W$fi6h.�-h�q2 HCc�aH��z�!y�]Լ07���'ed�^���l�X�q�䁭J���H��Q��k����# ���E1����"��̵jz�5���/��0m��Tlq�ZqqS��0��� r�#�"_$�O��"��:��H�L�gs}Z/Iͱ�A�90|�y�Cw&�? Positive result: Appearance of the disintegrated colony after 30 minutes represents a positive test result. The turbidity of both the test tubes should be in between 0.5-1. 55 0 obj <>stream The autolysin amidase causes autolysis of bacterial cell by disintegrating the peptidoglycan backbone. Then, subject the test plates into an incubator at 35-37 degrees Celsius for a maximum of 30 minutes. It is an indirect method, which involves the following steps: Test Results Bile solubility test is a biochemical test that distinguishes bile soluble and bile resistant α-haemolytic streptococci. Add one drop of bacterial suspension over the clean, grease-free glass slide. Required fields are marked *. The sodium deoxycholate solution reagent carries out the sequential degradation of the bacterial cell, by first lowering the surface tension between the medium and the cell membrane interface. The bile solubility test includes the following limitations: Therefore, we can conclude that the bile solubility test helps in the identification and differentiation of Streptococcus pneumoniae from other streptococci, based on the property of bile solubility. endstream endobj 31 0 obj <>>>/Filter/Standard/Length 128/O(��t�d��������J����Ý׿N���)/P -1340/R 4/StmF/StdCF/StrF/StdCF/U([.��N�����ޫQ� )/V 4>> endobj 32 0 obj <> endobj 33 0 obj <> endobj 34 0 obj <>stream Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. Difference Between Precipitation and Agglutination Reaction, Difference Between Apoptosis and Necrosis, Difference Between Plasmolysis and Deplasmolysis, Difference Between Absorbent and Adsorbent. Diagnostic microbiology is the study of microbial identification. This test is used to differentiate Streptococcus pneumoniae, which is soluble in bile and bile salts, from alpha- hemolytic Streptococcus which are insoluble.. In a test culture tube, add two drops of bile salt reagent, whereas in control tube adds two drops of saline. Streptococcus pneumoniae is the only strain that emulsifies on reaction with bile solubility reagent, while the other α-haemolytic streptococci do not undergo such reaction. Examine the plates for the appearance of disintegrated colony. Sodium deoxycholate (2% in water) will lyse the pneumococcal cell wall. Bile salts, specifically sodium deoxycholate and sodium taurocholate, have the capacity to selectively lyse S. pneumoniae when added to actively growing bacteria in agar or broth media. SMI TP 5: bile solubility test Information on UK Standards for Microbiology Investigations for bile solubility tests. *$>�q���ER��p"|�&�A�@FӇ���e��;�s�.�ݿA�}: �8��g������]P��:�s}r)���}����5�e�w8�d~5(���Vc$~#�ao5'Aag�T�.��nr�ν�m)�ϟ�� endstream endobj startxref Negative result: Here, the suspension remains turbid. S.pneumoniae is bile sensitive, as it emulsifies by the reaction of bile salt reagent with its intracellular autolytic enzyme, whereas other strains are bile resistant. It involves direct and indirect method, where the bile salt reagent can be added directly on to the isolated test organism and indirectly added to the medium containing saline and heavy suspension of the test organism. Streptococcus pneumoniae is the only strain that emulsifies on reaction with bile solubility reagent, while the other α-haemolytic streptococci do not undergo such reaction. Negative result: Cocci appears on the microscopic examination.

Blue Jay Nesting Habits, Collective Noun For Beads, Multiplication Worksheets Grade 2, Algorithms In C, Adkar Model Example, Kraft Cheese Ingredients,