Laboratory Analysis
Justyna Sudyka
1. a. Clostridium sporogenes grew throughout all of the thioglycollate broth, but there was more growth towards the bottom. The aerobic TSA + glucose plate did not have any growth, but the anaerobic plate did have growth. Escherichia coli grew throughout all of the thioglycollate broth as well, but the organism was clustered slightly more towards the top. There was growth in both aerobic and anaerobic TSA + glucose plates. Micrococcus luteus only grew at the top of the thioglycollate broth and it grew in the aerobic TSA + glucose plate but not on the anaerobic plate. Pseudomonas aeruginosa grew towards the top of the thioglycollate broth, but slightly below the section in direct contact with the air. There …show more content…
The results of the two culture methods do agree with each other. The growth pattern for C. sporogenes indicates that it is an obligately fermentative bacterium. E. coli and E. faecalis both had growth patterns that indicated an organism that was a facultative anaerobe. The growth pattern for M. luteus represents that of an aerobic organism, and the growth pattern of P. aeruginosa matched up with that of a …show more content…
a. The Wescodyne was the most effective against E. coli and Staphylococcus aureus. The zone of inhibition around the Wescodyne for both bacteria was over 20 mm. Only Wescodyne was able to inhibit both bacteria. E. coli was inhibited by hydrogen peroxide and 70% ethyl alcohol. S. aureus was inhibited by Lysol and Scope.
b. The tests that were performed were not effective in distinguishing between bacteriostatic and bactericidal agents. The zone of inhibition may have been a result of both bacteriostatic and/or bactericidal properties. The disinfectants/antiseptics may have prohibited the bacteria from growing in the zone of inhibition, or cells that were able to grow initially could have been killed after they began to grow. Simply having a clearing does not provide enough information that can help to determine the correct mechanisms of the agents that were used.
c. The minute growth that was near the disc was most likely a resistant strain of that bacterial species. Resistant strains develop mechanisms that allow them to survive and reproduce despite the presence of certain antimicrobial agents (and antibiotics
Justyna Sudyka
1. a. Clostridium sporogenes grew throughout all of the thioglycollate broth, but there was more growth towards the bottom. The aerobic TSA + glucose plate did not have any growth, but the anaerobic plate did have growth. Escherichia coli grew throughout all of the thioglycollate broth as well, but the organism was clustered slightly more towards the top. There was growth in both aerobic and anaerobic TSA + glucose plates. Micrococcus luteus only grew at the top of the thioglycollate broth and it grew in the aerobic TSA + glucose plate but not on the anaerobic plate. Pseudomonas aeruginosa grew towards the top of the thioglycollate broth, but slightly below the section in direct contact with the air. There …show more content…
The results of the two culture methods do agree with each other. The growth pattern for C. sporogenes indicates that it is an obligately fermentative bacterium. E. coli and E. faecalis both had growth patterns that indicated an organism that was a facultative anaerobe. The growth pattern for M. luteus represents that of an aerobic organism, and the growth pattern of P. aeruginosa matched up with that of a …show more content…
a. The Wescodyne was the most effective against E. coli and Staphylococcus aureus. The zone of inhibition around the Wescodyne for both bacteria was over 20 mm. Only Wescodyne was able to inhibit both bacteria. E. coli was inhibited by hydrogen peroxide and 70% ethyl alcohol. S. aureus was inhibited by Lysol and Scope.
b. The tests that were performed were not effective in distinguishing between bacteriostatic and bactericidal agents. The zone of inhibition may have been a result of both bacteriostatic and/or bactericidal properties. The disinfectants/antiseptics may have prohibited the bacteria from growing in the zone of inhibition, or cells that were able to grow initially could have been killed after they began to grow. Simply having a clearing does not provide enough information that can help to determine the correct mechanisms of the agents that were used.
c. The minute growth that was near the disc was most likely a resistant strain of that bacterial species. Resistant strains develop mechanisms that allow them to survive and reproduce despite the presence of certain antimicrobial agents (and antibiotics